小切開白内障手術における耳側角膜切開および耳側強角膜切開の術後2年間の角膜乱視変化

Two-year changes in corneal astigmatism after small-incision cataract surgery through temporal clear corneal and temporal sclerocorneal incisions

（D−8PM−6）　3.2mm耳側切開による無縫合白内障手術後2年間の角膜乱視変化を，角膜切開20眼と強角膜切開20眼で比較した。軸乱視量，惹起角膜乱視絶対量ともに強角膜切開のほうが小さく，術後1年目まで角膜切開との間に有意差が認められた。術後2年目の惹起角膜乱視絶対量は，角膜切開で平均0.42（±0.24） D，強角膜切開で0.32（±0.20） Dであった。術後角膜形状変化は，強角膜切開では切開創の軽微なフラット化を認め，その後軽減したのに対し，角側切開では早期に大きな切開創のフラット化と直交するスティープ化を認め，形状変化も持続する傾向を示した。3周2mm耳側切開では，両切開ともに軽度ながら術後2年目でも手術による角膜乱視が残存して認められた。

We evaluated the changes in corneal astigmatism during 2 years after sutureless cataract surgery in 40 eyes through 3.2 mm temporal incisions. Surgery was performed through clear corneal incision in 20 eyes and through clerocorneal incision in the other 20 eyes. Both axial and surgically induced astigmatism were less in the latter group. The difference was significant up to one year after surgery. Surgically induced astigmatism averaged 0.42±0.24 D in the former group and 0.32±0.20 D in the latter. By corneal topography, corneal changes decreased after initial slight flattening near the site of sclerocorneal incision. They showed persistent marked flattening near the site of clear corneal incision with vertical steepening from the early postoperative period. Surgically induced corneal astigmatism remained, although slight in amount, 2 years after surgery in both groups receiving 3.2 mm temporal incision.