Displaced Nuclear Fragments Into the Vitreous Complicating Phacoemulsification Surgery in the United Kingdom: Epidemiology and Risk Factors

Abstract

Abstract: : Purpose: To study the epidemiology and risk factors contributing to displacement of nuclear fragments into the vitreous (DNFV) complicating phacoemulsification surgery in the United Kingdom Methods: Cases were collected prospectively between March 2003– March 2004 by active surveillance through the British Ophthalmological Surveillance Unit (BOSU). All independently practicing surgeons in the united kingdom received a monthly reporting card from BOSU and data on reports was collected using a standard incident questionnaire. Case control analysis of risk factors was performed by visiting 10 randomly selected centres using a total of 520 cases of uncomplicated phacoemulsification. Validation analysis to assess under–reporting was performed in a total of 14 randomly selected units. Results: 607 reports were made to BOSU during the reporting period. The estimated incidence of DNFV was 0.24–0.30%. Male: Female ratio was 42.6%:57.4%. Complications group was significantly older than control group mean 77.7 versus 72.8 (t=4.68 p<0.001). Significant risk factors were posterior synechiae, incomplete pupil dilation (60.6% versus 12.4%), pseudoexfoliation (5.8% versus 1.3%), previous vitrectomy (8.1% versus 1.9%), use of vision blue (13.7% versus 2.4%) and subtenon’s anaesthesia (49.6% versus 41.1%) Conclusions: The incidence of DNFV during phacoemulsification surgery in the UK is two to three per 1000 operations. Risk factors have been identified which should help guide case selection for phacoemulsification surgery and modify techniques.

Keywords: cataract • vitreoretinal surgery