臨床眼科63巻11号

2009年10月発行

特集 緑内障診療―グレーゾーンを越えて Ⅰ．診断編 1．眼　圧

角膜厚とその他の角膜物理特性の影響

著者： 清水聡子¹

所属機関： ¹帝京大学医学部眼科学教室

ページ範囲：P.22 - P.27

はじめに

　現在，真の眼圧を非侵襲的に測定する方法はなく，角膜を介して測定した近似値を臨床的に眼圧としている。角膜を介して眼圧を測る以上，角膜の状態が測定された眼圧に影響を及ぼすことは避けられない。中心角膜厚（central corneal thickness：CCT），角膜曲率半径，角膜弾性，角膜瘢痕，角膜浮腫などが測定値に影響することが知られている。

　近年緑内障診療における角膜厚への関心が高まり，2007年にはAmerican Academy of Ophthalmologyが中心角膜厚は原発開放隅角緑内障の発症・進行の危険因子であるか多数の研究をレビューした論文を発表している^1）。そのなかで，中心角膜厚と緑内障罹病率との関連は研究によってさまざまであり，また，中心角膜厚が緑内障進行の危険因子かどうかは明らかではないとしている一方，中心角膜厚が厚いことは高眼圧症から緑内障を発症する危険因子であると報告している。

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