Laser treatment for retinopathy of prematurity

Comparison of different agents and doses of anti-vascular endothelial growth factors (aflibercept, bevacizumab, conbercept, ranibizumab) versus laser for retinopathy of prematurity: A network meta-analysis

Laser photocoagulation (LPC) and/or intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections constitute the current standard treatment for retinopathy of prematurity (ROP). This network meta-analysis focus on whether a ranking of interventions may be established for different dose levels of intravitreal injection of anti-VEGF agents (aflibercept, bevacizumab, conbercept, ranibizumab) as primary treatments for ROP versus laser in terms of retreatment rate as primary outcome, and time to retreatment and refractive error as secondary endpoints, since best anti-VEGF dosage remains under debate. Sixty-eight studies (15 randomized control trials and 53 nonrandomized studies) of 12,356 eyes of 6445 infants were retrieved from databases (2005 Jan. - 2023 June). Studies were evaluated for model fit, risk of bias and confidence of evidence in Network Meta-Analysis (CINeMA). Bayesian NMA showed that anti-VEGF drugs were not inferior to laser in terms of retreatment rate. For intravitreal bevacizumab (IVB), doses half of the conventional infant dose showed a low risk of retreatment rate (risk ratio (RR) of 1.43; 95% credible interval (CrI): 0.508, 4.03). On probability ranking as surface under the cumulative ranking curve (SUCRA) plot, half dose of bevacizumab had a better position than conventional and augmented (1.2-2 times the regular dose) doses. A similar probability trend was observed for half vs. conventional doses of aflibercept and ranibizumab. Conventional infant dose of conbercept showed the lowest risk for retreatment (RR 0.846; 95% CrI: 0.245, 2.91). For secondary endpoints, lower doses of anti-VEGF agents were associated with shorter times to retreatment. The largest changes were noted for the augmented doses of bevacizumab and ranibizumab (0.3 mg) with means of 14.1 weeks (95% CrI: 6.65, 21.6) and 12.8 weeks (95% CrI: 3.19, 20.9), respectively. Finally, NMA demonstrated better refractive profile for anti-VEGF than laser therapy, especially for the conventional infant doses of bevacizumab and ranibizumab which exhibited a significantly better refractive profile than LPC, with mean differences of 1.67 (spherical equivalent - diopters) (95% CrI: 0.705, 2.67) and 2.19 (95% CrI: 0.782, 3.59), respectively. In the SUCRA plots, LPC had a markedly different position with a higher probability for myopia. Further clinical trials comparing different intravitreal doses of anti-VEGF agents are needed, but our findings suggest that low doses of these drugs retain efficacy and may reduce ocular and systemic undesired events.

Non-surgical treatment of stage 4A retinopathy of prematurity

BACKGROUND

Retinopathy of prematurity (ROP) is a major cause of visual impairment in premature infants, often requiring surgical interventions in advanced stages. This retrospective case series study investigates non-surgical management for Stage 4A ROP, specifically the use of combined laser therapy and intravitreal anti-vascular endothelial growth factor (VEGF) injections.

METHODS

Ten eyes from five infants with Stage 4A ROP were treated with a combined laser and anti-VEGF approach. Comprehensive follow-up examinations were conducted to evaluate the treatment outcomes.

RESULTS

The study demonstrated successful retinal attachment without complications, showcasing the efficacy and safety of this non-surgical method. A comparison with surgical interventions highlighted the potential benefits in terms of reduced adverse effects.

DISCUSSION

This combined treatment emerges as a promising first-choice option for Stage 4A ROP, offering rapid regression without surgical intervention, particularly in early stages. However, larger randomized clinical trials are necessary to validate these findings and establish definitive guidelines for managing this complex condition.

CONCLUSION

Combined laser and anti-VEGF therapy proved to be an effective and safe non-surgical approach for Stage 4A ROP, with the potential to reduce the need for surgery, especially in its early presentation. Further research is required to confirm these findings and provide comprehensive recommendations for clinical practice.

INCIDENCE AND RISK FACTORS FOR EXUDATIVE RETINAL DETACHMENT FOLLOWING LASER PHOTOCOAGULATION FOR RETINOPATHY OF PREMATURITY

PURPOSE

Exudative retinal detachment (ERD) may result from laser photocoagulation for retinopathy of prematurity. Although risk factors have been hypothesized from case reports, comparative studies have not been reported. We sought to evaluate risk factors for ERD following laser, comparing affected and unaffected infants.

METHODS

Retrospective cohort study of infants undergoing retinopathy of prematurity laser at the Children's Hospital of Philadelphia over 6 years. All received near-confluent laser of avascular retina. Demographic, medical, and procedural risk factors for ERD were evaluated in univariate analysis because of the rarity of ERD.

RESULTS

Among 149 lasered infants, 6 infants (4%, 95% confidence interval [CI] 1.5%-8.6%) developed ERD. Race was a significant risk factor ( P = 0.01). Among 71 African American or Hispanic infants, 6 (8.5%, 95% CI 3.2%-17.5%) developed ERD. Among 78 non-African American or Hispanic infants, 0 (0%, 95% CI 0%-4.6%) developed ERD. There were no significant differences in the other studied factors.

CONCLUSION

Exudative retinal detachment was uncommon (4%) following retinopathy of prematurity laser. Despite so few cases, darker pigmented race with likely increased pigmented fundi was significantly associated with an increased ERD risk. Further study may reveal whether increased choroidal pigment causes greater laser tissue damage or makes it difficult to discern the ora, resulting in inadvertent lasering of the ciliary body, leading to ERD.

