Supine myelography and the septum posticum.
D000293:Adolescent; D000328:Adult; D000368:Aged; D002102:Cadaver; D002648:Child; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008297:Male; D008578:Meninges / Q000000981:diagnostic imaging*; D008722:Methods; D008875:Middle Aged; D009192:Myelography; D013122:Spinal Diseases / Q000000981:diagnostic imaging; D013346:Subarachnoid Space / Q000000981:diagnostic imaging*