Retained lens fragments: Nucleus fragments are associated with worse prognosis than cortex or epinucleus fragments

Purpose. To identify factors that determined the outcome of eyes that underwent pars plana vitrectomy for retained lens fragments after phacoemulsification. Methods. A retrospective review of the records of 63 eyes that underwent vitrectomy for retained lens fragments after phacoemulsification. Fragments were defined as nuclear if they contained any nucleus component or non-nuclear if they contained only cortex and epinucleus. Nuclear fragments were further divided into large (at least 1/3 the size of the nucleus) or small. Results. A total of 67% of eyes had retained nuclear fragments and 33% had non-nuclear fragments. Of the eyes with nuclear fragments, 64% had large fragments and 36% had small fragments. Statistical analysis revealed that the lens fragment type was the major determinant of the final visual acuity (VA). Only 38.8% (14/36) of the eyes with nuclear fragments achieved final VA of 20/40 or better, compared with 77.7% (14/18) of eyes with non-nuclear fragments (p=0.007). All other parameters, including size of the nuclear fragment, were not correlated with final VA. The major complications encountered in this series were retinal detachment (12.6%), pseudophakic bullous keratopathy (6.3%), cystoid macular edema (15.8%), and glaucoma (15.8%). Conclusions. The major finding of our study is that posterior dislocation of nuclear lens fragments is associated with worse visual outcome than that of non-nuclear fragments. This may be related to a more complicated course of the cataract surgery, direct mechanical damage to the retina, a stronger inflammatory response, or a more traumatic vitrectomy procedure.