Voluntary Eye Movement Tests in Patients with Insulin-dependent Diabetes Mellitus

Abstract

Eye movement tests (saccade tests: reaction time, peak velocities and accuracy, and the eye tracking test) were studied in 53 insulin-dependent diabetic (IDDM) patients and 42 randomly selected non-diabetic control subjects, aged between 20 and 40 years. All subjects had central visual acuity of at least 0.1 in one eye, and none had ophthalmoplegia. The reaction time was longer and the accuracy decreased in the saccade test in diabetic patients as compared to control subjects. Peak velocities tended to be slower in diabetic patients, but no significant differences between diabetic and non-diabetic subjects were observed. The maximum eye movement velocities were reduced at all target velocities in diabetic patients as compared to control subjects. These findings can be explained on the basis of many potential disturbances in the central nervous system. Only the duration of diabetes had a clear association with maximum smooth pursuit eye movement velocities in the eye tracking test. Microvascular complications (retinopathy, nephropathy), autonomic neuropathy or metabolic control (high fasting blood glucose and glycated hemoglobin A_1c) had no clear association with the results of eye movement tests. In conclusion, insulin dependent diabetes mellitus deteriorates the visuomotor responses.

Key Words:

• saccade test
• eye tracking test
• type 1 diabetes