Regression pattern in retinopathy of prematurity

Clinical Features of Spontaneous Regression of Retinopathy of Prematurity in China: A 5-Year Retrospective Case Series

Purpose: The aim of this study is to explore the clinical features of spontaneous regression of retinopathy of prematurity (ROP) in China, including fundus appearance, time course, and affecting factors.

Methods: Data of pediatric patients in whom ROP spontaneously regressed without treatment were collected, including general demographics, medical history, zones and stages of ROP, and changes of fundus appearance. The fundus manifestations of spontaneous regression in ROP were systematically summarized. Meanwhile, the time course of spontaneous regression in ROP was further analyzed, including the onset time, completion time, and duration of regression, which were all compared across different ROP zones and stages. The associated factors were analyzed by survival analysis for their correlation with delayed regression for the first time.

Results: Two hundred thirty-seven eyes of 237 pediatric patients were included. The fundus manifestations of regression differed across stages. Lesions gradually subsided, and the retinal vessels gradually vascularized completely. However, despite ROP regression, some abnormalities remained. We observed avascular retina in the temporal periphery (19.0%), increased vascular branching (6.8%), retinal pigmentary changes (6.8%), and smaller angle between the upper and lower temporal retinal vessel trunks (3.0%). Acute ROP started to regress at a median 40 weeks of postmenstrual age (PMA) and completely regressed by median 49.0 weeks of PMA. The median duration for regression was 8.5 weeks. The zone II ROP and stage 3 ROP had a later time for onset and completion of regression, and longer duration. Anemia and retinal hemorrhage (RH) were identified as independent risk factors for delayed regression by survival analysis.

Conclusions: During spontaneous regression, the fundus appearance is diverse, and the retinal vessels gradually vascularized completely. The time course of regression differs depending on the ROP zone and stage. Anemia and RH are independent risk factors for delayed regression. Further research of the natural course of the regression of ROP is needed to help design effective screening and follow-up plans.

Vascular changes on fluorescein angiography of premature infants with low risk of retinopathy of prematurity after high oxygen exposure

Purpose

To describe a wide array of peripheral vascular changes using fluorescein angiography in preterm neonates, without high risk characteristics for developing retinopathy of prematurity, that were exposed to high oxygen concentration.

Methods

Retrospective, two center, case series. Newborns at two different hospitals with ≥1500 g or gestational age of ≥32 weeks, fluorescein angiography performed, and with high oxygen exposure without adequate control were included.

Results

294 infants diagnosed with ROP were analyzed. Only 28 eyes from 14 patients with peripheral vascular abnormalities in older and heavier babies were included. Two distinct type of peripheral vascular changes were observed: group 1 or non-proliferative: areas of capillary non-perfusion along with widespread arteriovenous shunting between adjacent primary vessels, tortuosity of primary vessels, abnormal budding of tertiary vessels and capillaries, abnormal capillary tufts and absence of foveal avascular zone; group 2 or proliferative: all of the characteristics of group 1 plus leakage of dye from the boundary between perfused and non-perfused retina and/or optic disc.

Conclusion

Peripheral vascular abnormalities different from retinopathy of prematurity are observed in older than 32 weeks of gestational age, and heavier than 1500 g babies. This makes the authors classify these patients as having a disease caused solely by oxygen dysregulation at the neonatal intensive care unit similarly to the oxygen induced retinopathy in experimental studies.

Chronic Vascular Arrest as a Predictor of Bevacizumab Treatment Failure in Retinopathy of Prematurity

PURPOSE

To describe a pattern of retinopathy of prematurity (ROP) disease regression and chronic vascular arrest after intravitreal bevacizumab treatment that is not observed after peripheral laser ablation.

DESIGN

Single-institution retrospective cohort study.

PARTICIPANTS

Consecutive sample of 58 eyes in 30 patients treated for type 1 ROP.

METHODS

Initial treatment with either a single intravitreal injection of bevacizumab in off-label use (n = 33 eyes) or peripheral laser ablation (n = 25 eyes) as part of standard clinical care. There was bias in recommending off-label bevacizumab for smaller infants with type 1 ROP.

MAIN OUTCOME AND MEASURES

Reactivation or persistence of ROP, as determined by clinical examination, fundus photography, and fluorescein angiography.

RESULTS

All eyes treated initially with bevacizumab demonstrated irregular progression of the leading vascular edge in a stereotyped pattern, suggestive of scalloped regression. Recurrence, based on angiographic demonstration of leakage, or chronic vascular arrest, confirmed based on angiographic demonstration of peripheral ischemia, was noted in 30 eyes (91%) in the bevacizumab group, at a median interval of 14.9 weeks after injection (corrected gestational age, 49.3 weeks). Univariate logistic regression indicated that the need for rescue treatment was associated with decreased birth weight (odds ratio [OR], -0.007; P = 0.04) and age of initial treatment (OR, -0.35; P = 0.05), but not gender, race, or gestational age. Multivariate logistic regression indicated that only decreased birth weight (OR, -0.018; P = 0.04) was associated with need for rescue treatment.

