Hearing loss due to cranio-metaphysial dysplasia.

Craniometaphysial dysplasia is a rare cause of conductive hearing loss. It is a genetic disorder of bone due to decreased osteoclastic activity in the endosteal and periosteal regions of craniofacial and long bones. The characteristic temporal bone abnormalities are attic fixation, abnormally shaped ossicles and obliterated foramina ovale. Computerised tomography is helpful in predicting operative findings; surgery should be reserved for those with a severe hearing loss.