577、532nm激光全视网膜激光光凝治疗非增生型糖尿病视网膜病变疗效比较

Effect of wavelength in the efficacy for treatment of non-proliferative diabetic retinopathy

目的对比观察577、532nm波长激光全视网膜激光光凝（PRP）治疗重度非增生型糖尿病视网膜病变（NPDR）的疗效。方法前瞻性临床对照研究。临床确诊的重度NPDR患者23例41只眼纳入研究。根据接受治疗的激光波长，随机数字表法将患眼分为577nm组和532nm组，分别为11例20只眼和12例21只眼。分别使用577、532nm激光单点模式行PRP。记录两组激光功率、光斑点数、能量密度。治疗后1d，1、3、6、12个月行最佳矫正视力（BCVA）、散瞳后间接检眼镜、视野、全视野闪光视网膜电图（F-ERG）、光相干断层扫描（OCT）检查。观察治疗后BCVA、30°～60°环形范围内视野平均阈值敏感度，F-ERGa、b波振幅、平均黄斑中心凹厚度（CMT）；治疗后6个月行荧光素眼底血管造影（FFA）检查，观察患眼新生血管及无灌注区变化情况。以BCVA提高或不变为治疗有效。结果两组患眼治疗有效率分别为85．0％、23．8％；治疗有效率比较，差异有统计学意义（X2=15．43，P〈0．05）。两组患眼视野平均阈值敏感度及F-ERGa、b波振幅治疗后1d均较治疗前1d降低，差异均有统计学意义（F=8．68、7．57、4．52，P〈0．05）；3、6、12个月，视野平均阈值敏感度（t=2．41、3．48、1．23）及F-ERGa、b波振幅（a波：t=5．82、4．45、7．83；b波：t=5．40、3．23、4．67）提高值比较，差异均有统计学意义（P〈0．05）。治疗后6个月，两组患眼均未出现新生血管及无灌注区。577nm组、532nm组平均激光功率分别为（436．25±54．65）、（446．43士35．61）mw；平均激光光斑点数分别为（1952．95±299．09）、（2119．05±302．69）点；平均能量密度分别为（7．60±1．30）、（7．60±3．00）mW×ms／μm2。两组激光功率（t=1．35）、光斑点数（t=2．85）、能量密度（t=1．99）比较，差异均无统计学意义（P〉0．05）。结论与532nm波长激光比较，577nm波长激光治疗有效率高，视功能损伤程度较小。

Objective To compare the therapeutic effects of 577 nm laser and 532 nm laser panretinal photocoagulation （PRP） in the treatment of non-proliferative diabetic retinopathy （NPDR）. Methods This is a prospective controlled study. A total of 23 patients （41 eyes） with clinically diagnosed severe NPDR were randomly divided into two groups including 577 nm group （11 patients, 20 eyes） and the 532 nm group （12 patients, 21 eyes）. 577 nm group and 532 nm group received 3 - 4 times PRP with single-point mode. The laser energy and the number of laser spots were compared, and the laser energy density was calculated. Before treatment and 1 day, 1, 3, 6 and 12 months after treatment, the changes of best corrected visual acuity （BCVA）, average threshold sensitivity, a/b-wave amplitude of flash ERG （F-ERG） in the 30° - 60° visual field, and fundus fluorescein angiography （FFA） were compared between two groups. Results The response rate was 85.0% and 23.8%, respectively in the 577 nm and 532 nm group, the difference was statistically significant （Zz ： 15.43, P（0. 05）. Compare to the pre-treatment measurement, the average threshold sensitivity, a/b wave amplitude of F-ERG and the 30° - 60°visual field were reduced at 1 day after treatment both in the 577 nm and 532 nm group, the difference were statistically significant （F=8.68, 7.57, 4.52; P〈0.05）. The average threshold sensitivity （t= 2.41, 3.48, 1.23）, a/b wave amplitude （a wave： t=5.82, 4.45, 7.83;b wave;t=5.40, 3.23, 4.67） of F-ERG were different between 577 nm and 532 nm group at 3 , 6 and 12 months after treatment （P〈0.05）. There was no retinal neovascularization and non-periusion region in two groups at 6 months after treatment. The average laser power were （436.25 ±54.65） and （446.43 ± 35.61） mW, number of laser spots were （1952.95 ± 299.09） and （2119.05 ±302.69） spots, energy density were （7.60±1.30） and （7.60±3.00） mWX× ms/m2 in the 577 nm group and 532 nm group, respectively. There was no difference in average laser power （t= 1.35）, number of laser spots （t=2.85） and energy density （t=l. 99） between two groups （P〉0.05）. Conclusion Compared with the 532 nm laser, 577 nm laser treatment has better visual outcomes for NPDR patients.