Ipsilesional volume loss of basal ganglia and thalamus is associated with poor hand function after ischemic perinatal stroke.

BACKGROUND: Perinatal stroke (PS) is the leading cause of hemiparetic cerebral palsy (CP). Involvement of the corticospinal tract on neonatal magnetic resonance imaging (MRI) is predictive of motor outcome in patients with hemiparetic CP. However, early MRI is not available in patients with delayed presentation of PS and prediction of hemiparesis severity remains a challenge. AIMS: To evaluate the volumes of the basal ganglia, amygdala, thalamus, and hippocampus following perinatal ischemic stroke in relation to hand motor function in children with a history of PS and to compare the volumes of subcortical structures in children with PS and in healthy controls. METHODS: Term born PS children with arterial ischemic stroke (AIS) (n = 16) and with periventricular venous infarction (PVI) (n = 18) were recruited from the Estonian Pediatric Stroke Database. MRI was accuired during childhood (4-18 years) and the volumes of the basal ganglia, thalamus, amygdala and hippocampus were calculated. The results of stroke patients were compared to the results of 42 age- and sex-matched healthy controls. Affected hand function was evaluated by Assisting Hand Assessment (AHA) and classified by the Manual Ability Classification System (MACS). RESULTS: Compared to the control group, children with AIS had smaller volumes of the ipsi- and contralesional thalami, ipsilesional globus pallidus, nucleus accumbens and hippocampus (p < 0.005). Affected hand function in children with AIS was correlated with smaller ipsilesional thalamus, putamen, globus pallidus, hippocampus, amygdala and contralesional amygdala (r > 0.5; p < 0.05) and larger volume of the contralesional putamen and hippocampus (r < - 0.5; p < 0.05). In children with PVI, size of the ipsilesional caudate nucleus, globus pallidus, thalamus (p ≤ 0.001) and hippocampus (p < 0.03) was smaller compared to controls. Smaller volume of the ipsi- and contralesional thalami and ipsilesional caudate nucleus was correlated with affected hand function (r > 0.55; p < 0.05) in children with PVI. CONCLUSIONS: Smaller volume of ipsilesional thalamus was associated with poor affected hand function regardless of the perinatal stroke subtype. The pattern of correlation between hand function and volume differences in the other subcortical structures varied between children with PVI and AIS. Evaluation of subcortical structures is important in predicting motor outcome following perinatal stroke.

Resting-State Functional Connectivity and Cognitive Impairment in Children with Perinatal Stroke.

Perinatal stroke is a leading cause of congenital hemiparesis and neurocognitive deficits in children. Dysfunctions in the large-scale resting-state functional networks may underlie cognitive and behavioral disability in these children. We studied resting-state functional connectivity in patients with perinatal stroke collected from the Estonian Pediatric Stroke Database. Neurodevelopment of children was assessed by the Pediatric Stroke Outcome Measurement and the Kaufman Assessment Battery. The study included 36 children (age range 7.6-17.9 years): 10 with periventricular venous infarction (PVI), 7 with arterial ischemic stroke (AIS), and 19 controls. There were no differences in severity of hemiparesis between the PVI and AIS groups. A significant increase in default mode network connectivity (FDR 0.1) and lower cognitive functions (p < 0.05) were found in children with AIS compared to the controls and the PVI group. The children with PVI had no significant differences in the resting-state networks compared to the controls and their cognitive functions were normal. Our findings demonstrate impairment in cognitive functions and neural network profile in hemiparetic children with AIS compared to children with PVI and controls. Changes in the resting-state networks found in children with AIS could possibly serve as the underlying derangements of cognitive brain functions in these children.

Long-term neurodevelopmental outcome after perinatal arterial ischemic stroke and periventricular venous infarction.

