Retinal haemorrhage rates and resolution time of retinal haemorrhage in newborns after hypothermic treatment for hypoxic-ischemic encephalopathy

Evidence for significant misdiagnosis of abusive head trauma in pediBIRN data

Independently witnessed events are used as a reference standard to robustly categorize accidental or non-abusive head trauma (non-AHT) cases in the pediBIRN data set of acutely symptomatic infants with closed head injuries. Findings in such independently witnessed non-AHT cases are compared to findings in cases that were diagnosed as AHT but were not independently witnessed. The data shows that 14% of independently witnessed non-AHT cases are misdiagnosed as AHT, and that risk factors for misdiagnosis include acute encephalopathy, bilateral or interhemispheric SDH, and/or severe retinal hemorrhages, findings that are commonly associated with AHT. The data also shows that "dense retinal hemorrhages extending to the periphery" are not highly suggestive of AHT, as they also occur in independently witnessed non-AHT cases.

Retinal vascular recovery revealed by retinal imaging following neonatal hypoxia ischemia in mice: Is there a role for tyrosine kinase receptor modulation?

OBJECTIVE

Hypoxic ischemic encephalopathy (HIE) secondary to perinatal asphyxia leads to long-term visual disabilities. Dilated retinal exams in human newborns with HIE is an emerging diagnostic tool, but phenotypes of hypoxia ischemia (HI) related retinal vascular injury are unclear. 7,8-Dihydroxyflavone (7,8-DHF) is a TrkB agonist with protective effects on HI-related brain damage. We studied retinal vessels in a mouse model of neonatal HIE and the efficacy of 7,8-DHF in ameliorating HI-related retinal vascular injury.

METHODS

C57BL6/J mice at post-natal day (P) 9 received unilateral left carotid artery ligation followed by exposure to 10 % oxygen for 50 min. Phosphate buffered saline or 7,8-DHF (5 mg/kg) were administered daily for 7 days intraperitoneally. Control groups of naïve or carotid artery ligation only mice were studied. Fluorescein angiography was performed in acute (two weeks post-exposure) and chronic (four weeks post-exposure) time points. Retinal artery width, retinal vein width, and collateral vessel length were quantified.

RESULTS

Ligation of the common carotid artery alone caused retinal artery dilation in acute and chronic time points, but had no effect on retinal veins. At acute time point, HI caused increased retinal artery vasodilation, but was reversed by 7,8-DHF. HI caused short collateral vessel formation in ipsilateral eyes, rescued by 7,8-DHF treatment.

CONCLUSION

Retinal artery vasodilation and collateral vessel formation due to HI were rescued by 7,8-DHF treatment. Retinal and collateral vessel monitoring could be diagnostic biomarkers for HI severity. Studies to elucidate mechanisms of 7,8-DHF action on retinal vessels could aid development of therapies for neonatal HI.

Prevalence, Characteristics, and Risk Factors of Retinal Hemorrhage among Full-Term Neonates in Southern China

Neonatal retinal hemorrhage (RH) is the most common ocular fundus disease among newborns. Early detection and timely intervention are vital for reducing the risk of visual impairment caused by RH. However, little is known about the prevalence, characteristics, and risk factors of RH in southern China. Full-term infants born in Qingyuan City during the first 10 days of each month in 2021 were included in this study. All infants underwent RetCam III retinal examinations. Detailed information on retinal hemorrhage, including involved eyes, bleeding severity, and affected area (extrafoveal macula, fovea, or optic disc), and clinical information on the neonates and their mothers was collected. The results showed that among the 1072 eligible neonates, 266 (24.8%) had neonatal retinal hemorrhage. Consistent bilateral retinal hemorrhage severity was observed in 83.2% of the cases. The prevalence of optic disc involved RH, extrafoveal macular involved RH and foveal involved RH were 23.7%, 81.2% and 2.63%, respectively. Multivariate logistic regression analysis showed that lower birth weight (OR, 0.63; 95% CI, 0.40-0.99; p < 0.05) and vaginal delivery (OR, 20.6; 95% CI, 9.10-46.5; p < 0.001) were risk factors of neonatal RH. The area under the ROC curve of vaginal delivery, combined with birth weight, as predictors of neonatal RH was 0.73, with 85.3% sensitivity and 23.9% specificity. The birth weight cutoff was 3460 g. Our results suggested that neonatal RH is common in full-term neonates in southern China. It usually has the same severity in both eyes and mostly involves the extrafoveal macular region. Vaginal delivery and low birth weight are risk factors for neonatal RH.

Higher prevalence of fundus haemorrhages in early-screened (NEST Study) as compared to late-screened (SUNDROP Study) newborn populations

BACKGROUND/AIMS

To determine whether timing of ophthalmic screening influences prevalence of neonatal fundus haemorrhages. We compared the prevalence of fundus haemorrhages in two populations: term newborns screened early (less than 72 hours) and preterm newborns screened late (4-11 weeks). Additionally, we reviewed the literature on timing and prevalence of newborn haemorrhages.

METHODS

Retrospective observational cohort study. Infants who underwent wide-angle ophthalmic digital imaging over one overlapping year in the Newborn Eye Screen Testing (NEST) or Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP) programme were included. The PubMed database was filtered to include English-language articles dating back to 1950. Nine articles were selected for review based on inclusion of the prevalence of newborn fundus haemorrhages at multiple time points.

RESULTS

A total of 202 patients received early imaging in the NEST cohort and 73 patients received late imaging in the SUNDROP cohort. In the NEST cohort, 20.2% of newborns had haemorrhages. In contrast, we found haemorrhages in only one case or 1.4% of the SUNDROP cohort. Using prevalence data from nine additional studies, we developed a predicted probabilities model of newborn haemorrhages. Per this model, the probability of seeing a haemorrhage if you screen an infant at 1 hour is 18.8%, at 2 weeks is 2.9% and at 1 month is 0.28%.

CONCLUSION

We found a significant difference in the prevalence of fundus haemorrhages between the early-screened NEST cohort and the late-screened, preterm SUNDROP cohort. Likely, this difference is due to the transient nature of most newborn haemorrhages.