Comparison of long-term macular morphology after laser retinal photocoagulation and anti-VEGF therapy and their effects on vision prognosis for type 1 ROP

Objective

To evaluate and compare the foveal microvascular morphology and central foveal thickness (CFT) after laser retinal photocoagulation and intravitreal injection of anti-vascular endothelial growth factor (VEGF) in patients with retinopathy of prematurity (ROP), and to explore the factors affecting the prognosis of vision.

Methods

A cohort study was conducted.Forty children (40 eyes) aged 4-6 years, who had been treated in Peking University People’s Hospital for type 1 ROP from January 2019 to December 2020, were enrolled.Optical coherence tomography angiography (OCTA), best corrected visual acuity (BCVA) and refractive status of the patients were examined.The patients were divided into laser retinal photocoagulation group and anti-VEGF group according to they received a single laser retinal photocoagulation therapy or a single intravitreal injection of anti-VEGF drugs (conbercept or ranibizumab 0.25 mg/0.025 mL) after birth. Twenty age-matched full-term healthy children (20 eyes) were enrolled as the normal control group.The FAZ area, superficial and deep foveal vessel density (VD) and CFT of the affected eyes were measured by OCTA at 4-6 years after treatment to investigate the influence of gestational age, birth weight, morphological characteristics of foveal microvessels and CFT on the prognosis of BCVA.This study protocol adhered to the Declaration of Helsinki and was approved by an Ethics Committee of Peking University People’s Hospital (No.2017PHB179-01). Written informed consent was obtained from the guardians prior to any medical examination.

Results

There were statistically significant differences in FAZ area, superficial foveal VD and deep foveal VD among the three groups (F=12.321, 8.436, 5.497; all at P<0.05). The FAZ area was smaller, and the superficial and deep foveal VD of the laser photocoagulation group and the anti-VEGF group were greater than those in the normal control group, and the difference was statistically significant (all at P<0.05). The CFT of the laser photocoagulation group was (267.6±11.8)μm, greater than (259.5±12.9)μm of the anti-VEGF group and (242.4±12.3)μm of normal control group, and the CFT value of the anti-VEGF group was greater than that of the normal control group, and the differences were statistically significant (all at P<0.05). There was a strong negative correlation between the superficial foveal VD and FAZ area (r=-0.713, P<0.05), a moderate negative correlation between the deep foveal VD and FAZ area (r=-0.565, P<0.05), and a moderate positive correlation between gestational age and FAZ area (r=0.485, P<0.05). Pearson correlation analysis results showed that gestational age, FAZ, superficial foveal VD, deep foveal VD, CFT were all correlated with BCVA (all at P<0.05). The effects of gestational age and FAZ on BCVA were both statistically significant (R²=0.615, both at P<0.05).

Conclusions

The morphology of microvessels in macular fovea and the prognosis of BCVA in the affected eye is similar at 4-6 years after laser retinal photocoagulation and intravitreal injection of anti-VEGF drugs for type 1 ROP.The CFT of the affected eye after anti-VEGF drug therapy is better than those after laser retinal photocoagulation.Gestational age and FAZ are the influencing factors of visual acuity after treatment in children with type 1 ROP.

Retinopathy of prematurity; Laser coagulation; Vascular endothelial growth factor; Coherence tomography angiography, optical; Macular fovea; Microvessels; Visual acuity