The efficacy and ocular safety following aflibercept, conbercept, ranibizumab, bevacizumab, and laser for retinopathy of prematurity: a systematic review and meta-analysis

BACKGROUND

Retinopathy of prematurity (ROP) is typically treated with laser photocoagulation and/or intravitreal anti-vascular endothelial growth factor (anti-VEGF). To the best of our knowledge, most systematic reviews have focused on comparing anti-VEGF against laser treatment while comparisons between different anti-VEGF agents are lacking. Thus, we conducted this meta-analysis to compare the efficacy and safety of different anti-VEGF agents or laser after primary ROP therapy.

METHODS

We conducted a comprehensive search across multiple databases up to November 2022. We included studies that used anti-VEGF or laser for ROP with comparable cohorts.

RESULTS

Overall, 44 studies were included in this meta-analysis. When comparing anti-VGEF with laser, we found that the anti-VEGF group had a significantly higher retreatment rate (RR = 1.56, 95%CI = [1.06, 2.31], p = 0.03), a longer time from treatment to retreatment (WMD = 5.99 weeks, 95%CI = [4.03, 7.95], p < 0.001), a lower retinal detachment rate (RR = 0.55, 95%CI = [0.30, 0.91], p = 0.02), higher spherical equivalent (WMD = 1.69D, 95%CI = [0.61, 2.77], p = 0.002), lower myopia rate (RR = 0.69, 95%CI = [0.50, 0.97], p = 0.03) and lower anisometropia rate (RR = 0.44, 95%CI = [0.29, 0.67], p = 0.0001). In comparisons between ranibizumab and bevacizumab, the intravitreal ranibizumab (IVR) group was associated with higher recurrence rate (RR = 2.02, 95%CI = [1.49, 2.73], p < 0.0001), higher retreatment rate (RR = 1.70, 95%CI = [1.17, 2.47], p = 0.0006), and lower high myopia rate (RR = 0.31, 95%CI = [0.12, 0.77], p = 0.01). Similarly, when compared to aflibercept and conbercept, the IVR cohort also demonstrated higher recurrence and retreatment rates. While no significant differences were observed in any of the variables included in the statistical analysis in the comparison between bevacizumab and aflibercept.

CONCLUSIONS

Anti-VEGF was associated with higher retreatment and lesser incidence of myopia as compared to laser. Laser therapy was linked to more complications like retinal detachment and myopia. Ranibizumab exhibited higher recurrence and retreatment rates compared to bevacizumab, aflibercept, and conbercept.

Twelve-year outcomes of bedside laser photocoagulation for severe retinopathy of prematurity

Purpose

The purpose of this study is to evaluate the 12-year outcomes of bedside laser photocoagulation (LP) for severe retinopathy of prematurity (ROP) under sedation combined with ocular surface anesthesia in neonatal intensive care units (NICU).

Design

The study is a retrospective case series.

Methods

Infants treated with bedside LP for severe ROP from April 2009 to September 2021 were included. All LP treatments were performed under sedation and surface anesthesia at the bedside in NICU. Data were recorded for clinical and demographic characteristics, total laser spots, duration of treatment, proportion of total regression of ROP, proportion of recurrence, and adverse events.

Results

A total of 364 infants (715 eyes) were included, with a mean gestational age of 28.6 ± 2.4 weeks (range: 22.6-36.6 weeks) and a mean birth weight of 1,156.0 ± 339.0 g (range: 480-2,200 g). The mean number of laser spots was 832 ± 469, and the mean duration of treatment was 23.5 ± 5.3 min per eye. Of all the eyes, 98.3% responded to LP with complete regression of ROP. ROP recurred in 15 (2.1%) eyes after the initial LP. Additional LP was performed in seven (1.0%) eyes. No patient exhibited mistaken LP of other ocular tissues, and there were no serious ocular adverse effects. None of them needed endotracheal intubation.

Conclusions

Bedside LP treatment is effective and safe for premature infants with severe ROP under sedation and surface anesthesia in NICU, especially for infants whose general condition is unstable and not suitable for transport.

Outcomes of near confluent laser versus combined less dense laser and bevacizumab treatment of prethreshold ROP Type 1 Zone 2: a randomized controlled trial

BACKGROUND

To evaluate the results of near confluent laser therapy versus combined less dense laser and intra vitreal bevacizumab in treatment of infants with type 1 retinopathy of prematurity (ROP) in zone II.

METHODS

This is a prospective double-blinded randomized clinical trial study. Infants with Type 1 ROP in Zone 2 were randomized into case and control groups. Conventional laser therapy was executed for control group and combination of IVB and laser treatment was employed for the case group.

RESULTS

Eighty-six eyes from 43 infants were analyzed in this trial. The first group included 42 eyes from 21 infants receiving a combination of laser ablation and IVB. The second group contained 44 eyes from 22 infants who received only conventional laser therapy. The combined IVB and laser ablation group demonstrated the neovascularization regression (20 out of 21 infants) one week after the procedure. In the conventional laser therapy group, this regression was found in (12 out of 22 infants) within one week after laser therapy (P = 0.001). Plus disease regression was observed in 20 (20/21) of combined treatment group and 7 infants (7/22) of conventional laser treatment group after one week.

CONCLUSION

Combined less dense laser and bevacizumab treatment resulted in more rapid regression in comparison with the conventional laser treatment.

TRIAL REGISTRATION

IRCT20201120049450N1, 27/12/2021.

Development of myopia in laser-treated ROP infants: prematurity or laser photocoagulation?

PURPOSE

To investigate the relationship between the development of corrected 1-year-old refraction values and risk factors in preterm infants who underwent laser photocoagulation (LPC) therapy for retinopathy of prematurity (ROP).

