Serial evaluation of retinal vascular changes in infants treated with intravitreal bevacizumab for aggressive posterior retinopathy of prematurity in zone I

Clinical profile and management outcomes of posterior zone 1 retinopathy of prematurity

BACKGROUND

To analyse the varied clinical profile and treatment outcomes of posterior zone 1 retinopathy of prematurity (ROP).

METHODS

This retrospective case-series included 54 eyes of 27 infants of posterior zone 1 ROP treated at our centre from January 2018 to June 2019. Three clinical patterns were observed at presentation - Posterior zone 1 ROP without detachment (group 1), with subtotal detachment (group 2) and total detachment (group 3) of the vascularised retina. Their profile, treatment options and outcomes were studied.

RESULTS

The mean birth weight was 1204 ± 262 gm and mean gestational age was 28.8 ± 2 weeks. Clinical presentation as per group 1, 2 and 3 was seen in 33/54 (61.1%), 9/54 (16.6%) and 12/54 (22.2%) eyes, respectively. All the eyes received intravitreal ranibizumab as primary intervention. In group 1, 25/33 (75.7%) eyes had laser and 8/33 (24.2%) had surgery whereas, in group 2, 2/9 (22.2%) eyes had laser and 7/9 (77.7%) underwent surgery as a second intervention. In group 3, only 3 /12 (25%) eyes had second intervention (surgery). Surgical outcomes of group 1 and 2 were better than group 3. At last follow-up, macular vascularisation was noted in 33/54 (61.1%) eyes.

CONCLUSION

A customised and multifaceted treatment approach is required to treat posterior zone 1 ROP.

Combined intravitreal ranibizumab and zone I sparing laser ablation in infants with posterior zone I retinopathy of prematurity

Purpose

To evaluate the efficacy of combined intravitreal ranibizumab (IVR) and zone I sparing laser ablation in infants with posterior zone I Retinopathy of Prematurity (ROP).

Methods

This was a retrospective, interventional case series including premature infants diagnosed with posterior zone I ROP (n = 24) on ROP screening. Charts and RetCam images of preterm infants with posterior zone I ROP treated with immediate IVR and zone I sparing laser ablation at 4 weeks between April 2016 and September 2019 were reviewed. Data were analyzed and tabulated using frequency and descriptive statistics to describe the demography, morphology, and treatment outcomes. Primary outcome measure was structural outcome at 6 months. It was further categorized as favorable and unfavorable.

Results

Twenty-four infants (48 eyes) with a mean gestational age of 28.54 ± 1.98 weeks and birth weight of 1180.33 ± 280.65 grams were analyzed. Thirty-six (75%) eyes had persistent tunica vasculosa lentis and twenty-six (54.1%) eyes had iris neovascularization. All eyes had features of aggressive posterior retinopathy of prematurity (APROP) limited to posterior zone I. The mean duration between IVR and zone I sparing laser ablation was 29.62 ± 6.36 (range: 24-34) days. One infant (2 eyes) received a second IVR treatment for recurrence of plus disease and persistent new vessels close to the fovea. Laser augmentation was done in 13 (27.1%) eyes. A favorable structural outcome was seen in 45 (93.7%) eyes.

Conclusion

Posterior zone I ROP presents as APROP. Combined IVR and zone I sparing laser ablation appears effective treatment option in these eyes.

Anti-vascular endothelial growth factor in the management of retinopathy of prematurity: A survey among the members of Indian Retinopathy of Prematurity Society

Purpose:

To report the results of the survey for the role of anti-VEGF in the management of retinopathy of prematurity (ROP) among the members of Indian ROP (iROP) society.

Methods:

A questionnaire was designed in English using Google forms and its link was circulated to the members of the iROP society on their mobile numbers. The survey included questions pertaining to demographics, anti-VEGF agents, injection technique, post-injection follow-up, and documentation pertaining to their ROP practice. Anonymous responses were obtained and analyzed for individual questions.

Results:

226 members of the society were contacted and 157 responded (69.4%) to the survey. 137 (87.2%) respondents used anti-VEGF in the management of ROP. Aggressive posterior ROP (APROP) was the most common indication (78, 52.7%). The procedure was carried out in the main operation room (102, 70.3%) simultaneously for both the eyes (97; 68%) under topical anesthesia (134; 86.4%) by most of the respondents. One-hundred thirteen (77.9%) respondents used half of the adult dose, irrespective of the agent used; however, more than half of them preferred bevacizumab (85, 54%). 53 (36.3%) respondents followed up infants as per disease severity rather than a fixed schedule while only 33 (23%) performed photo documentation. 151 (96.2%) respondents felt the need for guidelines regarding the usage of anti-VEGF in ROP.

