Computed tomography and cerebrospinal fluid leak.

Cerebrospinal fluid (CSF) rhinorrhea is a serious condition which if untreated may lead to meningitis. Detection of the leak site at surgery may be difficult without prior accurate radiological localization of the leak and at times repeat operation has been required. Clinical and radiological localization of the leak is not always easy and many different tests have been tried. Prior to computed tomography (CT), the most common combination of radiological tests were plain films and tomograms of the skull and CSF isotope studies. Although CT scanning may be helpful in assessing a patient with CSF rhinorrhea, it is most effective when combined with intrathecal Metrizamide. The combination of Metrizamide and CT was first reported in 1977 and several case reports and small series of cases have since been reported. The purpose of this article is to review the value of CT especially when used in combination with Metrizamide in the patient with CSF leak and also to discuss the technique of the combined study and to show its value with illustrative cases.