内境界膜剝離後眼底に認めるDONFL様変化の長期経過

Longterm course of findings simulating dissociated optic nerve fiber layer following peeling of internal limiting membrane

　内境界膜剝離を併用した硝子体手術を行い，12か月以上の経過観察ができた65眼中35眼（54％）にdissociated optic nerve fiber layer（DONFL）様の変化が生じた。その内訳は，黄斑上膜13眼中10眼（77％），黄斑円孔33眼中17眼（52％），網膜静脈分枝閉塞症19眼中4眼（21％）である。黄斑上膜と黄斑円孔では，DONFL様変化の有無による視力の差はなかったが，網膜感度はDONFL変化がある群で有意によかった。DONFLの発生率は，術中のインドシアニングリーンの使用の有無と無関係であった。6眼では経過観察中にDONFL様変化が不明瞭になった。観察期間中に，DONFL様変化が視機能に及ぼす影響は認めていない。

　We observed findings simulating dissociated optic nerve fiber layer（DONFL）in 35 out of 65 eyes（54％）that could be followed up for one year or longer after vitrectomy and peeling of internal limiting membrane. DONFL was found in 10 out of 13 eyes（77％）of idiopathic epiretinal membrane,in 17 out of 33 eyes（52％）of idiopathic macular hole,and in 4 out of 19 eyes（21％）of branch retinal vein occlusion. In epiretinal membrane and macular hole,the visual acuity was not influenced by DONFL,but the retinal sensitivity was significantly better when DONFL was present. The incidence of DONFL was independent of intraoperative use of indocyanine green. DONFL-like findings became indistinct in 6 eyes during the course of observation. No untoward effects of DONFL on visual functions have not been detected so far.