MR CISTERNOGRAPHY - A NEW METHOD FOR THE DIAGNOSIS OF CSF FISTULAS

The aim of this study was to compare a new MRI method for detecting th e existence of cerebrospinal fluid (CSF) fistulae, i. e. MR cisternogr aphy, with CT cisternography. In a prospective study, 30 patients with post-traumatic CSF fistulae were examined. The MR examinations were p erformed with a 1.0-T whole-body MR system, using two T2-weighted seq uences, a 3D PSIF (time-inversed fast imaging with steady-state preces sion, FISP) and a 3D constructive interference steady-state (CISS) seq uence. The results of MRI and CT cisternography were compared with the surgical findings. The sensitivity in detecting CSF fistulae with MR cisternography (PSIF: 89.9 %; CISS: 93.6 %) was higher than with CT ci sternography (72,3 %). The sensitivity of CT cisternography at detecti ng CSF fistulae in patients with a size of dural lesion less than 2 mm or in patients with multiple dural lesions is significantly lower com pared with the MR method. Although the localization of CSF fistulae al ways proved possible with MR cisternography, this could only be accomp lished wih CT in 70 % of cases. The MR cisternography technique is a n ew examination method with a higher sensitivity for the detection of C SF fistulae than CT cisternography. The CISS technique is superior com pared with PSIF and should be used in patients with high-flow CSF fist ulas.