During the last few years, the use of anti-vascular endothelial growth factor (VEGF) drugs in the treatment of acute phase severe retinopathy of prematurity (ROP) has increased around the world, although we are only beginning to learn more about possible long-term ocular and systemic side effects. Ocular effects have included reactivation of the disease and late retinal detachment in eyes treated with anti-VEGFs,1–4 an increased incidence of both macular and peripheral retinal changes on fluorescein angiography (FA),5–7 and a lower incidence of abnormal refractive errors.8 In addition, there are recent reports of increased neurodevelopmental problems in children who were treated with bevacizumab (Avastin; Genentech, South San Francisco, CA) versus laser treated.9–11 Furthermore, there is an increasing concern about systemic side effects due to anti-angiogenetic effect in developing neurons, lungs, and other systems, as stated in many recent studies.12–14
In 2014, we reported a case series of FA studies in 21 infants who developed Type 1, zone I ROP in each eye with one eye randomly assigned to receive intravitreal bevacizumab (0.5 mg bevacizumab in a 0.02 mL basic salt solution); the fellow eyes received peripheral retinal photoablation using 810-nm laser (Iridex, Mountain View, CA).15 When FA was performed at 9 months and age 4 years after treatment, bevacizumab-treated eyes showed more significant vascular and macular abnormalities compared with laser-treated eyes.5 We now report the best-corrected visual acuity (BCVA), optical coherence tomography (OCT), and OCT angiography (OCTA) in most of the same 21 children in the earlier reports at 4 years after treatment.
Patients and Methods
This report is a follow-up study of a single-center, randomized, controlled trial that enrolled subjects from September 1, 2009, to March 31, 2012, at the at the Agostino Gemelli University Hospital in Rome, Italy. All inborn babies with Type 1 zone 1 ROP, as defined by Early Treatment for Retinopathy of Prematurity trial criteria,16 were included in the study. The institutional review board at the Catholic University of Sacred Heart of Rome approved the study protocol, and the trial was registered at the EudraCT number 2009-012609-20, protocol number 343/09 April 24, 2009. Written informed consent was obtained from the parents/guardians of the children.
In brief, treatment and evaluation were performed under general anesthesia with fundus images video-digital FA obtained using the RetCam III imaging system (Natus Medical Incorporated, Pleasanton, CA). Images were captured using a widefield 130° lens, and FA was performed using a bolus of 10% fluorescein solution intravenously administered at a dose of 0.1 mL/kg, followed by an isotonic saline flush. The patients were followed serially with binocular indirect ophthalmoscopy with FA added at 9 months and 4 years under general anesthesia using the same FA protocol.
For this report, BCVAs were assessed by experience examiners17 using LEA symbols acuity test, and cycloplegic refractions were obtained using Retinomax autorefractor (Righton Ophthalmic Instruments, Tokyo, Japan). In patients with nystagmus, monocular visual acuity (VA) testing was performed using a partial optical blurring technique. Means and standard deviation were calculated using the logarithm of the minimal angle of resolution (logMAR) for VA and spherical equivalent for refraction.
In addition, spectral-domain OCT was performed on some awake children at the 4-year examination using Cirrus HD-OCT 500 device (Carl Zeiss Meditec, Jena, Germany). OCT imaging was performed using high-definition 5-line raster with 0° scan angle, 0.25-mm spacing, and 6 mm length. OCT angiographies were performed using 3 mm × 3 mm angiography scan centered on the fovea. From the OCTA images, the superficial retinal layer was imaged from the internal limiting membrane to the inner plexiform layer. OCT scans were performed by an experienced operator (LO), and all scans were reviewed by DL. ImageJ software version 2.0.0-rc-68/1.52h (NIH, Bethesda, MD) was used to perform the subsequent analysis and evaluation of foveal measures (central foveal width, central foveal depression, central foveal thickness, thickness of inner layer, thickness of outer layer), which were collected as pixels and manually measured. The central foveal width was defined as the horizontal distance between foveal crests, identified as the maximum retinal thickness nearest to the foveal reflex on the nasal and temporal side. The central foveal depth was defined as the vertical distance between the deepest point of the fovea and the line that joins foveal crests. The central foveal thickness (CFT) was defined as the thickness of the entire retina from the inner aspect of the inner limiting membrane (ILM) to the Bruch's membrane at the foveal center. The inner retinal layer was defined as the distance from the ILM to the inner border of the outer plexiform layer (OPL). The outer retinal layer was defined as the distance between the inner border of the OPL and the inner border of the retinal pigment epithelium (RPE).
