Atypical presentation of atypical teratoid rhabdoid tumor in a child.

Atypical Teratoid Rhabdoid Tumor (ATRT) is a rare malignant intracranial neoplasm more commonly diagnosed in young children. The authors report the case of an 11-year-old boy with a long standing history of slowly progressive weight loss, fatigue, and weakness over 1.5 years whose magnetic resonance imaging revealed a large heterogeneous enhancing dorsally exophytic lower brainstem mass. Examination revealed extreme cachexia, gaze-evoked nystagmus, dysphagia, dysarthria, bilateral dysmetria, and global weakness without ambulation. The protracted history and neuroimaging features were most suggestive of a low grade glioma. However, pathology revealed a hypercellular tumor with large hyperchromatic nucleoli and loss of INI-1 staining on immunohistochemistry consistent with a diagnosis of an ATRT. The child died shortly after surgery due to complications from his brainstem infiltrative disease. This case illustrates the diverse presentation of ATRT in childhood that can clinically and radiographically mimic that of low grade glioma.

Distinguishing 3 classes of corpus callosal abnormalities in consanguineous families.

OBJECTIVE: We sought to create a classification system for pediatric corpus callosal abnormalities (CCA) based upon midline sagittal brain MRI. We used the term CCA for patients with structural variants of the corpus callosum, excluding patients with interhemispheric cyst variant or pure dysplasia without hypoplasia. Currently, no system exists for nonsyndromic forms of CCA, and attempts to create such a system have been hampered by highly variable morphology in patients with sporadic CCA. We reasoned that any useful strategy should classify affected family members within the same type, and that phenotypic variability should be minimized in patients with recessive disease. METHODS: We focused recruitment toward multiplex consanguineous families, ascertained 30 patients from 19 consanguineous families, and analyzed clinical features together with brain imaging. RESULTS: We identified 3 major CCA classes, including hypoplasia, hypoplasia with dysplasia, and complete agenesis. Affected individuals within a given multiplex family usually displayed the same variant of the class of abnormality and they always displayed the same class of abnormality within each family, or they displayed complete agenesis. The system was validated among a second cohort of 10 sporadic patients with CCA. CONCLUSIONS: The data suggest that complete agenesis may be a common end-phenotype, and implicate multiple overlapping pathways in the etiology of CCA.

Malformations of cortical development with balloon cells: clinical and radiologic correlates.

BACKGROUND: Balloon cells are a key feature of tuberous sclerosis (TS) but are also seen in focal cortical dysplasia (FCD). The authors compare the clinical and MRI characteristics in children with medically refractory localization-related epilepsy who were found to have balloon cells on histology after cortical resections. METHODS: A retrospective review of clinical and MRI data in cases ascertained from a search of pathology records from 1990 until 2000 for those with a diagnosis of FCD or TS. Seventeen patients were identified with malformations of cortical development with balloon cells on histology. Seven had clinical diagnosis of TS and the remaining 10, FCD with balloon cells (FCDBC). RESULTS: Seventy percent of patients with FCDBC (mean follow-up 3.3 years) and 33% of patients with TS (mean follow-up 5.1 years) are seizure free after surgery. There was agreement between the diagnosis based on preoperative MR imaging and on histology in 60% of patients with FCDBC and 71% of patients with TS. Myelin depletion and calcification were noted more frequently in patients with TS. CONCLUSIONS: No significant differences were noted between patients with refractory epilepsy caused by TS or FCDBC. There was a trend toward better postoperative seizure control in the FCDBC group. These two conditions are difficult to distinguish on the basis of MR and histologic appearances. The authors conclude that FCDBC likely represents a phenotypic variation of TS, and as such, all patients with balloon cell dysplasias should be carefully screened for other features of TS to enable appropriate genetic counseling.

Multiple risk factors in neonatal sinovenous thrombosis.

The etiology of neonatal sinovenous thrombosis is poorly understood. The authors report the risk factors and radiologic features of neonatal sinovenous thrombosis seen over an 11-year period. Of 30 patients, 29% received extracorporeal membrane oxygenation treatment, and 23% had congenital heart disease. Genetic thrombophilias were present in four of the seven infants tested. Eighteen neonates had multiple maternal, neonatal, perinatal, or prothrombotic complications. Sinovenous thrombosis was often accompanied by infarction (50%) or intraventricular hemorrhage (33%).