Análise paquimétrica da córnea no pré-operatório e correlação com edema corneano no pós operatório da facoe-mulsificação

Abstract

Introduction: The Cornea is a transparent convex structure with high refractive power. It differs from the sclera by the degree of hydration and the arrangement of collagen fibers. Although it is avascular, which guarantees its transparency, it is richly innervated by fibers from the ophthalmic branch of the trigeminal nerve. Corneal edema is caused by excessive hydration of the cornea, which affects light transmission, refraction, transparency and, consequently, visual performance. The most common cause of edema is phacoemulsification with intraocular lens implantation, which is the most commonly performed surgery in the world for the treatment of cataracts. Factors that may be associated with postoperative corneal edema are: low corneal endothelial cell density (CED), high central corneal thickness (CCE), degree of cataract, effective ultrasound power time, among others. The purpose of this study was to evaluate the influence of ECC, and secondarily of DEC and time of ultrasound use on postoperative corneal edema. Methods: Observational study, covering one hundred patients with grade 2 (N2) nuclear cataracts who underwent the phaco-chop fracture technique. To evaluate the influence of the variables ECC, DEC and time of ultrasound use on postoperative corneal edema, patients were divided into groups according to the presence of corneal edema (yes and no) and the edema classification (0, 1, two). Results: In the study sample, the only associated factor was the effective ultrasound power time (p < 0.0001), with 52% of patients presenting corneal edema in the immediate postoperative period, with a median ultrasound usage time equal to 36 seconds. Conclusion: The results suggest that the longer the time ultrasound is used in surgery, the greater the chance of developing corneal edema postoperatively and the greater the severity of the corneal edema found, while the central corneal thickness and endothelial cell density corneal edema were not associated with the severity of postoperative corneal edema, p = 0.34 and p = 0.11, respectively.