CONCLUSIONS

Treating ROP with intravitreal bevacizumab results in a characteristic scalloped regression pattern that is highly associated with treatment using biologic anti-vascular endothelial growth factor agents. The presence of this pattern in conjunction with chronic vascular arrest and peripheral retinal ischemia persisting beyond standard screening timelines has significant implications for the management of ROP. Fluorescein angiography is important in assessing vascular maturation in these infants.

Involution patterns of retinopathy of prematurity after treatment with intravitreal bevacizumab: implications for follow-up

PURPOSE

To describe involution patterns following monotherapy with intravitreal bevacizumab injection (IVB) for type 1 retinopathy of prematurity (ROP) in zone I or zone II posterior.

METHODS

A retrospective chart review of infants treated with IVB from January 2010-April 2014. Infants with minimum of 82 weeks postmenstrual age at last follow-up were included. Primary outcome was timing of involution of type 1 ROP for the first 12 weeks post treatment. Secondary outcomes were development of any recurrence and structural outcome at last follow-up. Retinal examination records, fundus, and flourescein angiography images were reviewed.

RESULTS

Twenty-eight eyes were included. Average follow-up post treatment was 33.9±9.7 months (range 21.4-61.9). Cumulative frequency of regression of plus disease was seen in 73.3, 86.7, and 100% of eyes by days 3, 5, and 8, respectively. Regression of both stage 3 and plus disease was observed in 29, 82, 88, and 100% by weeks 1, 2, 3, and 4, respectively. Within the first 3 months, 17/28 eyes developed recurrence to stage 1 or 2 after regression. None developed recurrence of plus disease. By the end of 3 months 18% of eyes vascularized into zone III. At a mean of 24±17.3 months, 39% of eyes were not vascularized into zone III as seen on flourescein angiography with scleral indentation.

CONCLUSION

Our experience suggests regression of plus disease and stage 3 are expected within the first 4 weeks after bevacizumab treatment. Recurrence may occur despite initial regression and requires careful follow-up.

Imaging Retinal Vascular Changes in the Mouse Model of Oxygen-Induced Retinopathy

PURPOSE

Oxygen-induced retinopathy in the mouse is the standard experimental model of retinopathy of prematurity. Assessment of the pathology involves in vitro analysis of retinal vaso-obliteration and retinal neovascularization. The authors studied the clinical features of oxygen-induced retinopathy in vivo using topical endoscopy fundus imaging (TEFI), in comparison to standard investigations, and evaluated a system for grading these features.

METHODS

Postnatal day (P)7 mice were exposed to 75% oxygen for five days to induce retinopathy or maintained in room air as controls. Retinal vascular competence was graded against standard photographs by three masked graders. Retinal photographs were obtained at predetermined ages using TEFI. Postmortem, retinal vaso-obliteration was measured in whole mounts with labeled vasculature, and retinal neovascularization was quantified in hematoxylin- and eosin-stained ocular cross sections.

RESULTS

Fundus photography by TEFI was possible from P15, when retinal vascular incompetence, including dilatation and tortuosity, was significant in mice with oxygen-induced retinopathy in comparison to controls. Vascular incompetence peaked in severity at P17 and persisted through P25. Comparison with in vitro analyses indicated that vascular changes were most severe after retinal avascularity had begun to decrease in area, and coincident with the maximum of retinal neovascularization. A weighted Fleiss-Cohen kappa indicated good intra- and interobserver agreement for a 5-point grading system.

CONCLUSIONS

Topical endoscopy fundus imaging demonstrates retinal vascular incompetence in mice with oxygen-induced retinopathy. The technique complements standard postmortem analysis for following the course of the model.

TRANSLATIONAL RELEVANCE

Topical endoscopy fundus imaging has application in the evaluation of novel biologic drugs for retinopathy of prematurity.

Pulsed mode versus near-continuous mode delivery of diode laser photocoagulation for high-risk retinopathy of prematurity

OBJECTIVE

To compare structural and functional outcomes and efficiency of diode laser photocoagulation for retinopathy of prematurity (ROP) when delivered in a pulsed mode versus a near-continuous mode.

METHODS

A retrospective study was conducted of 138 patients who underwent diode laser photocoagulation for threshold ROP using either pulsed or near-continuous delivery. Laser-related complications and structural and functional outcomes were analyzed. Prospectively, time efficiency and total energy used were evaluated in nine infants with bilateral symmetric high-risk prethreshold ROP in which one eye of each infant was randomized to pulsed and the fellow eye to near-continuous delivery.

