ATRESIA MICROTIA & YOUR CHILD

Chapter 4: Treatment

When Should We Begin Treatment?

Determine your child’s hearing loss as early as possible and begin treatment as soon as you can if conditions exist that can be corrected. The longer you wait, the more significantly hearing loss will affect your child’s development. In in our conferences around the world, we recommend parents attend even if your child is a few weeks old. You begin to learn, and we begin to fill in the HEAR MAPS score and assemble a treatment plan. As your child is old enough to undergo tests, we’ll be ready to plan treatment. Usually, a CT scan at 2.5 years of age is the last test needed before finalizing treatment.

Assemble a Team of Medical Professionals

The first question to ask yourself is “Who do I need on my team to care for my child?” I suggest the following list:

A list of medical professionals to include in your child’s
“Care Team,” as well as a brief description of their role.

Pediatrician

Your local pediatrician is a critical member of your child’s team. She or he will act as your urgent, go-to person for most medical needs during childhood. He or she may also be able to evaluate your child for the presence of a syndrome. Your pediatrician will carry out the important well-care aspects that are important to ear health, such as immunizations and physical development tracking.

Hearing Test Specialist (Audiologist)

While a hearing testing specialist is called an audiologist in most countries, physicians perform similar functions in some countries. As outlined in the Testing & Evaluation section, different technologies are needed to give critical information about your child’s hearing over time. A hearing test specialist will know what technologies are needed.

If a pediatric audiologist is available to you, get one on your team.

The pediatric audiologist’s experience with hearing loss evaluation and treatment in childhood is extremely beneficial for our care of your child. In some cases, hearing devices will be needed, and pediatric audiologists tune and care for the devices that are used. As with your pediatrician, it is best to find a pediatric audiologist close to your home if possible, as regular visits are needed.

Otologist

An otologist (which is what I do) focuses his or her practice on the care of ear disease. A few even focus on the care of ear disease in childhood. The otologist is responsible for helping you interpret diagnostic tests after ordering them, evaluating your child’s ear anatomy, interpreting CT scans, and performing surgery if needed. This person does not need to be local to you.

Plastic Surgeon

A plastic surgeon is responsible for the surgical correction of CAAM’s outer ear deformity. Choose a plastic surgeon who specializes in the reconstruction technique, that I describe later, you prefer. Your plastic surgeon does not need to be located close to home.

Craniofacial Surgeon

In about 10% of all patients, a craniofacial surgeon is needed to coordinate and deliver care for the jaw and sometimes the facial abnormalities associated with CAAM or related syndromes. Craniofacial surgeons are specially trained in surgery of the mandible (or jaw), midface, and orthodontic or dental care. This person can live a long way from you if one is not available in your immediate area. Frequently, your craniofacial surgeon can work with local orthodontists if required.

First Steps

After parents assemble their team of medical professionals, the natural question to ask next is: “What do I need to do next?” I suggest the following First Steps action items:

A list of medical professionals to include in your child’s “Care Team,” as well as a brief description of their role.

As soon as possible after birth, a hearing test should be done to determine if the inner ear and hearing nerve in the CAAM ear is intact and functioning normally.

Remember, don’t make the easy and tempting mistake of focusing only on the ear with CAAM.

In our experience, 23% of children with single-sided CAAM have hearing loss in their “good” ear.

If hearing loss is present on the side not affected by CAAM, serious implications on speech and language development are still possible. Fortunately, this hearing loss can usually be treated easily and quickly.

Through your pediatrician, a search for any of the syndromes known to cause CAAM is important. Many of these are identifiable at birth, but some may emerge later, and continuing follow up is important. If you are fortunate to be near a major medical center, a pediatrician may be available who specializes in identifying and treating genetic syndromes. Your pediatrician will know if such a local person exists. These specialists are called developmental pediatricians.

Beginning around one year of life, consultation with a speech pathologist may be a good idea. For example, if this is your first child, you are not used to what would be considered normal for a child’s age. A speech pathologist can compare your child’s speech and language development to that of other children their age. They may also be enlisted in your treatment team to perform speech therapy to help develop your child’s vocabulary, speech, and sentence structure. In some settings, specialized schools adept at educating and developing speech in children with hearing loss are available and can be a phenomenal addition to your child’s early life. Over time, our goal is to get hearing-impaired children enrolled and functioning normally in the school system. A speech pathologist will know what resources are available in your local area.

Within your child’s first year of life, identify and develop a relationship with an otologist. This medical doctor will interpret and apply diagnostic information generated by pediatric audiologists and speech therapists and help you formulate a treatment plan. Also, if any skin tags or excess tissue or abnormalities need to be removed early after birth, he/she will perform this minor procedure for your child without disrupting any tissue options to be used later in the reconstruction process. Your otologist also can interpret CT scans and perform surgery.

By the time your child is about two-and-a-half years old, you should select an outer ear reconstruction option and add a plastic surgeon to the team. It helps a lot (and improves results) if the team members communicate well, are used to working together, and coordinate well as treatment is completed.

A Brief Historical Perspective of CAAM Treatment

A brief review of the history of the craft of treating CAAM may be useful as you begin to learn about surgical options.

Traditionally, microtia repair was performed using a rib graft technique and included three or four separate surgeries beginning between 5 and 7 years of age, after the ribs could grow to sufficient size to use in creating an outer ear. Using these techniques described decades ago, sections of three separate ribs were removed from the front of the chest wall and used to form a scaffold that mimicked the outer ear. The rib scaffold was then inserted under the skin to reconstruct the microtia defect. This process required several separate surgeries to complete and lasted over several years. After the rib graft microtia repair was completed, usually by about 10–12 years of age, ear canal surgery would then be performed.

As you read above, it is well known that stimulation of a sense during a critical period of development is crucial to the development of that sense—for example, the critical period of speech development described in Chapter 1. In the 1990s, I was the first surgeon to perform ear canal surgery before microtia repair. This change was pioneered to provide hearing to the developing brain and language centers of children with CAAM early in their life and developmental trajectory, at a time when maximal stimulation may occur. The new order of surgery challenged traditional medical practice at the time. In the early days, before I made this change, the average age of atresia repair was over 11.2 years of age—at which point the majority of the brain development associated with language has already passed.

We now perform hearing restoration surgery routinely at three years of age. The results on hearing and development are amazingly different.

My first publication of this work occurred in 2009 in several peer-reviewed medical journals. This change was directly facilitated by the development of the MEDPOR technique for microtia repair and reduced the total number of surgeries needed from four to two.

Our patients were happy with this reduction in the number of surgeries, travel, time away from home, psychological impact, and so on. I am so pleased young children can have restorative procedures without going through an operation more than four to six times. We have also seen improved language and speech and developmental progress in our youngest patients when hearing is achieved early in their life.

Several patients then asked if the Atresia and Microtia surgeries could be performed at one time. That polite and thoughtful question lead to an entirely new way to treat CAAM. Today, we can complete the ear canal and outer ear procedures in one single surgery in some patients. Together, Dr. John Reinisch and I performed the first combined CAAM surgery in the world in January 2008. Today, I have completed hundreds of CAAM surgeries together with several surgeons. It is now commonplace for patients to select this combined option for CAAM repair.

Over the past 20 years, I have intentionally targeted the largest problems, complications, and limited outcomes for treatment of children and adults with CAAM. By doing so, we enjoy great progress in areas where results have been improved. I still have my original list from the beginning of the 21st century. The list is certainly shorter now, but we hope to make further improvements as we go along.

Surgical Options for Canal Surgery

As you have learned previously, patients with a CT scan score of 6–10 are typically best treated with the surgical creation of an ear canal. The flow diagram below will help guide treatment decisions. A temporal bone CT scan should be done at a minimum of 2.5 years of age, and not earlier, unless directed by a medical professional. While the inner ear and the middle ear bones are fully grown at birth, the bone around them grows rapidly over the first years of life and is not adequately developed to determine surgical candidacy until the child is 2.5 years old or greater. It is through this bone that an ear canal must be made. We must wait for the bone to form adequately before giving a score for the CT scan. We cannot use a CT scan at one year, for example, to determine the chance of success for surgery to make an ear canal because the bone through which the canal must pass is not yet sufficiently developed.

Note that grades 1–4 are best treated with implantable hearing devices, which are described further below. Scores of 5 can occasionally have canals created—such as in bilateral CAAM—but full hearing restoration may be less likely (but still helpful in certain patients).

A road map to treatment plan options based on CT scan score.

Complex surgical equipment and facilities are needed to give a high chance of success. Surgical repair of CAAM is one of the most technically demanding surgeries that exists. The OR facilities require an excellent surgical microscope, special instrumentation, micro-drills, facial nerve monitors, laser, porous polyethylene microtia prostheses, in some cases customized middle ear bone replacement prostheses, and, in other cases, liposuction equipment. I cannot stress too much how important the correct equipment and staff is to the success of canal surgery. Since this is a challenging surgery, the ultimate results are achieved in operating rooms and by operating room teams who specialize in this surgery day after day, in the same facility with the same equipment.

Additionally, anesthesia for children undergoing surgery is a specialty in itself. I myself handpick anesthesiologists to staff our Surgery Center, and they are critical to the safety and success of the surgery. While most parents may not think of the large number of professionals needed to expertly perform these procedures, excellent team members are a critical component of success. As with any human endeavor, the world’s best results are achieved when the same procedure is done time after time with the same focused team of experts working with the finest equipment in the same environment.

We operate under the guidelines that “if we would choose this equipment and this team to operate on our child, then we will do the same for your child.”

