We report on a case of hemi-central retinal vein occlusion (Hemi-CRVO) which occurred in a patient with Type 1 neurofibromatosis.

A 31-year-old woman presented with a chief complaint of a one-month history of decreased visual acuity in the left eye. The patient had Type 1 neurofibromatosis but had no other systemic diseases. The best corrected visual acuity (BCVA) was 0.8 in the right eye and 0.05 in the left eye. Multiple Lisch nodules were present in the irises of both eyes on slit lamp examination. Fundus examination revealed a hemi-central retinal artery occlusion in the left eye. Optical coherence tomograms showed that the central macular thickness was 192 microns in the right eye and 732 microns in the left eye. There was cystoid macular edema in the left eye. A fluorescein angiogram showed delayed filling in the superior branch retinal vein of the left eye. There was an extensive area of non-perfusion of the retinal capillary in the corresponding area, including the perifoveal area. Blood tests for hyper-coagulability, autoimmune disorders, connective tissue disorders and other tests for the brain and carotid artery and coronary artery disease showed no abnormal findings. The clinical course was monitored following an intravitreal injection of bevacizumab (Avastin®). Eight months later, the BCVA had improved to 0.2.

Although it is rare, hemi-CRVO occurring in younger patients who have no underlying diseases could be related to neurofibromatosis.