[A case of cerebellar degeneration showing amaurosis fugax due to primary angle-closure glaucoma].

We reported a 76-year-old woman with cerebellar degeneration who had transient monocular visual loss following the acute attacks of angle-closure glaucoma. The episodes occurred only at night approximately every ten days. She denied pain or any other associated symptoms. Ophthalmological examinations including intraorbital pressure, ocular fundus, visual acuity and visual field showed no abnormalities between the attacks. Provisional diagnosis on admission was amaurosis fugax from retinal embolization. After admission, she developed a typical acute attack of glaucoma accompanied by severe pain in her left eye. Intraorbital pressures were 12 mmHg in the right eye and 58 mmHg in the left, and the diagnosis of primary angle-closure glaucoma was made gonioscopically. Following peripheral iridotomy by laser therapy, her visual acuity recovered and episodes of visual loss disappeared. In this case, the attacks of glaucoma were unusually painless, so it is very difficult to distinguish between glaucoma and amqurosis fugax from retinal embolization. The transient visual loss always occurred at night, and retrospectively, this characteristic feature might indicate that these episodes were acute attacks of angle-closure glaucoma. Glaucoma is one of the diseases that can cause painless amaurosis fugax.