The surgical equipment required to perform atresia repair surgery at the highest level includes:

 

• Facial Nerve Monitor: Electrodes are inserted into the muscles of the face after the patient is under anesthesia. Specially designed monitors are connected. Any stimulation of the facial nerve during surgery will result in a muscle twitch in the face. The muscle twitch is sensed and turned into an alarm sound to alert the surgeon and medical team, thus adding safety and protecting the facial nerve from injury.

Facial nerve monitors in place, which are used to protect against injury to the nerve during surgery.

• Operating Microscope and Specialized Instrumentation, including lasers, sub-millimeter dermatome, and micro-drills

The operating microscope and numerous instruments required to perform successful CAAM surgery.

Canal Surgery Situations

As you will learn about below, ear canal surgery can occur in five situations:

1. When a normal outer ear is present with no ear canal or a partial ear canal
2. After rib graft microtia repair is complete
3. As a first step six months or more before separate microtia repair
4. At the same time as microtia repair with a Combined Atresia Microtia repair
5. Following PPE microtia repair. This combination is highly discouraged, as it puts the microtia repair at risk and should be done only in unusual situations.

 

The following are images of some of our patients who have had canal surgery:

Scenario 1: Normal outer ear with surgically created ear canal.

Scenario 2: Outer ear reconstruction by rib graft method completed prior to surgical creation of the canal in the correct position.
 

Scenario 3: Canal surgery is performed first, followed by secondary PPE microtia repair surgery a minimum of 6 months later.

Scenario 4: Combined Atresia Microtia (CAM) repair, which entails creation of a canal and reconstruction of the outer ear with PPE in a single surgery.

Patients with adequate scores on CT scan are candidates for the creation of an ear canal. Surgery can be performed as a separate procedure (to be followed six months or more later by MEDPOR (PPE) microtia reconstruction) or in a single combined surgery with PPE microtia reconstruction performed in one day. Patients are discharged the same day as surgery in both cases.

Canalplasty

The surgery is performed under general anesthesia and requires approximately two hours for completion. Discharge takes place one to two hours after surgery. The ear canal is created in the normal position symmetric with the opposite ear in the case of unilateral CAAM. As you see in the images below, the new canal comes out just behind the small ear of microtia.

This image shows the location where the ear canal should have
developed. In CAAM, this is instead solid bone, which is removed using specialized drills to create a canal.

During surgery, the abnormal bone present where the ear canal should have formed is removed using micro-drills and suction irrigation. Small diamond-tipped burrs of different sizes between 6 mm and 0.5 mm that rotate and sand away bone are used to sculpt the ear canal in the proper shape and direction. Continuous irrigation with saline solution removes the small bone chips and keeps the remaining tissues cool and healthy.

Artist’s illustration of a drill being used to sculpt the ear canal.

Progressively smaller burrs are used to remove the bone of the canal, stopping short of the middle ear bones, which are attached to the inner surface of the bone wall that is sculpted away to form the ear canal.

A laser is used to remove the last portions of the bony connection to the middle ear bones, freeing them to transmit sound vibrations for the first time.

Artist’s illustration of the laser being used to sculpt the native middle ear bones and free them to conduct sound vibrations.

After laser sculpting of the middle ear bones, they are checked to make sure they are mobile and formed adequately. If not, middle ear bone reconstruction using a custom prosthesis may be needed to bring hearing up to desired levels.

Since no eardrum is present, one must be created. A three-layered eardrum is fashioned, which mimics the same layers as a normal eardrum. The middle layer is a type of tissue called fascia, which is transplanted from the surface of the muscle above the ear and shaped to fit against the middle ear bones like a normal eardrum. Medial to the fascia, the body forms an inner layer of mucosal tissue during the healing process. Finally, the outermost layer is formed by part of the skin graft taken to line the newly constructed ear canal.

An ear drum is created using fascia and secured to the middle ear bone chain in the appropriate position.

The ear canal is then lined with a split thickness skin graft that covers both the lateral surface of the newly transplanted eardrum and the surface of the newly created ear canal. Skin from the scalp has proven to be the most like normal skin, and the donor site heals without any scar. We have pioneered this donor site for skin in CAAM. A thin section of skin is removed, leaving the hair follicles intact in the scalp. The hair grows back on the scalp normally, and no hair grows on the skin transplanted to the ear canal.[vii]

A split thickness skin graft (STSG) is harvested from the scalp, leaving the hair follicles intact, which will grow back through the graft site. The skin is used to line the newly created canal.

Packing is placed inside the ear canal that holds the eardrum and skin graft in position for two to three weeks as the body grows blood vessels into the transplanted tissue. The packing is removed at intervals in the postoperative period while the newly constructed hearing mechanism progressively heals. Between visits, we ask patients to place antibiotic drops on the packing at specified intervals, prevent water from entering the reconstructed ear canal, and to avoid high impact or jarring activity.

 

A graphic depicting the packing placed in the ear canal at the time of surgery, and a rough estimate of when it is removed in the postoperative period.

Combined Atresia Microtia Repair

Combined Atresia Microtia (CAM) Repair for CAAM is a single-step surgery where both defects of the ear canal and the outer ear are corrected in a single surgery.[viii] An ear canal is created and the outer ear is reconstructed with an implant made of porous polyethylene (PPE), described below. Children should be three years of age and ~15 kg or more in weight. Two factors decide the earliest age we perform CAM surgery. The first is safety. General anesthesia is safest in children three years of age or older. As the procedure takes six to eight hours, anesthetic considerations for young children are paramount. We specifically use pediatric anesthesiologists familiar with the metabolism of the necessary medicines by children. Also, the amount of inhaled anesthetics is minimized by injecting local numbing agents (lidocaine and bupivacaine) both before the procedure begins and after it ends. As a result, patients feel no pain when they wake up.

This photo was taken in the operating room immediately after completion of a right ear CAM repair. A protective silicone outer ear mold and head bandage are placed prior to the child waking up.

All CAMs performed at our institution have been accomplished as an outpatient procedure with same-day discharge. Because of our careful anesthesia processes, children can return home within a few short hours after surgery is complete.

 

The same patient two weeks later. The outer ear mold and dressing have been removed, but the ear canal packing is still in place. The sponge in the ear canal will be removed at week three.

Coincidentally, 3 years of age is also a good age for surgery because a significant amount of growth of the head and ear toward adult size has already occurred. Figure 1 is illustrative of this growth pattern. As can be seen, the outer ear has reached 88% of adult size by 3 years of age and 92% of adult size by 7 years of age.[ix]

A graphical representation of head growth (percent of adult average size, y-axis) vs. age in years. By 3 years–the earliest age canal or CAM surgery can be performed – the structures of the head have reached 88% of average adult size. By age 7, they are 92% of adult average.

Both rib and PPE surgical techniques require implant size estimation based on anticipated final pinna size after growth has occurred by approximately 18 years of age. As such, the reconstructed ear and ear canal will appear slightly larger than the normal side in patients with unilateral CAAM. Later in life, when the structures have fully matured, both ears will match in appearance.

 

 

This boy is six months post-op after right CAM surgery and has hearing in the normal range (approximately ~90% of what a normal non-CAAM ear hears).

A frequent question is which technique of outer ear reconstruction gives the best hearing results. Hearing results following microtia repair using rib graft, PPE in CAM technique, and PPE in separate canal and microtia repair are identical. While hearing outcomes are the same, there are other risks and benefits that differ between these reconstructive approaches, which will be discussed in more detail later in the book. However, hearing outcomes are comparable between all reconstructive surgical approaches.

A comparison of hearing outcomes and reconstruction techniques. Note that there is no significant difference in hearing outcome between these techniques.

Microtia repair results utilizing PPE—whether implanted at the same time as canal surgery in CAM repair, as a second-stage procedure following initial canal surgery, or as a stand-alone surgery without ear canal creation—are nearly identical, with the following exception:

• Due to the ear being less mobile when a canal is in place, the PPE implant was more prone to fracture in the event of a strong blow to the ear in our early series. Still, overall fracture rates were low. Early results showed a fracture in just over 5% of patients. After instituting more significant welding of the connection points of the PPE scaffold, we believe we have this complication virtually eliminated, regardless of surgery approach.

Microtia repair results utilizing CAM repair differ from separate atresia repair and microtia repair surgery as follows:

• CAM patients are less likely to see the PPE scaffold become inferiorly or anteriorly displaced over time compared to patients who have atresia repair and microtia repair at different times. We believe this is due to the more vigorous suspension of the PPE with a tissue flap we can preserve to suspend the PPE implant in CAM surgery—a significantly stronger tissue than other suspension techniques applied in microtia repair following atresia repair. This tissue flap is not able to be used to suspend the PPE implant in a separate surgery approach, leading to slightly higher rates of implant displacement over time.
• CAM patients are less likely to experience canal stenosis than patients with separate surgeries.

 

In the operating room, an outer ear mold is made of soft material that hardens and is held in place with sutures. The blue outer ear mold stays in place for two weeks, and it cannot be taken off by children. Parents do not have to care for the mold in any way but must only keep their child from activities which might cause impact to or jostle the healing repair. The blue mold is removed in CAM patients ~2 weeks following surgery.

An example of the custom blue outer ear mold, which is sewn into place immediately after completion of a CAM procedure. This mold will stay in place for 2 weeks to protect the reconstructed ear before removal in clinic.

The opportunity for a “one and done” surgical procedure with CAM repair is extremely attractive to parents (and most patients!), especially to those traveling a long distance for services. A cooperative effort between pediatric plastic surgery, otology, and anesthesia is necessary to achieve excellent results in this complicated and long surgical procedure. To date, surgical results and complication rates in CAM are similar to or better than other forms of atresia and microtia repair. This makes CAM repair a good option for properly selected patients.