BACKGROUND: Long-term follow-up data after different vascular types of ischemic perinatal stroke is sparse. Our aim was to study neurodevelopmental outcomes following neonatal and presumed perinatal ischemic middle cerebral artery territory stroke (arterial ischemic stroke, AIS) and periventricular venous infarction (PVI). METHODS: A prospective consecutive cohort of 40 term-born children with perinatal stroke (21 AIS, 19 PVI) was identified through the Estonian Paediatric Stroke Database. While 48% of the children with AIS were diagnosed during the neonatal period, all the children with PVI had presumed perinatal stroke. Outcomes based on the Paediatric Stroke Outcome Measure (PSOM) and Kaufman Assessment Battery for Children - Second Edition (K-ABC-II), in relation to extent and laterality of stroke, were defined. RESULTS: At a median age of 7 years 6 months (range 3.6-13y), there was a trend towards worse neurodevelopmental outcome in participants with AIS when compared to PVI (mean total PSOM scores 3.1 and 2.2, respectively; p = 0.06). Combined deficits of motor, language and cognitive/behavioural functions were significantly more common among children with AIS (90%) when compared to children with PVI (53%, p = 0.007). General cognitive ability (by K-ABC-II) was significantly lower in the AIS subgroup (mean 79.6; 95% CI 72.3-87.0), but children with PVI (91.6; 95% CI 85.5-97.8) also had poorer performance than the age-equivalent normative mean. Large extent of stroke was associated with poorer neurodevelopmental outcome and lower cognitive performance in children following AIS but not in PVI. CONCLUSION: In this national cohort, poor long-term neurodevelopmental outcome after perinatal ischemic stroke was seen irrespective of the vascular type or time of diagnosis of stroke. However, the spectrum of neurological deficits is different after perinatal AIS and PVI, with combined deficits more common among children following AIS.

Epilepsy after perinatal stroke with different vascular subtypes.

OBJECTIVE: With an incidence up to 63 per 100,000 live births, perinatal stroke is an important cause of childhood epilepsy. The aim of the study was to find the prevalence of and predictive factors for epilepsy, and to describe the course of epilepsy in children with perinatal stroke with different vascular subtypes. METHODS: Patients were retrieved from the Estonian Paediatric Stroke Database with follow-up time at least 24 months. Patients were divided into 5 perinatal stroke syndromes: neonatal arterial ischemic stroke (AIS), neonatal hemorrhagic stroke, neonatal cerebral sinovenous thrombosis, presumed AIS, and presumed periventricular venous infarction. RESULTS: The final study group included 73 children with perinatal stroke (39 boys). With a median follow-up time of 8.6 years, epilepsy was diagnosed in 21/73 (29%) children, most of whom had AIS (17/21, 81%). The 18-year cumulative poststroke epilepsy risk according to the Kaplan-Meier estimator was 40.8% (95% confidence interval [CI] 20.7-55.9%). The median age at epilepsy diagnosis was 50 months (range 1 month to 18.4 years). Children with neonatal AIS had the highest risk of epilepsy, but children with presumed AIS more often had severe epilepsy syndromes. Cortical lesions (odds ratio [OR] 19.7, 95% CI 2.9-133), and involvement of thalamus (OR 9.8, 95% CI 1.8-53.5) and temporal lobe (OR 8.3, 95% CI 1.8-39.6) were independently associated with poststroke epilepsy. SIGNIFICANCE: The risk for poststroke epilepsy after perinatal stroke depends on the vascular subtype. Patients with perinatal AIS need close follow-up to detect epilepsy and start with antiepileptic treatment on time.

Presumed Perinatal Stroke: Risk Factors, Clinical and Radiological Findings.

It is unknown why some infants with perinatal stroke present clinical symptoms late during infancy and will be identified as infants with presumed perinatal stroke. The risk factors and clinical and radiological data of 42 infants with presumed perinatal stroke (69% with periventricular venous infarction and 31% with arterial ischemic stroke) from the Estonian Pediatric Stroke Database were reviewed. Children with presumed perinatal stroke were born at term in 95% of the cases and had had no risk factors during pregnancy in 43% of the cases. Children with periventricular venous infarction were born significantly more often (82%) vaginally (P = .0213) compared to children with arterial stroke (42%); nor did they require resuscitation (P = .0212) or had any neurological symptoms after birth (P = .0249). Periventricular venous infarction is the most common type of lesion among infants with the presumed perinatal stroke. Data suggest that the disease is of prenatal origin.