Third ventricular choroid plexus papilloma with psychosis. Case report.

This 9-year-old boy with a history of behavioral problems and worsening psychosis responded initially to treatment with haloperidol. However, a magnetic resonance image obtained as part of his psychiatric evaluation revealed an anterior third ventricle tumor and mild-to-moderate hydrocephalus. The resected tumor was found on pathological examination to be a choroid plexus papilloma. The patient had an uneventful postoperative course and remained free of psychosis or mood disorder at 1-year follow-up examination.

Meningioma of the fourth ventricle presenting with intermittent behaviour disorders: a case report and review of the literature.

Intraventricular meningiomas are rare, representing 0.5-5% of all intracranial meningiomas. They arise mostly within the lateral ventricles and more rarely in the third ventricle. Meningiomas of the fourth ventricle are exceptional. They are clearly defined as meningiomas arising from the choroid plexus and lying strictly within the fourth ventricle. We report a 76 year old male patient presenting with a 2-week history of headache and cognitive disorders with agitation and restlessness particularly exacerbated at night or when lying down. CT scan and MR imaging showed a contrast-enhancing lesion located purely within the whole fourth ventricle, with slight ventricular enlargement. At surgery, we totally removed a well-vascularised, greyish encapsulated mass attached to the choroid plexus. Pathological examination revealed a WHO grade I fibroblastic meningioma. We reviewed the literature concerning this unusual meningioma location.

Posterior fossa lesions associated with neuropsychiatric symptomatology.

We reviewed 7 cases with posterior fossa structural abnormalities (3 tumors, 2 megacisterna magna and 2 Dandy-Walker syndrome) presenting with neuropsychiatric symptomatology. Derangement in the balance of dopamine, serotonin and noradrenergic networks has been implicated in the pathogenesis of schizophrenia, affective and even personality disorders. Disruption of the cerebellar output to mesial dopaminergic areas, locus coeruleus and raphe nuclei, or deafferentation of the thalamolimbic circuits by a cerebellar lesion may lead to behavioral changes. Seven patients (pts) (comprising 4 men and 3 women with mean age 22 years) were diagnosed as suffering from psychosis (2 pts), major depression (1 pt), personality disorders (2 pts) and somatoform disorders (2 pts) (DSM-IV criteria). Brain CT scan (7 pts) and MRI (4 pts) revealed tumors of the posterior fossa (2 pts), megacisterna magna (2 pts) and Dandy-Walker variant (2 pts). In one patient a IVth ventricle tumor was removed in childhood.