An Improved Nd:YAG Laser Posterior Capsulotomy Technique for the Treatment of Posterior Capsule Opacification

Objective: To compare the efficacy of the improved Nd:YAG laser posterior capsulotomy technique (the tension line method) with the traditional cruciate Nd:YAG laser posterior capsulotomy technique. Methods: In this prospective, controlled study, 57 simple cataract patients (60 eyes) who had undergone intraocular lens implantation participated from December 2014 to December 2015 at the Eye Hospital, Wenzhou Medical Universtiy. They were enrolled after developing posterior capsular opacification (PCO) that needed Nd:YAG laser posterior capsulotomy. Patients were randomly divided into two groups of 30 eyes each based on different Nd:YAG laser capsulotomy techniques (the tension line group and the cruciate group) for treatment. Patients were reviewed on the first day, and at one week and one month after the capsulotomy was completed. Laser single minimum cut energy, points, total energy, operation time and uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), spherical diopters, cylindrical diopters, spherical equivalents (SE), and intraocular pressure (IOP) were recorded as well as reports of floater symptoms. Data were analyzed using independent sample t test, Chi-square test, and repeated measurements ANOVA. Results: There were obvious improvements in UCVA (F=82.23, 67.60, P 0.05). The laser single minimum cut energy, points, total energy, and operation time of the tension line group were significantly lower than the cruciate group (t=3.55, 5.79, 6.19, 8.26, P<0.01). IOP in the tension line group was lower than that before surgery (F=3.48, P=0.031), there was no statistically significant difference between the two groups. There was no obvious difference between the groups in the number of eyes with floater symptoms. There was a significant decrease in postoperative cylindrical diopters in both groups (F=9.54, 4.78, P<0.05), there was no statistically significant difference between the two groups. There was no significant change in postoperative spherical diopters and SE in both groups, and also there was no significant difference between the two groups. Conclusions: The improved Nd:YAG laser posterior capsulotomy technique (the tension line method) for the treatment of intraocular lens posterior capsular opacification is safe and effective. Compared with the traditional cruciate technique, the improved technique uses less laser energy, has a shorter operation time. Key words: lasers, solid-state; posterior capsule opacification; laser posterior capsulotomy