Arachnoid cyst of the fourth ventricle and "arrested" hydrocephalus.
D001099:Arachnoid / Q000473:pathology / Q000601:surgery*; D002552:Cerebral Ventricles / Q000601:surgery*; D014695:Cerebral Ventriculography; D002648:Child; D003560:Cysts / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D006801:Humans; D006849:Hydrocephalus / Q000601:surgery*; D008297:Male; D014057:Tomography, X-Ray Computed