Imaging of CNS manifestations of tuberous sclerosis in children

Tuberous sclerosis (TS) is a frequent phakomatosis, with autosomal dominant transmission. The diagnosis relies on a list of criteria (2 major criteria or 1 major criterion and 2 minor criteria). Brain MRI is very important for diagnosis, already showing the major signs during fetal life: subependymal nodules, tubers and giant cell astrocytomas. In childhood, FLAIR sequences are the more interesting while in fetuses, neonates and infants T1 sequences are required because of the myelination process.     

MRI of the brain in the evaluation of children with developmental delay

PURPOSE: To analyze the diagnostic value of MRI in children with developmental delay. Materials and Methods. From 1991 to 1997, 224 examinations were performed. Retrospective analysis of clinical findings and diagnostic yield was carried out. RESULTS: MRI was abnormal in 109 cases. It never resulted in any patient care modification. 55 malformations, 12 cases of cerebral atrophy, 7 cases of white matter disease and 2 patients with phakomatose were identified. Myelination delay (26 cases), increased signal of posterior white matter on T2-weighted images (9 cases) or widened Virchow-Robin spaces (3 cases) were frequently encountered, but it remained unclear whether they represented normal variants or true abnormalities. Post ischemic lesions were identified in 10 cases. Frequency of abnormal studies was significantly lower in children with developmental delay and behavioral disorders than in patients with other clinical presentation. CONCLUSION: Diagnostic yield of cerebral MRI can justify its performance by comparison to other imaging modalities. It should be correlated with other investigations performed in a specialized unit. Its main interest is for classification and research. Risk of sedation or anesthesia should also be taken in account. Risk can be lowered using adequately equipped MR units and organizing procedures in collaboration with anesthesiologists.     

Prenatal diagnosis of isolated posterior fossa anomalies: attempt at a simplified approach

The authors suggest, after some embryological, anatomical and nosological reviews, a simplified approach mainly based on the appearance of the pons, cerebellar hemispheres and vermis, independently from an associated cystic dilatation of the posterior fossa. Pontocerebellar hypoplasias and partial or total vermian agenesis are detailed because they can be diagnosed with a prenatal MRI. This classification based on our experience and on the literature data should be of value to evaluate the neurological prognosis.     

The intervertebral disk: a landmark for spinal diseases in children

The aim of this paper is to describe the diagnostic value of the different radiological modifications of the intervertebral disk in children. Usual disk modifications include: disk-space narrowing; disk space enlargement; intervertebral disk calcifications; intervertebral disc prolapse; and signal modification in MRI. The gamuts (which are provided in the paper) of these different images must take into account the association with bone changes and the possibility of several disks' involvement. Calcifications are usually related to benign disorders.     

Ependymoma in childhood: prognostic factors,extent of surgery,and adjuvant therapy

OBJECT: The aim of this study was to investigate the effect of patient-related factors, extent of surgery, and adjuvant therapy on survival in children presenting with intracranial ependymoma. METHODS: Between 1980 and 1999, 83 children (mean age 36 months) underwent surgery for intracranial ependymomas. Complete resection, verified on postoperative computerized tomography scans, was achieved in 73%. Adjuvant therapy modalities have changed over the years: before 1990 all patients received radiotherapy, whereas after 1990 the children younger than 3 years of age and later those younger than 5 years of age were treated first with chemotherapy and received radiotherapy only after their first tumor recurrence. The follow-up period averaged 70 +/- 49 months. CONCLUSIONS: Overall survival, intraoperative deaths excluded, was 73 +/- 11% and 51 +/- 14% at 5 and 10 years, respectively. The event-free survival rate at 5 and 10 years was 48 +/- 12% and 46 +/- 12%, respectively. Most of the events were local recurrences. Despite multiple reinterventions, the overall survival rate in this group dropped to 14%. On univariate analysis, the only significant prognostic factors were complete resection and radiotherapy. Both of these factors combined increased the 5- and 10-year survival rates to 93 and 75%, respectively. Age of the patients was not a statistically independent prognostic factor. The patients in the chemotherapy group did not fare as well as those in the radiotherapy group. A subgroup (36%) within the chemotherapy group, however, survived tumor free after a mean follow-up period of 67 months. It is not clear whether this subgroup either responded well to chemotherapy or needed no adjuvant therapy. Further research is warranted to answer this question.