Optic nerve involvement in the acute retinal necrosis syndrome.

Two patients with acute retinal necrosis syndrome demonstrated enlarged computed tomographic images of the optic nerves, a previously undescribed manifestation of this disorder to the best of our knowledge. One patient, with the bilateral variety of this syndrome, demonstrated bilateral optic nerve enlargement and, in one eye, appeared to achieve visual improvement following an optic nerve sheath decompression. The second patient, with the unilateral variety of the syndrome, demonstrated only unilateral optic nerve enlargement. These observations suggest that the intraorbital optic nerve may be primarily or secondarily involved in the acute retinal necrosis syndrome.