Imaging of cerebral complications of extracorporeal membrane oxygenation in infants with congenital heart disease - ultrasound with multimodality correlation.

Cranial ultrasound on neonatal intensive care units is generally performed by intensive care physicians, but radiologists often provide this crucial bedside test to children on specialist paediatric cardiac intensive care units. On a paediatric cardiac intensive care unit, complex congenital cardiac conditions are commonly encountered in both pre- and postoperative scenarios, often with the use of extracorporeal membrane oxygenation (ECMO), which both increases the risks of a number of neurologic complications and results in significant changes in vascular physiology. The aim of this pictorial essay is to discuss cranial ultrasound technique, demonstrate the changes in Doppler flow profiles resulting from veno-arterial extracorporeal membrane oxygenation and congenital cardiac conditions, and illustrate commonly encountered intracranial complications of extracorporeal membrane oxygenation support in congenital cardiac care.

Disseminated cerebral hydatid disease (multiple intracranial echinococcosis).

Intracranial echinococcosis is relatively uncommon and usually occurs in the context of echinococcal lesions elsewhere in the body, mostly liver and lung. Multiple intracranial lesions can result from rupture of an initial single intracranial cyst (in cystic echinococcosis) or from dissemination of systemic disease of the lung, liver or heart (cystic and alveolar echinococcosis). The two main subtypes, cystic and alveolar echinococcosis, present differently and have distinct imaging features in the brain. We discuss the presentation, imaging findings and clinical course of three cases (two cystic and one alveolar) of intracranial echinococcal disease in adults.

Regional changes in thalamic shape and volume with increasing age.

The thalamus undergoes significant volume loss and microstructural change with increasing age. Alterations in thalamo-cortical connectivity may contribute to the decline in cognitive ability associated with aging. The aim of this study was to assess changes in thalamic shape and in the volume and diffusivity of thalamic regions parcellated by their connectivity to specific cortical regions in order to test the hypothesis age related thalamic change primarily affects thalamic nuclei connecting to the frontal cortex. Using structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI), we assessed thalamic volume and diffusivity in 86 healthy volunteers, median (range) age 44 (20-74) years. Regional thalamic micro and macro structural changes were assessed by segmenting the thalamus based on connectivity to the frontal, parietal, temporal and occipital cortices and determining the volumes and mean diffusivity of the thalamic projections. Linear regression analysis was performed to test the relationship between increasing age and (i) normalised thalamic volume, (ii) whole thalamus diffusion measures, (iii) mean diffusivity (MD) of the thalamo-cortical projections, and (iv) volumes of the thalamo-cortical projections. We also assessed thalamic shape change using vertex analysis. We observed a significant reduction in the volume and a significant increase in MD of the whole thalamus with increasing age. The volume of the thalamo-frontal projections decreased significantly with increasing age, however there was no significant relationship between the volumes of the thalamo-cortical projections to the parietal, temporal, and occipital cortex and age. Thalamic shape analysis showed that the greatest shape change was in the anterior thalamus, incorporating regions containing the anterior nucleus, the ventroanterior nucleus and the dorsomedial nucleus. To explore these results further we studied two additional groups of subjects (a younger and an older aged group, n=20), which showed that the volume of the thalamo-frontal projections was correlated to executive functions scores, as assessed by the Stroop test. These data suggest that atrophy of the frontal thalamo-cortical unit may explain, at least in part, disorders of attention, working memory and executive function associated with increasing age.

Intracranial hemorrhage in neonates: A review of etiologies, patterns and predicted clinical outcomes.

Intracranial hemorrhage (ICH) in neonates often results in devastating neurodevelopmental outcomes as the neonatal period is a critical window for brain development. The neurodevelopmental outcomes in neonates with ICH are determined by the maturity of the brain, the location and extent of the hemorrhage, the specific underlying etiology and the presence of other concomitant disorders. Neonatal ICH may result from various inherited and acquired disorders. We classify the etiologies of neonatal ICH into eight main categories: (1) Hemorrhagic stroke including large focal hematoma, (2) Prematurity-related hemorrhage, (3) Bleeding diathesis, (4) Genetic causes, (5) Infection, (6) Trauma-related hemorrhage, (7) Tumor-related hemorrhage and (8) Vascular malformations. Illustrative cases showing various imaging patterns that can be helpful to predict clinical outcomes will be highlighted. Potential mimics of ICH in the neonatal period are also reviewed.