Comparison of astigmatism after cataract surgery by phacoemulsification and extracapsular techniques in Amir Kabir hospital of Arak

Cataract is one of the most important and a major disease in human. The prevalence of cataract in age 65-74 get to 50%, and over 75 it arrives to 70%. Absolute cure for cataract is surgery that can be done by different techniques such as intracapsular, extracapsular, and phacoemulsification. Cataract surgery has different side effects such as hemorrhage, Glaucoma, posterior capsular opacification and astigmatism. This study decides to compare astigmatism after two techniques of cataract surgery phaco and extracapsular. This study is a double blind randomized clinical trial, which has been experienced on 112 patients. Patients were divided in two groups (A and B). In group A surgery was done by phaco technique which has a small incision of 3.2 mm and does not need suture. But in group B, (extracapsular group) the incision is bigger about 10 mm and needs suture. Then keratometry was done for each patient before surgery, one week and 2 months after surgery for determining astigmatism. Data was analyzed by independent and paired sample T tests. p< 0.05 was considered meaningful. From 112 patients that had been studied, 56 patients underwent phaco technique and 56 patients underwent extracapsular technique. Mean of astigmatism before surgery in group phaco was 0.79±0.71 D and in extracapsular was 0.90.55 D (p>0.05). Mean of astigmatism 1 week after surgery in phaco group was 1.110.72 D and in extracapsular group was 3.991.46 D (p<0.05) and mean of astigmatism two months after surgery in phaco group was 1.00.71 D and in extracapsular group was 3.281.29 D (p<0.05). Induced astigmatism in phaco group was 0.21 D and in extracapsular was 2.38 D, that has meningful difference. Other criteria such as age, lens number, sex and left or right eye do not have any effect on induced astigmatism.