Ear Canal Mold

At the final post-op visit (approximately three weeks after canal surgery, or four weeks after CAM surgery), a custom ear canal mold is made that exactly fits the anatomy of each patient. This mold is made of material that reduces scar formation and promotes healing. The mold is used nightly during sleep for four months after surgery, with one drop of antibiotic placed in the ear canal before the mold is inserted.

A custom blue mold is made for the patient’s ear canal at the final postop appointment. Typically, this mold is worn for 4 months after creation, to prevent stenosis of the canal. If secondary outer ear surgery is performed after initial canal surgery, a new canal mold must also be made ~3 weeks after the outer ear reconstruction, to be worn for another 4 month period.

By using this mold in combination with exacting surgical techniques, we have been able to reduce the incidence of stenosis after canal surgery and CAM to under 2% of patients (compared to stenosis rates of approximately 20-30% worldwide). Use of the mold is critical to the long-term success of the repair and reduces the most common complication worldwide (stenosis) to a low level.

Complications of Surgery

Long and short-term complications occur in less than 10% of patients. These complications are typically treatable and require re-operation in less than 3% of patients.

Infection of the PPE implant is possible in the immediate postoperative period, but this has occurred in only two patients early on in our surgical series. A change to stronger intravenous antibiotic given at the start of surgery has eliminated PPE infections in the last 175+ patients. No case of ear canal infection has occurred.

In a normal hearing system, the eardrum is in direct contact with the middle ear bone chain, allowing direct transmission of incoming sound vibrations to the inner ear and brain. However, eardrum movement away from the ossicles (called lateralization) may occur late or early after surgery. Usually, pressure from the middle ear—such as otitis media—has been responsible. In the last several years, altered surgical techniques to secure the fascia graft used for tympanic membrane reconstruction has dropped this problem to just under 3% of patients. If hearing loss accompanies eardrum lateralization, revision surgery may be indicated.

Stenosis has been the largest and most common complication of atresia repair and may occur in up to 30% of patients worldwide. By implementing minimally traumatic surgical approaches, skin graft coverage of the bony canal, as well as other unique surgical techniques, we have been successful in markedly reducing this complication. Since 2012, the addition of a custom-made ear canal mold made three to four weeks post-op and worn for four months during sleep only (and discontinued thereafter) has reduced canal stenosis in our patients to under 2%.

Sensorineural hearing loss (e.g., damage to the hearing nerve) may occur with any ear surgery but has not been experienced in our CAM series. Similarly, facial nerve injury with resultant paresis or paralysis can occur from atresia repair. Worldwide, the risk of injury to the facial nerve is 1-2%. To date, my atresia patients have no cases of permanent facial nerve injury.

In dissecting the tissue flap used to cover the PPE outer ear implant, injury is possible to a small branch of the facial nerve that controls the muscles used to frown and raise the eyebrow on that side of the face. This is rare but can occur. Special care is taken in the operating room to monitor movement of the face and avoid permanent injury to the nerve.

Skin graft loss in the ear canal and or inadequate healing of the eardrum may also occur. Mucosal tissue may then instead grow and resurface on the ear canal, which may create a moist ear canal. Inadequate healing or lack of hygiene of the ear canal after healing can allow damaged skin to heal poorly in 2% of patients. Re-surfacing of the ear canal with a new skin graft and/or ear canal repair is needed in only a small percentage of patients. Most can be managed with topically applied preparations and treatment alone and do not require revision.

In this figure, worldwide complication rates based on published papers are compared to the complication rates in our patient series at Global Hearing (GHI).

A comparison of complication rates worldwide versus in our patients at Global Hearing (GHI).

Late complications may, of course, occur as well. These may require revision surgery at some point in a child’s life. Revision rate curves with predictive analytics estimate approximately 10% of children will need revision surgery at some point in their lives. This may be due to a cause that would injure a normal eardrum (for example, a middle ear infection or wave striking the head during surfing) or a cause specific to canal repair surgery (such as lateralization of the eardrum or displacement of the PPE implant downward over the canal opening) among other rarer causes.

Cleaning the New Canal

Our skin constantly makes new cells and sheds old cells. On the outside of the body, these cells simply fall off or are washed away with baths and showers. In the ear, the cells can build up. Normal ear canal skin grows from the inside on the surface of the eardrum toward the outside of the ear canal. The normal ear canal is self-cleaning in most of us. When skin is transplanted from a different site as we use it in canalplasty or CAM, it does not migrate the way normal skin migrates. As a result, skin can build up in a reconstructed ear, forming a flaky coating on the canal and eardrum. This build-up can block hearing and give germs a way to take hold and cause an infection.

During the first year following surgery, the ear will need to be cleaned by a local ear, nose, and throat doctor with a microscope (also called an otolaryngologist) two to four times. After the ear is fully healed, the cleaning intervals space out and finalize at one or two times per year for the remainder of a patient’s life.

How to Prepare Your Child for Surgery

When it comes to recovering from surgery, children are much more resilient than most people think. Most of the time, it is harder on parents than on children!

I have found it to be important to communicate with children about approaching surgery. While detailed information isn’t required, answering the questions of what they will feel and see before, during, and after surgery satisfies a child’s naturally curious nature.

Here are some useful communication tips I’ve learned over the years:

General Communication Tips Before and After Surgery

• Give information to children at age-appropriate levels. For example, a three-year-old is satisfied with a brief description such as, “We are going to California, and Dr. Roberson will make your small ear look and hear like your other ear.” Avoid too much technical detail. Older children may need more detailed explanations. You know your child and can judge how much to share, as well as how to share it.
• Answer any questions with brief and age-appropriate facts. This open attitude is a good way to reduce a child’s concern in most situations.
• Avoid being secretive. Holding back can cause anxiety and distrust when your child inevitably figures out you have not been fully honest.
• Your child will not feel much, if any, pain just after surgery. This is due to the use of an injection of a numbing solution similar to what a dentist uses. This medication is injected before a child awakes from surgery. Later in the evening of surgery, the ear will hurt mildly and can be controlled with pain medication by mouth. There are no shots on the day of surgery. Nothing hurts as your child goes into the operating room.
• About half of children use pain medication the first night after surgery and then no more. The remainder of patients benefit from pain relief the day following surgery. Less than 5% of patients use any pain medication after that.
• Your child can read your level of anxiety or worry. Being confident and relaxed goes a long way with children as surgery approaches. Talk to your spouse or other adults about your anxiety and fear and remain strong and gently confident in front of your child.

 

Share Details about the Day of Surgery

• Your child will go to sleep by breathing from a mask similar to that of an astronaut or jet pilot.
• When your child wakes up, there will be a wrap around the ear and head. This needs to remain in place for a short time to keep them safe.

Advice for after the Day of Surgery

• Recovery occurs quickly over the first several days after surgery. Usually, parents are amazed at how fast children recover and begin acting normally. Most of the time you spend in California can be a wonderful family time.
• Mix your trip to California with a reward. Examples might include a trip to nearby locations, such as Yosemite, San Francisco, or Disneyland. The excitement of the upcoming adventure will focus your child (and you!) beyond the surgery. Traveling by car is easy, and our patients enjoy the many wonderful places they can visit in this state. It is also a time of togetherness for you with your child that may prove to be a wonderful time and memory.
• Keep a photo and/or print diary of your child’s recovery. You can look back on it later and appreciate your journey. The reminder is also good for children as they recover and grow up; they will know how much you sacrificed to give them the gift of hearing. I have seen this appreciation grow throughout patients’ lives, especially when they have their own children. The experience of being a parent themselves gives them a newfound understanding of how much you did for them at a tender time.

The effort you put into finding the best solution for this challenge is an act of love—and one that you deserve credit for going through.

Hearing Devices

Patients who are not candidates to have an ear canal created surgically or those who have had an ear canal created but need more hearing are treated with an alternative method of supplying sound to the hearing nerve. Our goal is to provide hearing to every ear. Once sound enters the inner ear of the affected ear, the electrical signal passes along the hearing nerve and enters the brain, just as it does in a normal ear.

Fortunately, a variety of devices are available to achieve this goal. In this section, I describe the important advantages and disadvantages of devices that Global Hearing uses, as well as how each works. Selecting the correct device is a complex decision and should involve your otologist. Frequently, more than one option is possible. This section is designed to augment, not replace, your discussions with your team of medical professionals about your child’s best option or options.

New devices are always rapidly developing, and better devices will likely become available during your child’s hopefully long and wonderful life. Different devices are available at different locations around the world. Technology that is now the best will not always be the best in the future, so try not to make decisions that make other wonderful options impossible later. It is important to choose technology from a stable company that is likely to exist during the entirety of your child’s life.

Adopt a philosophy of “burn no bridges” when a hearing device is needed and selected. In other words, avoid any device which destroys the possibility of using other devices in the   future.

How Hearing Devices Work

Hearing devices work in one of three ways:

• Bone Conduction
• Air Conduction
• Direct Stimulation

Bone Conduction Devices

Bone conduction devices involve external processors with a microphone and implanted portions connected to the bone of the skull. They turn sound into a vibration and transmit that vibration to the bone of the skull through the implanted portion. Bone vibration that happens anywhere on the skull travels to the cochlear and hearing nerves of both ears, where it produces an electrical signal.

Sound transmission to the skull bone occurs by one of three methods:

1. Direct contact of the vibrating device to a surgically implanted abutment.
2. By coupling the external device to a surgically implanted magnet with the skin intact in between.
3. By pressing the external device against the skull’s skin with an elastic headband without an implanted portion.

