MRI visualization of complete bilateral optic nerve involvement by pituitary adenoma: a case report.

With large pituitary adenomas, the optic nerves and chiasm usually lie on the tumour capsule and are displaced superiorly. We report a large invasive pituitary adenoma, with complete involvement of both optic nerves. Review of the preoperative MR images demonstrated the optic nerves, with signal intensity close to that of cerebral white matter, and different from the flow void of the basal cerebral arteries. Correlation of this observation with intraoperative findings is discussed.