Cholesteatoma is a benign growth that consists of a buildup of squamous epithelial skin cells that grow into the middle ear and mastoid bone. These are benign conditions and are not tumors but can grow with time causing problems because of erosion of the bones inside and surrounding the ear and the base of the skull. These lesions generally grow slowly as the more and more layers of old skin cells and their secretions are deposited within the bone of the ear and skull base. The destruction of the bones of the middle ear will often lead to hearing loss and can rarely extend into the skull base where they can exert pressure onto the brain.
Cholesteatoma usually occur because of poor eustachian tube function and repeated infections in the middle ear. The eustachian tube allows air from the ear to communicate to the nose. When the eustachian tube is blocked because of allergy, anatomic predisposition, or infections a small vacuum can develop which brings in the epithelial skin cells that lead to formation of a Cholesteatoma.
Most patients with a cholesteatoma will have fluid discharge from the affected ear, have a sense of fullness in the ear and this is often accompanied with some hearing loss. Less common symptoms of a cholesteatoma include earache, ringing in the ear, gait imbalance, facial weakness or asymmetry and headache.
Cholesteatoma is usually diagnosed with physical examination by an otolaryngologist (ENT specialist). Oftentimes a hearing test will be also administered to determine the extent of any possible hearing loss and to evaluate the extent of destruction the cholesteatoma has caused. A balance test may also be administered to determine the involvement of the bones in the inner ear and skull base that contain the balance organs. An imaging study of the skull base, usually a high resolution CT scan with 3-Dimensional reconstructions will often be obtained to understand the extent of bony destruction and involvement by the Cholesteatoma.
Initial treatment for a cholesteatoma may consist of a careful cleaning of the ear, antibiotics, and ear drops to help bring any infection under control. A large cholesteatoma usually requires surgery to prevent any further extension of the lesion into critical regions of the skull base. Surgical removal of the cholesteotoma helps to clear any infection and create a dry ear. Sometimes, depending on the extent of destruction, it is possible to attempt reconstruction of the damaged middle ear bones in an effort to improve hearing. If the cholesteatoma has significant extension into the bones of the skull base, including the petrous apex, the lesion might not be adequately drained through a standard outpatient procedure performed through the mastoid bone. Instead, it may require a lateral skull base approach or an endoscopic skull base approach where the lesion is accessed minimally invasively through the nose.