Abstract
Purpose :
Controversy exists regarding the impact of panretinal photocoagulation (PRP) in retinal perfusion in patients with proliferative diabetic retinopathy (PDR). The purpose of this prospective study was to evaluate the changes of foveal avascular zone (FAZ) area and vessel density (VD) in superficial (SCP) and deep capillary plexus (DCP) in association with functional changes in patients with PDR treated with PRP.
Methods :
Participants in this study were 16 patients with PDR and no macular edema, who were eligible for PRP. All participants underwent best-corrected visual acuity (BCVA) measurement, optical coherence tomography (OCT) and OCT angiography (OCTA) at baseline (before treatment) and at months 1 and 3 after completion of PRP treatment. Comparison of OCTA parameters and BCVA between baseline and months 1 and 3 after PRP was performed. Correlation of OCTA parameters and BCVA was also done.
Results :
22 eyes of 16 patients with PDR were included in the study. There was a statistically significant decrease in FAZ area at month 3 of the follow-up period compared to baseline (p<0.001), while no difference was noted at month 1 of the follow-up period (p>0.05). Of note, FAZ became significantly more circular 3 months after PRP (p=0.022). There was no statistically significant difference in VD in both SCP and DCP at month 1 and 3 of the follow-up period (p>0.05 in all comparisons). The FAZ area was associated with BCVA during the whole follow-up period (p<0.001, p=0.014 and p<0.001 for baseline and months 1 and 3 respectively).
Conclusions :
Although VD was not significantly affected by PRP at the short-term follow-up of 3 months in patients with PDR, the FAZ area became significantly more circular and decreased significantly at month 3 of the follow-up period, suggesting that re-distribution of blood flow may occur in hypo-perfused foveal capillary plexus after PRP in patients with PDR.
This is a 2021 ARVO Annual Meeting abstract.