Predictive value of Optical Coherance Tomography after Laser Photocoagulation in Clinically Significant Macular Edema

1. Arjun Shrestha, MD
2. Raba Thapa, MD
3. Govinda Poudyal, MD

1. Geta Eye Hospital, Dhagadi, Nepal
2. Tilganga Institute of Ophthalmology, Kathmandu, Nepal
3. Tilganga Institute of Ophthalmology, Kathmandu, Nepal

Purpose: To find out the predictive value of optical coherence tomography mapping of retinal thickness after laser therapy in clinically significant macular edema

Methods: This is a prospective case series study enrolling 54 eyes with diagnoses of clinically significant macular edema.All the patients were given grid and focal laser after which each patient was evaluated in terms of best-corrected visual acuity and regression or progression of maculopathy. Correlation between vision status and Central macular thickness was done with Spearman's correlation test. Analysis of variance was used to compare among groups and independent t-test was used to compare in each group. The criterion for statistical significance was p value ≤0.05.

Results: OCT revealed the sponge like thickening pattern in 67.4 % followed by cystoids macular edema in 19.6 %. BCVA improved in 89.1 % and deteriorated in 10.9 % patients after 6 month of treatment. Spearman's correlation test showed high correlation between vision and central macular thickness(P =<0.001).The Baseline CMT (mean and SD) were 301.68 (134.738), 434.83 (180.758), 518.67 (275.184), 327 (108.393) and 334.85 (158.91) microns for different OCT patterns, ST, CMO, SFD, VMIA and average CMT respectively and they were significantly different (p=0.042).

Conclusion: OCT is a useful tool for evaluating and documenting CSME both before and after laser photocoagulation. It has shown the different morphological variant of CSME while the response of treatment is fairly different. The central macular thickness decreased the most and hence showed the improvement in vision only after 6 months of laser treatment.