A case of multiple myeloma presenting with isolated cranial nerve palsy, without the bone pain or renal impairment that usually brings these patients to attention.
Case Presentation
A 62-year-old man presented with six weeks of double vision. Examination showed an isolated sixth nerve palsy. Imaging revealed a clival plasmacytoma; subsequent marrow biopsy confirmed multiple myeloma.
Discussion
Skull-base plasmacytomas are uncommon but worth remembering in any adult with an unexplained cranial neuropathy. Serum free light chains are a cheap and fast first step.