All statistical analyses were performed using R software version 3.4.3 (The R Foundation for Statistical Computing, R Core Team, Vienna, Austria). Two-sided P values and 95% confidence intervals (CIs) were calculated. Visual outcome variables (BCVA in logMAR) were correlated using bivariate Pearson correlation with OCT parameters among all scanned eyes and among two groups of eyes in the base of their treatment.
From among the cohort of 21 Caucasian children enrolled in the study, 18 returned for the 4-year examination, one child had died at 9 months of age due to pulmonary complications, and two children were lost to follow-up. The demographic characteristics of the overall original cohort were not significantly different from the cohort reported here in terms of sex (11 male and 10 female vs. nine male and nine female), birth weight (661.4 grams of the original cohort vs. 664.4 grams of the current report), gestational age (25.53 weeks of the original cohort vs. 25.44 weeks of the current report), and ROP severity (34 stage 3 zone 1 no plus and 8 stage 3 zone 1 plus vs. 30 stage 3 zone 1 no plus and 6 stage 3 zone 1 with plus).
Among these 18 children, six provided acceptable quality OCT and OCTA scans in both eyes; one patient succeeded in providing an OCT exam only in the lasered eye because of nystagmus. Many OCTA scans had significant artifacts for the same reason.
Overall, mean BCVA of the 18 eyes treated with bevacizumab was 0.61 ± 0.36 (mean ± standard deviation) (Snellen 20/80) compared to laser-treated eyes 0.71 ± 0.43 (Snellen 20/100) without statistical significance (mean VA difference −0.09; 95% CI, −0.31 to +0.12; P = .360) (Table 1).
logMAR Visual Acuity and Spherical Equivalent Refraction in BevacizumabVersus Laser Groups
Mean cycloplegic spherical equivalent refractions were not different between the eyes treated with bevacizumab (0.18 ± 3.04) and laser-treated eyes (−0.64 ± 4.55) (mean SER difference 0.82D; 95% CI, −0.90 to +2.53; P = .328). In this sample, six of 18 patients had anisometropia of 4 or more diopters with poor acuity in the more ametropic eye (Table 1).
OCT scans showed no different foveal measures comparing the seven bevacizumab-treated eyes and six laser-treated eyes (Table 2). 95% CI of the difference in means between matched group (excluding the baby who underwent OCT in one eye) showed statistical significance only in foveal thickness in which IVB eyes were thinner than laser-treated eyes (mean CFT difference: −5.33 pixels; 95% CI, −9.62 to −1.05).
Morphological OCT Findings in Bevacizumab Versus Laser Groups
In the six subjects who underwent OCT and OCTA evaluation in both eyes, FA showed the presence of a clearly evident foveal avascular zone (FAZ) area, whereas the OCTA did not show a clear avascular area corresponding to the fovea (Figure 1).
Fluorescein angiography images, optical coherence tomography (OCT) angiographies, and B-scan OCTs in eyes treated with bevacizumab on the right compared with the fellow laser-treated eyes on the left in Patients 2, 4, 7, 10, 11, and 18. Visual acuity of each eye is also reported on the top right.
Univariate regression analysis determined that logMAR BCVA was correlated negatively with central CFTs (R= −0.575; P = .040) and thickness of outer retina (R= −0.739; P = .004). No significant correlations between logMAR BCVA and other morphologic parameters were observed. When analyzing the two groups, only the thickness of the internal retina of the eyes treated with bevacizumab is negatively correlated with logMAR BCVA (R= −0.868; P = .011) (Table 3).