Air Conduction Devices

Air conduction devices are the standard hearing aids worn by many with hearing loss. These devices need to be programmed in a slightly different way for children with CAAM, but they are the same type of devices worn by many older individuals with nerve (or sensorineural) hearing loss you learned about earlier in this book.

Air conduction hearing devices receive environmental sound, process it electronically, and augment it in a customized way for each patient. A tiny speaker in the ear canal then releases the processed sound into the ear canal at a volume louder than when it was received. Each sound is customized for each patient, similar to how a stereo equalizer makes sounds softer and louder, depending on what the listener finds pleasing and functional.

An ear canal must be present to use air conduction devices. When middle ear bone abnormalities prevent sound from improving to a normal level after canal surgery, air conduction hearing devices can bring sound up to a normal level.

Direct Stimulation Devices

Direct stimulation devices are surgically implanted hearing devices that apply a direct vibrating connection to the structures of the middle or inner ear, resulting in transmission of sound specifically to the ear in which they are surgically implanted. In current devices, an external speaker picks up sound and processes it electronically. The signal is transmitted across the skin to the inner implanted device which receives, decodes, and applies an electrical signal to a vibrating attachment to the middle ear bones or inner ear. These devices stimulate only the implanted ear.

Bone Conduction Hearing Devices

Cochlear BAHA Connect

Made by Cochlear Corporation from Australia, BAHA stands for Bone Anchored Hearing Aid. This product was the first brought to market and introduced in 1999 by ENTific of Sweden, which was then purchased by Cochlear Australia in 2005. It has been used for about three decades.

The device includes a surgically implanted titanium screw, which is surgically placed into the skull bone above and behind the ear. Attached to the implanted titanium device is an abutment, which comes through the skin and is hidden by the hair. It is a few millimeters in diameter and extends beyond the skin a few millimeters. The external processor clicks into the abutment and can be easily placed and removed for sleep or in the presence of water, which causes damage. With the external processor attached and fully operational, the device extends from the skin surface behind the ear approximately 20 millimeters.

Oticon Ponto

A nearly identical device first made by Oticon in 2006, the Ponto is an alternative to the BAHA Connect. It includes a similar implanted component to which the external processor is attached. Both the BAHA and the Ponto transmit sound vibrations to the skull bone, which travel to both inner ears as described above. These two devices compete regarding sound quality and additional features.

These images show examples of the BAHA Connect or Oticon Ponto, which includes a surgically implanted titanium screw that interacts with the external processor.

Soft Band (BAHA or Ponto)

With soft band devices, sound is transmitted to the inner ear by placing the identical processor used in the device’s implantable version on an elastic headband instead. The headband holds the processor to the head. The device can stimulate hearing without a surgical procedure and can be fitted the same day a patient is seen.

Young patients and patients who don’t want a surgical procedure frequently use this device. Others use it when waiting to institute other treatment types. Patients with bilateral CAAM should be fitted with this device within the first few months after birth. (See special conditions below.)

Cochlear BAHA Attract

This newer device (2013) couples vibration between the implanted portion and an external processor by the attraction of two magnets. Nothing comes through the skin. The device is held in place on the scalp by magnetic attraction. The external processor is the same as that of the BAHA Connect but projects out further from the scalp due to the magnet.

An image of the BAHA Attract, which includes a surgically implanted magnet that allows the external processor to be held on by magnetic attraction.

MedEl BoneBridge

MedEl Corporation of Austria first introduced a bone conduction hearing device in 2013 that implants the vibration-producing component under the skin. (The devices above leave the vibration-producing portion outside the body.) Nothing comes through the skin.

A magnet holds an external processor in place, which includes the microphone, battery, and software. The external device transmits sound across the skin to the internal device. The vibrating portion of the device is 9 mm thick and can be difficult to place in young children, as their skull thickness is less than 5 mm at five years of age. While some surgeons move the device down to the thicker bone of the lower skull, called the mastoid, this placement can interfere with placement of the microtia repair implant (either rib or PPE). As such, this device may be best reserved for adults. The device is not FDA approved and therefore not available in the USA.

Air Conduction Hearing Devices

Multiple manufacturers produce air conduction hearing devices. The worldwide market is close to 7 billion U.S. dollars. They fit the ear canal with custom molds and do not require surgery. Varieties exist for placement in the canal, in the ear, or behind the ear. They are used when awake and must be removed in a wet environment. Batteries are required every few days to power them.

Examples of air conduction hearing aids, which can amplify incoming sound in the presence of an ear canal and boost
hearing levels.

Many choices of hearing aids exist, and the device best suited for each patient is determined by an audiologist specializing in hearing aid fittings. For children, pediatric audiologists are the best choice for seeking advice.

In some varieties, the device is held in place by the outer ear. With rib graft implants, the groove behind the ear typically is not present, and these devices must be held on with double-sided tape. In patients with PPE implants, the device must not push on the skin overlying the implant, as it may lead to skin injury and PPE implant problems. Both precautions are handled easily with a few tips from your audiologist.

Direct Stimulation Devices

MedEl Vibrant SoundBridge

MedEl offers another device for hearing restoration in a small number of patients. The implanted portion is situated under the skin above and behind the ear. An external processor picks up sound and passes it to the internal device. The two are held together by magnetic attraction. No part of the device comes through the skin.

The internal implant behind the ear is connected by a thin wire to an additional vibrating component about twice the size of a grain of rice. This component, called the floating mass transducer, can be surgically placed in the middle ear and attached to a middle ear bone, or to a part of the ear where sound is transmitted.[x] The vibrations generated by the transducer are directly transmitted through the hearing system and on to the brain.

Images of the MedEl Vibrant SoundBridge implantable device.

As an interesting side note, the inventor of the Vibrant SoundBridge device has hearing loss and himself received implantation with this device. The images you see in the bottom right are actual photos of his device when it was surgically placed. He and I worked together when I was in training at Stanford University, in the hearing research facility where he first invented this device. Years later, I did the surgery for him, which was when these pictures were taken.

Disadvantages of Bone Conduction Hearing Aids (BCHAs)

Stimulation with a bone conduction hearing aid (BAHA, Ponto, Sophono, BoneBridge) stimulates both inner ears with the same signal. Since the brain needs two separate data streams to localize sounds, a bone conduction hearing aid does not provide the information needed for the brain to perform this function. Bone conduction hearing aids do not allow patients to localize sound even if two are worn.

Likewise, since the brain needs two ear data streams to hear normally in background noise, and since BCHAs do not provide it, hearing in noise with BCHAs is not ideal. BCHAs are most helpful in low to moderate noise situations. We have seen repeatedly that children with unilateral CAAM who wear a BCHA voluntarily remove these devices in moderate to high noise situations. The reason is the good ear—the non-CAAM ear—is getting sound from both the normal ear canal and hearing mechanism AND from the BCHA. When sound environments get louder, the two sounds together are confusing, and patients hear with only the normal hearing ear.

The sound quality of implanted bone conduction devices is also somewhat synthetic. Patients describe the sound as robotic or machine-like with a higher-than-normal high-frequency component. The sound is, however, functional and useful for both speech understanding and development.

If a bone conduction device is the best choice for you or your child, you should be clear that revision surgery will be needed in almost 100% of pediatric patients. This is rarely shared by surgeons recommending these devices. Two sources cause the need for revision:

 

• Infection and/or the device coming out. In BCHA devices with a component through the skin (such as the BAHA Connect or Oticon Ponto), local skin infection occurs an average of 2.3 times per year. These are typically easily treatable with gentle cleaning and topical medications but may require revision.
• Extrusion of implantable bone conduction hearing devices happens in 8% of patients. This means the inserted portion of the device will come out.
• As a child grows, both the skin of the scalp and the thickness of the skull increase significantly. (For example, children around five years of age have a skull skin thickness of 4-5 mm and adults have a skull skin thickness of 12-17 mm.) Due to these changes, there is nearly a 100% chance a portion of the implant will need to be changed when a child becomes an adult.

 

The cost of implantable BCHAs may be less than surgery for an ear canal at first. In the long run, the cost of implantable devices is significantly more. External processors are replaced on average every four to five years for life, and each replacement is $5,000–7,000 in U.S. dollars. Revision surgery is inevitable and will also add a financial burden.

Patients with bilateral CAAM should be fitted with bone conduction hearing aids on a headband within the first few months after birth. Surgery is not required for fitting a soft band device and can be performed in a single day in qualified centers. The sound from a headband bone conduction hearing device is not as good as the implanted variety, but it is close enough to normal sound to allow stimulation of the auditory system and speech development. The surface BCHA can be worn until the best CAAM treatment is determined two or three years in the future. Without using this device early and frequently, severe language and word formation effects will occur.

Many patients use a headband BCHA for their first three years before a surgically created ear canal is performed. This approach maximizes the first three years of speech development.

Some parents choose to use a headband BCHA in single-sided CAAM as well. Undoubtedly, the sound from the surface device stimulates the CAAM inner ear and brain pathway. While we believe this will be proven beneficial, not enough data exists at this time to recommend this strategy for all patients. We do know, however, that a headband BCHA must be introduced early (preferably under six to eight months of age) or a child will not accept it. Two- or three-year-olds simply remove the device every time a parent tries to put it on! Conversely, if children use devices from a young age, they accept them as part of their normal lives.

Microtia Repair Options

Two main methods of surgical outer ear reconstruction exist today and are detailed below – rib graft repair and PPE repair. Your choice of technique to reconstruct the outer ear malformation affects the timing of atresia repair if your child is a candidate for an ear canal surgery. Ear canal surgery follows rib graft repair. Ear canal surgery occurs before or at the same time as PPE repair. Consultation with a plastic surgeon adept in the technique is an important and necessary part of treatment planning. Your decision should be made by the time the CT scan is read at 2.5 years of age.

