[Intracranial granuloma: a rare complication of ventricular derivation. Case report]

We report an unusual case of cerebral granuloma secondary to ventriculoperitonal shunt. A 17 year-old patient presented with choreoathetoid movements of the left upper limb five years after a ventriculoperitoneal shunt and cerebellar pilocytic astrocytoma excision procedure. MR imaging showed mass lesion in right basal ganglia area surrounding ventricular catheter which seems to be neoplastic. Stereotactic biopsy of the lesion with histologic study revealed a granuloma. Ventricular catheter was removed and patient improved clinically and lesion disappeared completely on MRI control. At literature review, we found only 4 similar cases. Clinical and radiological findings (CT scan and IRM) are described as well as pathogenic mechanism involved. Therapeutic procedure should be limited to catheter removal without granuloma excision.