External auditory canal cholesteatoma

External auditory canal cholesteatoma is characterized by the proliferation of squamous epithelium in the external auditory canal due to various causes, leading to the accumulation of gelatinous debris containing cholesterol crystals. This condition is a well-defined benign cystic lesion that, due to its invasive nature resembling malignant tumors, often causes varying degrees of absorption and destruction of surrounding bone structures. It can occur at all ages, but is more common in middle-aged and elderly individuals, primarily presenting with otorrhea, otalgia, hearing loss, and facial paralysis. External auditory canal cholesteatoma is generally divided into four stages: Stage I: Confined to the external auditory canal with no obvious bone destruction. Stage II: Bone destruction of the external auditory canal, but without invasion of the tympanic cavity or mastoid. Stage III: Invasion of the tympanic cavity and/or mastoid. Stage IV: Invasion extending to external structures of the temporal bone.