中性フィルタを使った黄斑円孔術後視力の評価

Use of neutral density filter in the evaluation of visual acuity after macular hole surgery

要約　初回手術で閉鎖し，9か月以上が経過した特発性黄斑円孔58眼の視機能を検索した。合併症がない他眼26眼を正常群として対照にした。視機能評価には中性フィルタ（neutral density filter：NDF）を用い，濃度80％視力と濃度0％視力の比を両群について比較した。円孔閉鎖群では，中性フィルタで視力が低下する比率が正常群よりも有意に高かった（p＜0.01）。円孔閉鎖群での濃度80％対0％視力の値は正常群よりも低く（p＜0.05），術前視力，年齢，視力改善度と正の相関があった。手術で閉鎖した黄斑円孔眼では，非円孔眼よりも視力の質が低下している可能性がある。

Abstract.　We evaluated the visual function in 58 eyes of idiopathic macular hole more than 9 months after successful surgery. The findings were compared with those in 26 unaffected fellow eyes which served as control. We measured the visual acuity using neutral density filters（NDF）. The ratio of visual acuity using 80％ NDF versus 0％ NDF was calculated for both groups. Use of density filter induced greater decrease in visual acuity in macular hole group than in control（p＜0.01）. The ratio of 80％ NDF vs 0％ NDF visual acuity was less in macular hole group than in control（p＜0.05）This value was positively correlated with preoperative visual acuity,age,and rate of improvement of visual acuity. The findings seemed to show that,even after successful surgery,visual acuity in eyes of macular hole is of lesser quality than in normal eyes.