Cystic dilation of a ventriculus terminalis. Case report and review of the literature.

The ventriculus terminalis (VT) is a small ependyma-lined cavity within the conus medullaris that is in direct continuity with the central canal of the spinal cord. Cystic dilatation of the ventriculus terminalis on its own is an extremely rare pathological event in adults whose pathogenesis is uncertain. VT has been described in children as a normal developmental phenomenon. These lesions are often diagnosed incidentally during imaging and are in most cases asymptomatic, especially in children. Symptomatic dilatation of VT in adults is a rare condition with 61cases being reported to date. Symptomatic dilatation of VT in children has not been reported till now. We present a 5 year-old-boy with a sphincteric and walking disorder. The patient was assessed by clinical, electrophysiological and urodynamic investigations as well as magnetic resonance imaging (MRI) of the lumbar-sacral segment with and without gadolinium enhancement. Lumbar-sacral MRI demonstrated the presence of a cystic lesion containing cerebrospinal fluid (CSF), which did not enhance after gadolinium, compatible with the diagnosis of the ventriculus terminalis dilation.The patient underwent laminectomy and the cyst wall was fenestrated with a midline myelotomy. In 6-month of follow-up, urinary problems and gait disturbance improved.