Plastic surgeons usually perform only one technique and can feel rather strongly about which method is best. Expect to receive conflicting information if you talk to different plastic surgeons, especially if they use different techniques. I have tried to give you some advantages and disadvantages of the different techniques below and to help you know what to ask of your chosen plastic surgeon/s. We remain available to help you sort through different recommendations from different surgeons should you become frustrated or confused.

I advise you to ask how many surgical repairs a plastic surgeon has performed when you have a consultation. It takes quite a number of cases to become good at microtia repair. You should seek to avoid a disastrous result from inexperienced surgeons operating on your child with good intentions.

Be aware that a high percentage of plastic surgeons know little about hearing or the importance of early hearing restoration for speech and language and brain development. (That’s understandable since hearing loss is not a topic of education in plastic surgery training programs.) Consequently, your plastic surgeon may not factor in this aspect of your child’s function and future when recommending treatment. Some plastic surgeons have educated themselves about the effect of hearing impairment on their patients and do a good job considering it in treatment planning. In my experience, it is best to consult your otologist regarding any advice given by a plastic surgeon about hearing.

The malformed portion of the outer ear is sometimes called the pinna. Three options for reconstructions exist:

 

• External prosthesis
• Rib graft implant
• Porous Polyethylene Implant (PPE) (MEDPOR, Supor)

 

Differences between techniques are outlined briefly below. You must select a method of outer ear reconstruction before you can make the final plan for hearing.

Comparison of Outer Ear Reconstruction Options

	When outer ear procedure begins	Number of surgeries required	Kind of surgeon needed for outer ear procedure	When ear canal surgery can occur
External prosthesis	Any age	None	Prosthetics specialists	Before or after fitting. An external prosthesis can be made to fit around the ear canal.
Rib graft implant	Five or six years	Three to four	Plastic surgeon	After (upon completion of outer the series of three to four ear surgeries)
PPE implant	Three years	One	Plastic surgeon	Before or at the same time

 

Worldwide, more patients receive rib graft implantation than other techniques. Rib graft repair has been around since the 1960s, and more surgeons are familiar with it. Over the past decade, however, there has been a shift away from the traditional method of microtia repair in centers of excellence like ours. More parents select PPE implantation than rib graft implantation in our patients. Few patients use an external prosthesis unless they aren’t candidates for surgical reconstruction. Examples where prostheses are a good option include missing ears, burned ears, or in ears that lack the tissues necessary for successful reconstruction (as determined by a plastic surgeon).

Almost always, different surgeons are required to perform atresia repair and microtia repair on each patient. For best results, seamless coordination and communication are needed between these teams. Without it, one surgeon can make another surgeon’s job difficult or impossible. For example, if jaw surgery is done before microtia surgery and the artery needed for outer ear reconstruction is damaged, PPE implantation can be difficult or impossible, and a different technique may have to be used.

I work with surgeons who use each technique. Frequently, parents ask my objective opinion of the three techniques. By describing each, and listing the major advantages and disadvantages of each, I hope to give you some assistance in selecting your own best choice.

External Prosthesis

What Is It?

An outer ear model can be made of rubbery plastic. It is extremely realistic and can match an existing ear nearly identically. To get a sense for the technology, imagine a Hollywood movie where costumes and amazing effects are created.

An example of an outer ear prosthesis, held in position by glues.

How Is It Used?

Users wear the prosthesis each day and remove it each night. The device remains in place over the existing microtia ear or around a created ear canal. Two methods are used to secure the prosthesis. Glues are the most common method. Alternatively, magnets can be used to hold the external prosthesis in the correct location. The magnets require a surgical procedure to place them. After healing, the external prosthesis is created with corresponding magnets to hold it in position.

Advantages

• Can provide reconstruction when surgical options are not possible
• Provide the most realistic and lifelike reconstruction

Disadvantages

• Can fall off during wear and expose the underlying ear malformation
• Daily applications can be time consuming and difficult
• Natural skin tones change with the hot and cold seasons, so at least two different suntan shades are usually needed.
• Due to wear, damage, or loss, multiple prostheses will be necessary during a patient’s lifetime

Rib Graft

In rib graft surgery, a portion of a rib is removed from the chest wall to construct an ear form. This form is then implanted under the existing skin of the microtia ear after removal of the malformed cartilage tissue. One or two ears can be constructed using the rib graft technique. A sufficient rib from one side of the anterior chest is used for each ear.

For rib graft outer ear reconstruction, rib cartilage is harvested from the anterior chest wall and used to create a custom scaffold for implantation under the skin.

Children must be at least five or six years of age, or even older if they have small bodies, for enough cartilage to be present to construct an ear. Three or four stages of reconstruction are performed, each with its own surgery.

 

1. The first is the removal of the rib and the creation and implantation of the ear form.
2. The ear lobe (which is usually relatively normal but in the wrong position in a microtia ear) is moved to the correct position after the cartilage implant heals.
3. The ear is lifted with a skin graft behind the cartilage to help the ear project away from the head and match the opposite side.
4. Some surgeons add a fourth reconstruction to add a tragus, which is a small piece of cartilage normally located in front of the ear canal. Some surgeons perform this step during the third surgery.

A diagram of the normal anatomical landmarks of the outer ear.

Ear canal reconstruction must take place after rib graft surgery for the rib graft technique to heal appropriately. (See Atresia Repair Surgery below.)

Each stage requires healing before the next surgery can be performed. On average, Global Hearing’s patients who select rib graft surgery average 3.6 surgeries before an ear canal is created. Our average age for ear canal creation with ear rib graft microtia repair is 11.6 years.

As you know from the critical period of development section above, 11.6 years is beyond the period of normal development of important portions of hearing, such as speech and language. If rib graft microtia repair is selected, it is important to stimulate the ear being reconstructed with a bone conduction hearing device (a description of this technology is below) until the ear canal is reconstructed.

Advantages

• Since rib is our own tissue, reaction to the material is minimal. This technique avoids the use of foreign material in the body. The new ear is effectively a transplant of the patient’s own tissue, and there is little risk the body will not accept it or heal well.
• The rate of implant exposure—in other words, when the implant protrudes through the skin and makes another surgery for removal and replacement necessary—is 1% for patients.
• More resistant to traumatic injury than PPE. Both techniques can suffer injury, which may require revision surgery.
• Rib graft surgery does not limit the activities of a patient.
• The reconstructed ear has a better sensation on the ear and surrounding skin. Because rib graft does not require the dissection of tissue from under the scalp, the risk of hair loss or scalp thinning is not present.
• It is rare to have to replace a rib graft implant.
• Infection around surgery is less than 1% of cases.

Disadvantages

• Due to the extended schedule of rib graft surgery, outer ear reconstruction is not accomplished until after the age that other children often tease others for how they look physically.
• Multiple surgical procedures are difficult and can be psychologically challenging for children through early teenage years.
• Scarring and pain are an impact of harvesting cartilage from the chest wall.
• Since rib graft microtia surgery must be completed before ear canal surgery, hearing is not restored until after ten years of age, when the critical period of hearing and speech development has passed. We have seen a difference, particularly in hearing in noise, in patients who have had hearing restored later. These patients are left with permanent hearing and functional deficits. It is possible to minimize, but not alleviate, such effects by using a bone conduction hearing aid until the hearing is restored.
• Compared to PPE, a rib graft has a less normal appearance. This is mainly because the ears made with rib graft are usually situated against the head and do not project like a normal ear. From the side, they can be natural. From the front or from any other angle, it is clearly abnormal.

An example of a patient with unilateral right CAAM after outer ear reconstruction with rib graft. Note the lack of natural projection away from the head, compared to the normal left ear.

• The rate of narrowing of the ear canal after ear canal surgery (called stenosis and described below in the section on ear canal repair) is higher with rib graft versus PPE implantation.
• Rib may resorb over time, causing the implant to decrease in size or to deform

Porous Polyethylene Implantation (PPE)

Surgical reconstruction is accomplished with a man-made material designed for implantation. The material is constructed with a porous design, so blood vessels and tissue grow into it as it heals. The material is made by at least two companies and comes in two pieces. The pieces are welded together in the operating room to create an ear of the shape and size desired. The PPE implant is then placed in the desired position.

PPE ear implant under construction sized to a template drawn to match the normal opposite ear.

A tissue membrane normally situated between the skin of the scalp and the bone of the skull is dissected free during surgery and left attached to its blood supply just above the normal ear. The membrane is placed over the PPE implant, and a suction is used to shrink wrap the membrane onto the PPE implant. Skin grafts are taken from other body portions and sewn together over the membrane flap. Then they are also suctioned onto the membrane flap’s surface to cover the PPE implant. The membrane flap’s blood supply provides oxygen to the skin grafts until after they heal, as the arrangement creates a lining of living tissue.

The overall steps of PPE microtia repair. First, a template is made (if applicable) from the opposite ear, which is used to customize the PPE implant. A tissue flap is dissected and brought down to cover the implant, holding it in place. Finally, skin grafts are used to cover the newly constructed ear.

Ear canal surgery can be performed before PPE reconstruction or at the same time. (See Atresia Repair and Combined Atresia Microtia Repair sections below, respectively.) Ear canal healing should be allowed for a minimum of four months (six months of separation is ideal) before undergoing PPE reconstruction if your treatment plan includes separate surgeries. Ear canal reconstruction after PPE puts the PPE implant at higher risk. While we have performed canal surgery after PPE implantations in a few select patients, we recommend against this approach due to increased risk of complication to the PPE implant.