Conclusion:

There is an increase in the trend towards the use of anti-VEGF in the management of severe ROP, particularly APROP. However, there are considerable variations among the ROP practitioners regarding the agent, dosage, follow-up schedule, and documentation, suggesting the need for uniform guidelines.

Aggressive posterior retinopathy of prematurity: a review on current understanding

A review of literature was performed, focused on the etiopathogenesis of aggressive posterior retinopathy of prematurity (APROP), the characteristic and atypical clinical features, management strategies, anatomical and visual outcomes. Characteristically APROP has zone I/posterior zone II involvement with prominent plus disease, featureless junction, large vascular loops, flat extra-retinal fibrovascular proliferation, and a rapidly progressive course. The risk factors for APROP are extreme prematurity (birth weight ≤1000 gram and/or gestational age ≤28 weeks), dysregulated oxygen supplementation, intrauterine growth retardation, sepsis, and thrombocytopenia. The uncommon presentations include small zone I disease, a hybrid disease with additional ridge tissue, and APROP in bigger babies with birth weight greater than 1500 g. Laser photocoagulation role is limited by the resultant visual field loss and high refractive error. Although anti-vascular endothelial growth factor injection allows peripheral retinal vascularization; reactivation of disease, systemic absorption of the drug and long-term safety are the chief concerns. Early vitrectomy is required when tractional retinal detachment develops. The visual outcome depends upon the morphology and vascular development of the macula. With the limited yet emerging new understanding of the pathophysiology, a multifaceted rational and individualized treatment strategy is suggested for APROP. Best practices in neonatal intensive care may prevent the occurrence of APROP. Further studies need to be performed for the prevention and safe, effective management of APROP.

Characteristics of 'sawtooth shunt' following anti-vascular endothelial growth factor for aggressive posterior retinopathy of prematurity

OBJECTIVE

To explore the characteristics of 'sawtooth shunts (STS)' following intravitreal anti-vascular endothelial growth factors (anti-VEGF) for aggressive posterior retinopathy of prematurity (AP-ROP).

DESIGN

Prospective observational study.

METHODS

In a prospective observational study, 45 eyes of 24 babies receiving intravitreal anti-VEGF for AP-ROP or hybrid ROP were analyzed. Anti-VEGF molecule and doses: bevacizumab (0.62 mg or ½ IVB, n = 30 eyes; 0.25 mg or 1/5IVB, n = 9 eyes; 0.12 mg or 1/10 IVB, n = 1 eye); or ranibizumab (0.25 mg or ½IVR, n = 3 eyes; 0.1 mg or 1/5IVR, n = 2 eyes). They were followed every 1-2 week till disease regression with or without laser treatment. Development of STS, its variants, characteristics, timeline, and final outcomes was analyzed.

RESULTS

STS occurred in 26 (57.7%) eyes at 1-6 weeks following anti-VEGF injections and persisted for 1-14 weeks. While the shunt regressed spontaneously in half of the treated eyes (n = 13) with anti-VEGF alone, the other half (n = 13) required additional laser because of either non-compliance (n = 9) or recurrence (n = 4).

CONCLUSION

The STS was observed to be an important retinal vascular change seen in infants treated with intravitreal anti-VEGF at half adult doses. It warrants further studies to explore the association between STS and its association with disease recurrence or regression.

Revascularization after angiogenesis inhibition favors new sprouting over abandoned vessel reuse

Inhibiting pathologic angiogenesis can halt disease progression, but such inhibition may offer only a temporary benefit, followed by tissue revascularization after treatment stoppage. This revascularization, however, occurs by largely unknown phenotypic changes in pathologic vessels. To investigate the dynamics of vessel reconfiguration during revascularization, we developed a model of reversible murine corneal angiogenesis permitting longitudinal examination of the same vasculature. Following 30 days of angiogenesis inhibition, two types of vascular structure were evident: partially regressed persistent vessels that were degenerate and barely functional, and fully regressed, non-functional empty basement membrane sleeves (ebms). While persistent vessels maintained a limited flow and retained collagen IV+ basement membrane, CD31+ endothelial cells (EC), and α-SMA+ pericytes, ebms were acellular and expressed only collagen IV. Upon terminating angiogenesis inhibition, transmission electron microscopy and live imaging revealed that revascularization ensued by a rapid reversal of EC degeneracy in persistent vessels, facilitating their phenotypic normalization, vasodilation, increased flow, and subsequent new angiogenic sprouting. Conversely, ebms were irreversibly sealed from the circulation by excess collagen IV deposition that inhibited EC migration and prevented their reuse. Fully and partially regressed vessels therefore have opposing roles during revascularization, where fully regressed vessels inhibit new sprouting while partially regressed persistent vessels rapidly reactivate and serve as the source of continued pathologic angiogenesis.

