Severe cerebral injury in a recipient with twin anemia-polycythemia sequence.

Twin anemia-polycythemia sequence (TAPS) results from slow intertwin blood transfusion through minuscule placental vascular anastomoses and is characterized by large intertwin hemoglobin differences in the absence of amniotic fluid discordance. The optimal management of TAPS is not clear. We report a case of TAPS detected antenatally by Doppler ultrasound examination at 15 + 6 weeks' gestation. After counseling, the parents opted for expectant management. Regular Doppler measurements were performed and these remained fairly stable. An emergency Cesarean section was performed at 34 + 5 weeks following signs of fetal distress. The donor twin was severely anemic while the recipient twin had severe polycythemia-hyperviscosity syndrome. On day 1, the recipient developed respiratory insufficiency and subclinical status epilepticus. Magnetic resonance imaging showed a total loss of gray-white matter differentiation as a sign of severe diffuse cerebral ischemia and bilateral intra- and extra-axial hemorrhages. There was almost complete lack of arterial and venous cerebral blood flow. On day 3 intensive care treatment was withdrawn in view of the severity of the brain injury. This case report demonstrates that TAPS may lead to severe cerebral injury and fatal outcome in the recipient twin, and highlights the importance of antenatal Doppler ultrasound monitoring and choice of management.

Impact of neonate haematocrit variability on the longitudinal relaxation time of blood: Implications for arterial spin labelling MRI.

BACKGROUND AND PURPOSE: The longitudinal relaxation time of blood (T 1b) is influenced by haematocrit (Hct) which is known to vary in neonates. The purpose of this study was threefold: to obtain T 1b values in neonates, to investigate how the T 1b influences quantitative arterial spin labelling (ASL), and to evaluate if known relationships between T 1b and haematocrit (Hct) hold true when Hct is measured by means of a point-of-care device. MATERIALS AND METHODS: One hundred and four neonates with 120 MR scan sessions (3 T) were included. The T 1b was obtained from a T 1 inversion recovery sequence. T 1b-induced changes in ASL cerebral blood flow estimates were evaluated. The Hct was obtained by means of a point-of-care device. Linear regression analysis was used to investigate the relation between Hct and MRI-derived R1 of blood (the inverse of the T 1b). RESULTS: Mean T 1b was 1.85 s (sd 0.2 s). The mean T 1b in preterm neonates was 1.77 s, 1.89 s in preterm neonates scanned at term-equivalent age (TEA) and 1.81 s in diseased neonates. The T 1b in the TEA was significantly different from the T 1b in the preterm (p < 0.05). The change in perfusion induced by the T 1b was -11% (sd 9.1%, p < 0.001). The relation between arterial-drawn Hct and R1b was R1b = 0.80 × Hct + 0.22, which falls within the confidence interval of the previously established relationships, whereas capillary-drawn Hct did not correlate with R1b. CONCLUSION: We demonstrated a wide variability of the T 1b in neonates and the implications it could have in methods relying on the actual T 1b as for instance ASL. It was concluded that arterial-drawn Hct values obtained from a point-of-care device can be used to infer the T 1b whereas our data did not support the use of capillary-drawn Hct for T 1b correction.

Brain tissue volumes in preterm infants: prematurity, perinatal risk factors and neurodevelopmental outcome: a systematic review.

OBJECTIVE: To evaluate the clinical value of neonatal brain tissue segmentation in preterm infants according to the literature. METHODS: A structured literature search was undertaken in MEDLINE/Pubmed. This included all publications on volumetric brain tissue assessment in preterm infants at term-equivalent age (TEA) compared to brain tissue volumes of term-born infants, related to perinatal risk factors or related to neurodevelopmental outcome. RESULTS: Sixteen prospective cohort studies, described in 30 articles, fulfilled the criteria. Preterm infants displayed total and regional brain tissue alterations compared to healthy, term-born controls. These alterations seemed more prominent with decreasing gestational age. White matter injury, intraventricular haemorrhage, postnatal corticosteroid therapy, intra-uterine growth retardation and chronic lung disease were frequently associated with volume changes. Associations between volume alterations at TEA and neurodevelopmental outcome in early childhood were shown in a few studies. CONCLUSIONS: Preterm birth is associated with brain tissue volume alterations that become more pronounced in the presence of perinatal risk factors and white matter injury. Moreover, associations between volumetric alterations as early as TEA and long-term neurodevelopmental impairments are scarce.

The spectrum of associated brain lesions in cerebral sinovenous thrombosis: relation to gestational age and outcome.

OBJECTIVE: To describe different patterns of associated brain lesions in preterm and full-term infants with cerebral sinovenous thrombosis (CSVT) and to assess whether these different patterns are related to gestational age at onset. DESIGN: Magnetic resonance scans of all neonates (six preterm, 24 full term) with suspected CSVT, collected over a 7-year period in two neonatal intensive care units, were evaluated to assess patterns of associated brain lesions. Comparisons between the two gestational age groups were made. RESULTS: CSVT was confirmed on magnetic resonance venography in 26 of 30 neonates (six preterm, 20≥36 weeks' gestational age). The straight (85%) and superior sagittal (65%) sinus were most often affected. Several sinuses were involved in 81% of infants. White matter damage affecting the entire periventricular white matter was seen in five of six preterm infants. Intraventricular haemorrhage (IVH) was common in both groups (4/6 preterm, 16/20 full term). Frontal punctate white matter lesions with restricted diffusion (15/20) and thalamic haemorrhage associated with IVH (11/20) were the most frequent lesions in full-term infants. Focal arterial infarction was present in four of 20 full-term infants. Six infants died in the neonatal period (four preterm, two full term). Follow-up MRIs at 3 months in all survivors showed evolution of the lesions with frontal atrophy in 13 of 20 (12 full term) and delayed myelination in seven of 20 (six full term). CONCLUSIONS: Preterm and full-term neonates show different patterns of associated brain lesions. Extensive white matter damage is the predominant pattern of injury in the preterm infant, while an IVH associated with a thalamic haemorrhage and punctate white matter lesions are more common in the full-term infant.