Bony trigeminal nerve entrapment in autosomal dominant osteopetrosis: a rare cause of secondary trigeminal neuralgia

Cranial bone disorders are a rare cause of secondary trigeminal neuralgia (TN), producing pain through progressive compression of the trigeminal nerve. We report a 46-year-old man with autosomal dominant osteopetrosis type 1 with left-sided refractory TN. Osteosclerosis of the petrous bone caused medial displacement and bony entrapment of the trigeminal nerve. Through a pretemporal extradural approach, we unroofed the foramen rotundum and foramen ovale, drilled the petrous apex, released the calcified anterior petroclinoid fold and trigeminal fibrous ring, decompressing the nerve along its entire intracranial trajectory. The procedure was completed without complications and produced complete resolution of the TN.