Small or Missing Ears: A Q&A on Microtia and Aural Atresia With Dr. Randall Bly
July 7, 2021
Dr. Randall Bly is an assistant professor of the Department of Otolaryngology – Head and Neck Surgery through the University of Washington School of Medicine, and the co-director of the Cranial Base Program at Seattle Children’s. With a background in mechanical engineering, he also serves as adjunct faculty through the UW College of Engineering. Bly leads a group of surgeon-scientists and engineers at the BioRobotics lab in designing cutting-edge innovations in surgery.
How common are microtia and aural atresia?
Dr. Bly: Microtia is a small or absent ear. About 1 in 5,000 babies are born with it annually in the United States. In most cases, it is only on one side. Seventy percent of these children also lack an ear canal (called aural atresia).
We don’t know what causes microtia in most cases. Sometimes it’s genetic, but no specific gene has been identified. In some cases, it’s related to maternal diabetes during pregnancy, exposure to high doses of vitamin A, or a mother’s use of Accutane (isotretinoin) during pregnancy.
How many patients do you see in a year?
Dr. Bly: We see about 40 new patients each year with microtia and perform over 50 reconstructive surgeries.
What should providers know about the varying severities?
Dr. Bly: There are four classes of microtia, ranging from mild structural abnormalities to a complete absence of the ear. The main thing to know is that, with any type of microtia, the child should have a hearing assessment. Also, the child should be seen by a specialist at least once so the family can learn about all their management options.
What should families consider when choosing a doctor?
Dr. Bly: Families should know their child with microtia will do best with a multidisciplinary team of specialists who will see their child from infancy onwards and address not only the cosmetics of their ear but any related hearing and speech issues, along with any other medical syndromes the child may have (about 10% of kids with microtia have abnormalities in other systems such as facial clefts; heart defects; and eye, kidney or spine abnormalities; the most common condition is hemifacial microsomia). Ideally you want to have a provider team that can offer comprehensive management of the medical issues, hearing loss and outer ear appearance.
It’s not always easy to find such a comprehensive approach, even in urban areas. Most big cities have a facility that offers ear reconstruction, but it’s less common that they can offer coordinated hearing assessment and management too.
What does Seattle Children’s offer?
Dr. Bly: One of the strengths of Seattle Children’s is that we offer all of these things. We have one of the top programs in the country for microtia, offering a multidisciplinary care team that follows patients throughout childhood and presents the family with every option along the way. Our surgeons are board-certified in otolaryngology (head and neck surgery), with two also board-certified in facial plastic surgery. We work closely with the family and their child so they know all the options and the best timing and order of procedures. Without this type of care, kids sometimes end up having more surgeries than necessary and missing opportunities for normal speech and language development, with lifelong impacts.
How does Seattle Children’s treat children with microtia?
Dr. Bly: In the early months and years, we are focused on their hearing. In their first few months, after an initial visit with Lara Clark NP, Dr. Kathleen Sie or me, they receive an audiology assessment and, if needed, a headband with a microphone that sends sounds right into the brain. This is done early because hearing is critical for a baby’s speech and language development. Kids typically wear the headband hearing aid until about age 5, and we closely monitor their speech and language. If the child has other medical issues, like craniofacial microsomia, for example, we bring appropriate specialists into their care.
During the early years, we talk a lot with parents about the timeline and possible scenarios ahead, including reconstructive surgery options or wearing a detachable prosthetic ear that is removed at night. Around age 5, the ear is almost fully grown, and we can use a CT (computed tomography) scan to see if surgery to open the ear canal is likely to improve hearing. We typically wait until the child is 7 years old to offer reconstructive surgery. By this time, parents have taken in a lot of information and usually know which direction they want to go, and the child is old enough to participate in the decision.
Some people argue you should reconstruct the ear sooner, but we feel it is important to empower the patient. It’s really important to us as surgeons that we take the time to show patients and families all of their options, involve the child and support them in their choice.
What specialties are involved?
Our audiologists see these children for testing and hearing device fitting. Julie Kinsman, MA, CCC, is the audiologist who specializes in managing patients who choose devices that require osseointegrated implants.
Kids are seen primarily by our Otolaryngology and Audiology specialists, often on the same day. Speech therapists are also involved to varying degrees to assess how speech and language are coming along. Children with normal hearing in just one ear often develop normal speech and language, but they can also face challenges in these areas.
How do you make an ear?
Dr. Bly: We construct an ear “framework” using either the child’s own rib cartilage or a synthetic material, which we cover with the body’s own tissue. Both make good-looking ears. Carving the framework into an ear takes lots of practice. To hone our skills, we use 3D printings of rib cartilage to train and practice on before surgery. Another one of our training tools is soap carving!
How do the surgeries — cartilage vs. synthetic — compare?
Dr. Bly: There are pros and cons to each.
The synthetic implant surgery is longer by a few hours but only requires one surgery typically. The implant goes in with an incision in the ear area and sometime a separate incision in the scalp. We also need to take a skin graft from the thigh or the other ear. The ear shape is nicely defined but the implant will always be different from the child’s own tissue.
Cartilage has been done for longer, and if there’s ever a skin breakdown or a cut or infection, the body can heal it on its own. It’s done over two separate four-hour surgeries, separated by about three months. The downside is borrowing your own rib cartilage, but the incision we make is less than one inch long and heals well. We also need to take a skin graft, usually from the upper thigh. We typically guide families toward using rib cartilage if we are also going to open the ear canal in order to minimize the risk of infection long-term.
If a child needs a bone-anchored hearing aid, often we place the implant at the same time we repair their outer ear. Doing the procedures at the same time means less time in the hospital for the child overall and fewer procedures to recover from.
How does the new ear look?
Dr. Bly: The reconstructed ear looks like an ear. Up close, people will be able to tell that it looks slightly different than a nonreconstructed ear. They are usually functional, meaning they can support sunglasses or a face mask, for example. We show kids and families pictures ahead of time and try to set realistic expectations. When they come back to see us postoperatively, it can be a really fun thing to see their excitement with their new ear.
Are you doing research on microtia?
Dr. Bly: We’re looking into its causes. Dr. Carrie Heike in our Craniofacial Center is studying the DNA of people with microtia to learn about changes in genes that may cause the condition. She works with researchers here and in South America, where microtia seems to be more common.
We are also conducting research to improve the accuracy of ear reconstruction using a combination of techniques, including 3D printing.