London Vision Clinic, London, UK.
J Refract Surg. 2010 Feb;26(2):107-19. doi: 10.3928/1081597X-20100121-06. Epub 2010 Feb 12.
To quantify the accuracy and reproducibility of central flap thickness for flaps created with the VisuMax femtosecond laser system.
This was a prospective study of 24 eyes of 12 myopic LASIK patients. The VisuMax femtosecond laser was used to create flaps with an intended central flap thickness of 110 microm. Artemis 1 very high-frequency digital ultrasound scans were performed preoperatively and 3 months postoperatively. Central flap thickness was calculated as the addition of the preoperative epithelial thickness and the postoperative stromal component of the flap. Descriptive statistics (mean, standard deviation, minimum, maximum, and range) of central Reinstein Flap Thickness were calculated for all flaps. Central flap thickness accuracy was calculated as the difference between the mean and intended flap thickness. Reproducibility was evaluated as the flap thickness standard deviation between eyes.
At 3 months, mean central Reinstein Flap Thickness was 112.3+/-7.9 microm (range: 102.6 to 132.9 microm). The accuracy was +2.3 microm and reproducibility was 7.9 microm. On average, the flap diameter was 0.47+/-0.21 mm greater than the intended flap diameter.
The VisuMax femtosecond laser system was found to create flaps accurate to the intended thickness in the center with a low standard deviation, which will help reduce the risk of obtaining an excessively thick flap.
定量评估 VisuMax 飞秒激光系统制作的角膜瓣中央厚度的准确性和可重复性。
这是一项前瞻性研究,共纳入 12 例(24 只眼)接受近视 LASIK 手术的患者。采用 VisuMax 飞秒激光制作中央厚度预期为 110μm 的角膜瓣。术前及术后 3 个月采用 Artemis 1 超高频数字超声扫描系统进行检查。中央角膜瓣厚度定义为术前上皮层厚度与术后角膜瓣基质层厚度之和。对所有角膜瓣的中央 Reinstein 瓣厚度(单位:微米)进行描述性统计分析(平均值、标准差、最小值、最大值和范围)。中央角膜瓣厚度的准确性定义为平均厚度与预期厚度的差值。可重复性定义为双眼之间角膜瓣厚度的标准差。
术后 3 个月,平均中央 Reinstein 瓣厚度为 112.3±7.9μm(范围:102.6μm 至 132.9μm)。准确性为+2.3μm,可重复性为 7.9μm。平均而言,角膜瓣直径比预期直径大 0.47±0.21mm。
VisuMax 飞秒激光系统制作的角膜瓣中央厚度准确,且标准差较低,这有助于降低获得过厚角膜瓣的风险。