Persistent avascular retina in retinopathy of prematurity.

Persistent avascular retina (PAR) has been increasingly reported with the increased use of anti-vascular endothelial growth factor (VEGF) agents in treatment-requiring ROP. However, they have also been observed in ROP eyes that did not meet treatment requirement and spontaneously regressed. PAR is highlighted in the updated nomenclature under the International Classification of Retinopathy of Prematurity, 3rd edition (ICROP3) consensus statement, underscoring the increased emphasis in detecting PAR. PAR has been noted to persist beyond existing ROP screening guidelines, and were found to be associated with complications like retinal tear and detachment, especially in eyes with more posterior PAR. Thus, serial monitoring of retinal vascularization, facilitated by fluorescein angiography and wide-field imaging, for these associated complications have been encouraged. The current lack of consensus in the follow-up and management of PAR prompts further work in this area: understanding the natural course of retinal vascularization in both untreated and treated ROP, the modulation of anti-VEGF on retinal function, and the clinical significance of PAR-associated vascular patterns can help to guide management protocols for PAR in ROP eyes.