Visual prognosis of optic nerve sheath meningiomas producing shunt vessels on the optic disk: the Hoyt-Spencer syndrome.

Nine patients, including seven women and two men, had meningiomas of the optic nerve sheath. The defect was bilateral in two, in the right eye in six, and in the left eye in one. Most had edema of the disk, and all had progressive loss of vision to blindness in the affected eye owing to optic nerve atrophy. In 10 of the 11 affected eyes, opticociliary shunt veins developed on the optic disk. Exophthalmos was mild and not more than 3 mm in any patient. Ocular movement was mildly impaired in three patients. Indentation and flattening of the posterior pole of the eye was documented in five eyes. Nine of the eleven eyes went on to blindness; one was worse after operation, and the eleventh was lost to follow-up. Surgical treatment has not been effective in these cases or in those reported in the literature.