[Hyperostotic optic canal stenosis caused by mucocele of the posterior ethmoid sinus: a case report].

We reported a rare case of hyperostotic optic canal stenosis caused by mucocele of the posterior ethmoid sinus. A 49-year-old woman presented with progressive right visual disturbance. She had a visual acuity loss, a ring-shaped visual field defect, and a choked disc in the right eye. An X-ray of Rhese-Goalwin's view revealed a right optic canal stenosis. A CT scan also disclosed regional hyperostosis in the right lateral wall of the posterior ethmoid sinus. The posterior ethmoid sinus had a small cystic mass which was diagnosed as a mucocele by MR images. The patient's symptoms recovered rapidly after an operation for the extradural optic canal release through right frontotemporal craniotomy. We supposed that spread of an inflammation by mucocele was able to cause regional hyperostosis in the wall of the ethmoidal sinus, which led to optic canal stenosis.