Corneal Endotheleal Cells Changes after Phacoemulsification in Type II Diabetes Mellitus

Abstract

Background: Corneal endothelial cells are responsible for the clarity of the cornea; however, endothelial cells have limited cell division ability. Studies have proven that cornea is more vulnerable to chronic changes affecting endothelial cells in diabetic patients. Cataract extraction by phacoemulsification is one of the most ophthalmic surgeries having a negative effect on the corneal endothelial cells especially in elders. Age of the patient and diabetes mellitus have a negative effect on the outcome of phacoemulsification. The aim of the study is to compare the changes occur in corneal endothelium pre and post cataract extraction by phacoemulsification in diabetic patients in aspects of BCVA, CCT, CD, CV and HEX. Aim of the work: To assess endothelial cells changes following cataract extraction by phacoemulsification and posterior chamber IOL implantation in type II diabetic patients. Methods: The study included 20 eyes of 20 patients scheduled for cataract surgery by phacoemulsification at Al Azhar university hospitals. The patients were assigned to 2 groups. Group 1: Ten patients without diabetes were used as a control group, and a casual blood glucose test and glucose tolerance test were undertaken in accordance with the recommendations of the American Diabetes Association to disclose undetected diabetes. Group 2: Ten patients diagnosed with type II diabetes based on medical history and all were on oral anti-diabetic medication or subcutaneous treatment with insulin. Serum glycosylated hemoglobin (HbA1c) was obtained in all patients with diabetes to evaluate their glycemic status.In this prospective randomized study we did Preoperative specular microscopy and serial postoperative specular microscopy ( Topcon SP- 1P,Topcon Medical Inc., Japan).) were performed to evaluate endothelial cell count changes over 6 months. Endothelial cell images were collected in the central region of the cornea before surgery and 1 and 6 months after surgery. The main outcome measures were central corneal thickness (CCT), cell density (CD), coefficient of variation (CV), hexagonality (HEX) and best corrected visual acuity (BCVA). Results: In term of CCT, in group 1 the CCT mean ±SD in preoperative is 510.7 ±35.13, in 1 month postoperative is 522.1 ±35.91 and in 6 months postoperative is 512 ±34.91, the difference between preoperative CCT and 6 months postoperative is 1.3 ±0.95. In group 2 the CCT mean ±SD in preoperative is 497.45 ±25.82, in 1 month postoperative 515.64 ±26.59 and in 6 months postoperative is 500.18 ±25.5, the difference between preoperative CCT and 6 months postoperative is 2.73 ±1.64. In term of CD, in group 1 the CD mean ±SD in preoperative is 2678 ±390, in 1 month postoperative is 2599 ±378 and in 6 months postoperative is 2571 ±355, the difference between preoperative CD and 6 months postoperative is -107.17 ±15.53. In group 2 the CD mean ±SD in preoperative is 2872 ±335, in 1 month postoperative is 2703 ±326 and in 6 months postoperative is 2441 ±284, the difference between preoperative CD and 6 months postoperative is -430.8 ±50.31. In term of CV, in group 1 the CV mean ±SD in preoperative CV is 34.4 ±2.95, in 1 month postoperative is 35.2 ±3.05 and in 6 months postoperative is 35 ±2.6, the difference between preoperative CV and 6 months postoperative is 0.7 ± 1.34 which is statistically insignificant. In group 2 the CV mean ±SD in preoperative CV is 36 ±3, in 1 month postoperative is 37 ±3.16 and in months postoperative is 36 ±3.2, the difference between preoperative CV and 6 months postoperative is -0.3 ±1.64 which is statistically insignificant. In term of HEX, in group 1 the HEX mean ±SD in preoperative is 34 ±8, in 1 month postoperative 29 ±7 and in 6 months postoperative 28 ±7, the difference between preoperative and 6 months postoperative is -6.2 ±1.55 which is statistically significant. In group 2 the mean HEX mean ±SD in preoperative is 33 ±10, in 1 month postoperative is 25 ±7 and in 6 months postoperative is 24 ±7, the difference between preoperative HEX and 6 months postoperative is -8.7 ±2.58 which is statistically significant. In term of BCVA, in group 1 the BCVA mean ±SD in preoperative is 0.15 ±0.05, in 1 month postoperative is 0.38 ±0.11 and in 6 months postoperative is 0.5 ±0.07, the difference between preoperative BCVA and 6 months postoperatively is statistically significant. In group 2 the BCVA mean ±SD in preoperative is 0.128 ±0.034, in 1 month postoperative is 0.285 ±0.0369 and in 6 months postoperative is 0.392 ±0.093, the difference between preoperative BCVA and 6 months postoperatively is statistically significant. Conclusion: The endothelium in diabetic subjects is more vulnerable to surgical trauma and has a lower capability in the process of repair.