Aneurysmal bone cyst of the petrous bone: case presentation and review of the literature.

Aneurysmal bone cysts (ABC) were originally described by Jaffe and Lichtenstein [Arch Surg 1942;44:1004-1025] in 1942 as nonneoplastic benign lesions with obscure pathogenesis. ABC occurring in the temporal bone are uncommon. Those arising from the petrous portion of the temporal bone are exceedingly rare. We report a right petrous ABC in a 16-year-old girl who presented clinically with hearing loss, facial weakness, and facial numbness and tingling. Her symptoms were preceded by a coincidental traumatic concussion 4 months earlier. Preoperative magnetic resonance imaging and computed tomography findings were both consistent with an ABC, although the lesion was noted to be in a very unusual location. Surgical resection was performed with adjuvant preoperative embolization. The patient recovered complete facial sensation and movement, and follow-up imaging documented complete resection.