Ophthalmological outcome and visuospatial ability in very preterm children measured at 2.5 years corrected age

Brain MRI findings and their association with visual impairment in young adolescents born very preterm

PURPOSE

Very preterm birth increases risk for neonatal white matter injury, but there is limited data on to what extent this persists into adolescence and how this relates to ophthalmological outcomes. The aim of this study was to assess brain MRI findings in 12-year-old children born very preterm compared to controls and their association with concurrent ophthalmological outcomes.

METHODS

We included 47 children born very preterm and 22 full-term controls (gestational age <32 and >37 weeks, respectively). Brain MRI findings were studied in association with concurrent ophthalmological outcomes at 12-year follow-up.

RESULTS

Evans index (0.27 vs 0.25, p<0.001) and a proposed "posterior ventricle index" (0.47 vs 0.45, p=0.018) were increased in children born very preterm. Higher gestational age associated with larger corpus callosum area (β=10.7, 95%CI 0.59-20.8). Focal white matter lesions were observed in 15 (32%) of very preterm children and in 1 (5%) of full-term controls. Increased posterior ventricle index increased risk for visual acuity ≤1.0 (OR=1.07×1011, 95%CI=7.78-1.48×1021) and contrast sensitivity <0.5 (OR=2.6×1027, 95%CI=1.9×108-3.5×1046). Decreased peritrigonal white matter thickness associated with impaired visual acuity (β=0.04, 95%CI 0.002-0.07).

CONCLUSION

More white matter lesions and evidence of lower white matter volume were found in children born very preterm compared with full-term controls at 12-year follow-up. The association between larger posterior ventricle index and reduced visual acuity and contrast sensitivity suggests disturbances of the posterior visual pathway due to diffuse white matter lesions.

Average 2.5-year neurodevelopmental test results in children born very preterm did not rule out cognitive deficits at 6.5 years of age

Aim

The aim of the study was to investigate cognitive outcomes at 6.5 years in children born very preterm, in relation to neonatal characteristics and 2.5‐year neurodevelopment.

Methods

A prospective cohort, with gestational age 22.3‐31.9 weeks, born 2004‐2007, were examined at 2.5 years with the Bayley Scales of Infant and Toddler Development (Bayley‐III) (n = 100) and at 6.5 years with the Wechsler Intelligence Scales (n = 91).

Results

Neonatal factors independently related to 6.5‐year outcome were gestational age, retinopathy of prematurity and treated persistent ductus arteriosus. The Bayley‐III cognitive scores explained only 44% of the Full‐Scale Intelligence Quotient result at 6.5 years, and 22% of the children had Wechsler index results below −1 SD, indicating cognitive impairment, after average test results at 2.5 years. The relative risk to score below −1 SD on the Full‐Scale IQ was 2.83 (95% CI 1.45‐5.53) in children with gestational age below 28 weeks and 2.22 (95% CI 1.18‐4.17) at gestational age 28‐31 weeks.

Conclusion

Very preterm infants born in the 2000s had increased risks for impaired cognition at 6.5 years, but individual predictions based on neonatal risks and 2.5‐year test results were not enough to identify all high‐risk children.

Disruption and Compensation of Sulcation-based Covariance Networks in Neonatal Brain Growth after Perinatal Injury

Perinatal brain injuries in preterm neonates are associated with alterations in structural neurodevelopment, leading to impaired cognition, motor coordination, and behavior. However, it remains unknown how such injuries affect postnatal cortical folding and structural covariance networks, which indicate functional parcellation and reciprocal brain connectivity. Studying 229 magnetic resonance scans from 158 preterm neonates (n = 158, mean age = 28.2), we found that severe injuries including intraventricular hemorrhage, periventricular leukomalacia, and ventriculomegaly lead to significantly reduced cortical folding and increased covariance (hyper-covariance) in only the early (<31 weeks) but not middle (31-35 weeks) or late stage (>35 weeks) of the third trimester. The aberrant hyper-covariance may drive acceleration of cortical folding as a compensatory mechanism to "catch-up" with normal development. By 40 weeks, preterm neonates with/without severe brain injuries exhibited no difference in cortical folding and covariance compared with healthy term neonates. However, graph theory-based analysis showed that even after recovery, severely injured brains exhibit a more segregated, less integrated, and overall inefficient network system with reduced integration strength in the dorsal attention, frontoparietal, limbic, and visual network systems. Ultimately, severe perinatal injuries cause network-level deviations that persist until the late stage of the third trimester and may contribute to neurofunctional impairment.

Impaired cognitive ability at 2.5 years predicts later visual and ophthalmological problems in children born very preterm

AIM

To identify possible predictive factors for visual problems at 6.5 years in children born very preterm.

METHODS

During 2004-2007, all very preterm infants (gestational age [GA] <32 weeks) in Uppsala County, Sweden were screened for retinopathy of prematurity (ROP) neonatally; at four months, visual tracking was tested; at 2.5 years, visuospatial and cognitive tests were carried out. At 6.5 years, 84 preterm children and a reference group of 64 full-term children underwent ophthalmological testing.

