Pupillary dynamics in diabetic and nondiabetic patients following uneventful phacoemulsification.

Clinical relevance: Although laser refractive surgeries and multifocal intraocular lens implantation are generally avoided in patients with diabetic retinopathy, a substantial proportion of well-glycaemic-controlled type 2 diabetes mellitus patients are considered for these procedures. Pupil dynamics play a significant role in determining postoperative satisfaction in these patients.

Background: To evaluate pupillary dynamics in patients with and without diabetes following uneventful phacoemulsification surgery.

Method: This retrospective study involved 86 patients with type-2 diabetes and 41 non-diabetic patients undergoing phacoemulsification. Pupillary measurements were performed using the Sirius Topographer (CSO, Firenze, Italy) preoperatively and at the 1-month and 3-month postoperatively. Diabetic patients were categorised into non-diabetic retinopathy (without diabetic retinopathy), non-proliferative diabetic retinopathy (NPDR), and proliferative diabetic retinopathy (PDR) subgroups based on the presence and severity of diabetic retinopathy. Baseline and postoperative pupillometric values were then evaluated for all groups.

Results: Preoperatively, baseline scotopic, mesopic, and photopic pupil diameters, and pupil redilation velocity were smaller in the NPDR and PDR subgroups compared to the control group (p < 0.05, for all). At 1-month postoperatively, pupil diameters in all lighting conditions significantly decreased in both the control and non-diabetic retinopathy groups (p < 0.05, for all), while pupil dilation rate increased (p = 0.011 and p = 0.002, respectively). In the PDR group, a significant increase in photopic pupil diameter was observed at 1 and 3 months postoperatively (p = 0.018 and p = 0.030, respectively). The PDR and NPDR groups showed a significant decrease in postoperative first- and third-month scotopic pupil diameter (p < 0.05, for all).

Conclusion: Pupil diameter was smaller in diabetic patients compared to controls pre-and postoperatively. Patients with non- diabetic retinopathy and NPDR, who already exhibited smaller pupil diameters in all lighting conditions than the controls (in mesopic condition, 3.54 cf. 3.66, and 3.11 cf. 3.66 mm, respectively), experienced a further reduction in pupil size following phacoemulsification.