Thoracic spinal metastasis from unexpected cerebellar medulloblastoma: the value of MRI

Cauda equina syndrome as the initial presenting clinical feature of medulloblastoma: a case report

INTRODUCTION

Medulloblastoma is one of the most common pediatric brain malignancies. The usual presenting clinical features are related to posterior fossa syndrome or/and hydrocephalus. Cauda equina syndrome is a very rare presentation for this disease.

CASE PRESENTATION

We describe the case of a three-year-old boy with cauda equina syndrome as the initial presenting clinical feature for medulloblastoma. He was initially diagnosed as having a spinal tumor by magnetic resonance imaging scan. Subsequently, a cranial magnetic resonance imaging scan revealed a posterior fossa tumor with features of dissemination. He had substantial improvement after treatment. This case report is complemented by a literature review related to this unusual presentation.

CONCLUSIONS

Medulloblastoma primarily presenting with cauda equina syndrome is very rare. However, spinal drop metastasis should be considered in the pediatric age group to avoid suboptimal management.

Magnetic resonance imaging of the brain and spine

The efficacy of magnetic resonance imaging (MRI) in the diagnosis of diseases of the central nervous system is reviewed. MRI, computed tomography (CT) and certain radionuclide studies are compared in the evaluation of intracranial tumours, cerebral vascular disease, multiple sclerosis and other white matter diseases, dementia, head injury, infection, epilepsy, spinal lesions and in paediatric central nervous system disorders. The measurement of cerebrospinal fluid volumes and dynamics by MRI is discussed. MRI most clearly has advantages where CT is degraded by bone hardening and streak artefacts (spine, skull base, posterior and temporal fossa, sella and parasellar regions) and in diseases in which the X-ray attenuation of the suspected lesion differs little from normal parenchyma (paediatric brain disorders, demyelination and dysmyelination, early oedema associated with infarction, infection or low-grade infiltrating neoplasm, subacute and chronic haemorrhage and lesions in the spinal subarachnoid space and cord). Elsewhere MRI and CT should be seen as complementary rather than competitive methods of imaging. In spite of an absence of information about the contribution of MRI to management decisions and a lack of rigorous, prospective controlled trials, MRI will play an increasing role in the diagnosis of diseases of the central nervous system.