Univariate Regression Analysis for OCT Parameters Correlated With BCVA (logMAR)
In the current report, we provide VA and refractive data along with OCT findings in a small cohort of 18 4-year-old children who were treated in one eye with bevacizumab and the fellow eye with laser for Type 1, zone I ROP. As shown in Table 1, VA was similar (95% CI, −0.31 to +0.12), and we have provided first looks at the longer-term structural changes in IVB- and laser-treated eyes in this unique cohort. In previous studies, the degree of macular thickness was not correlated with VA,18,19 and our findings agree with the concept that abnormal foveal morphology is not consistently associated with a reduction in VA.18
In this study, we employed a table-mounted OCT usable only in older and collaborating children since it requires a compliant patient who can sit upright and fixate on target inside the instrument. Lately, the development of handheld OCT has expanded our understanding of the developing retina through in vivo scans of the foveal microstructure. Before such instrumentation, analysis of the fovea in newborns was possible only with postmortem histologic studies20 with potential fixation artifacts.21 Foveal development is a notably intricate process that begins around 22 weeks PMA and continues throughout childhood with enormous variability among single individuals.22 The inner and outer retinal layers of the fovea develop independently of one other. The elements of the inner retina all reach near full maturity at term birth. In contrast, at this time the outer retinal structures are immature, and the maturation of the photoreceptor layers starts at the age of some postnatal weeks and reach near-full to full maturity at 1 to 3 years of age.23 The fovea is the last retinal region to reach full maturity, and during its formation, inner retinal cells move centrifugally from the fovea and cones migrate centripetally.24,25 This migration process seems to be slower in preterm infants, and prematurity and development of vasculature seem likely to be the cause of the decreased foveal depression in preterm babies.26–28 In the eyes reported here, CFTs are thicker in the eyes treated with laser. The foveal pits are usually wider and shallower in patients with ROP;29 in our cohort this feature tends to be more evident (albeit not statistically significant) in the laser-treated eyes compared to eyes treated with bevacizumab. Based on this small sample we could hypothesize that anti-VEGF therapy enables a different if more physiological foveal development.
Overall, the refractive errors were similar, though one-third of the patients (six of 18) had significant anisometropia (Table 1). This anisometropia may explain some of the observed differences in VA. Many studies suggest that refractive errors that may occur in ROP eyes have probably multifactorial etiology, and the main contributing factors seem to be prematurity, the severity of ROP and treatment administered for ROP.30 In the BEAT-ROP study, bevacizumab-treated infants were found at age 2 years to have significantly lower average myopia compared to those receiving laser photocoagulation.8 Furthermore, one study reported a significantly higher chance of the development of high myopia using bevacizumab compared to ranibizumab.31
There were several limitations of this study. The small sample size of the original population was further reduced by the loss in follow-up and by the difficulties in performing OCT and OCTA in these children. This illustrates the complexity of undertaking long-term follow-up in a preterm population, in part due to the logistics of the social situation of the families (eg, two of the children have emigrated from Italy since their NICU stay) and partly related to the high complexity of neurological and behavioral conditions seen in this population. The neurological conditions of many children also affected their ability to undergo OCT and especially OCTA. However, we were able to obtain VA measurement using the Lea Symbols test in each patient despite complicated neurological status.
One of the strengths of this study is the within-subject randomization scheme that may have lowered the differences between the two treatments, but this approach does eliminate the complexity introduced by the variability of the central nervous conditions in the preterm children that would have been a potentially confounding factor of an across-subject randomization.
Another strength of this study is that OCT and OCTA images were obtained in children at 4 years after randomization to laser versus bevacizumab within each patient. This allows the comparison of retinal structure between the eyes with favorable structural outcomes. A major finding of this study and of previous report on FA5,15 is that using FA clearly provides details about the retinal and choroid circulation together with foveal/macular region vascularization, especially the presence of the FAZ.32
Images provided by OCTA did not show a clearly defined avascular zone compared to the clearly evident FAZ seen in FA (Figure 1). We can only speculate that the difference between FA and OCTA could be due to the low-resolution FA not demonstrating the small and poorly perfused foveal vessels seen in the OCTA. This study also shows that performing OCTA imaging in former preterm children is challenging, in particular, in the presence of nystagmus. In the future faster handheld OCTA may make it possible to acquire images under mild sedation.33 At the moment, although FA images are more familiar and therefore understandable, OCTA structural findings need more study to be correctly interpreted and correlated with FA and color fundus findings.
