超音波乳化吸引術における超音波連続発振モードとインクリメンタルパルスモードとの前向き検討による比較

Prospective clinical comparison between continuous and incremental pulse mode during phacoemulsification

要約　目的：超音波水晶体乳化吸引術での連続発振モードとインクリメンタルパルスモードとの比較。対象：超音波水晶体乳化吸引術を行った134眼を対象とした。内訳は連続発振49眼，ハイパルス45眼，ローパルス40眼で，超音波発振以外の手術条件は統一した。結果：超音波発振時間は連続発振群で有意に長く，超音波エネルギーは連続発振群よりもパルス群で短く，ローパルス群とは有意差があった。平均超音波出力，手術時間，角膜内皮細胞減少率については，3群間に有意差がなかった。結論：パルスモードを使うことで超音波発振時間を短縮できるが，破砕と吸引効率が悪くなり，超音波発振時間が延長する。通常の硬さの核では連続発振モードよりもパルスモードを用いたほうが眼球への侵襲が小さいと思われる。

Abstract.　Purpose：To compare continuous and incremental pulse mode during phacoemulsification-aspiration. Cases：This prospective study was made on 134 eyes that received cataract surgery. The series comprised 49 eyes operated with continuous mode ultrasound,45 eyes with high pulse mode,and 40 eyes with low pulse mode. All the eyes were operated under the same condition excepting mode of ultrasound. Results：Duration of ultrasound application was significantly longer in eyes receiving continuous ultrasound. Total ultrasound energy was significantly less in low-pulse mode group than in continuous one. There was no difference among 3 groups regarding average ultrasound output,duration of surgery,or corneal endothelial loss. Conclusion：Ultrasound activation time is shortened by using pulse mode. This effect is offset by diminished effect during phacoemulsification and aspiration. We advocate pulse mode during surgery for cataract with nucleus of average hardness.