[Giant osteoid osteoma of the posterior skull base. A case report and literature review].

BACKGROUND

Osteoid osteoma is a benign bone neoplasm which is seen in the long bones. It is rarely described in the cranium. Posterior skull base osteoma is extremely rare and has been anecdotally reported.

OBSERVATION

We report a rare case of a large osteoid osteoma of the petro-occipital area in a 26-year-old man. He presented with clinical sign of raised intracranial pressure, cerebellar symptoms and large left retro-auricular swelling. Cerebral MRI shows a giant lesion of the posterior cerebral fossa with destruction of the left petrous bone and the left side of the occipital bone. Large excision was performed through a retro-sigmoid approach. In our knowledge, there is no similar case reported in the literature to date.

CONCLUSION

Although benign and rare, osteoid osteoma can present with neurological deficit due to mass effect and involvement of nervous structures especially in the posterior skull base.