METHODS

The ophthalmic examination findings of preterm neonates who had developed Type I ROP and received LPC therapy were evaluated retrospectively. The association between spherical equivalent (SE) values and clinical findings were analyzed by using multivariable linear regression analysis.

RESULTS

The study included 157 eyes of 80 neonates with a mean birth week of 27.1 ± 2.2 weeks (23 to 32 weeks) and a mean birth weight of 995 ± 273 g (565 to 1760 g). The treatments were administered on an average of 36.8 ± 2.7 (32 to 45 weeks) postmenstrual age. LPC treatment was applied bilaterally to 77 of the 80 neonates included in the study, and unilaterally to 3 of them. The mean ± standard deviation of the SE value was 0.31 ± 1.89 diopters (D) (- 8.00 to 4.63 D) according to the results of the 1-year corrected age refraction examination. In univariate analysis, no significant association between GA, BW, and ROP zone and SE value, while the number of laser spots (ß =  - 0.27 ± 0.00 D, p = 0.00) and stage 3 ROP (ß =  - 0.29 ± 0.37 D, p = 0.00) were significantly associated with the SE value. In multivariable linear regression analysis, a significant association between number of laser spot, stage 3 ROP and SE value (ß =  - 0.25 ± 0.00 D, p = 0.01 for number of laser spot, ß =  - 0.28 ± 0.36 D, p = 0.00 for stage 3 ROP).

CONCLUSION

In conclusion, this study supports that stage of ROP and the number of laser spots count applied in photocoagulation treatment for ROP is significantly correlated with degree of myopia (p < 0.05).

Exploration of Hub Genes in Retinopathy of Prematurity Based on Bioinformatics Analysis of the Oxygen-Induced Retinopathy Model

Retinopathy of prematurity (ROP) is a major blindness-causing disease that is characterized by an arrest of normal vascular development and neovascularization of the retina. Previous studies have shown that genetic factors may be associated with the development and severity of ROP. However, the genes and mechanisms underlying ROP remain unclear. We aimed to identify hub genes in ROP and drugs related to these genes by integrative analysis. The expression profiles of GSE158799 and GSE135844 were acquired from the Gene Expression Omnibus (GEO) database, and differentially expressed genes (DEGs) were identified. Then, an integrative analysis was performed including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), gene set enrichment analysis (GSEA), protein-protein interaction (PPI) network, transcription factor (TF)-gene, and miRNA-gene networks analysis. Moreover, we verified hub genes and identified potential drugs. 225 common DEGs were identified. Biological function analysis indicated that angiogenesis, cell surface, cell adhesion, extracellular matrix, and focal adhesion genes were enriched among DEGs. The PI3K/Akt signalingpathway, focal adhesion, and extracellular matrix (ECM)-receptor interaction were markedly enriched in the KEGG pathway analysis. Finally, 5 hub genes related to the nosogenesis of ROP were identified and found to be targeted by VEGFA inhibitors, TLR4 antagonists, and sunitinib. The present study showed that VEGFA, ACTA2, MKI67, CD68, and TLR4 are potential hub genes involved in the pathogenesis of ROP. Moreover, TLR4 antagonists and sunitinib may be new candidate drugs for ROP therapy, in addition to VEGFA inhibitors.

Exudative Retinal Detachment After ROP Laser Photocoagulation

Exudative retinal detachment (ERD) can be a rare postoperative complication of laser photocoagulation surgery when used to treat type I retinopathy of prematurity (ROP). We present a case of bilateral ERD following ROP laser photocoagulation. A preterm male infant born at 24 weeks gestation and weighing 600 grams was diagnosed with stage 3/zone II/pre-plus ROP in both eyes. He was on oxygen therapy for 92 days due to chronic lung disease and was treated with laser photocoagulation at 40 weeks postmenstrual age. Initial laser settings (in use for over 15 years) were 300 mW power, 300 ms duration, and 300 ms intervals. Due to strong laser absorption, power was decreased to 250 mW for most of the procedure. He was prescribed prednisolone acetate drops four times per day for postoperative care. One week later, he developed complete ERD in both eyes. The patient was monitored in the neonatal intensive care unit (NICU) for three weeks and prednisolone acetate drops were increased to every two hours and tapered over one month. Complete resolution of ERD with residual peripheral exudate bilaterally was observed eight weeks after surgery.

This case suggests that even after the settings of an ROP laser have been used safely for 15 years, it is important to tailor settings for each individual patient utilizing the least power and duration for laser application as possible. Furthermore, this case highlights the importance of titrating laser power in response to spot blanching throughout the procedure. However, near-complete resolution of post-ROP laser ERD is possible with minimal changes to standard postoperative management.

Risk factors for early-onset high myopia after treatment for retinopathy of prematurity

PURPOSE

To investigate the prevalence of myopia and high myopia and the risk factors for high myopia in infants at 3 years of age with retinopathy of prematurity (ROP).

STUDY DESIGN

Retrospective, observational.

METHODS

We retrospectively analyzed all 89 preterm infants (178 eyes) with medical records of ROP between October 2008 and March 2018 at Toho University Medical Center Omori Hospital; these infants had a birth weight of less than 1,500 g and were followed up at least until 3 years of age. Cycloplegic autorefraction was performed to measure refractive outcomes. Multivariate analysis was performed to determine the risk factors for early-onset high myopia at 3 years of age.