RESULTS

Mean visual acuity (VA) did not differ between the groups, but subnormal VA (≤0.8) was more common in the preterm group (31% vs 14%; p < 0.05). More often than full-term children, preterm children had impaired contrast sensitivity (<0.5) (36% vs 19%; p < 0.05) and strabismus (8% vs 0%; p < 0.05). Low GA, ROP, intraventricular haemorrhage 3-4/periventricular leukomalacia and cognitive disability at 2.5 years predicted ophthalmological and visual problems at 6.5 years. Visual tracking ability at four months was not predictive of ophthalmological outcome.

CONCLUSION

Children born preterm had more ophthalmological problems at 6.5 years of age, including subtle dysfunctions. ROP, early brain injury and impaired cognitive function around 2.5 years predicted later ophthalmological dysfunctions.

Ophthalmologic Outcomes of Children Born Premature Without ROP: Correlations With Gestational Age and Psychomotor Development

PURPOSE

To study ophthalmological outcomes of premature children with no retinopathy of prematurity (ROP) and correlate with neurodevelopmental outcomes.

METHODS

A total of 69 former preterm infants were evaluated at 2 to 7 years of age. Detailed ophthalmologic examinations were performed. Neurodevelopment was assessed using the Peabody Developmental Motor Scale and Wechsler Preschool and Primary Scale of Intelligence. Another 69 healthy children served as controls.

RESULTS

The 69 preterm children (38 of 69 boys) and 69 controls (38 of 69 boys) had a mean age of 4.9 ± 1.5 and 4.9 ± 1.4 years, respectively. Compared to controls, preterm infants had vision impairment of 19% versus 1.4% (P = .001), hyperopia of 87% versus 98.5% (P = .21), myopia of 11% versus 1.4% (P = .017), and astigmatism of 39% versus 30.4% (P = .37). Children with any motor disability tended to have worse vision.

CONCLUSIONS

In the absence of ROP, hyperopia was more common in infants 32 weeks or older who weighed more than 1,500 g at birth; other vision problems were similar in subgroups. This may represent impending myopia in those younger than 32 weeks weighing less than 1,500 g. [J Pediatr Ophthalmol Strabismus. 2017;54(1):32-38.].

Visual tracking in very preterm infants at 4 mo predicts neurodevelopment at 3 y of age

BACKGROUND

Typically developing infants track moving objects with eye and head movements in a smooth and predictive way at 4 mo of age, but this ability is delayed in very preterm infants. We hypothesized that visual tracking ability in very preterm infants predicts later neurodevelopment.

METHOD

In 67 very preterm infants (gestational age<32 wk), eye and head movements were assessed at 4 mo corrected age while the infant tracked a moving object. Gaze gain, smooth pursuit, head movements, and timing of gaze relative the object were analyzed off line. Results of the five subscales included in the Bayley Scales of Infant Development (BSID-III) at 3 y of age were evaluated in relation to the visual tracking data and to perinatal risk factors.

RESULTS

Significant correlations were obtained between gaze gain and cognition, receptive and expressive language, and fine motor function, respectively, also after controlling for gestational age, severe brain damage, retinopathy of prematurity, and bronchopulmonary dysplasia.

CONCLUSION

This is the first study demonstrating that the basic ability to visually track a moving object at 4 mo robustly predicts neurodevelopment at 3 y of age in children born very preterm.

Comparison of Refractive Error Changes in Retinopathy of Prematurity Patients Treated with Diode and Red Lasers

Aim: To compare refractive error changes in retinopathy of prematurity (ROP) patients treated with diode and red lasers. Methods: A randomized double-masked clinical trial was performed, and infants with threshold or prethreshold type 1 ROP were assigned to red or diode laser groups. Gestational age, birth weight, pretreatment cycloplegic refraction, time of treatment, disease stage, zone and disease severity were recorded. Patients received either red or diode laser treatment and were regularly followed up for retina assessment and refraction. The information at month 12 of corrected age was considered for comparison. Results: One hundred and fifty eyes of 75 infants were enrolled in the study. Seventy-four eyes received diode and 76 red laser therapy. The mean gestational age and birth weight of the infants were 28.6 ± 3.2 weeks and 1,441 ± 491 g, respectively. The mean baseline refractive error was +2.3 ± 1.7 dpt. Posttreatment refraction showed a significant myopic shift (mean 2.6 ± 2.0 dpt) with significant difference between the two groups (p < 0.001). There was a greater myopic shift among children with zone I and diode laser treatment (mean 6.00 dpt) and a lesser shift among children with zone II and red laser treatment (mean 1.12 dpt). The linear regression model, using the generalized estimating equation method, showed that the type of laser used has a significant effect on myopic shift even after adjustment for other variables. Conclusion: Myopic shift in laser-treated ROP patients is related to the type of laser used and the involved zone. Red laser seems to cause less myopic shift than diode laser, and those with zone I involvement have a greater myopic shift than those with ROP in zone II.