The Effect of Pattern Scan Laser Photocoagulation on Peripapillary Retinal Nerve Fiber Layer Thickness and Optic Nerve Morphology in Diabetic Retinopathy

Purpose

To evaluate the effect of pattern scan laser (PASCAL) photocoagulation on peripapillary retinal nerve fiber layer (RNFL) thickness, central macular thickness (CMT), and optic nerve morphology in patients with diabetic retinopathy.

Methods

Subjects included 35 eyes for the PASCAL group and 49 eyes for a control group. Peripapillary RNFL thickness, cup-disc area ratio and CMT were measured before PASCAL photocoagulation and at 2 and 6 months after PASCAL photocoagulation in the PASCAL or control groups.

Results

The average RNFL thickness had increased by 0.84 µm two months after and decreased by 0.4 µm six months after PASCAL photocoagulation compared to baseline, but these changes were not significant (p = 0.83, 0.39). The cup-disc area ratio was unchanged after PASCAL photocoagulation. CMT increased by 18.11 µm (p = 0.048) at two months compared to baseline thickness, and partially recovered to 11.82 µm (p = 0.11) at six months in the PASCAL group.

Conclusions

PASCAL photocoagulation may not cause significant change in the peripapillary RNFL thickness, CMT, and optic nerve morphology in patients with diabetic retinopathy.