RESULTS

The prevalence of myopia and high myopia was significantly higher in the treated group (59.7% and 17.9%, respectively) than in the untreated group (19.7% and 0%, respectively) (p<0.001). Spherical equivalent (SE) at age 3 was more myopic in the treatment group (-1.72 ± 3.53 D) than in the untreated group (0.54 ± 1.08 D) (p<0.001). In the sub-analysis of the treatment group, there was a significant correlation between SE at age 3 and the number of laser shots (R² = 0.36, p<0.001). Multivariate logistic analysis showed that the number of laser shots was an independent risk factor for early onset high myopia (p<0.05).

CONCLUSION

The number of laser shots is an independent risk factor for early onset high myopia, and preterm infants who have undergone laser treatment for severe ROP should be considered for early optical correction with cycloplegic refractive examination.

Morphology and Vessel Density of the Macula in Preterm Children Using Optical Coherence Tomography Angiography

Background: Retinal morphology changes may be associated with prematurity and can lead to visual impairment. Optical coherence tomography angiography may contribute to understanding the pathomechanism of structural and vascular retinal impairment in premature children. The aim of this study was to assess an influence of prematurity, neonatal clinical characteristics, and a history of retinopathy of prematurity (ROP) on the morphology and retinal vascularity of macula in children. Methods: A case−control study of 123 preterm children and 86 full-term children was performed. The age of the subjects was 10.45 years (IQR: 8.12−12.77), while the age of the control group was 11.78 years (IQR: 8.81−13.79). Optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA, angio-OCT) were performed using RTVueXR Avanti (Optovue, Fremont, CA, USA). Ganglion cell complex (GCC), foveal thickness (FT), parafoveal thickness (PFT), size of foveal avascular zone (FAZ) in superficial plexus, superficial capillary vessel density (sVD), deep capillary vessel density (dVD), central choroidal thickness (CCT), and presence of macular hypoplasia were analyzed. The association between OCT/angio-OCT results and clinical characteristics including the degree of ROP and therapy requirements was assessed in preterm infants. Results: Foveal morphology was affected in preterm children with high incidence of foveal hypoplasia (24.77%). GCC was thinner in preterm children compared to controls: avgGG 93 μm vs. 100 μm, p < 0.001. No associations between GCC and gestational age (R = −0.085; p = 0.228) and birth weight (R = −0.054; p = 0.446) were found. FAZ in preterm group was smaller than in controls (0.13 ± 0.09 vs. 0.22 ± 0.09; p < 0.001). FAZ area correlated with gestational age (R = 0.456; p < 0.001) and birth weight (R = 0.472; p < 0.001). Deep vessel density in the fovea was higher in preterm children than in control group (p < 0.001). PFT was significantly lower in preterm children compared to control group. However, increased thickness in the fovea was noted in preterm children (p < 0.001). FT was inversely correlated with gestational age (R = −0.562; p < 0.001) and birth weight (R = −0.508, p < 0.001). CCT was lower in preterm children (312 μm vs. 337.5 μm, p < 0.001) Parameters of GCC and FT were higher in patients with ROP required treatment compared to patients without ROP and spontaneously regressed retinopathy. FAZ was smaller in patients with retinopathy than in preterm children without ROP. Conclusion: Prematurity has a significant negative impact on GCC, macular morphology, and vascularization. In premature children, decreased FAZ, increased FT, and vessel density were strongly associated with gestational age, birth weight, Apgar score, ROP stage, and treatment requirement. Optical coherence tomography angiography is a useful tool for detecting retinal changes in premature children.

New trends in intravitreal anti-VEGF therapy for ROP

Retinopathy of Prematurity (ROP) affects premature newborns, and it can cause childhood blindness and visual impairment if untreated. The understanding of the pathogenetic role of Vascular Endothelial Growth Factor (VEGF) has led to development of therapeutic strategies such as intravitreal anti-VEGF drugs. We reported drug efficacy and ROP recurrence rates, extrapolated from the reviewed studies. Association of Pegabtanib and laser photocoagulation confers efficacy in the regression of ROP stage 3 plus in zone I / II in 89.7% of treated eyes, reducing the recurrence rate to 14.6% compared to 50% of laser therapy alone. Irrespective of the dose, Ranibizumab demonstrated average efficacy greater than 75% on regression of active disease with the highest rates of the dose of 0.1 mg (92.5%). The recurrence, on the other hand, is the highest among this new anti-VEGF agents and is around an average of 41.5%, which records the highest values in the case of Aggressive Posterior Rop (APROP). Aflibercept at a dose of 1 mg demonstrated average efficacy of about 81.9% of treated infants, analyzing significantly fewer studies than Ranibizumab. The recurrence rate stands at an average of 28.9%, especially in the later forms of ROP. Using a dose of 0.25 mg of Conbercept, the disease regression rate is currently on average 83%, with an average recurrence rate of 15.24%, the peak of which was observed in cases of ROP in zone I. Further studies are needed to prove safety at long term, because,at the moment, only short-term data are available.

Transscleral vs transpupillary diode laser photocoagulation for the treatment of zone II type 1 retinopathy of prematurity: Anatomical and refractive outcomes

Purpose

To compare the anatomical and refractive outcomes of transscleral diode versus transpupillary laser photocoagulation for the treatment of zone II type 1 retinopathy of prematurity (ROP).

Methods

In this prospective comparative interventional case series, infants with type 1 ROP in zone II were assigned to either transpupillary or transscleral laser based on the surgeons' expertise area. The rate of regression, need for retreatment, and structural and biometric outcomes at month 6 were evaluated and compared between the two treatment groups.

