Role of vitrectomy with optic capture

Abstract

The authors of the article on the role of vitrectomy with optic capture1 have conducted a pioneering work and suggest that anterior vitrectomy is necessary with optic capture in children between 5 and 12 years of age with congenital cataracts. The authors used a single-piece poly(methyl methacrylate) (PMMA) intraocular lens (IOL) with a 5.25 mm optic in the study. Posterior capsule opacification (PCO) is affected by many factors such as patient age, surgical technique, use of heparin,2 underlying ocular disease, IOL material,3 IOL design,4 and IOL diameter.5 It has been well documented that a square-edge design, acrylic IOL material, and large optic inhibit PCO. The AcrySof® IOL (Alcon) has been shown to have the lowest PCO rates, which has been attributed to its square-edge design and an increased adhesiveness to the posterior capsule. It has also been suggested that a large optic produces a more peripheral barrier to epithelial cell migration and a larger overall diameter with increased haptic angulation produces greater backward pressure on the posterior capsule, which is maximum at the edge of the optic. All these factors inhibit migration of lens epithelial cells under the IOL optic and thus prevent PCO. I would like to suggest that making a primary opening in the posterior capsule and doing an anterior vitrectomy may not be required in children older than 5 years when an AcrySof IOL is used. In my experience, the incidence of PCO in pediatric cataract surgery has decreased considerably with in-the-bag implantation of an AcrySof IOL with PMMA haptics (and, recently, the single-piece AcrySof IOL) and one might not be justified in opening the posterior capsule and performing an anterior vitrectomy, a procedure that increases the risk of cystoid macular edema and subsequent retinal detachment. The procedure of posterior capsulorhexis with optic capture is also technically demanding, with a long learning curve, and is prone to complications until a high level of surgical expertise is achieved. It may be a difficult procedure for many ophthalmic surgeons. Another point of concern is that use of small-optic (5.25 mm) IOLs in children (who have a comparatively larger pupillary diameter) may cause problems of glare and diplopia, especially in dim illumination, and thus be an amblyogenic factor. Primary posterior capsulorhexis with optic capture and anterior vitrectomy in children older than 5 years is still a controversial issue. Further long-term studies are required to establish the role of anterior vitrectomy and prove the effect of IOL size, material, and design on reducing PCO after pediatric cataract surgery. Tanuj Dada MD aNew Delhi, India