Fahd Daoud C, Jabbour Elyse, Fahed Charbel D
Arq Bras Oftalmol. 2014 May-Jun;77(3):159-63. doi: 10.5935/0004-2749.20140041.
To assess the reliability and reproducibility of static cyclotorsion correction (SCC) measurements made using the Schwind Amaris Excimer laser in patients undergoing LASIK or PRK, and compare the outcomes of treating astigmatism with and without SCC.
Eighty eyes of 40 patients were included in this study. All eyes underwent 2 or 3 sets of five measurements: before and after speculum placement, and after flap-lift (in LASIK cases). We assessed the reproducibility, accuracy, and the percentage of “no catch” measurements. The astigmatism was calculated pre-and 3-months-postoperatively by vector analysis.
The mean age of the patients was 23.67 ・} 4.19 years. Preoperative spherical equivalent and astigmatism were -2.56 ・} 2.86 D and +1.36 ・} 0.98 D, respectively. The mean measurement time was 15.1 seconds per measurement. The percentages of “no catch” were: 63.8%, 14.9%, and 26.9%; pre-speculum, post-speculum, and post flap-lift, respectively. Cyclotorsion of ≥}2° was seen in 41.25% and 66% of the cases before and after the flap-lift, respectively. Significant cyclotorsion (≥}5°) was seen in 12.50% and 18% of the eyes pre and post flap-lift. The mean astigmatism dropped from +1.53 D@1° to +0.34D@3° when SCC was used and from +1.86D@1° to +0.23D@7° when SCC was not used. No statistical difference was noticed between the groups (p>0.05) in the postoperative residual astigmatism. A postoperative astigmatism of ≥ D was seen in 10% and 20% of eyes with and without SCC, respectively (p<0.01).
Although not always feasible, the SCC measurement is a simple and useful tool. Postoperative astigmatism showed less variability when SCC was used.
评估在接受准分子原位角膜磨镶术（LASIK）或准分子激光角膜表面切削术（PRK）的患者中，使用Schwind Amaris准分子激光进行静态旋转性散光矫正（SCC）测量的可靠性和可重复性，并比较进行和不进行SCC治疗散光的效果。
本研究纳入40例患者的80只眼。所有眼睛均进行2或3组，每组5次测量：放置开睑器前后，以及掀瓣后（LASIK病例）。我们评估了可重复性、准确性以及“未捕获”测量的百分比。术前和术后3个月通过矢量分析计算散光度数。
患者的平均年龄为23.67 ± 4.19岁。术前等效球镜度和散光分别为-2.56 ± 2.86 D和+1.36 ± 0.98 D。每次测量的平均时间为15.1秒。“未捕获”的百分比分别为：放置开睑器前63.8%、放置开睑器后14.9%、掀瓣后26.9%。分别在掀瓣前和掀瓣后41.25%和66%的病例中观察到≥2°的旋转性散光。在掀瓣前和掀瓣后分别有12.50%和18%的眼睛出现显著旋转性散光（≥5°）。使用SCC时，平均散光度数从+1.53 D@1°降至+0.34D@3°，未使用SCC时从+1.86D@1°降至+0.23D@7°。两组术后残余散光无统计学差异（p>0.05）。分别在10%和20%使用和未使用SCC的眼睛中观察到术后散光≥ D（p<0.01）。
尽管并非总是可行，但SCC测量是一种简单且有用的工具。使用SCC时，术后散光的变异性较小。
