Carotid-Cochlear Dehiscence: A Dangerous Mimicker Of Inner Ear Pathologies

A 67-year-old woman was referred to the otolaryngology service after presenting to the emergency department for dizziness and loss of balance. She reported several similar episodes over the past years. Physical examination was unremarkable. A temporal bone CT scan revealed dehiscence between the bony carotid canal and the cochlea resulting in the diagnosis of carotid-cochlear dehiscence (CCD). CCD is an extremely rare condition involving the thinning of the bony canal separating the internal carotid artery from the cochlea. CCD is best diagnosed with temporal bone CT scan. Treatment options include observation as well as chemical or surgical labyrenthectomy. Despite similar clinical and diagnostic characteristics of reported CCD cases, general trends and consensus on treatment options cannot be ascertained due to the extreme rarity of this condition. Regardless of these limitations, CCD is a critical diagnosis as it mimics other inner ear conditions and poses a potential, significant surgical risk for the otolaryngologist.