ラタノプロストによる眼圧下降と眼圧変動の抑制

Suppression of diurnal variation of intraocular pressure by topical latanoprost

　ラタノプロスト点眼による眼圧日内変動の変化を，原発開放隅角緑内障3例6眼について検索した。6眼とも手術の既往がなく，それまで使用中の眼圧下降薬全部または一部をラタノプロストの夜間1回点眼に切り替え，変更前とそれぞれ3,5,15か月後の眼圧と日内変動幅を測定した。ラタノプロスト使用前15.9±1.2mmHgの眼圧は変更後13.5±1.5mmHgになり，有意に下降した（p＜0.01）。下降幅は4.0〜0.4mmHg，平均2.4mmHgであった。日内変動幅は，1日に11回測定した最高眼圧と最低眼圧の差と定義した。日内変動幅は，変更前6〜13mmHg，平均8.7mmHgであり，変更後2〜5mmHg，平均4.0mmHgになり、有意に減少した（p＜0.005）。変更前後の眼圧変動幅の差は，最大8mmHg、最小2mmHg，平均4.7mmHgであった。ラタノプロスト点眼は，他の眼圧下降薬の点眼に比較して，平均眼圧を下降させ、眼圧日内変動を抑制した。

We evaluated the change of diurnal variation of intraocular pressure (IOP) induced by latanoprost in 6 eyes of 3 patients of primary open-angle glaucoma. All the eyes had no history of glaucoma surgery. Each eye received latanoprost instillation once a day after discontinuing other hypotensive medications. The IOP averaged 15.9 ± 1.2 mmHg before latanoprost and significantly decreased to 13.5± 1.5mmHg 3, 5 and 15 months after switching to latano-prost (p＜0.01). The amount of IOP decrease ranged from 4.0 to 0.4mmHg, average 2.4mmHg. The diurnal variation was defined as the difference between maximum and minimum IOP among 11 measurements during a 24-hour period. It ranged from 6 to 13mmHg, average 8.7mmHg before latanoprost. It significantly decreased to 2 to 5mmHg, aver-age 4.0mmHg, after switching to latanoprost (p＜0.005). The difference in diurnal variation before and after latano-prost ranged from 2 to 8mmHg, average 4.7mmHg. The findings show that topical latanoprost is more effective in re-ducing IOP and in suppressing diurnal variation than other medications.