25-G微创玻璃体视网膜手术后眼屈光稳定性

Surgically induced refractive changes in 25-gauge transconjunctival sutureless vitrectomy

目的对比分析25-gauge（G）微创玻璃体视网膜手术与20-G手术术后眼屈光稳定性。方法前瞻性随机病例对照研究。选取121例（121眼）需行玻璃体视网膜手术的眼底病患者．根据随机数字表随机分为A、B两组。A组6l眼采用常规20-G玻璃体切割手术，B组60眼采用25-G微创玻璃体切割手术，对比观察术前与术后1周、4周和12周视力、屈光度、角膜地形图改变。数据采用卡方检验、独立样本t检验、单因素方差分析、Mann．Whitney非参数检验进行分析。结果术后1周和4周．B组视力优于A组（X^2=8．81、6．65，P均〈0．05）。A组术后屈光度向远视漂移，在术后12周回归至接近术前水平。B组术后屈光度向近视漂移。A组术后1周、4周、12周较术前改变的平均球镜度为（±1．93±0．07）D、（＋1．06±0．04）D、（＋0．15±0．03）D，较术前改变的平均散光度为（1．62±0．07）D、（1．0S±0．05）D、（0．41±0．03）D。B组术后1周、4周、12周较术前改变的平均球镜度为（-0．06±O．02）D、（-0．04±0．03）D、（-0．03±0．02）D，较术前改变的平均散光度为（0．05±0．01）D、（0．03±0．01）D、（0．03±0．02）D。术后l周、4周、12周球镜度改变在两组中差异存在统计学意义（拇200．6、159．3、26．0，P均〈0．01）。术后各时间段散光度改变在两组中差异存在统计学意义（t=173．4、156．3、82．3，P均〈0．01）。A组角膜散光屈光率（SimKl-K2）、表面不对称指数（SAI）、表面规则指数（sin）在各个时问点的差异有统计学意义（F=4．21、3．44、3．28，P〈0．05），而B组患者各角膜地形参数在术前、术后各时间段差异无统计学意义。A、B两组之间在术后短期内角膜SimKl．K2、SAI、SRI的改变量差异有统计学意义（U=51．5、45．5、47．0。P〈0．05）。结论与20．G常规玻璃体切割手术相比，25一G微创玻璃体视网膜手术后眼屈光稳定性更好，可获得更完善的视功能。

Objective To compare the changes in refractive status after 25-gauge sutureless vitrectomy and 20-gauge standard vitreetomy. Methods One hundred and twenty-one eyes of 121 patients who presented with vitreoretinal disease were included in this prospective study. Patients were randomly divided into two groups, the A group, 61 eyes that underwent 20-gauge standard vitrectomy, and the B group, 60 eyes that underwent 25-gauge vitrectomy. Outcome measures included visual acuity, refractive power, and changes in corneal topography after surgery. Data were analyzed with chi-square test, independent samples t test, one-way ANOVA and Mann-Whitney test. Results The visual acuity of the B group was much better than that of the A group at one week and one month after surgery （X^2=8.81, P=0.012; X^2=6.65, P=0.036）. The postoperative refractive error in the A group developed into hyperopia, then gradually returned to baseline at three months after surgery. The spherieal and astigmatism powers for eaeh timepoint were significantly different in the A group （F=530.12, P〈0.05, F=392.06, P〈0.05）, but no significant difference was found in the B group. In the A group, changes of spherical power at 1 week, 4 weeks, 12 weeks after surgery were （＋1.93_＋0.07）D, （＋1.06±0.04）D, （＋0.15±0.03）D, and changes of astigmatism power were（1.62±0.07）D, （1.05±0.05）D, （0.41±0.03）D. In the B group, changes of spherical power at 1 week, 4 weeks, 12 weeks after surgery were （-0.06±0.02）D, （-0.04±0.03）D, （-0.03±0.02）D, and changes of astigmatism power were （0.05±0.01）D, （0.03±0.01）D, （0.03±0.02）D. Change of spherical power between the A and B groups at 1 week, 4 weeks, 12 weeks after surgery was significant different （t=200.6, 159.3, 26.0, P〈0.01 for all）, as well as astigmatism power （t=173.4, 156.3, 82.3, P〈0.01 for all）. At one week after surgery, corneal topography analysis showed that corneal SimK1-K2, surface asymmetry index （SAI）, and surface regularity index （SRI） were significantly different compared to baseline （F=4.21, 3.44, 3.28, P〈0.05 for all）. However, the changes in corneal topography before and after surgery in the B group were still statistically insignificant. The changes of SimK1-K2, SAI, SR1 in A group were significantly more than that in B group （U=51.5, 45.5, 47.0, P〈0.05 for all）. Conclusion Compare to a 20-gauge vitreetomy system, a 25-gauge transeonjunctival sutureless vitreetomy system provides a more stable refractive status and better improvement in visual function postoperatively in vitreoretinal surgeries.