Results

In total, 209 eyes were enrolled; 145 eyes of 77 infants and 64 eyes of 33 infants and were in transscleral and transpupillary groups, respectively. There was no significant difference in baseline characteristics between the groups. There was no significant difference in retreatment rates (1.6% vs. 3.4%; P = 0.669) and progression to stage 4 (1.6% vs. 2.8%; P = 0.999) between the transpupillary and transscleral groups, respectively. At month 6, the mean spherical equivalent was 0.31 ± 3.57 and 0.44 ± 2.85 diopters, and the axial length was 18.28 ± 6.22 and 18.36 ± 6.87 mm in the transpupillary and transscleral groups, respectively, without a significant difference between groups. There was no significant difference in the rate of myopia (43.8% vs. 33.8%; P = 0.169) and high myopia (4.7% vs. 4.8%; P = 0.965) in transpupillary and transscleral groups at month 6.

Conclusion

The transpupillary and transscleral laser photocoagulation routes are both effective in the treatment of zone II type 1 ROP and show no significant differences in anatomical or refractive outcomes in relation to the route chosen.

7, 8-Dihydroxyflavone, a TrkB receptor agonist, provides minimal protection against retinal vascular damage during oxygen-induced ischemic retinopathy

Retinopathy of prematurity (ROP) is one of the main causes of blindness in children worldwide. Brain-derived neurotrophic factor (BDNF) and its receptor, tropomyosin-related kinase B (TrkB), play critical protective roles in the development and function of neurons and vasculature. Lack of BDNF expression results in increased endothelial cell apoptosis and reduced endothelial cell-cell contact. Premature babies who develop ROP tend to have lower serum BDNF levels. BDNF expression is also significantly lower in mouse retinas following exposure to hyperoxia compared to those reared in room air. Specifically, BDNF promotes angiogenic tube formation of endothelial cells (EC), and it is considered an EC survival factor required for stabilization of intramyocardial vessels. We hypothesized that the activation of TrkB receptor protects retinal vasculature in the mice during oxygen-induced ischemic retinopathy (OIR), a model of ROP. To test this hypothesis, we treated neonatal mice with 7,8-dihydroxyflavone (DHF) (5 mg/kg body weight), a TrkB receptor agonist. We examined its potential protective effects on retinal vessel obliteration and neovascularization, two hallmarks of ROP and OIR. We found that retinas from DHF treated postnatal day 8 (P8) and P12 mice have similar levels of vessel obliteration as retinas from age-matched control mice subjected to OIR. Similarly, DHF showed no significant effect on mitigation of retinal neovascularization during OIR in P17 mice. Collectively, our studies demonstrate that the TrkB receptor agonist DHF provides no significant protective effects during OIR.

Complications of retinopathy of prematurity treatment

PURPOSE OF REVIEW

The purpose of this review is to summarize complications of treatment for retinopathy of prematurity (ROP) and to compare complications of laser and intravitreal antivascular endothelial growth factor (VEGF) injections.

RECENT FINDINGS

Poor structural outcomes and myopia are more common with laser for severe ROP than with anti-VEGF. Clinical trial data show unfavourable outcomes in 9.1-9.5% of laser treated, and 1.4-3.6% of anti-VEGF treated eyes. Additional randomized trial data show risk for very high myopia (≥-8.00D) to be 3.8 and 51.4% for zone I eyes treated with bevacizumab and laser, respectively. However, anti-VEGF may be complicated by late recurrence and is more likely to require retreatment than laser. Laser often necessitates general anaesthesia with its attendant risks, including worse short-term respiratory outcomes. Neurodevelopmental complications have been reported with anti-VEGF, but existing studies are subject to bias.

SUMMARY

Treatment complications are substantially different for the two modalities in common use today. In more severe cases, risk of poor structural outcome and myopia favour treatment with anti-VEGF. In less severe ROP, risk of recurrence and the need for additional treatments may favour laser. Additional data are needed to establish comparative risks of neurodevelopmental complications.

Study protocol for a multicentre, open-label, single-arm phase I/II trial to evaluate the safety and efficacy of ripasudil 0.4% eye drops for retinopathy of prematurity

INTRODUCTION

Retinopathy of prematurity (ROP) is a vascular proliferative disorder that occurs in preterm infants. Existing treatments are only indicated in severe ROP cases due to the high invasiveness and the potential risk of irreversible side effects. We previously elucidated that ripasudil, a selective inhibitor of the Rho-associated protein kinase, has the ability to inhibit abnormal retinal neovascularisation in animal models. In addition, ripasudil eye drops (Glanatec ophthalmic solution 0.4%) have been already used for the treatment of glaucoma. Since eye drop therapy is less invasive, early intervention for ROP is possible. The purpose of this phase I/II trial is to evaluate the safety and efficacy of ripasudil eye drops for preterm infants with ROP.

METHODS AND ANALYSIS

This is a multicentre, open-label, single-arm phase I/II trial. To evaluate the safety and efficacy of ripasudil as much as possible, ripasudil will be administered to all enrolled preterm infants with zone I/II, stage 1, or worse ROP. The safety and efficacy of ripasudil in treated patients will be assessed in comparison to a historical control group. Because this is the first trial of ripasudil in preterm infants, a dose-escalation study (once daily for 1 week, then two times per day for 2 weeks) will be conducted in phase I. After obtaining approval from the independent data and safety monitoring board to continue the trial after the completion of phase I, phase II will be conducted. In phase II, ripasudil eye drops will be administered two times per day for 12 weeks. The primary endpoint in phase II is also safety. Efficacy and pharmacokinetics will be evaluated as secondary endpoints.

ETHICS AND DISSEMINATION

This study protocol was approved by the institutional review board at each of the participating centres. Data will be presented at international conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBERS

NCT04621136 and jRCT2071200047.

