Influence of the "Inverted U Method" Nd: YAG Laser Posterior Capsulotomy on Anterior Segment Parameters, Decentration and Tilt of Intraocular Lens in Patients after Phaco-vitrectomy.

PURPOSE

To investigate the effects of the "inverted U method" Nd:YAG laser posterior capsulotomy on anterior segment parameters, decentration and tilt of intraocular lens (IOLs) and visual acuity in posterior capsular opacification (PCO) patients after combined phaco-vitrectomy.

METHODS

Seventy-six patients (76 eyes) were enrolled in this study, who were diagnosed as PCO and underwent "inverted U method" Nd:YAG laser posterior capsulotomy. All patients had undergone previous combined phaco-vitrectomy for rhegmatogenous retinal detachment. The parameters including IOL decentration, angle of IOL tilt, anterior chamber angle (ACA), anterior chamber depth (ACD), anterior chamber volume (ACV), central corneal thickness (CCT), keratometry, pupil size, axial length (AL), intraocular pressure (IOP), refractive status, corrected distance visual acuity (CDVA), objective scattering index (OSI) and Chinese version of Visual Function 14 (VF-14) index were obtained before and 3 months after capsulotomy.

RESULTS

After capsulotomy, the tilt angle and decentration of the IOLs at both vertical (tilt: = .004, decentration: = .029) and horizontal meridian (tilt: = .001, decentration: = .017) were significantly decreased, ACA increased ( = .015), CDVA (.000), VF-14 score (.000) and OSI ( = .000) were significantly improved. There were a significant decrease in cylindrical error ( = .001) and a myopic shift in spherical error ( = .001) after the capsulotomy. No significant differences in ACD, ACV, CCT, keratometry, pupil size, AL and IOP were detected ( > .05 for all).

CONCLUSION

The "inverted U method" Nd: YAG laser posterior capsulotomy decreases tilt and decentration of the IOL, increases ACA and causes no change in ACD, ACV, CCT and IOP in patients after phaco-vitrectomy. These changes make a decrease in cylindrical error and a myopic shift in spherical error. Laser capsulotomy significantly improves visual acuity.