Anatomical Venous Variants in Children with Cerebral Sinovenous Thrombosis

Background and Purpose - Literature is sparse on the frequency and significance of anatomical venous variants (AVVs) in pediatric cerebral sinovenous thrombosis (CSVT). Methods - We retrospectively reviewed children with CSVT and controls undergoing computed tomography/magnetic resonance venography from January 2008 to 2014. Clinical features examined included raised intracranial pressure, risk factors, and treatment. Radiological features examined included CSVT location, presence and type of AVVs, hemorrhagic venous infarction, and venous collateralization. Clinical outcome was measured by the pediatric stroke outcome measure and radiological outcome by thrombus recanalization. Results - Fifty-one children with CSVT were identified. Twenty-two (43%) had AVVs at presentation. Nineteen (86%) had hypoplasia/absence of major dural sinus, 5 (23%) had persistent fetal structures, 3 (14%) had duplications/fenestrations, and 1 (5%) had disconnected superficial and deep venous systems. Controls had a slightly higher but nonsignificant prevalence 26 (51%) of AVVs. No significant clinical and radiological differences were observed between children with CSVT and AVVs compared with those with typical venous anatomy. Conclusions - AVVs are seen in many children with and without CSVT and do not seem to alter the presentation or clinical course. The influence of these variations on the brain\u27s ability to tolerate venous congestion because of thrombosis merits further study

Chromosome 12p Deletion Spanning the GRIN2B Gene Presenting With a Neurodevelopmental Phenotype

The GRIN2B (glutamate receptor, ionotropic, N-methyl- d -aspartate 2B) gene, located in the short arm of chromosome 12, encoding the NR2B subunit of the N-methyl-D-aspartate receptor, has recently been recognized to play an important role in corticogenesis and brain plasticity. Deletions in the short arm of chromosome 12 are rare. Hemizygous loss of function of the GRIN2B gene results in developmental delay, whereas gain of function leads to epilepsy, and infantile spasms in particular. In addition, GRIN2B variants have been associated with autism spectrum disorder and schizophrenia. Here the authors report a child with global developmental delay, autistic behavioural features, central hypotonia, dysmorphic features and isolated congenital anomalies of the fingers and toes, and a de novo heterozygous deletion in chromosome locus 12p13.2-p13.1, involving loss of several genes, including GRIN2B . This report and our review of the literature help clarify the distinct phenotypes associated with loss or gain of GRIN2B function