Concurrent Physiological and Pathological Angiogenesis in Retinopathy of Prematurity and Emerging Therapies

Retinopathy of prematurity (ROP) is an ocular vascular disease affecting premature infants, characterized by pathological retinal neovascularization (RNV), dilated and tortuous retinal blood vessels, and retinal or vitreous hemorrhages that may lead to retinal detachment, vision impairment and blindness. Compared with other neovascular diseases, ROP is unique because of ongoing and concurrent physiological and pathological angiogenesis in the developing retina. While the disease is currently treated by laser or cryotherapy, anti-vascular endothelial growth factor (VEGF) agents have been extensively investigated but are not approved in the U.S. because of safety concerns that they negatively interfere with physiological angiogenesis of the developing retina. An ideal therapeutic strategy would selectively inhibit pathological but not physiological angiogenesis. Our group recently described a novel strategy that selectively and safely alleviates pathological RNV in animal models of ROP by targeting secretogranin III (Scg3), a disease-restricted angiogenic factor. The preclinical profile of anti-Scg3 therapy presents a high potential for next-generation disease-targeted anti-angiogenic therapy for the ROP indication. This review focuses on retinal vessel development in neonates, the pathogenesis of ROP and its underlying molecular mechanisms, including different animal models, and provides a summary of current and emerging therapies.

Neurodevelopmental Outcomes Following Intravitreal Bevacizumab With Laser Versus Laser Photocoagulation Alone for Retinopathy of Prematurity

BACKGROUND AND OBJECTIVE

To assess neurodevelopmental outcomes of infants with treatment-warranted retinopathy of prematurity (TW-ROP) treated with intravitreal bevacizumab (IVB) plus diode laser photocoagulation (DLP) compared to DLP alone.

PATIENTS AND METHODS

A retrospective review was performed of infants who underwent treatment for TW-ROP with IVB+DLP or DLP alone from 2010 to 2017. Baseline characteristics and coexisting medical comorbidities were recorded. The presence of neurodevelopmental delay (NDD) at 2-year follow-up and composite Bayley-III scores were recorded.

RESULTS

Sixty-six infants were included in the study; 18 received IVB+DLP, and 48 received DLP alone. Average Bayley-III scores for cognition, language, and motor, as well as rates of documental NDD, did not differ between the groups.

CONCLUSION

This study does not demonstrate an increased risk of NDD in infants with TW-ROP treated with IVB+DLP compared with DLP alone. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:220-224.].

Translational Research in Retinopathy of Prematurity: From Bedside to Bench and Back Again

Retinopathy of prematurity (ROP), a vascular proliferative disease affecting preterm infants, is a leading cause of childhood blindness. Various studies have investigated the pathogenesis of ROP. Clinical experience indicates that oxygen levels are strongly correlated with ROP development, which led to the development of oxygen-induced retinopathy (OIR) as an animal model of ROP. OIR has been used extensively to investigate the molecular mechanisms underlying ROP and to evaluate the efficacy of new drug candidates. Large clinical trials have demonstrated the efficacy of anti-vascular endothelial growth factor (VEGF) agents to treat ROP, and anti-VEGF therapy is presently becoming the first-line treatment worldwide. Anti-VEGF therapy has advantages over conventional treatments, including being minimally invasive with a low risk of refractive error. However, long-term safety concerns and the risk of late recurrence limit this treatment. There is an unmet medical need for novel ROP therapies, which need to be addressed by safe and minimally invasive therapies. The recent progress in biotechnology has contributed greatly to translational research. In this review, we outline how basic ROP research has evolved with clinical experience and the subsequent emergence of new drugs. We discuss previous and ongoing trials and present the candidate molecules expected to become novel targets.

Ranibizumab: A Review in Retinopathy of Prematurity

Ranibizumab (Lucentis^®) is a monoclonal antibody fragment targeted against VEGF-A that is the first approved anti-VEGF agent for the treatment of retinopathy of prematurity (ROP). In the pivotal, randomized, phase III RAINBOW trial in infants with ROP, the majority of intravitreal ranibizumab recipients experienced treatment success at 24 weeks, with a numerically greater treatment success rate in the ranibizumab 0.2 mg (80% of patients) than laser therapy (66%) group without reaching statistical significance for superiority. Long-term effects on vision following ranibizumab treatment are not yet known, but interim analyses from the RAINBOW extension study do not show evidence of degraded vision. Adverse reactions to ranibizumab in pediatric patients were consistent with the known safety profile in adults, with most adverse reactions attributed to the intravitreal injection procedure. Furthermore, systemic VEGF suppression was not observed in clinical trials, which is congruent with the rapid systemic clearance of ranibizumab. Overall, ranibizumab is an effective and generally well tolerated treatment for ROP and is not associated with systemic VEGF suppression. Although results for its long-term effects on vision are not yet available, ranibizumab is a promising alternative option to laser therapy for treating ROP.

Long-term macular vascular density measured by OCT-A in children with retinopathy of prematurity with and without need of laser treatment

PURPOSE

To assess long-term vascular density measured by optical coherence tomography angiography (OCT-A) in former preterm children with history of retinopathy of prematurity (ROP) with and without need of laser treatment.

METHODS

This observational study included former preterm children that developed ROP stage 2 or 3. Infants were divided in two groups according to previous need of laser treatment, and underwent a complete ophthalmologic evaluation, including assessment of macular morphologic and vascular parameters by OCT-A.

