Aim: To evaluate surgically induced astigmatism following cataract surgery with superior scleral incision of different sizes and shapes
Objective: To evaluate the change in astigmatism pre and post cataract surgery using keratometry values
1. With different sizes of scleral incision
2. With different shape of incision (Straight & Frown)
Material and Methods: Study was conducted in SVS Medical College Mahabubnagar. 200 patients who had senile cataract were included in the study. Patients were divided into 4 groups depending on size of superior scleral incision following small incision cataract surgery. Patients were followed up 1, 3 and 6 weeks post cataract surgery. Visual acuity and keratometry readings were recorded. Surgically induced astigmatism was evaluated by simple subtraction method from the pre and post operative keratometry readings. Observations: Our study showed group 1 with 5.5 mm superior scleral incision showed least surgically induced astigmatism. 40 patients (80%) with 5.5 mm incision had < 1 D of SIA compared to 20 patients (40%) with 6.5 mm incision group. 18% of patients with 6.5 mm incision had SIA > 1.6 D, which was high compared to 5.5 mm group which was only 8 %. Comparing straight and frown incision, 6 mm frown incision showed significantly low SIA compared to 6 mm straight incision. 46 % of patients with frown incision showed < 0.5 D SIA which was significantly low compared to 6 mm straight group which had only 24% patients who had < 0.5 D SIA.
Conclusion: Smaller the size of scleral incision less is the surgically induced astigmatism. Frown incision showed less SIA compared to same size straight sclera incision.
