Presentation
The patient presented with a longstanding history of progressive mixed pattern of hearing loss
Patient Data
High-resolution CT at the level of both petrous bones shows bilateral areas of lucencies (due to demineralization) involving oval windows, stapes footplates, and fissulae ante fenestram.
Note also the circumscribed areas of demineralization just medial to cochlear basal turns and cochlear apertures bilaterally.
1. First annotated image shows areas of demineralization centered to the cochlear promontory involving oval window and fissulae ante fenestrae (white arrows)
2. Second and third magnified annotated images in the coronal plane of both right and left petrous bones showing the areas of demineralization (white arrows)
3. Forth and fifth annotated images show focal demineralization medial to the basal cochlear turns and cochlear apertures (black arrows)
Case Discussion
The case presented demonstrates the characteristic appearance of fenestral and retrofenestral otospongiosis.
Otospongiosis is the better term to describe early otosclerosis (The active phase of bone dystrophy and demineralization). Later on, osteoblasts activity predominate and dense bone is formed hence the term otosclerosis is the widely used term to describe the condition.