This study highlights the urgent need for follow-up in the population of preterm infants who undergo treatment for severe ROP with intravitreal anti-VEGF drugs. Although the complexity of this subject population in our small series of extremely premature infants makes it difficult to draw conclusions, the absence of information on the long-term ocular and systemic effects of VEGF blockade in the first months after preterm birth raises serious concerns about the use of this treatment in preterm populations considering the vastly different at risk populations throughout the world.34
- Snyder LL, Garcia-Gonzalez JM, Shapiro MJ, Blair MP. Very Late Reactivation of Retinopathy of Prematurity After Monotherapy With Intravitreal Bevacizumab. Ophthalmic Surg Lasers Imaging Retina. 2016;47(3):280–283. doi:10.3928/23258160-20160229-12 [CrossRef] PMID:26985803
- van der Reis MI, La Heij EC, De Jong-Hesse Y, Ringens PJ, Hendrikse F, Schouten JSAG. A systematic review of the adverse events of intravitreal anti-vascular endothelial growth factor injections. Retina. 2011;31(8):1449–1469. doi:10.1097/IAE.0b013e3182278ab4 [CrossRef] PMID:21817960
- Hajrasouliha AR, Garcia-Gonzales JM, Shapiro MJ, Yoon H, Blair MP. Reactivation of Retinopathy of Prematurity Three Years After Treatment With Bevacizumab. Ophthalmic Surg Lasers Imaging Retina. 2017;48(3):255–259. doi:10.3928/23258160-20170301-10 [CrossRef] PMID:28297039
- Ji MH, Moshfeghi DM, Callaway NF, et al. Retinopathy of Prematurity Reactivated 28 Months after Injection of Ranibizumab. Ophthalmol Retina. 2019;3(10):913–915. doi:10.1016/j.oret.2019.06.017 [CrossRef] PMID:31474514
- Lepore D, Quinn GE, Molle F, et al. Follow-up to Age 4 Years of Treatment of Type 1 Retinopathy of Prematurity Intravitreal Bevacizumab Injection versus Laser: Fluorescein Angiographic Findings. Ophthalmology. 2018;125(2):218–226. doi:10.1016/j.ophtha.2017.08.005 [CrossRef] PMID:28867130
- Henaine-Berra A, Garcia-Aguirre G, Quiroz-Mercado H, Martinez-Castellanos MA. Retinal fluorescein angiographic changes following intravitreal anti-VEGF therapy. J AAPOS. 2014;18(2):120–123. doi:10.1016/j.jaapos.2013.12.009 [CrossRef] PMID:24698606
- Klufas MA, Patel SN, Ryan MC, et al. Influence of Fluorescein Angiography on the Diagnosis and Management of Retinopathy of Prematurity. Ophthalmology. 2015;122(8):1601–1608. doi:10.1016/j.ophtha.2015.04.023 [CrossRef] PMID:26028345
- Geloneck MM, Chuang AZ, Clark WL, et al. BEAT-ROP Cooperative Group. Refractive outcomes following bevacizumab monotherapy compared with conventional laser treatment: a randomized clinical trial. JAMA Ophthalmol. 2014;132(11):1327–1333. doi:10.1001/jamaophthalmol.2014.2772 [CrossRef] PMID:25103848
- Morin J, Luu TM, Superstein R, et al. Canadian Neonatal Network and the Canadian Neonatal Follow-Up Network Investigators. Neurodevelopmental Outcomes Following Bevacizumab Injections for Retinopathy of Prematurity. Pediatrics. 2016;137(4):e20153218–e20153218. doi:10.1542/peds.2015-3218 [CrossRef] PMID:27244705
- Lien R, Yu MH, Hsu KH, et al. Neurodevelopmental Outcomes in Infants with Retinopathy of Prematurity and Bevacizumab Treatment. PLoS One. 2016;11(1):e0148019. doi:10.1371/journal.pone.0148019 [CrossRef] PMID:26815000
