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Persistent avascular retina in eyes with retinopathy of prematurity: A comprehensive review
Tomoya Murakami1,2, Eric Nudleman1
1Department of Ophthalmology, Shiley Eye Institute, University of California San Diego, San Diego, California.
Insights
Persistent avascular retina (PAR) is increasingly seen after retinopathy of prematurity (ROP) treatments. PAR may risk ROP reactivation or detachment, necessitating lifelong monitoring and potential laser treatment.
Area of Science:
- Ophthalmology
- Neonatology
- Retinal Vascular Diseases
Background:
- Persistent avascular retina (PAR) is a condition where retinal vascular development halts prematurely in infants.
- The shift in retinopathy of prematurity (ROP) treatment from laser to anti-VEGF therapy has increased PAR observation.
- Emerging evidence links PAR to risks of ROP reactivation, retinal breaks, and detachment.
Purpose of the Study:
- To review current understanding of PAR, including its mechanisms, prevalence, significance, and management.
- To highlight the clinical importance of PAR in regressed ROP cases.
- To inform clinical practice regarding the potential risks associated with PAR.
Main Methods:
- Literature review synthesizing recent research on PAR.
- Analysis of pathophysiologic mechanisms and clinical significance.
- Evaluation of current management strategies and treatment outcomes.
Main Results:
- PAR is frequently observed in ROP eyes treated with anti-VEGF therapy (Type 1 ROP) and those regressing without treatment (Type 2 ROP).
- PAR is associated with potential risks of late ROP reactivation and rhegmatogenous retinal detachment.
- Current management strategies for PAR lack consensus.
Conclusions:
- PAR is a common finding in treated and untreated regressed ROP.
- Lifelong monitoring of eyes with PAR is recommended due to potential late complications.
- Consideration of laser photocoagulation for PAR may be warranted to prevent adverse outcomes.
Abstract:
Persistent avascular retina (PAR) refers to retinal areas where vascular development permanently arrests in premature children. In the last decade, the first-line treatment for retinopathy of prematurity (ROP) has shifted from laser photocoagulation to antivascular endothelial growth factor (VEGF) therapy, leading to the increased observation of PAR in eyes treated for ROP. Emerging evidence suggests that PAR could pose a risk for late reactivation of ROP, retinal breaks, or detachment. Consequently, PAR has emerged as an important finding in eyes of regressed ROP. In this review, we summarize the recent understanding of PAR, including its pathophysiologic mechanism, prevalence, clinical pathological significance, and management. We conclude that PAR can be often observed in eyes treated with anti-VEGF therapy (type 1 ROP) and in those that regress without treatment (type 2 ROP). Current management of PAR lacks consensus; however, since PAR can potentially cause late reactivation or rhegmatogenous retinal detachment after achieving regression of ROP, treatment with laser photocoagulation should be considered, and lifelong monitoring is recommended.