RESULTS

Fifteen eyes were included in group 1 (laser-requiring ROP) and 19 in group 2 (non-treated ROP). Group 1 had lower mean gestational age and birth weight values than group 2 (p < 0.001 and p < 0.001, respectively). Best corrected visual acuity (BCVA) was lower in group 1 (0.08 ± 0.04 logMAR vs 0.04 ± 0.07 logMAR, p = 0.03). Laser-requiring ROP had lower vascular parameters, especially of central and internal vascular density (9.15 ± 2.75 vs 10.52 ± 0.86 mm^-1, p = 0.05; 13.74 ± 1.00 vs 15.86 ± 0.64 mm^-1, p = 0.05; respectively), and lower avascular zone circularity (0.58 ± 0.06 vs 0.76 ± 0.02, p < 0.001). Mean macular thickness was higher in group 1 (300.50 ± 10.50 vs 281.11 ± 2.50 μm, p = 0.05). Best corrected visual acuity (BCVA) was correlated with superficial vascular density (p < 0.05).

CONCLUSION

Laser-requiring ROP seems to result in a decrease of long-term BCVA, which is at least partially attributed to a decrease in superficial macular vascular density. However, prematurity degree was more pronounced in children that required treatment, which might have influenced our results.

Risk factors for myopia at 1-year corrected age following laser photocoagulation for retinopathy of prematurity

BACKGROUND/OBJECTIVES

The prevalence of myopia is higher in preterm infants who underwent laser photocoagulation (LPC) for retinopathy of prematurity (ROP). The aim of this study was to investigate factors associated with myopia in preterm infants who undergo LPC for ROP.

SUBJECTS/METHODS

We retrospectively analysed the medical records of preterm infants born at Kyushu University Hospital (October 2008-March 2018) at ≤32 weeks of gestational age or with birth weight ≤1500 g. We evaluated the associations between nine clinical factors and the spherical equivalent at 1-year corrected age by performing multivariable linear regression in LPC-treated ROP patients.

RESULTS

Among the 485 infants enroled, 76 developed ROP requiring treatment. Of these, 71 underwent LPC, which was provided to 63 infants as the primary treatment (LPC alone or the combination therapy of LPC and intravitreal injection of bevacizumab [IVB]) and to eight infants as additional LPC after IVB monotherapy. The results of a refractive examination at 1-year corrected age were available for 110 eyes of 56 infants (78.9%). The mean ± standard deviation of the SE value was -0.5 ± 3.0 dioptres (D). Multivariable linear regression analysis revealed a significant association between laser spot count and SE value (ß = -0.081 ± 0.040 D per 100 spots [mean ± standard error], p = 0.045).

CONCLUSIONS

Our results suggest that an increased laser spot count observed during ROP treatment associates with myopia.

Retinal laser services in Bhutan: a 3-year national survey

BACKGROUND

We conducted this study to report on the indications and types of retinal laser therapy (RLT) performed in Bhutan, knowing which is critical for proper planning and successful delivery of the services.

METHODS

We reviewed the laser registers maintained in the laser rooms and vitreoretinal (VR) operating theatres (including paediatric cases managed under anaesthesia) over three years at the national and the two regional referral hospitals (RRHs). Intraoperative laser treatments (endolaser) were excluded. Patient demography, indications and types of RLT were recorded and quantified. Comparisons of the expected and observed frequencies used Chi-squared tests.

RESULTS

A total of 685 patients, including 8 cases of bilateral retinopathy of prematurity (ROP) received RLT. The majority of patients (411 cases, 60.0%, p < 0.0001) were males. The mean age was 54.1 ± 14.1 years, median 56 years. The most common indications for RLT were diabetic retinopathy (DR) and diabetic macular oedema (DMO) (542 cases, 66.0%), followed by retinal vein occlusion (RVO) (91 cases, 13.3%). Pan-retinal photocoagulation was the most common type of RLT performed (337 cases, 49.2%), followed by modified grid laser (207 cases, 30.2%), sectoral laser (41 cases, 6.0%), and prophylactic laser photocoagulation (33 cases, 4.8%).

CONCLUSIONS

The majority of patients were within working-age. Common indications for RLT were preventable such as DR, DMO and RVO, indicating need to control systemic diseases such as diabetes, hypertension, and dyslipidaemia. Currently, regular RLT is provided only at the national referral hospital in Thimphu, and periodically in the eastern and central RRHs when the retinal specialist visits. There is need to extend the retinal services to the eastern and central RRHs to improve accessibility and patient coverage in these regions challenged with difficult terrain and poor public transport system.

The progress of prophylactic treatment in retinopathy of prematurity

Retinopathy of prematurity (ROP) is a retinal vascular disorder frequently found in premature infants. Different therapeutic strategies have been developed to treat ROP. However, there are still many children with ROP suffering by severe limitations in vision or even blindness. Recently, ROP has been suggested to be caused by abnormal development of the retinal vasculature, but not simply resulted by retinal neovascularization which takes about 4 to 6wk after birth in premature infants. Thus, instead of focusing on how to reduce retinal neovascularization, understanding the pathological changes and mechanisms that occur prior to retinal neovascularization is meaningful, which may lead to identify novel target(s) for the development of novel strategy to promote the healthy growth of retinal blood vessels rather than passively waiting for the appearance of retinal neovascularization and removing it by force. In this review, we discussed recent studies about, 1) the pathogenesis prior to retinal neovascularization in oxygen-induced retinopathy (OIR; a ROP in animal model) and in premature infants with ROP; 2) the preclinical and clinical research on preventive treatment of early OIR and ROP. We will not only highlight the importance of the mechanisms and signalling pathways in regulating early stage of ROP but also will provide guidance for actively exploring novel mechanisms and discovering novel treatments for early phase OIR and ROP prior to retinal neovascularization in the future.

