Abstract
Abstract: :
Purpose: Implantation of intraocular lenses (IOL’s) has been shown to be associated with a foreign body reaction as evidenced by the formation of giant cells on the lens surface. It is also known that diabetics are at a greater risk of developing this inflammatory complication. Several studies have demonstrated that heparin surface modification of the polymethyl methacrylate (PMMA) lenses render the IOL surface more biocompatible, thus decreasing giant cell formation. The present study compares the postoperative inflammatory response of the heparin surface modified (HSM) IOL to acrylic IOL’s as determined by giant cell formation on the lens surface following phacoemulsification. Methods: This is a parallel, single-masked, randomized, single-center trial. We report the enrollment of 54 patients with diabetes requiring surgery with an indication for implantation of a posterior chamber IOL. The inclusion criteria for enrollment into the study was that patients must be 50 year of age or older, require medical treatment for their diabetes, and must not have proliferative retinopathy or significant macular degeneration. 25 patients received the HSM lens (Pharmacia Co. Model CeeOn 812C HSM) and 28 patients received an acrylic lens (Alcon, Model MB30A). Cataract extraction followed the standard protocol. After surgery, all patients received topical prednisolone acetate 1% to be applied 4 times per day for two weeks, then one time per day for 1 week. Patients were examined at 1 week and 3 and 6 months postoperatively. At each visit, slit lamp examination was performed with pupils dilated to detect the presence or absence of giant cells. Visual acuity and intraocular pressure were also assessed. The anterior surface of the IOL was photographed by specular microscopy at the 3 and 6 month visits for objective determination of giant cells on the lens surface. Results: At the 3 month visit, significantly more patients with the acrylic lens implant had giant cells on the lens surface than those with the HSM IOL by slit lamp examination (p=0.0069) and specular microscopy (p=0.0197). Similarly, at the 6 month visit, significantly more patients with the acrylic lens implant demonstrated giant cell formation on the lens than those with the HSM IOL by slit lamp examination (p=0.0089) and specular microscopy (p=0.0087). Conclusions: HSM lenses (Pharmacia Co. Model CeeOn 812C HSM) exhibited significantly less occurrence of giant cells by both photography and slit lamp observation at the 3 and 6 month postoperative visits after phacoemulsification in diabetic patients.
Keywords: cataract • anterior segment • inflammation