筋膜囊下浸润麻醉对视网膜脱离患者术中视觉影响的研究

Visual impact of sub-tenon＆#39;s anesthesia during surgery for retinal detachment

目的 研究筋膜囊下浸润麻醉对视网膜脱离患者在玻璃体切除术或超声乳化白内障吸除联合玻璃体切除术过程中的视觉影响及其影响因素.方法 前瞻性病例系列研究.2012年10月至2013年12月于汕头国际眼科中心就诊的视网膜脱离患者104例（104只眼）,于筋膜囊下浸润麻醉后行玻璃体手术或前后段联合手术.在麻醉后的5 min、超声乳化白内障吸除后、核心部玻璃体切除后、周边玻璃体切除后和手术结束时,排除对侧眼的影响和显微镜的光漂白作用,实时调查患者能否看到显微镜的亮光.并在术前1天、术后1.5个月和3个月分别检查术眼最佳矫正视力和视觉诱发电位（VEP）并进行对比.不同手术方式,是否去光漂白效应的黑矇检出率比较采用卡方检验;黑矇与无发生黑矇患者的年龄、术眼术前视力比较采用独立样本t检验.手术前后视力比较采用单因素方差分析;VEP振幅比较采用配对t检验.结果 未排除对侧眼影响时,在各个检查点黑矇发生率均为0.严密遮盖排除对侧眼影响后,麻醉后5 min、白内障摘除术后、核心部玻璃体切除术后、周边部玻璃体切除术后及术毕时,术眼黑矇检出率分别为72.1%（75/104）、93.8%（75/80）、96.2%（100/104）、96.2%（100/104）及86.5%（90/104）.排除光漂白影响后,各相应检查点黑矇检出率分别为51.9%（54/104）、85.0%（68/80）、85.6%（89/104）、84.6%（88/104）及66.3%（69/104）.严密遮盖对侧眼及排除光漂白作用后,至少在术中某个阶段出现黑矇的发生率为95.2%（99/104）.去漂白后真正黑矇的99例患者中,54.5%（54/99）患者黑矇发生在筋膜囊下浸润麻醉后的5 min内.30.3%（30/99）术中黑矇的患者在手术结束时恢复光感,所有患者在术后第1天均恢复光感以上视力.术前、术后1.5和3个月患者平均最佳矫正视力分别为1.75±0.78、0.96±0.63、0.92±0.57,差异有统计学意义（F=50.61,P〈0.01）.术前图形VEP未能引出波形者,分别有43.6%（24/55）和61.4%（35/57）的患者于术后1.5和3个月复查时重新引出波形;术前顺利引出波形者,术后图形VEP振幅较术前显著提高（t1.5个月=-2.69,t3个月=-2.97;P〈0.05）.结论 大部分患者于筋膜囊下浸润麻醉后行玻璃体切除术或前后段联合手术的不同阶段可出现黑矇.推测麻醉剂对视觉冲动传导的阻断作用是导致术眼黑矇的主要原因,光漂白作用也有一定影响.黑矇为一过性,对视功能的恢复无明显影响.

Objective To investigate the visual impact and influence factors of sub-Tenon＆#39;s anesthesia in retinal detachment patients during pars plana vitrectomy （PPV） or combined phacoemulsification and PPV surgery. Methods In this prospective case series study, 104 consecutive patients who underwent PPV or combined phacoemulsification and PPV under sub-Tenon＆#39;s anesthesia between October 2012 and December 2013 were enrolled. Intraoperatively, the patients were asked whether they could see the light of the operating microscope or not at 5 minutes after sub-Tenon＆#39;s anesthesia, and at the end of phacoemulsification, core vitreous removal, peripheral vitreous removal and the whole surgery,with their contralateral eyes being covered tightly and no photobleaching. The best corrected visual acuity and visual evoked potentials were examined and compared with each other preoperatively and at 1.5 months and 3 months postoperatively. Chi-square test was used to compare the detection rate of amaurosis between different modus operandi and whether covered contra-lateral eye. Student-t test was used to compare the difference of age and preoperative BCVA between the patients with or without experienced amaurois. Lastly, BCVA between different times were tested by one-way ANOVA analysis. Results Without covering the contralateral eyes, the incidence of no light perception in various surgical steps was 0%, while it was 72.1%（75/104）, 93.8%（75/80）, 96.2%（100/104）, 96.2%（100/104） and 86.5%（90/104） at the five timepoints, respectively, when the contralateral eyes were covered tightly. The incidence was 51.9%（54/104）, 85.0%（68/80）, 85. 6%（89/104）, 84.6%（69/104） and 66.3%（88/104）, respectively, after photobleaching was excluded. Approximately 95.2%（99/104） of patients reported no light perception at least once, 54.5%（54/99） reported no light perception 5 minutes after sub-Tenon＆#39;s anesthesia, and 30.3%（30/99） recovered light perception when the surgery was finished. All eyes recovered to at least light perception on the first postoperative day. The best corrected visual acuity and visual evoked potentials at 1.5 months and 3 months postoperatively were significantly better than those before surgery. The BCVA was 1.75 ± 0.78 preoperative, 0.96 ± 0.631.5 months after operation, and 0.92 ± 0.573 months after operation. There was a significant statistical difference between preoperative BCVA and postoperative BCVA （F=50.61, P〈0.01）. In patients without waveform detection preoperatively, PVEP waveform could be found in 43.6%and 61.4%of the pactients at 1.5 months and 3 months after operation respectively. In those had certain waveform preoperatively, PVEP amplitudes rise significantly after surgery（t1.5=-2.69, t3=-2.97, P〈0.05）. Conclusions No light perception was detected in various surgical steps of vitrectomy under sub-Tenon＆#39;s anesthesia in most patients. The blocking of optic nerve conduction may be caused by sub-Tenon＆#39; s anesthesia. Photobleaching can also have some effect. The incidence of no light perception during the surgery was not correlated with preoperative visual acuity, age and gender. Moreover, the effect was transient and harmless to visual function.