Advantages

• Since PPE implantation does not rely on the tissue surrounding the ear canal to heal correctly before addressing the ear canal, the canal surgery can be performed before or at the same time as PPE.
• When performed as early as three years of age, PPE allows hearing restoration and normal hearing development during the critical period, while also addressing the aesthetic concerns of microtia and atresia.
• PPE implantation can be and is usually accomplished before school age, when looking different from classmates is an issue.
• On average, 2.6 fewer surgical procedures are required for PPE than for rib graft implantation. This is less challenging psychologically and physically for children, for obvious reasons.
• The best PPE implant results are superior to rib graft implant results in mimicking normal ears. Mainly, this is due to how the reconstructed ears project from the skull to match the other ear from any angle.

This patient had unilateral right CAAM and elected to have the outer ear reconstructed via PPE implantation. Notice the excellent symmetry of the ears, especially with regard to projection of the ear from the head. (Compare to the previous rib graft image.)

• PPE implantation is more easily coupled with an ear canal. Some rib graft implants can be incorrectly placed over the area where the ear canal ought to be. Since the ear canal should always be created either before or at the same time as PPE, we do not see the PPE being placed incorrectly over the ear canal.
• The rate of narrowing of the ear canal is lower with PPE implantation compared to rib graft implantation.
• PPE implantation and canal surgery can be performed in a single outpatient procedure, minimizing the number of surgeries without compromising excellent outcomes. We are currently the only team worldwide doing combined atresia and microtia repair in a single procedure (the CAM procedure).

Disadvantages

• PPE is as good a material as we currently have for implant construction. Nonetheless, it is still a foreign material, and problems can occur. The implant comes through the skin in 4% of patients. Usually, this occurs in the early postoperative period but may happen later as well. If this occurs, the implant can be covered with a small surgery that repositions local tissue. Rarely, a more significant surgery is needed to remove the implant and allow the skin to heal. In this case, the implant then needs to be replaced with a later surgery.
• The PPE is more apt to break with a blow to the ear. The framework that is surgically welded in the operating room can separate, causing a loss of form and/or a problem with the tissue over the PPE implant. This is rare but may lead to a revision surgery with implant replacement.
• Infection rates around surgery are higher with PPE than rib graft. However, this infection rate is still low, involving less than 1% of cases.

 

The cosmetic appearance following microtia reconstruction is important to your choice. It can avoid significant psychological and social consequences for your child. However, experience has also taught me that, the older your child becomes, the more important their hearing function will be—both to them and to you. It’s up to you to consider hearing, development, and future function in your decision-making process.

 

Hearing Results Following Surgery

Expected hearing outcomes can be understood by correlating the chance of success based with a CT scan score. In children who have a CT score of 5 or better, a high percentage (>95%) of children have improved hearing. The hearing can be partial or can even return the hearing to the normal range. It is important to understand that even the best results of atresia repair surgery do not return the hearing to the level of a normal ear, but it can come close. Following surgery, the brain uses the data from the ‘new’ ear and integrates it with the normal signal coming from the unaffected ear in cases of unilateral CAAM. In cases of bilateral CAAM, the hearing levels frequently allow children to stop using devices such as the soft band BAHA or Ponto, permitting them to live device-free.

Analysis of our surgical cases has produced the following data. Patients who have a CT scan score of 8–10 have the highest chance (80%) of reaching the normal range of hearing, which is defined as 0–30 dB on the audiogram. In other words, 8 out of 10 patients with scores in this range will achieve hearing in the normal range. The remaining 2 out of 10 patients have high odds of hearing being improved but hear outside the normal range in that ear. Patients with a score of 6 or 7 also have a good chance (67%) of reaching the 0-30 dB goal for hearing. Again, note that some patients who do not reach the 0-30 dB range can frequently have a middle ear bone repair performed as a second surgery to elevate the hearing to normal ranges. In our patients, a second surgery has been necessary in 6% (or 1 in 17) of cases. If the hearing does not reach 0-30 dB, other methods of supplying hearing to the ear are available to us, including use of air conduction hearing devices as discussed previously in this book.

Children with a score of 5 have just under a 50% chance of reaching desired levels. Scores of 4 or less rarely allow significant improvement in hearing. This is the reason we do not recommend surgery with CT scores of 4 or less.

Hearing outcome based on CT scan J-score. The dark blue percentages shown are the fraction of patients in each category who achieved hearing in the normal range of 0-30 dB after canal surgery. The light blue percentages represent patients whose hearing was outside the 0-30 dB range. Still, almost all patients have improved hearing overall after canal surgery.

Future Considerations

I believe the future is bright for a revolution in microtia repair. New biomaterial techniques use the patient’s own tissue to create an ear that is more realistic in texture and shape. For example, some companies are working on material that is 3D printed. In this way, an ear can be hyper-customized. Say, for example, your child has single-sided CAAM. Their reconstructed ear can be matched nearly exactly to the existing ear. Or, if your child has bilateral CAAM, perhaps their ears can be the same shape as yours!

Currently, both rib graft implants and PPE implants are stiff and do not bend. If a material can be made of the patient’s own tissue and can be made more flexible, the ear may look more natural and, importantly, may be more resistant to trauma. This strategy will also reduce the exposure rates seen with PPE, as the material is not foreign and will be more biocompatible.

I predict the PPE implant surgical technique will continue and will be used to implant newer, better biomaterial outer ears in the next 3–10 years. While that is exciting, it creates other issues. For example, how long would you want to see data from patients with these newer implants before we can assume the technique holds up over time? What sort of late complications are there, AND how does it look after 10, 20, or even 30 years? At this time, we have more than 50 years of history with rib graft implants and more than 20 years of history with PPE implants. Still, it is exciting to see a new and better way on the horizon.

One common question is, “Can we reconstruct our child’s ear canal and wait for outer ear technology to improve, and if so, how long should we wait?” Yes, if an ear canal is created, the outer ear reconstruction can wait for years. Some patients are currently choosing to have an ear canal only made in small children to enjoy the benefits of auditory and brain development during the critical period. They plan to observe the rapidly evolving technology of outer ear reconstruction before having surgery for the microtia component of CAAM.

Also, we have an adequate amount of experience now to know replacement of PPE implants is not a terribly difficult operation. When a PPE implant breaks, it is replaced by making a vertical incision and opening the skin pouch around it like a clam shell. The new implant is then inserted and the skin is closed. The incision heals quickly and beautifully in almost all instances. I see no reason an existing PPE implant could not be removed and replaced by new material of the exact same size in the future, should one become available.

Another potential combination of techniques may prove to be rib graft implantation following primary ear canal surgery, when canal surgery is performed first using a minimally invasive approach known as micro-incision canalplasty. This technique minimizes scarring around the site of the surgically created canal. Since the skin around the ear canal is not disturbed, this technique may permit placement of a rib graft in a second surgery later, allowing canal reconstruction to occur prior to rib graft surgery.

Treatment Decision Algorithm

This algorithm has proven helpful to parents in understanding their decisions regarding CAAM treatment. As you have now read about much of the information included in the algorithm, it should make sense. Note some small deviations in the algorithm’s order are needed for some patients, and a personalized plan is always recommended. If you understand this, you are well on your way to understanding treatment decisions and choices for CAAM!

A road map to treatment plan options based on CT scan score.

Special Conditions Some CAAM Patients Have

Partial Ear Canal

Development of the ear canal begins within the first few weeks after conception. It’s possible for the process to stop before it is fully complete. Most often, complete atresia (absence of the ear canal altogether) is the most common abnormality. In a small percentage of cases, however, the partial completion of development results in a partial formation of the ear canal.

Partial ear canals may be a short canal that is visible from the exterior but does not fully extend to an eardrum or may be partially present deep within the skull base without a connecting opening to the exterior. There may even be a partial eardrum present. In general, these patients can get some of the best hearing outcomes from surgery. However, the surgical procedure is harder than a complete atresia. Surgeons have to work around the present skin and other tissues that must be preserved. CT scans are necessary to evaluate partial canal development and for planning appropriate treatment. It is important to note that cholesteatomas occur at a higher rate in partial canal development than in complete atresia patients.

Cholesteatoma

As the ear canal and outer ear form in utero, the process can malfunction and produce a cyst of buried skin called a cholesteatoma. The trapped tissue forms a tumor either in the soft tissue around the malformed ear or deeper in the skull bone. The tumor is not cancerous but can cause significant damage if not removed. Over time, cholesteatomas grow and cause bone erosion around them. With enlargement, these destructive lesions can erode into the ear structures, such as the middle ear bones and facial nerve. Possible effects include facial paralysis, loss of hearing function in the involved ear, or severe balance disturbance. In advanced cases, the enlarging mass may erode into the brain cavity and threaten life. In some patients, cholesteatomas become infected and damage surrounding structures. Fortunately, this condition only occurs in a small percentage of cases. We must, however, rule out the presence of a cholesteatoma or patients who are at high risk for developing one in all cases as part of our evaluation.

Not all cholesteatomas can be diagnosed by examining the external microtia ear malformation. In some cases, a cholesteatoma can be present with no external signs whatsoever. It is also important to note that in some patients, a cholesteatoma can go undetected (until a complication occurs) if outer ear surgery is performed without first evaluating a CT scan for the presence of a tumor. Because of this, a CT scan is an essential part of evaluating patients with atresia and microtia.

For this reason, all CAAM patients should have a CT scan before any microtia or atresia repair surgeries are done.

