[Vertebral osteoblastoma and scoliosis. Two cases report]. / Ostéoblastome vertébral et scoliose. A propos de deux cas.

We report two cases of spinal osteoblastoma in two boys aged 16 and 19 years. The lesion was disclosed by scoliosis with signs of thoracic and lumbar neurological compression. The diagnosis was provided by the CT scan and magnetic resonance imaging and was confirmed by the histology study of the surgical specimen. Involvement of the vertebral column has been estimated to range from 30 to 40% for these rare tumors that account for less than 1% of all bone tumors. Localization on the convex aspect of scoliosis is rare. CT-scan provides an analysis of the tumor components and clearly demonstrates intraspinal extension. MRI is superior in visualizing neurological compression. In our experience, function outcome has been favorable after surgical decompression.

[Epidural hydatid cyst of the posterior fossa]. / Kyste hydatique extradural de la fosse cérébrale postérieure.

We report a case of epidural hydatid cyst in the posterior fossa in a 5-year-old child. The disease was revealed by raised intracranial pressure with torticollis. The diagnosis was based on the brain CT scan and MRI, and confirmed surgically. The course was uneventful. Cranial epidural hydatid cysts are very rare: only 18 cases have been reported previously in the literature.

[Intracranial granuloma: a rare complication of ventricular derivation. Case report]. / Granulome intracrânien: complication rare de la dérivation ventriculaire. A propos d'un cas.

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.

[Spontaneous rupture of an intracerebral dermoid cyst]. / Rupture spontanée du kyste dermoïde en intracérébral.

Dermoid and epidermoid cysts are rare benign tumors arising from ectopic epiblastic inclusions. Dermoid cyst accounts for 0.4 to 1.5% of all tumors. We report the case of a 43-year-old man, who presented with a 6-month history of disturbances of balance and behavioral disorders. X-ray showed two fat-fluid levels in the ventricles. CT scan showed a left frontal mass with fat density, communicating with the left frontal horn. Histological examination after surgical excision confirmed the diagnosis of dermoid cyst. The diagnosis of ruptured intracranial dermoid cyst is based on the finding of an intraventricular and/or subarachnoid space fat-fluid level. MRI and CT scan facilitates the diagnosis of ruptured intracranial dermoid.