Bilateral microtia is a rare congenital condition, characterised by the underdevelopment or complete absence of the external ears on both sides of the head. This anomaly can have a severe impact on the quality of life, notably in hearing capability and personal appearance, therefore, increasing the significance of better understanding and addressing this condition.
Microtia occurs in approximately one in every 8,000 to 10,000 births. It can present unilaterally (one ear affected) or bilaterally (both ears affected), with unilateral cases being substantially more prevalent. Bilateral microtia is especially rare, with reported occurrence in one in every 25,000 births.
Causes and Development
Medical science to date has not yet pinpointed a single cause of bilateral microtia. Many physicians believe it is a multifactorial condition, implying that a combination of genetic, environmental, and potentially random factors during pregnancy may contribute to its development.
The ear formation is a complex process that takes place during the first trimester of pregnancy. Any disruptions during this phase can hinder the ear’s normal development, providing one explanation for the occurrence of microtia.
Implications of Bilateral Microtia
Bilateral microtia primarily impacts the individuals’ hearing, as it often coincides with aural atresia, a condition where the ear canal is narrow or absent. This can lead to conductive hearing loss. However, since most individuals with microtia have intact inner ears, they can often hear well with the help of bone conduction hearing aids.
Besides hearing impairment, people with bilateral microtia often face social and psychological challenges due to the visible difference in their external appearance. This underlines the need for comprehensive care, including psychological support and, where appropriate, reconstructive surgery.
Microtia Surgery for Adults
Most often, treatment for bilateral microtia involves reconstructive microtia surgery for adults. Here, surgeons build a new external ear with a framework usually made from rib cartilage, covered by skin grafts. CNC milled patient specific ear implants have also been gaining popularity as they reduce the need for rib cartilage surgery, and produce consistent surgical outcomes. The surgery typically involves multiple staged procedures to create, position, and refine the new ear. It’s also possible for surgeons to perform canalplasty to build a new ear canal, which, in conjunction with a bone-anchored hearing aid, can improve hearing ability.
Although traditionally phrased as pediatric surgery, microtia surgery for adults has become increasingly common. Surgeons delay surgery until children are old enough for their cartilage to be sufficiently developed and to allow for their input regarding surgery. However, adults who did not have surgical intervention during childhood, should consider microtia surgery for a variety of reasons include improvement in self-esteem, social interactions, and hearing quality.
Bilateral microtia, a complex and multifactorial congenital condition, significantly alters the affected individuals’ life by impairing their hearing and external appearance. Thanks to advancements in surgical techniques, today, comprehensive treatment options, including psychological support and reconstructive surgery such as microtia surgery for adults, are available and are often successful in addressing these issues. Patient-specific treatment plans and consideration for the patients’ overall wellbeing can ensure those affected lead a healthy and fulfilling life.