Understanding Microtia Hearing Loss
Microtia is a congenital deformity affecting the external ear, where the ear may be smaller than normal, partially formed, or completely absent. Microtia occurs in roughly one out of every 8,000-10,000 births. Hearing loss is a common condition associated with microtia due to the lack of the external ear canals or middle ear structures. This article aims to shed light on microtia hearing loss and its possible connection with Treacher Collins Syndrome.
Cause and Nature of Microtia Hearing Loss
There are three common types of hearing loss: conductive, sensorineural, and mixed hearing loss. Microtia often causes conductive hearing loss, which results from problems with the ear canal, eardrum, or middle ear and its tiny bones (the malleus, incus, and stapes).
For a person with microtia, the external ear canal is typically absent, partially closed, or significantly smaller than usual. This abnormality often extends to the middle ear, causing additional issues with the small bones responsible for transmitting sound to the inner ear. Although the inner ear remains unaffected, the path for sound to reach it is disrupted, causing hearing loss.
Symptoms and Diagnosis
Microtia is noticeable at birth due to the visible abnormalities of the outer ear. However, the associated hearing loss may not become apparent until the child is older. The child might face difficulties responding to sounds, understanding spoken words, maintaining attention, and developing speech and language skills.
For diagnosis, a pediatric audiologist will usually conduct a series of tests, including an auditory brainstem response (ABR) test and otoacoustic emissions (OAE) testing, to diagnose the extent of the hearing loss.
The exact cause of microtia is still unknown, though it is often associated with certain genetic conditions, such as Treacher Collins Syndrome. Treacher Collins is a rare, genetic disorder characterized by deformities of the eyes, ears, cheekbones, and chin. Often, these children may require treacher collins surgery to rectify facial deformities.
Treatment Options
Microtia hearing loss can be managed effectively, and many individuals with the condition lead normal, productive lives. Treatment procedure may involve the use of hearing aids, bone-conduction devices, or reconstructive surgery.
Children with microtia are typically good candidates for bone-anchored hearing aid (BAHA) or bone conduction hearing device (BCHD) since the inner ear usually develops normally. In severe cases, reconstructive surgery to build an external ear and open up the ear canal may be considered.
Conclusion
Though microtia and the associated hearing loss present significant challenges, modern medicine offers several avenues for improvement. These range from minimally invasive treatments like BAHA, BCHD to complex treacher collins surgery in associated cases. With early diagnosis and the right treatment plan, children with microtia can overcome these obstacles and lead fulfilling lives.