RESULTS

There was no significant difference between groups with regards to prevalence of posterior disease (Zone 1 or posterior Zone 2) (p = 0.11), postoperative vitreous haze (p = 0.60), postoperative complications (p = 0.38), retinal detachment (p = 0.90), strabismus (p = 0.73), amblyopia (p = 0.69), or refractive error (p = 0.95). Mean time for treatment was 23 minutes using pulsed delivery versus 14 minutes per eye with near-continuous delivery (p < 0.001). The mean total power used per eye with pulsed mode delivery was 1.5 x 10(5) W versus 1.1 x 10(5) W with near-continuous delivery (p = 0.015).

CONCLUSIONS

No differences in complications, functional outcome, or structural outcome were found between using pulsed mode and near-continuous mode diode laser delivery for high-risk ROP. Near-continuous laser delivery, in our hands, was more time-efficient and used less total power.

Involution of retinopathy of prematurity after laser treatment: factors associated with development of retinal detachment

PURPOSE

To identify specific features during the process of involution of retinopathy of prematurity after treatment at threshold that are associated with development of a retinal detachment.

DESIGN

Retrospective case series.

METHODS

The evolution of retinal detachments over time was analyzed retrospectively in 262 treated eyes of 138 infants. Specific features hypothesized to be associated with development of a retinal detachment were analyzed, including vitreous organization defined as clinically important, active stage 3 disease and active plus disease more than 21 days after treatment, and vitreous hemorrhage defined as clinically important.

RESULTS

A retinal detachment developed in 36 (13.7%) of 262 eyes. Vitreous organization meeting our clinically important definition was associated with a 31-fold (confidence interval [CI] 5.37-183.63; P < .0001) and 13-fold (CI 2.97-58.59; P < .0001) increase in the odds for retinal detachment for right and left eyes, respectively. Vitreous hemorrhage defined as clinically important was associated with a 38-fold (CI 2.69-551.19; P = .007) and 15-fold (CI 1.65-144.12; P = .02) increase in the odds for retinal detachment for right and left eyes, respectively. The timing of retinal detachment relative to vitreous hemorrhage was not determined. Prolonged activity of Stage 3 disease or plus disease more than 21 days after treatment was not associated with development of a retinal detachment.

CONCLUSIONS

Clinically important vitreous organization and vitreous hemorrhage were predictive for development of a retinal detachment. Evaluation of preemptive reintervention strategies for eyes at highest risk for developing a retinal detachment may be reasonable.

Involution of threshold retinopathy of prematurity after diode laser photocoagulation

OBJECTIVE

To characterize the process of involution of threshold retinopathy of prematurity after transpupillary diode laser photocoagulation.

DESIGN

Retrospective case series.

PARTICIPANTS

Neonates with threshold retinopathy who underwent diode laser photocoagulation of the peripheral avascular retina.

METHODS

A retrospective chart review was done of the weekly examination records of infants treated for threshold disease. Features that were studied included the presence of residual stage 3 neovascularization, plus disease, and development of retinal detachment (RD).

MAIN OUTCOME MEASURES

Timing of full involution and/or development of an RD.

RESULTS

Of 262 eyes of 138 infants treated, full involution without RD was seen in 8%, 43%, 64%, 73%, and 86% of eyes at postoperative weeks 1, 2, 3, 4, and 9+/-3, respectively. Retinal detachments were diagnosed cumulatively in 0%, 1.5%, 4.2%, 6.5%, and 14% of eyes at weeks 1, 2, 3, 4, and 9+/-3, respectively.

CONCLUSIONS

Full involution of laser-treated threshold retinopathy of prematurity required more than 2 weeks in more than half of treated eyes. Most RDs were not detected until > or =3 weeks after treatment.

Threshold stage of retinopathy of prematurity: maternal and neonatal risk factors

BACKGROUND

The aim of this study was to review the maternal and neonatal risk factors associated with retinopathy of prematurity (ROP) and the threshold stage of the disease.

PATIENTS AND METHODS

In this prospective cohort study, all preterm infants of less than 1501 g birth weight were screened for ROP between January 1996 and December 1997 at the neonatal unit of the Maternity Hospital in Kuwait. The rate of the threshold stage of ROP, as well as risk factors associated with the disease, were identified.

RESULTS

A total of 234 babies were screened for ROP, of which 151 (64.5%) developed the disease and 34 (14.5%) had the threshold stage of ROP. Several factors were found to be associated with ROP and threshold ROP. Stepwise regression analysis revealed that low birth weight (P<0.002) and exposure to high oxygen concentration (P<0.0001) were independently associated with ROP. In addition, low birth weight (P<0.006), high oxygen concentration (P<0.003), and culture-proven sepsis (P<0.04) were found to be independent predictors of threshold ROP.

CONCLUSION

Apart from low birth weight and exposure to high oxygen therapy, which are well-documented risk factors of ROP, septicemia was also found to be associated with the threshold stage of ROP.