Primary diffuse leptomeningeal gliomatosis: unusual MRI with non-enhancingnodular lesions on the cerebellar surface and spinal leptomeningeal enhancement

A 28 year old man presented with a 1 month history of symptoms of intracran ial hypertension. Examination showed bilateral papilloedema and meningeal s igns. Magnetic resonance imaging showed nodular lesions on the cerebellar a nd pontine surface and thickening of the thoracic spinal leptomeninges. Thr oughout the course of the disease, contrast enhancement was detected in the spinal leptomeninges but not intracranially. Primary diffuse leptomeningea l gliomatosis (PDLG) was diagnosed by biopsy and later confirmed on necrops y. The present case is remarkable for the nodular superficial cerebellar le sions and the absence of intracranial contrast enhancement of the leptomeni nges.