Determinants of visual outcome after pars plana vitrectomy for posteriorly dislocated lens fragments in phacoemulsification

Purpose: To evaluate the visual outcome of patients with posteriorly dislocated lens fragments after phacoemulsification managed with pars plana vitrectomy (PPV) and identify risk factors for poor visual outcome. Setting: Vitreo-Retinal Service, St. Paul Eye Unit, Liverpool, United Kingdom. Methods: The medical records of all patients who had PPV for posteriorly dislocated lens fragments after phacoemulsification between March 1993 and August 1998 were retrospectively reviewed. Demographics, preexisting eye conditions, details of the previous cataract surgery, findings at presentation, details of the vitreoretinal procedure, final visual acuity, and complications observed during the follow-up were evaluated. Univariate and multiple regression analyses were used to determine the significance of these clinical variables as determinants of poor visual outcome (visual acuity 6/12 or worse). Results: Of the 106 patients identified, 89 had a full set of data and were included in the study. In 79 patients (89%), PPV was performed from 1 to 357 days (median 15 days) after cataract extraction. In 10 patients (11%), PPV was done on the same day as the cataract surgery. Sixty-two patients (69%) had a final visual acuity of 6/12 or better. Preexisting eye disease (P < .01), PPV delayed for more than 4 weeks (P < .03), occurrence of retinal detachment after vitrectomy (P < .01), and the use of ultrasound (US) fragmentation (P < .01) were statistically significantly correlated with a poor visual outcome. Conclusions: Posterior dislocated lens fragments after phacoemulsification were safely retrieved using PPV. It appears that intervening early (within 4 weeks) and avoiding the use of US fragmentation are associated with a better visual outcome and reduced rate of postoperative complications.