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Fibrous Dysplasia Causing Conductive Hearing Loss in a Teenager With McCune-Albright Syndrome
A teenager with conductive hearing loss is found to have fibrous dysplasia in the setting of McCune-Albright syndrome.
Imaging overview:
Axial non-contrast CT shows a large, expansile lesion with ground-glass attenuation and heterogeneous internal cystic change, centered in the left maxilla and extending toward the left temporal bone. The arrows mark involvement of the left temporal bone near the middle ear. The lesion is centered in bone and is most extensive in the maxilla.
Clinical insight:
Fibrous dysplasia is a benign fibro-osseous lesion that is expansile and ground-glass in appearance, and it can show heterogeneous cystic change. The maxilla is the most common facial site. Facial involvement is common in polyostotic disease, which is the form seen with McCune-Albright syndrome. Narrowing of skull base foramina from the disease can cause cranial neuropathies, so the skull base should be reviewed on every case. Conductive hearing loss in this setting reflects temporal bone and middle ear involvement, and the diagnosis should prompt evaluation for the other features of McCune-Albright syndrome.
Case courtesy of Alexandra Foust, DO, Vanderbilt University Medical Center.