Boy without an ear canal receives life-changing ENT surgery
Posted on 30 July 2019
After 17 years with no hearing in his right ear, a boy can hear properly – thanks to innovative implant surgery at Mediclinic Louis Leipoldt.
“It is rare for a patient with an absent ear canal to present at Riven’s age of 17. Usually the condition is associated with abnormal formation of the external ear lobe which is easily noticed at birth and because of the cosmetic effect to get attention at an earlier stage. Riven coped with his hearing in only one ear until he presented in his matric year for further evaluation.”
Dr Johan Nell, an ear, nose and throat surgeon at Mediclinic Louis Leipoldt, remembers being surprised when a 17-year-old boy arrived for a consultation at his rooms, having never been able to hear with his right ear. “He had a blind ending ear canal,” says Dr Nell. “This means that while his ear looked normal from the outside, he had no useful hearing in the right ear.”
With no ear canal, the patient suffered from conductive hearing loss on the right side. This condition is commonly known as congenital aural atresia, and occurs when the external auditory canal and structures in the middle ear fail to develop properly before birth.
Usually, this condition poses a significant challenge to ENT surgeons. In fact, typical treatment for this condition is considered one of the most difficult and challenging surgeries in the field. “As far as surgery goes, it can be done – but we’re looking at a difficult, drastic procedure, with long recovery times and unfortunately, in most cases, poor outcomes for the patient.”
The approach has now changed. An innovative piece of technology, known as a Bone Conduction Implant System, promises to change the lives of patients with damaged or under-developed outer and middle ear systems. This is an implantable bone conduction device that can be surgically implanted beneath the skin, allowing sound waves to access to the middle ear directly.
As Dr Nell explains, in most people with functional ear systems, sound vibrations travel through the outer and middle parts of the ear, and on to the inner ear. For patients with conductive or mixed hearing loss, this is not the case – when the outer or middle ear is damaged, sounds cannot reach the inner ear effectively. The Bone Conduction implant works by allowing sound waves to bypass the outer and middle ear systems, sending these vibrations to your inner ear through the bones of the skull.
The Bone Conduction implant consists of two parts: an externally worn audio processor, which picks up sound waves from the environment and sends them to the internal implant, which is placed under the skin behind the ear. The two parts connect via a magnet.
The external audio processor is worn on the head and contains two microphones, a digital signal processor and a battery. The internal implant, positioned in the skull under the skin, consists of a receiver coil, a demodulator and a transducer.
Candidates for this implant are carefully selected, says Dr Nell. “If you have a damaged cochlear, this is not going to help, as that is a whole different condition. But for patients with outer and middle ear systems that are damaged or not fully developed, this is a life-changer.”
The surgery to place the implant is remarkably simple. “We make an incision behind the ear, drill a circular hole into the bone of the skull, and embed the transducer in the skull.” The procedure itself takes anywhere between one and two hours. The processor can be activated as soon as the swelling of the skin has reduced. An audiologist will usually be required to program the audio processor to the patient’s particular hearing needs.
An audiologist plays an important role in selecting patients and assisting them with adaptation of processor after the surgery has been performed. “In this case Liezel Kotze and Eloïse Scholtz from Hearing Balance, in Bellville assisted with the audiometry pre-operatively and with the setting and adaptation in the post-operative phase.”
This technology is unique in that it is an active bone conduction implant that is fully embedded under the skin. “Until now, most of these devices involve some or other part sticking out of the skin,” Dr Nell explains. “Now, that is of course uncomfortable – but also impractical, in that it leads to a higher risk of infection. This one is invisible.”
It is also highly effective. “Four months after surgery, the patient is back to studying, hearing properly, living a new life.”