- Lepore D, Ji MH, Quinn G. Reply. Ophthalmology. 2018;125(10):e71–e72. doi:10.1016/j.ophtha.2018.04.012 [CrossRef] PMID:30243342
- Lee JY, Chae JB, Yang SJ, Yoon YH, Kim JG. Effects of intravitreal bevacizumab and laser in retinopathy of prematurity therapy on the development of peripheral retinal vessels. Graefes Arch Clin Exp Ophthalmol. 2010;248(9):1257–1262. doi:10.1007/s00417-010-1375-0 [CrossRef] PMID:20393741
- Kusaka S, Shima C, Wada K, et al. Efficacy of intravitreal injection of bevacizumab for severe retinopathy of prematurity: a pilot study. Br J Ophthalmol. 2008;92(11):1450–1455. doi:10.1136/bjo.2008.140657 [CrossRef] PMID:18621796
- Lalwani GA, Berrocal AM, Murray TG, et al. Off-label use of intravitreal bevacizumab (Avastin) for salvage treatment in progressive threshold retinopathy of prematurity. Retina. 2008;28(3)(suppl):S13–S18. doi:10.1097/IAE.0b013e3181644ad2 [CrossRef] PMID:18317338
- Lepore D, Quinn GE, Molle F, et al. Intravitreal bevacizumab versus laser treatment in type 1 retinopathy of prematurity: report on fluorescein angiographic findings. Ophthalmology. 2014;121(11):2212–2219. doi:10.1016/j.ophtha.2014.05.015 [CrossRef] PMID:25001158
- Early Treatment For Retinopathy Of Prematurity Cooperative Group. Revised indications for the treatment of retinopathy of prematurity: results of the early treatment for retinopathy of prematurity randomized trial. Arch Ophthalmol. 2003;121:1684–1694. doi:10.1001/archopht.121.12.1684 [CrossRef] PMID: 14662586
- Ricci D, Cesarini L, Romeo DMM, et al. Visual function at 35 and 40 weeks' postmenstrual age in low-risk preterm infants. Pediatrics. 2008;122(6):e1193–e1198. doi:10.1542/peds.2008-1888 [CrossRef] PMID:19047222
- Marmor MF, Choi SS, Zawadzki RJ, Werner JS. Visual insignificance of the foveal pit: reassessment of foveal hypoplasia as fovea plana. Arch Ophthalmol. 2008;126(7):907–913. doi:10.1001/archopht.126.7.907 [CrossRef] PMID: 18625935
- Akerblom H, Larsson E, Eriksson U, Holmström G. Central macular thickness is correlated with gestational age at birth in prematurely born children. Br J Ophthalmol. 2011;95(6):799–803. doi:10.1136/bjo.2010.184747 [CrossRef] PMID:20974631
- Vogel RN, Strampe M, Fagbemi OE, et al. Foveal Development in Infants Treated with Bevacizumab or Laser Photocoagulation for Retinopathy of Prematurity. Ophthalmology. 2018;125(3):444–452. doi:10.1016/j.ophtha.2017.09.020 [CrossRef] PMID:29103792
- Vajzovic L, Hendrickson AE, O'Connell RV, et al. Maturation of the human fovea: correlation of spectral-domain optical coherence tomography findings with histology. Am J Ophthalmol. 2012;154(5):779–789.e2. doi:10.1016/j.ajo.2012.05.004 [CrossRef] PMID:22898189
- Dubis AM, Costakos DM, Subramaniam CD, et al. Evaluation of normal human foveal development using optical coherence tomography and histologic examination. Arch Ophthalmol. 2012;130(10):1291–1300. doi:10.1001/archophthalmol.2012.2270 [CrossRef] PMID:23044942
- Sjöstrand J, Popovic Z. A time-line model of developmental events within the human fovea based on imaging and histology data. Acta Ophthalmol. 2013;91(s252). doi:10.1111/j.1755-3768.2013.S100.x [CrossRef]
- Hendrickson AE, Yuodelis C. The morphological development of the human fovea. Ophthalmology. 1984;91(6):603–612. doi:10.1016/S0161-6420(84)34247-6 [CrossRef] PMID:6462623