Efficacy of intravitreal aflibercept monotherapy in retinopathy of prematurity evaluated by periodic fluorescence angiography and optical coherence tomography

PURPOSE

To evaluate the efficacy of intravitreal aflibercept (IVA) in vascular and macular maturation in neonates with type 1 retinopathy of prematurity (ROP) and aggressive posterior retinopathy of prematurity (APROP).

MATERIALS AND METHODS

Thirty-six eyes of 18 patients with type 1 ROP or APROP in zone I or posterior zone II were enrolled in our study. At baseline, only fluorescein angiography (FA) was performed. After IVA injection, both FA and optical coherence tomography (OCT) were performed after 6.8 ± 0.8 (range 6-8) and 19 ± 0.9 (range 18-20) weeks to follow vascular and macular changes.

RESULTS

Both diffuse flat neovascularization with leakage and abnormal vascular branching at the small arteriolar level were detected in all eyes (100%) at baseline FA. Regression of the disease was observed in 34 eyes (94.4%) in the first week with binocular indirect ophthalmoscopy. Early unresponsiveness in remaining two eyes of an infant required an IVA re-treatment. Late reactivation was detected only in 19.4% of eyes, none of which required treatment during 12 months of follow-up. The most common feature after IVA injection was abnormal branching at capillary level, which was noted in 100% in the first post-injection FA and 50.0% of all eyes in the second FA. Meanwhile, the end limit of vascularization was observed in zone III in 83.3% of eyes. No vascular abnormality was also detected in 27.3% of eyes. The OCT examination at a mean postmenstrual age of 43.4 weeks revealed cystoid macular changes in four eyes of two infants (11.1%), normal foveal contour in 30 eyes of 15 infants (83.3%) and matured ellipsoid zone at the foveal center in 28 eyes of 14 infants (77.8%). Macular maturation was complete in all eyes in the last OCT analyses.

CONCLUSION

Intravitreal aflibercept monotherapy has been an effective treatment in type I ROP and APROP with much lower early and late re-treatment rates because of early unresponsiveness and late reactivation, respectively. In most of the eyes, rapid vascular outgrowth beyond zone III together with normal macular maturation was observed more precisely by periodic FA and OCT.

Role of cytokines and treatment algorithms in retinopathy of prematurity

PURPOSE OF REVIEW

Currently, severe retinopathy of prematurity (ROP) is diagnosed by clinical evaluation and not a laboratory test. Laser is still considered standard care. However, anti-vascular endothelial growth factor (VEGF) agents are being used and there are questions whether and/or if to use them, what dose or type of agent should be considered and what agent may be most beneficial in specific cases. Also unclear are the effects of laser or anti-VEGF on severe ROP, refractive outcomes or infant development. This article reviews recent studies related to these questions and other trials for severe ROP.

RECENT FINDINGS

Imaging studies identify biomarkers of risk (plus disease, stage 3 ROP, and ROP in zone I). Intravitreal bevacizumab or ranibizumab are reported effective in treating aggressive posterior ROP in small series. Recurrences and effects on myopia vary among studies. Use of anti-VEGF agents affects cytokines in the infant blood and reduces systemic VEGF for up to 2 months, raising potential safety concerns. The effects of treatment vary based on infant size and are not comparable. Evidence for most studies is not high.

SUMMARY

Studies support experimental evidence that inhibiting VEGF reduces stage 3 ROP and peripheral avascular retina. Ongoing large-scale clinical trials may provide clarity for best treatments of severe ROP. Current guidelines hold for screening and treatment for type 1 ROP.

Antivascular endothelial growth factor in the treatment of retinopathy of prematurity

PURPOSE OF REVIEW

To review the most recent literature regarding the clinical experience of antivascular endothelial growth factor (anti-VEGF) therapies in the treatment of retinopathy of prematurity (ROP).

RECENT FINDINGS

Anti-VEGF agents in stage 3+ and aggressive posterior ROP have been shown to induce rapid ROP regression. However, significant reoccurrence rates can require repeat injections and thus longer term and more frequent follow-up. Initial studies reflect conflicting evidence regarding significant systemic side effects of these treatments, and outcomes in these patients past the first few years of life are yet to be definitively determined.

SUMMARY

Although anti-VEGF therapies show promise in the treatment of ROP, frequent reoccurrences and lack of thorough data about long-term side effects of pharmacologic intervention necessitate further research before anti-VEGF agents become the mainstay of ROP management.