CT scan of patient with right-sided cholesteatoma (indicated by the red arrow). If present, cholesteatomas must be removed before any type of ear surgery is performed!

In some cases of small ear canals, creation of an outer ear can increase the chance a cholesteatoma will develop from a partially formed ear canal. An experienced otologist needs to make that decision, not a plastic surgeon. In other cases of small ear canals, an outer ear can be created with a low risk of cholesteatoma induction.

A cholesteatoma after removal in the operating room. Note the visible skin lining of the tumor.

Please insist on a CT for your child! Some of the world’s most experienced outer ear reconstructive surgeons regularly violate this rule and perform outer ear reconstruction without checking for these rare tumors first. Even the surgeons I work most closely with have made this mistake. Again, if you are told that a visual examination alone is sufficient to make sure a cholesteatoma is not present, you are dealing with a surgeon who is not fully aware of these tumors and their consequences.

Each year, I am referred patients who have never had a CT scan, yet had growing cholesteatomas that caused severe complications. In addition to being a threat to function and life, the presence of an undiscovered cholesteatoma under a microtia reconstruction (via rib graft or PPE implant) may lead to loss of the outer ear. Since plastic surgeons do not ever read CT scans with CAAM, a qualified otologist must review a CT scan from every patient prior to any type of surgery, even if an ear canal is not planned. I suggest strongly that an otologist who knows to look for these congenital tumors read your child’s CT scan. Even radiologists, who specialize in reading X-rays and CT scans, rarely know these tumors exist and frequently miss them when reviewing scans of patients with CAAM.

Cholesteatomas are easily missed at the time of outer ear reconstruction. I have dealt with this complication from some of the world’s best plastic surgeons who specialize in CAAM who either don’t understand the entity or sometimes choose to ignore it. I also have received calls directly from the operating rooms of multiple other surgeons who have discovered this unsuspected tumor while in surgery and don’t know how to deal with it. If an unsuspected tumor is found during microtia repair, the surgery should be stopped and an experienced otologist enlisted to remove the cholesteatoma before proceeding. Since an experienced otologist is usually not available at a moment’s notice to go to the OR, a separate later surgery to remove the cholesteatoma is generally required, followed by a third surgery to complete the first stage of microtia repair.

PPE reconstruction was placed over a known cholesteatoma by a surgeon and family who ignored recommendations for cholesteatoma removal. Three years later, the tumor grew under the implant, threatening the child’s life and requiring PPE implant removal.

Cholesteatomas must be removed completely to ensure a child’s safety. Even one cell of tissue left in the tissue or bone of the skull base will grow back and reform a tumor. Otologists use operating microscopes for ear microsurgery to remove cholesteatomas. The tumor frequently extends deep into the bone or neck structures where outer ear surgeons do not operate regularly. Because of this, they should never be removed without an otologist familiar with these structures, and only under an operating microscope. Plastic surgeons do not use microscopes for microtia repair and are unfamiliar with microsurgical techniques. They should not attempt cholesteatoma removal. As with many surgical procedures, the best chance of successfully and permanently addressing this threatening condition is to do the first surgery correctly.

In cases where an ear canal is not possible or is not selected, a cholesteatoma MUST be removed before microtia reconstruction is performed. Cholesteatoma is one of the few CAAM situations that can threaten the life of your child. The condition must be diagnosed before undertaking surgery of any kind.

Canal cholesteatoma that has become infected and has broken through the skin over the mastoid bone. Surgery and antibiotics were required to remove the cholesteatoma and stop the infection.

Fibrous Incudo-Stapedial (IS) Joint

Around 2005, I began using a new technology to look into patients’ middle ears while in the operating room. We always use a powerful surgical microscope for all operations for CAAM. This technology, however—a tiny camera and recording equipment—allowed me to see things I could not see otherwise.

We found something interesting that surgeons had not known for years: the joint between the second and third middle ear bones was formed incorrectly in a significant number of cases (26.7%).

This was the first time this malformation was noted in CAAM patients and published—a situation that may have been responsible for the poor and unexplained hearing results we found in some patients. The medical paper we produced with the help of one of our excellent fellow physicians describing this finding was published in 2014.[xi]

Middle ear bones with commonly affected area of fibrous union.

Can We Improve the Condition?

We set out to determine if we could improve surgical results in this condition. This was a significant step forward in understanding this abnormality present in the middle ear bones of a substantial number of patients. We were the first to discover this issue and, as a result of our findings, made significant progress in finding a cause of poor hearing outcomes in 27% of our patients! For years, surgeons had not known about this anatomic abnormality and, as a result, could not correctly identify the cause of less than optimal hearing outcomes in patients affected by this condition. It turns out the condition was a major cause in many cases when CAAM patients’ hearing did not improve adequately despite successful surgery.

Below, you see the images from one of the surgeries where we found this abnormality.

Abnormal fibrous incudo-stapedial (IS) joint under the microscope.

Normally, the joint between the incus (the second middle ear bone) and the stapes (the third middle ear bone) measures less than 1 mm and is the smallest joint in the body. Because the joint involves bone touching bone with the smallest joint in the body in between, any sound vibration from the eardrum travels to the first middle ear bone (called the malleus), and then to the incus and stapes, and finally into the inner ear. In this example, the joint between the incus and the stapes is not bone on bone but, rather, is composed of a short length of scar tissue. Instead of the firm connection normally present, this tissue is flexible, and a significant portion of energy is lost in vibration. This means that sound waves conducted through the hearing chain are lost at this connection point, and hearing does not reach desired levels.

To determine if we could see this joint on CT scans prior to surgery, we went to our digital repository and reviewed hundreds of scans. We found that it was impossible to be 100% sure of the status of the IS joint based on a CT scan alone. While CT scans are the gold standard for evaluating the bony structures of the middle ear, the reality is that this joint is mere millimeters in size and is too small to identify for certain if the tissue is normal or not based on CT scan imaging alone. For that reason, we only know the status of the IS joint for sure when we see it in the operating room.

How Do We Fix It?

Loss of energy produces a loss of hearing. A better connection between the middle ear bones is needed to achieve optimal hearing. To treat this issue, I developed several titanium prostheses to allow us to “bridge the gap” and improve hearing results in patients with abnormal IS joints. Here you see some of the prostheses which measure only 1–3 mm in size. They are in use today for fibrous IS joint reconstruction. Since the middle ear bones are fully grown at birth, the prosthesis does not have to be replaced as the child grows. They last for life.

 

Various customized middle ear bone reconstruction prostheses.

To determine if we needed to repair all cases of fibrous IS joint, regardless of severity, we performed a study to assess IS joint status and hearing outcomes. This data would help us know when to use these new prostheses and when to leave the joint as is. We noticed some patients had good hearing tests despite having fibrous IS joint, while others did not have as good of hearing outcomes after surgery. Through advanced statistical analysis of our patients’ reconstruction outcomes, we developed the following guidelines:

Normal IS Joint	No reconstruction
Mild Fibrous IS Joint	No reconstruction; wait for hearing test four to five months after surgery to determine if a second surgery is needed
Moderate Fibrous IS Joint	Reconstruct with a prosthesis during the first surgery
Severe Fibrous IS Joint	Reconstruct with a prosthesis during the first surgery

 

In patients who have a mild fibrous IS joint, a good percentage of patients will have adequate post-operative hearing. Other patients enjoy improved but not maximally improved hearing and require another surgery to repair the middle ear bones with the placement of a titanium prosthesis. This applies to 6% of Global Hearing patients. The revision surgery in these cases goes through the newly created ear canal, where the eardrum is lifted and the prosthetic repair is performed. Healing is much more rapid than the first surgery. The research to determine when to replace the joint at the time of the first surgery saves many patients the necessity of having a second surgery.

Hearing results with the prostheses can be great and rival those of normal middle ear bones. In fact, some of our best hearing results are seen with middle ear bone reconstruction. Middle ear bone implants are designed to last a lifetime but, on occasion, can become displaced, requiring revision surgery to replace them and restore previous hearing levels.

 

Hemi-Facial Microsomia (HFM) & Facial Asymmetry

In many patients, the side of the facial structures affected by CAAM will be less developed than the opposite normal side. In bilateral CAAM, both sides of the face may be underdeveloped. The structures affected are the soft tissue of the cheek and face, the jaw, and the midface bone structure called the maxilla.

Hemifacial Microsomia, or asymmetry of the bone and soft tissue structures of the face, is sometimes associated with CAAM.

In most situations, the difference from the normal side is slight. In severe situations, there can be a marked underdevelopment of the affected side. The “M” and the second “A” of the HEAR MAPS grading system indicates how severe the abnormality is.

23% of individuals evaluated by our team for CAAM have a facial asymmetry. Not all of them require treatment.

Severe asymmetry may be classified as Hemi-Facial Microsomia (HFM). Also, one particular syndrome—Goldenhar Syndrome—can present as HFM but also may involve malformations of the kidney, thyroid, lungs, and, occasionally, the spine. Neither HFM nor Goldenhar Syndrome is associated with intellectual disability. Genetic testing is available for Goldenhar Syndrome.

The jaw, midface, and facial soft tissue develop over the first 10–12 years of life, the majority of which occurs during the first 6 years. In patients born with mild asymmetry, the amount of asymmetry can become either more normal or less normal over the first few years of life. Patients born with no asymmetry rarely develop significant asymmetry and never develop severe asymmetry or jaw problems. In other words, children are born with the abnormality or not, and, in some cases, it can get worse with childhood growth. In others, it may improve with time.

