Eight patients with posttraumatic intermittent rhinoliquorrhea were examined in the dry non-drop period, seven of them with CT metrizamide cisternography. The evidence of fracture of the skull base in combination with protruding soft tissues into the sinuses, a local deformity of basal sulci, and pooling of contrast medium in a dural pouch or herniated soft tissue plug will localize the site of leakage. There is no need for special maneuvers such as raising the intracranial pressure in order to initiate flow of the cerebrospinal fluid. Criteria for localizing the leakage are discussed.