Visual outcome and refractive status in first 3 years of age in preterm infants suffered from laser-treated Type 1 retinopathy of prematurity (ROP): a 6-year retrospective review in a tertiary centre in Hong Kong

PURPOSE

To report the visual outcome and refractive status in first 3 years of age in preterm infants suffered from laser-treated Type 1 retinopathy of prematurity (ROP): a 6-year review in Hong Kong DESIGN: Retrospective case series METHODOLOGY: Clinical records of all infants suffered from Type 1 ROP who had undergone laser therapy between 2007 and 2012 were retrospectively reviewed. Basic demographic data, serial changes of refractive error, visual acuity, severity of ROP and laser were analyzed. Correlation with myopia and astigmatism progression, body weight, height, growth and gestational age were also analyzed.

RESULT

Among 494 babies screened, 14 Chinese babies (26 eyes) recruited with 1:1 male-to-female ratio in this study. All eyes showed gradual progression of myopia in first 3 years of age but no significant change of astigmatism. Further correlation analysis showed no correlation with laser energy consumed, birth weight (p = 0.14), head circumference growth (p = 0.57) and body weight growth (p = 0.71). However, severity of myopia was related to the post-conceptual age when receiving laser therapy (p < 0.005), gestation age (p = 0.02) and possibly body height growth with age (p = 0.05).

CONCLUSION

Myopia in early life is one of the most common ocular sequelae in Type 1 ROP survivors. Early detection of refractive error is important for prompt correction and visual rehabilitation to prevent amblyopia.

Time at treatment of severe retinopathy of prematurity in China: recommendations for guidelines in more mature infants

PURPOSE

To investigate the postmenstrual (PMA) age at treatment of severe retinopathy of prematurity (i.e. Type 1 prethreshold or threshold) in infants in a tertiary referral center in China.

PRINCIPAL FINDINGS

76.6% (359/469) of infants were treated for threshold disease. 67.5% (317/469) of infants had a birth weight (BW) of 1250 g or above and almost 30% (126) had a gestational age (GA) of 32 weeks or above. There was little difference in the characteristics of infants treated for Type 1 prethreshold or threshold ROP. After controlling for GA, PMA age at treatment was highest in infants with BW ≥2000 g (mean PMA 40.3±4.4 weeks, p<0.001); after controlling for BW, higher GA was associated with higher PMA at treatment (mean PMA 41.5 weeks for gestational age >34 weeks, p<0.001). For every three weeks increase in GA there was a two-week increase in PMA at treatment (R2 = 0.20, p<0.001). The time at treatment of Type 1 prethreshold disease was similar to that for threshold disease i.e. chronological age 5.6∓7.4 weeks, or PMA 34.1∓40.2 weeks but the lower end of the 95% confidence interval for chronological age for Type 1 prethreshold disease among infants with BW ≥2000 g was 3.7 weeks (i.e. before the recommended interval of 4∓6 weeks after birth).

SIGNIFICANCE

The Chinese guidelines regarding timing of the first examination are appropriate for infants with BW <2000 g, but more mature infants should be examined a little earlier, at 3 weeks after birth, in order to detect Type 1 prethreshold disease which has a better prognosis than threshold.

Evanescent field: a potential light-tool for theranostics application

A noninvasive or minimally invasive optical approach for theranostics, which would reinforce diagnosis, treatment, and preferably guidance simultaneously, is considered to be major challenge in biomedical instrument design. In the present work, we have developed an evanescent field-based fiber optic strategy for the potential theranostics application in hyperbilirubinemia, an increased concentration of bilirubin in the blood and is a potential cause of permanent brain damage or even death in newborn babies. Potential problem of bilirubin deposition on the hydroxylated fiber surface at physiological pH (7.4), that masks the sensing efficacy and extraction of information of the pigment level, has also been addressed. Removal of bilirubin in a blood-phantom (hemoglobin and human serum albumin) solution from an enhanced level of 77 μM/l (human jaundice >50 μM/l) to ~30 μM/l (normal level ~25 μM/l in human) using our strategy has been successfully demonstrated. In a model experiment using chromatography paper as a mimic of biological membrane, we have shown efficient degradation of the bilirubin under continuous monitoring for guidance of immediate/future course of action.

The use of digital imaging in the identification of skip areas after laser treatment for retinopathy of prematurity and its implications for education and patient care

PURPOSE

To describe the utility of using wide-angle digital imaging in the training for retinopathy of prematurity with laser and in identifying common locations of skip areas that were present after initial panretinal photocoagulation with indirect ophthalmoscopy by ophthalmologists-in-training.

METHODS

Retrospective review of digital retinal images of 22 eyes of 12 infants who had undergone laser treatment for retinopathy of prematurity performed by ophthalmologists-in-training. Presence of skip areas was determined by masked review of photographs. The location of skip areas was classified based on two axes: 1) circumferential (in one of six clock-hour regions) and 2) radial (adjacent to the retinal ridge, adjacent to the ora serrata, or isolated patches of greater than one laser burn width).

RESULTS

A total of 30 skip areas were identified in the 22 eyes treated with laser photocoagulation. Based on the circumferential location, a significant difference in skip area distribution was found (P = 0.02). Regions with the highest percentage of skip areas were between the clock hours 11:00 to 1:00 (45%) and 5:00 to 7:00 (41%). Based on the radial location, 40% of all skip areas were found near the ora serrata, 17% near the ridge, and 43% as isolated patches (P = 0.14).

CONCLUSION

Skip areas after indirect panretinal laser photocoagulation by ophthalmologists-in-training were easily visualized by wide-angle digital imaging, after being missed by the trainee during the initial treatment procedure. Most skip areas in this study occurred in the superior or inferior retina. Digital imaging can assist ophthalmologists in visualizing all regions of the retina, can identify inadequate areas of laser treatment, and may reduce the need for retreatment after initial laser for retinopathy of prematurity.