title: Epidermoid tumor of the fourth ventricle: use of metrizamide-computed tomography.
abstract: This report describes two cases of epidermoid tumor of the fourth ventricle diagnosed with metrizamide computed tomography. They both presented as a low-density lesion in the region of the fourth ventricle on computed tomography. They did not show any enhancement after intravenous injection of contrast medium and had no hydrocephalus. Metrizamide-enhanced computed tomography demonstrated the irregular fourth-ventricular filling defect characteristic of epidermoid tumors.
mesh_terms: D000328:Adult; D001927:Brain Diseases / Q000000981:diagnostic imaging; D002552:Cerebral Ventricles; D014695:Cerebral Ventriculography; D002781:Cholesteatoma / Q000000981:diagnostic imaging*; D006801:Humans; D007278:Injections, Spinal; D008297:Male; D008793:Metrizamide / Q000008:administration & dosage; D011856:Radiographic Image Enhancement; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D008793:Metrizamide