Those with severe asymmetry, especially underdevelopment of the mandible, may have compromise of the space in the throat where air passes to the lungs during sleep. Any snoring in a child is abnormal, and a test can be done to determine if these patients suffer from obstructive sleep apnea due to a small airway. The test is called a sleep study (or polysomnogram) and is done overnight. Monitors observe a child’s air passage during sleep.

Surgical procedures can alter the jaw bone and face to correct abnormalities to normal, or near-normal, function and appearance. Craniofacial surgeons perform these procedures.

A member of Global Hearing’s team invented a device that lengthens jaws in certain patients.

Usually, surgery for HFM is delayed until the teenage years, but severe cases may require early surgery. Consultation with a craniofacial surgeon may be indicated if a moderate or severe asymmetry exists. Should you be evaluated by our team, we will advise you on the best course of action. Early surgery must be coordinated with ear surgery, so the tissues and blood vessels needed for the canal and ear reconstructions are not damaged.

CT and reconstructed image with soft tissue showing underdevelopment of the jaw and soft tissues in Hemi-Facial Microsomia. The device at bottom-right is temporarily surgically implanted to lengthen the jaw.

In patients with mild asymmetry, where the jaw bone structure and face do not need to change, a simple procedure can make the face appear more even. Via liposuction, fat can be removed from the abdomen through a small incision in the umbilicus or belly button. This fat is then injected into the soft tissue of the underdeveloped side of the face. Fat grafting can be done more than once if needed. In some cases, surgery to lengthen the bones of the jaw/face can be performed in combination with fat grafting.

Ear Infections

Middle ear infections are known medically as Otitis Media (OM). In this condition, fluid fills the middle ear, often after a cold or viral infection. The fluid becomes infected, and white blood cells come into the fluid to fight the infection. In normal ears, this increase in fluid volume generates pressure in the middle ear and presses on the eardrum, which hurts quite a lot. Most parents have encountered pediatric ear infections, as they are common.

When present, the infection and fluid cause a temporary decrease in hearing by affecting the eardrum, which doesn’t move as well as usual in response to sound. Usually, the fluid begins to clear within a few days after starting antibiotics, and hearing improves. In some cases, fluid remains in the ear and hearing stays low.

Just about every child gets OM at some point. You can reduce its incidence by keeping up with pediatric immunizations, avoiding smoking around the child, and reducing colds (which is a tough thing). We want to treat any ear infections promptly to return the hearing to normal as soon as possible in a normal ear.

Mild ear infection with fluid and bubbles in the middle ear behind the eardrum.

Acute ear infection with pus behind the eardrum, which is bulging outward.

In ears where the fluid stays more than two months, or if infections appear more than three times in one year, we recommend placement of a Tympanostomy Tube (also called a “grommet” or “pressure equalizing tube”). It promotes the removal and healing of any fluid in the middle ear and can markedly reduce the chance of future ear infections. The downside of this surgical procedure is small. Only 1% of patients will have a hole remaining in their eardrum after the tube naturally falls out six to nine months later. In the case of a remaining hole, it can easily be fixed.

Ear with tympanostomy tube in place. The white cloudy areas are scarring present in the eardrum, left over from prior infections. These scars do not typically harm hearing.

Tympanostomy tube placement is the most common procedure in children in the United States and can be performed by virtually any ear, nose, and throat (ENT) doctor or pediatric ENT doctor (also called otorhinolaryngologists). The procedure takes less than 10 minutes to complete under mild anesthesia so that the child will be still and the doctor can work on the ear safely.

Children with recurring OM should be evaluated for enlargement of the tonsils and/or adenoids. These structures can harbor chronic infections or, if enlarged sufficiently, can obstruct the opening of the eustachian tubes. The eustachian tubes bring air to the middle ear. If you’ve ever held your nose and popped your ear, you’ve interacted with the eustachian tube.

Obstruction of the eustachian tube can produce chronic fluid and/or infections of the middle ear. If these structures are abnormal, surgical removal of the tonsils and adenoids is a good idea before CAAM canal surgery. If they grow to problematic sizes after CAAM, which is unusual, they can be removed then as well—usually by an ENT doctor close to your home.

You may be wondering if OM can affect the CAAM ear (or ears). Yes, it can. A health provider can look in a normal ear and see the eardrum. By seeing fluid behind an eardrum and/or infection and redness, we can make a diagnosis of OM. In a CAAM ear, we have no ear canal, nor do we have an eardrum to examine. While a CT can show the presence of fluid in the middle ear, we don’t do CT scans to diagnose OM in CAAM ears. If your child has CAAM and is sick with a fever and your pediatrician cannot find any other source to explain the fever, assume OM is present and treat with oral antibiotics.

Each month, we get emails stating a patient has developed an infection in a reconstructed CAAM ear many months after surgery. Usually, this is an outer ear canal infection affecting the skin of the canal itself—called Otitis Externa (OE)—but it can be OM. The rate of occurrence of OM appears to be the same in reconstructed CAAM ears as it is in normal children and is treated the same. If an infection is present in a reconstructed CAAM ear, ask a local doctor to examine the ear to determine whether the canal (OE) or middle ear (OM) is affected. In OE, germs infect the skin placed in the ear canal, causing drainage from the ear canal. Almost always, this occurs when the ear has not been cleaned enough. If the natural debris produced by the skin graft builds up, germs can thrive. By removing the excess debris and applying antibiotic drops, the infection is almost always eliminated. In OM, oral antibiotics are indicated to treat the infection. Sometimes both oral antibiotics and antibiotic drops may be needed.

Hearing Loss with Single-Sided CAAM

Your early hearing test or audiogram performed by an audiologist should test both ears. If the “good” ear in single-sided CAAM has a hearing loss (as it does in 23% of cases in our worldwide database), it is important to determine the cause, and fix it promptly, if possible.

Even a small hearing loss affects language development in the first three years of life, and potentially permanently. If your child has single-sided CAAM, she or he relies heavily on the normal ear to hear and develop language, until the CAAM ear is brought to functional hearing levels. If this additional hearing loss is present in the ear not affected with CAAM, we may need to add additional treatment to avoid a severe speech and language delay. Consultation with your team should focus on promptly getting the hearing in the “good” ear into the normal range, and on keeping it there as many days a year as possible.

Bilateral CAAM

Worldwide, 10% of patients have bilateral CAAM. These children require bone conduction hearing devices on a headband to hear as early as possible. Several types of these devices are available around the world. Not all of them are good quality nor do they all produce good hearing and speech development. Global Hearing fits such children within a few weeks of birth. By stimulating the inner ear in this way, speech can develop, and the brain begins development as well.

When CAAM is present in both ears, the HEAR MAPS evaluation score and treatment algorithm is determined for each ear individually. Usually, both ears have the same amount of development, CT scores, hearing test results, etc., but not always. As treatment plans are put together, special considerations are made to reduce the number of treatments.

Remember, surface bone conduction devices (such as the soft band BAHA or Ponto devices) must be started early in life, or irreversible developmental abnormalities will result.

Sleep Apnea

When a person’s airway is too small, an inadequate amount of air passes into the lungs when they sleep. This can cause a dangerous condition that leads to poor growth and development and can affect ear function as well.

Any snoring in a child is abnormal and should be investigated. Children with CAAM are at higher risk of sleep apnea due to small jaws, enlarged tonsils, and enlarged adenoids. Correcting these abnormalities will help these children grow and function normally and will create better outcomes for ear surgery.

An otorhinolaryngologist (or ENT physician) can evaluate your child for sleep apnea. In many cases, an overnight sleep test is done in a center to study the air movement during sleep and to help evaluate for this condition. Note also that large tonsils and adenoids can cause recurrent ear infections and middle ear fluid, as well as sleep apnea.

Your local ENT surgeon may evaluate your child for treatment. First-level treatment includes removal of the tonsils and adenoids. Sometimes, a larger airway is needed, and a craniofacial surgeon may become involved if tonsil and adenoid removal do not solve the issue.

Facial Nerve Weakness

In rare situations, the facial nerve on the side of CAAM is weak, and facial expressions can be affected. Usually, this condition implies a more severe abnormality of inner ear structures, as the facial nerve runs through the inner and middle ear. Otologists are the medical professionals that treat facial nerve conditions.

A CT scan is still necessary for these patients, and some patients are nevertheless candidates for canal surgery. However, a weakness of the facial nerve makes it more likely a patient will have a low CT score and not be a candidate for a canal. Some patients with facial nerve weakness are good candidates to have an ear canal created, with excellent results. As you would expect, should canal surgery not be an option, other methods for getting hearing to an ear also remain possibilities. Usually, the facial nerve can be seen on a CT scan, and its position can be mapped. If the facial nerve is in the path where an ear canal would be created, it can be a reason not to do surgery. Careful attention is always paid to the facial nerve, but extra care must be used if the facial nerve is in a high-risk position.

Some surgical techniques can improve facial nerve function in some patients. Overall, most cases of facial nerve weakness are better left as they are at birth. In some situations, special care of the eye may be needed if the eyelid does not close well. Customized planning is needed by an otologist if this condition is present.

Mixed Hearing Loss/SNHL

In a small percentage of those born with CAAM, a “mixed hearing loss” is present. This term is used when the hearing loss is a mixture of two different types of hearing loss: a conductive loss caused by the absence of an ear canal, PLUS a sensorineural hearing loss caused by weakness of the hearing nerve. A hearing test will show the condition of the inner ear hearing nerve and is critical to evaluating the potential to hear with the creation of an ear canal. If the hearing nerve weakness is too great, an ear canal may not be worth pursuing. If the hearing nerve loss is mild or moderate, a canal and hearing aid after healing from surgery may be the only option for good hearing in the ear.

 

 

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