超音波白内障手術における点眼麻酔とテノン嚢下麻酔の比較検討

Comparison of anesthesia by instillation and sub-Tenon's capsulary injection for cataract surgery with phacoemulsification and aspiration

　超音波白内障手術において，点眼麻酔のみの群（点眼群）と点眼麻酔とテノン嚢下麻酔を併用した群（テノン嚢下群）につき，疼痛の発生頻度を比較検討した。手術侵襲が虹彩毛様体に及ぶ，内眼操作を多く含む過程では，疼痛の訴えの頻度は，点眼群219眼中14眼（6.4％），テノン嚢下群210眼中12眼（5.7％）と，有意差は認められなかった。しかし，その直後の外眼操作を多く含む過程では，点眼群219眼中17眼（7.7％），テノン嚢下群210眼中7眼（3.3％）と，点眼群のほうが有意に疼痛の訴えが多かった。以上のことから，虹彩毛様体組織は，外眼部の有する体性痛とは異なる痛覚受容を持つことが示唆された。

We compared the efficacy of two methods of anesthesia for cataract sugery in 429 eyes. Cataract surgery with phacoemulsification and aspiration was performed after topical instillation of 4% lidocaine in 219 eyes and after injection of 1 ml of 2% lidocaine under the Tenon's capsule in 210 eyes. During intraocular manipulations, pain was noted in 14 eyes, 6.4%, in the instillation group and in 12 eyes, 5.7%, in the injection group. The difference was not significant. During extraocular manipulations, pain was noted in 17 eyes, 7.7%, in the instillation group and in 7 eyes, 3.3%, in the injection group. The difference was significant. The findings suggest that the pain perception by the iridociliary tissue is different from the somatic one by the cornea and the conjunctiva.