Materials and Methods: We studied the effect of short term changes in blood glucose level on the lens thickness, anterior chamber depth and axial length in 21 eyes of 11 diabetic patients (group 1) and the effect of regulation of blood glucose level on the lens thickness, anterior chamber depth and axial length in 20 eyes of 10 diabetic patients (group 2). All the patients were on insulin therapy. In the 1st group blood glucose determinations were done with a time interval of 4 hours and at the same time biometric measurements were taken. In the 2nd group first biometric measurements were taken while the blood glucose levels were irregular. The second measurements were taken after we measured the starving blood glucose level under 150 mg/ml and satiety blood glucose level under 200 mg/ml for 5 days.

Results: In the 1st group the blood glucose levels were measured as 183.5±71 mg/ml and 190.8±75 mg/ml with a time interval of 4 hours. Although there was an increase of 7.3 mg/ml in the blood glucose level, we detected a 0.02 mm increase in lens thickness and a 0.07 mm decrease in anterior chamber depth and axial length. There was no statistically significant difference between the changes in blood glucose level and the changes in lens thickness, anterior chamber depth and axial length (p>0.01). In the 2nd group we found a decrease of 0.04 mm in lens thickness and an increase of 0.07 mm in anterior chamber depth and 0.16 mm in the axial length after the blood glucose levels were regulated, but the differences were again not statistically significant (p>0.01).

Conclusion: The changes in the lens thickness, anterior chamber depth and axial length occuring in respect to change in blood glucose level are not statistically significant. So we think that the refractive changes seen in diabetic patients should be rather correlated with the changes in refractory media. Keywords : Blood glucose level, lens thickness, anterior chamber depth, axial length