Effects Of Pattern Scanning Laser Panretinal Photocoagulation On Ocular Surface, Corneal Thickness, And Endothelial Parameters
Published 2025 - 43rd Congress of the ESCRS
Reference: PO593 | Type: Free paper | DOI: 10.82333/q5wq-cz82
Authors: Gabriel Santos* 1 , Bruno Barbosa-Ribeiro 1 , João Heitor Marques 2 , Saúl Pires 1 , Paulo Sousa 1 , Pedro Menéres 2 , Irene Barbosa 2
1Neurociences,Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António,Oporto,Portugal, 2Neurociences,Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António,Oporto,Portugal;Opthalmology,Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto,Oporto,Portugal
Purpose
This study aims to evaluate the effects of pattern scanning laser (PASCAL) panretinal photocoagulation (PRP) on the ocular surface, corneal thickness, and endothelial cell parameters in patients with proliferative diabetic retinopathy (PDR).
Setting
Department of Ophthalmology, Bülent Ecevit University, Zonguldak, TURKEY
Methods
This prospective and cross-sectional study included 82 patients diagnosed with PDR. All patients were examined before PRP, at 15 minutes post-procedure, and at 1 month. PRP was performed using the PASCAL Synthesis (Iridex Corporation®, California, USA). Ocular surface assessment included tear breakup time (NIF-BUT and AVG-BUT, measured using Sirius+ Corneal Topographer/Tomograph [C.S.O. SRL, Italy]), corneal staining score (Oxford scale), and Schirmer test. Central corneal thickness (CCT) and endothelial cell parameters were evaluated using the Specular Microscope CEM-530 (Nidek, Japan).
Results
The mean age of the patients was 63.28 ± 10.9 years. A significant decrease in NIF-BUT and AVG-BUT values was observed after PRP (p < 0.01). Corneal staining scores increased significantly (p < 0.001), while Schirmer test values showed no significant change (p > 0.05). CCT increased significantly from 538.50 µm before PRP to 552.00 µm post-PRP and 556.50 µm at 1 month (p < 0.000). Endothelial cell density (CD) decreased significantly post-PRP but showed partial recovery at 1 month (p < 0.01). The coefficient of variation (CoV) of endothelial cell area decreased post-PRP but increased again at 1 month (p < 0.001). A positive correlation was observed between CCT and both PRP energy level (p < 0.01) and the number of laser shots (p < 0.05).
Conclusions
Pattern scanning laser PRP induces changes in ocular surface parameters and negatively affects tear film stability. Additionally, PRP leads to a significant increase in corneal thickness and a transient decrease in endothelial cell density. However, the partial recovery of endothelial cells by the first month suggests that the effects on the corneal endothelium may be reversible over time. Although these changes may not result in prominent clinical symptoms, it is crucial to be aware of these effects prior to performing PRP and to carefully select patients, particularly those with pre-existing ocular surface disease or a low endothelial reserve.