陳旧性外傷性低眼圧黄斑症1例の視機能と術後回復

Recovery of visual function following surgery for persistent hypotony maculopathy secondary to traumatic cyclodialysis

　43歳女性が左眼視力低下で受診した。13か月前に飛入した石で左眼が受傷した。左眼矯正視力は0.7，眼圧は7mmHgであり，部分的毛様体解離があった。左眼は陳旧性低眼圧黄斑症の所見を呈した。全視野ERGは正常であったが，黄斑部局所ERGは，a波，b波，律動様小波がいずれも健眼の約50％に低下し，頂点潜時が延長していた。これらの所見から，黄斑部の視細胞レベルに機能障害があることが推定された。強膜短縮術により眼圧は正常化し，矯正視力は1.2に回復し，電気生理学的所見の左右差がほぼ消失した。外科的治療により，陳旧化した低眼圧黄斑症での視機能が回復しうることを示す症例である。

A 43-year-old female was referred to us for impaired visual acuity in her left eye. She had had suffered blunt trauma in the left eye by a flying piece of stone 13 months before. Her left eye showed corrected visual acuity of 0.7, intraocular pressure (IOP) of 7mmHg, and partial cyclodialysis. Funduscopy showed persistent hypotony maculopathy in the affected eye. Full-field electroretinogram (ERG) was normal. Focal macular ERG (MERG) showed reduced amplitudes in a-wave, b-wave and oscillatory potential to about 50% of those in the fellow eye. The peak latencies were also delayed. The findings were suggestive of impaired function at the level of photoreceptors in the macular area. Scleral shortening induced normalized IOP, improved visual acuity to 1.2, and recovery of electrophysiological visual function to that of the fellow eye. The findings illustrate that surgery may induce recovery of visual function in persistent hypotony maculopathy.