非含水性ソフトコンタクトレンズによる兎眼症の治療

Treatment of lagophthalmos with hydrophobic soft contact lens

　Butylacrylateとbutylmethacrylateの共重合体を素材とする非含水性ソフトコンタクトレンズ（以下SCL）を兎眼症の患者に装用させた。症例は顔面神経麻痺7例，橋出血2例，筋力低下2例，術後瘢痕1例である。連続装用を原則とし，装用中は点眼を併用し，数日ごとに洗浄を行った。ほとんどの例で症状が改善した。兎眼では瞬目が不完全なため涙液動態が不良であり，眼瞼の支持力低下が多く，ベースカーブやサイズの決定は容易でなかった。レンズの固着や汚れ，異物感などの問題があり，装用を中止したものが4例あった。非含水性SCLは眼球表面からの水分蒸発を防ぎ，乾燥しても形状が変化しないという点で，兎眼症においては含水性SCLに勝ると考えられた。

We treated 14 eyes in 12 cases of lagophthalmos with hydrophobic soft contact lens made of a copolymer of butylacrylate and butylmethacrylate. Lagophthalmos was due to facial palsy in 7, pontine hemorrhage in 2, amyotrophy in 2 and cicatricial eyelids in 1. The soft contact lens was worn as extended wear and was cleansed every few days.

Symptoms of lagophthalmos alleviated in the majority of cases. Determination of proper size or the base curve was difficult because of defectivetear secretion and akinetic eyelids. There were occasional instances of adhesion of the contact lens to the cornea, soiling or irritation. Contact lens wear had to be discontinued in 4 cases.

Hydrophobic contact lens was judged to be supe-rior to hydrophilic one for lagophthalmos. It pre-vents evaporation of tear fluid beneath the contact lens and does not change in shape under the dry condition.