経強膜毛様体光凝固術後の問題点と眼圧変動

Clinical study of transscleral YAG laser cyclodiathermy

　薬物治療や濾過手術の無効な難治性緑内障患者18眼を選び，経強膜毛様体光凝固術を施行した。眼圧の変化は術後1日後より起こり，1週後には18.3±2.7mmHgと低下したが，1か月後には23.3±8.3mmHgに上昇した。この経過中，4回の処置を必要とした症例もあった。

　経強膜毛様体光凝固術の照射方法についての家兎を用いて照射部位や出力などの照射条件を検討した。実験結果より，高エネルギーほど，眼圧下降期間が長いこと，また同じ部位を繰り返し照射するより，場所を替え，照射領域を替えたほうが効果があった。

Transscleral YAG laser cyclodiathermy (TSYLC) is considered useful to glaucoma not amenable to other forms of treatment. We also did the animal study using pigmented rabbit, to clarify which part of the eye should be irradiated.

The average preoperative pressure was 34.5mmHg with a range of 24 to 49mmHg. Among these eyes, two required three treatments, and one required four treatments. The success rate (≦20mmHg) was 71% after one year. The study in pigmented rabbits suggests that it is better to irra-diate the other part of the sclera rather than to repeat the application on the same part.

Although this modality of transscleral cyclodiathermy is simple and is performed on an outpatient basis, we experienced a case of complete loss of vision. If such cases occur in more frequency, this application shoud be restricted to severe end stage glaucoma.