The external auditory canal is a kind of channel that connects the outside of the head with the tympanic membrane of the middle ear. Its outer part is lined by cartilage, and its inner part has a bony surface. Exostoses in the external auditory canal affect this bone surface of the specific canal and are benign bone growths. The majority of exostoses remain asymptomatic, however they may cause adverse symptoms such as hearing loss and otitis. In these cases, external auditory canal exostoses removal through surgery is indicated.
What are the exostoses of the external auditory canal?
Exostoses of the external auditory canal are usually multiple, hard bony structures that are mostly bilateral and present slow growth. They consist exclusively of osseous tissue and are sessile. They vary in shape, whether they are round, oval or elongated. They are mostly caused by repeated thermal irritation in the ear area, which occurs when cold water is regularly introduced into the external auditory canal.
When someone is regularly exposed to cold water that enters the ear cavity, they may develop secondary periostitis, a condition that causes exostoses to form. This specific condition is also characterized as winter swimmers’ disease, as it occurs more often in divers and people who dive in icy water. Repeated thermal stimulation encourages the periosteum to produce parallel layers of osseous tissue, which causes the bony portion of the external auditory canal to increase in size.
Exostoses of the external auditory canal symptoms
In case of small size exostoses, there are usually no symptoms. However, large bone growths cause symptoms such as obstruction of the external auditory canal. This can lead to conductive hearing loss, a feeling of fullness in the ear area, retention of water, wax or other debris that may enter the ear canal. Retention of debris such as wax and its entrapment inside the ear due to exostoses can lead to complete obstruction of the external auditory canal near the tympanic membrane.
As the production of wax is important for the elimination of dead cells and environmental pollutants, its entrapment in the area between the exostoses and the eardrum prevents movement of the wax to the outside and proper hygiene of the area. This leads in many cases to the appearance of otitis externa. Repeated and prolonged infections can be the cause of hearing loss. In advanced cases of the condition, where the symptoms make the patient’s daily life difficult, the external auditory canal exostoses surgical removal is necessary.
Exostoses of the external auditory canal diagnosis
In the majority of cases, exostoses remain asymptomatic and they can be detected through a random check of the ear by a qualified otolaryngologist using an otoscope. At the same time, an endoscopy of the external auditory canal can be performed with a flexible endoscope. In case that surgery is necessary, a CT scan is performed pre-operatively which provides a clear picture of the size and extent of the exostoses, which are important data for performing the surgery of the external auditory canal exostoses removal.
At the same time, an audiogram is performed to diagnose conductive hearing loss or some other auditory disorder. Surgical removal of exostoses of the external auditory canal is indicated in cases of recurrent otitis externa, hearing loss, otalgia and other diseases for the treatment of which it is important to remove the specific bony growths.
External auditory canal exostoses removal: Process & Post-operative course
External auditory canal exostoses removal is performed through a surgical procedure known as canaloplasty. This operation involves making an incision behind the ear and extracting bone growths in the temporal bone that have blocked the external auditory canal. ENT Surgeon Athens Dr. Olga Papadopoulou can also perform the surgery through the ear canal itself. The incision is then sutured and the stitches are removed a week later. However, patients should avoid contact with cold water, wind and moisture during the recovery period, which can last from 1-3 months.