Background & Method: The present study titled "To study the ocular surface changes in patients of diabetes mellitus"was done in the Department of Ophthalmology, Shyam Shah Medical College, Rewa (M.P.). A total of 350 type 2DM patients were taken in this study in which after fund us examination 133 patients were DM without DR and 217patients were DM with D. All patients were underwent complete ocular examination including visual acuity, lid, conjunctiva, cornea and investigation such as schirmer’s test, TFBUT, and central corneal thickness by AS-OCT. A detailed history was taken including the chief visual complaint, history of present illness, past history, personal history with history of diabetes mellitus and medical history. General examination and systemic examination were done and all positive findings were recorded. Result: A significant correlation (p<0.0001) was found between mean TBUT values and the duration of diabetes. The mean TBUT in patients with a duration >10 years was noted to be 7.44 ± 2.66 and in patients with a duration of < 10 years was 10.84 ± 3.17. The mean TBUT values were seen to have an inverse correlation with the severity of diabetic retinopathy. Patients with no DR had the highest mean TBUT of 12.22 seconds; those with NPDR had a value of 8.27 seconds while those with PDR had a mean value of only 6.40 seconds and the difference across the three groups was statistically significant (p<0.0001). Correlating the Schirmer’s value with duration of diabetes, we observed that the mean value in diabetic patients with more than 10 years duration (8.16 mm) was significantly lower (p<0.0001) than their counterparts with disease duration less than 10 years (13.78 mm). The mean Schirmer’s value also showed a significant (p<0.0001) inverse correlation with severity of diabetic retinopathy. The highest mean value (15.86 mm) was noted in patients with no DR followed by 9.61 mm in NPDR and the lowest value of 6.66 mm in patients with PDR. Analyzing the relationship of mean CCT with duration of diabetes, it was seen that mean CCT was significantly (p<0.0001) higher in patients who had a disease duration of more than 10 years (572.80μ) as compared to those with a duration of less than 10 years (557.66μ). Mean central corneal thickness was also analyzed in relation to the grade of diabetic retinopathy. It was seen that the mean CCT had a direct relation with severity of retinopathy as was evidenced by increasing values from 550.62μ in no DR group to 568.34μ in NPDR group and 582.26μ in the PDR group. This difference in the measurements was statistically significant (p<0.0001). Conclusion: Present study suggest diabetes mellitus show increase schirmer’s test and TFBUT value which leads to dry eye. Dry eye can lead to vision deficit, scarring, perforation of cornea and secondary bacterial infection. Diabetes mellitus have thicker cornea which mask the accurate reading of IOP in glaucoma. Corneal thickness in diabetes mellitus is also important for planning and performing refractive surgery. So, if this syndrome diagnosed earlier and treated, it will be easy to protect from its complication
