ABSTRACT: To determine incidence, risk factors, risk period, and characteristics of recurrent retinopathy of prematurity (ROP) treated by intravitreal bevacizumab (IVB) monotherapy.Retrospective case series.Premature infants with type 1 ROP (subdivided into stage 3+ ROP and aggressive posterior ROP [APROP]) in zone I or zone II posterior who received IVB monotherapy and were followed up for at least 65 weeks adjusted age (AA).Retrospective review of infants who demonstrated recurrence of type 1 ROP after IVB monotherapy, including examination of RetCam fundus photographs and fluorescein angiograms.Incidence, risk factors, risk period, and characteristics of recurrent ROP.Intravitreal bevacizumab monotherapy in 241 infants (471 eyes) was reviewed. Recurrence incidence was 8.3% (20/241) for infants and 7.2% (34/471) for eyes. Recurrence risk factors of greatest significance were appearance of neovascularization as APROP (P = 0.006), extended duration of hospitalization (P = 0.01), and lower birth weight (P = 0.024). Recurrence risk period was between approximately 45 and 55 weeks AA (90.0% [18/20] for infants and 94.1% [32/34] for eyes), with mean recurrence of 51.2 weeks AA (±4.6 weeks; range, 45.7-64.9 weeks) and mean interval of 16.2 weeks (±4.4 weeks) between treatments. Recurrence characteristics included plus disease (20/20 infants [100%]) and neovascularization, which appeared at the following sites: stage 3+ ROP with confluent neovascularization recurred both at the advancing edge and at the initial ridge and extraretinal fibrovascular proliferative complex (12/14 infants [85.7%]). However, APROP (6/6 infants [100%]) and stage 3+ ROP with nonconfluent neovascularization (2/14 infants [14.3%]) recurred only at the advancing edge. Also, the anterior extent of retinal vascularization was decreased (mean, 1.76 disc diameters [DD] vs. 4.48 DD), and the rate of retinal vascularization was delayed (mean, 0.11 DD/week vs. 0.23 DD/week) in those with versus without recurrence, respectively. After retreatment with IVB, retinal vascularization proceeded minimally and slowly.Premature children with severe ROP are being treated successfully with IVB monotherapy. However, recurrence is not uncommon, so vigilant follow-up is necessary to ensure timely re-treatment. Knowledge of recurrence incidence, risk factors, risk period, and characteristics allows for tailored clinical management.
