The effectiveness of automatic pupillometry as a screening method to detect diabetic autonomic neuropathy.

Purpose: This study aimed to compare static and dynamic pupil responses of diabetic patients with and without nonproliferative diabetic retinopathy (DR) and normal healthy individuals under different lighting conditions via quantitative automated pupillometry.

Methods: Forty patients with DM with nonproliferative DR (group 1), 40 patients with DM without DR (group 2), and 40 healthy controls (group 3) underwent a complete ophthalmologic examination. Static pupillometry [scotopic pupil diameter (PD), mesopic PD, low photopic PD, and high photopic PD] and dynamic pupillometry (resting PD, contraction amplitude, latency, duration, velocity of contraction, dilatation latency, and duration and velocity at rest) were measured via automatic quantitative pupillometry.

Results: Analysis of variance revealed that scotopic PD [F(2, 117) = 6.42; p = 0.02], mesopic PD [F(2, 117) = 3.20; p = 0.04], and low photopic PD [F(2, 117) = 4.86; p = 0.009] were significantly different among the groups. Scotopic PD and low photopic PD were significantly lower in group 1 than in group 2 (p = 0.03 and p = 0.03, respectively). Meanwhile, the resting diameter, velocity of pupil contraction, and velocity of pupil dilatation were found to be significantly lower (p = 0.02, p = 0.01, and p = 0.008, respectively), and the duration of pupil contraction was significantly higher in group 1 than in group 3 (p = 0.03).

Conclusion: Both DM patients with and without nonproliferative DR exhibited pupillary involvement. Automated pupillometry may be an easily applicable, noninvasive screening option for reducing mortality and morbidity rates associated with diabetic autonomic neuropathy.