- Yuodelis C, Hendrickson A. A qualitative and quantitative analysis of the human fovea during development. Vision Res. 1986;26(6):847–855. doi:10.1016/0042-6989(86)90143-4 [CrossRef] PMID:3750868
- Ecsedy M, Szamosi A, Karkó C, et al. A comparison of macular structure imaged by optical coherence tomography in preterm and full-term children. Invest Ophthalmol Vis Sci. 2007;48(11):5207–5211. doi:10.1167/iovs.06-1199 [CrossRef] PMID:17962475
- Kozulin P, Natoli R, O'Brien KMB, Madigan MC, Provis JM. Differential expression of anti-angiogenic factors and guidance genes in the developing macula. Mol Vis. 2009;15:45–59. Epub 2009 Jan 12. PMID: 19145251
- Yanni SE, Wang J, Chan M, et al. Foveal avascular zone and foveal pit formation after preterm birth. Br J Ophthalmol. 2012;96(7):961–966. doi:10.1136/bjophthalmol-2012-301612 [CrossRef] PMID:22544530
- Hammer DX, Iftimia NV, Ferguson RD, et al. Foveal fine structure in retinopathy of prematurity: an adaptive optics Fourier domain optical coherence tomography study. Invest Ophthalmol Vis Sci. 2008;49(5):2061–2070. doi:10.1167/iovs.07-1228 [CrossRef] PMID:18223243
- Mintz-Hittner HA, Geloneck MM. Review of effects of anti-VEGF treatment on refractive error. Eye Brain. 2016;8:135–140. doi:10.2147/EB.S99306 [CrossRef] PMID:28539808
- Chen SN, Lian I, Hwang YC, et al. Intravitreal anti-vascular endothelial growth factor treatment for retinopathy of prematurity: comparison between Ranibizumab and Bevacizumab. Retina. 2015;35(4):667–674. doi:10.1097/IAE.0000000000000380 [CrossRef] PMID:25462435
- Lepore D, Molle F, Pagliara MM, et al. Atlas of fluorescein angiographic findings in eyes undergoing laser for retinopathy of prematurity. Ophthalmology. 2011;118(1):168–175. doi:10.1016/j.ophtha.2010.04.021 [CrossRef] PMID:20709401
- Campbell JP, Nudleman E, Yang J, et al. Handheld optical coherence tomography angiography and ultra-wide-field optical coherence tomography in retinopathy of prematurity. JAMA Ophthalmol. 2017;135(9):977–981. doi:10.1001/jamaophthalmol.2017.2481 [CrossRef] PMID:28750113
- Quinn GE, Darlow BA. Concerns for Development After Bevacizumab Treatment of ROP. Pediatrics. 2016;137(4). pii: e20160057. doi:10.1542/peds.2016-0057 [CrossRef] PMID: 27244707
logMAR Visual Acuity and Spherical Equivalent Refraction in BevacizumabVersus Laser Groups
|Patient No.||VA IVB||VA Laser||SER IVB||SER Laser|
|Mean ± SD||0.61 ± 0.36||0.71 ± 0.43||0.18 ± 3.04||−0.64 ± 4.55|
Morphological OCT Findings in Bevacizumab Versus Laser Groups
|Patient No.||Foveal Width IVB (Pixels)||Foveal Width Laser (Pixels)||Foveal Depression IVB (Pixels)||Foveal Depression Laser (Pixels)||Foveal Thickness IVB (Pixels)||Foveal Thickness Laser (Pixels)||Thickness of Inner Layer IVB (Pixels)||Thickness of Inner Layer Laser (Pixels)||Thickness of Outer Layer IVB (Pixels)||Thickness of Outer Layer Laser (Pixels)|
|Mean ± SD, No.||132.85 ± 82.91 (7)||152.81 ± 78.03 (6)||8.56 ± 4.95 (7)||5.91 ± 3.60 (6)||40.14 ± 11.31 (7)||49.50 ± 19.94 (6)||13.06 ± 4.44 (7)||14.98 ± 6.50 (6)||27.11 ± 10.20 (7)||34.52 ± 14.07(6)|
Univariate Regression Analysis for OCT Parameters Correlated With BCVA (logMAR)
|Foveal Width||Foveal Depression||Foveal Thickness||Thickness of Inner Retina||Thickness of Outer Retina|