Prolonged follow-up period following intravitreal bevacizumab injection for stage 3+ retinopathy of prematurity

Sir,

Data from the Beat-ROP study indicate that bevacizumab (Avastin; Genentech Inc., South San Francisco, CA, USA) treatment results in a lower rate of retreatment compared with conventional laser treatment for Zone 1 retinopathy of prematurity (ROP).¹ However, the suppression of angiogenesis means that follow-up until vascularisation into Zone 3 can be dramatically prolonged, as it was with the case we present here.

Case report

A female, born at 22 weeks and 6 days gestational age (birth weight 535 g), had initial ROP screening at 30+4 weeks when retinal vascularisation was only present in Zone 1 in both eyes (BE). At 33+3 weeks corrected gestational age (CGA), the left eye was graded as ROP stage 3 in Zone 1 with plus disease, while the right eye was graded Zone 1 stage 2 with plus disease. Both pupils dilated poorly with persistent tunica vasculosa lentis, and 0.625 mg bevacizumab was injected intravitreally bilaterally. By 2 weeks the disease had regressed bilaterally to stage 1 with pre-plus features only.

Retinal vascularisation progressed extremely slowly into Zone 2, and weekly examination had to be continued until 50 weeks CGA. The child was then reviewed 2 weekly until 58 weeks CGA when the retinal vascularisation was completed.

Comment

The anti-VEGF injections proved highly effective at suppressing the ROP process, but delayed normal retinal vascularisation necessitating follow-up for 35 weeks. If this treatment becomes widely used, it will place an increased burden on ophthalmologists involved in ROP management as well as on parents who will be required to bring back infants long after discharge. The natural history of ROP progression after treatment with anti-VEGF agents is less well understood and the safe follow-up duration has yet to be defined. In contrast, following laser treatment, permanent regression can be more confidently ascertained despite incomplete vascularisation beyond the ridge.

Wu et al² also mentioned an average follow-up period of 8.34 months for their 23 patients who were reviewed until full retinal vascularisation was seen, thus indicating a requirement for prolonged follow-up.

We feel patients for single modality anti-VEGF treatment should be carefully selected and the likely need for prolonged follow-up taken into consideration when making management decisions.

The authors declare no conflict of interest.