[Experiences with assessment of frontobasal defects, a diagnostic concept]

Cerebrospinal fluid (CSF) rhinorrhea presents not only a therapeutic challenge, but a diagnostic challenge as well. This is especially true in the case of atraumatic spontaneous leakage, which is often only minimal in quantity and can occur intermittently. The purpose of this paper is to compare the current methods of evaluation of CSF Rhinorrhea (beta 2-Transferrin assay, high resolution computed tomography [HRCT], and computotomographic cisternography [CTC]) and develop a diagnostic protocol.

A retrospective analysis was performed of 61 patients who underwent operation for CSF rhinorrhea between 1988 and 1996 comparing the method of preoperative diagnosis and intraoperative findings.

beta 2-transferrin-determination in the nasal discharge had a sensitivity of 79% (33/42), HRCT correctly identified the defect in 84% (48/57) of cases, and CTC correctly localized the pathology in 72% (18/25) of the patients.

The sensitivity of each CSF rhinorrhea diagnosis method is less than 90%. It is our opinion that with the current level of technology a combined approach is optimal with two or more of the above studies. A diagnosis scheme is presented to manage step by step this challenging and potentially lethal problem.