Evaluation of MR cisternography in diagnosis of cerebrospinal fluid fistula.
OBJECTIVE
To study the clinical usefulness and sensitivity of MR cisternography as noninvasive study in the diagnosis of CSF fistula in patients with clinical diagnosis CSF rhinorrhea or otorrhea.


METHODS
Thirty-five patients with clinically diagnosed CSF leakage were examined for site of dural tear with MR cisternography with additional plain high-resolution CT in some cases from Jan. 1999 to Dec.2002. The MR imaging technique was performed as a heavily T2 weighted fast spin echo study with fat suppression in axial, coronal and sagittal projections. Criteria for positive results were demonstrable fistular tract connecting subarachnoid space to paranasal sinus/petrous bone, and/or dural discontinuity, and/or bone defect with pneumocephalus, and/or presence of brain herniation. Eighteen of the patients subsequently had exploratory surgery for fistula. Sensitivity analysis of the surgical results was compared with the findings at MR cisternography.


RESULTS
MR cisternography showed significant correlation with surgical findings with sensitivity of 89%. Additional high resolution CT were complete agreement with site of fistular tract. The pathogenesis of CSF leakage was related to trauma (86%). The commonly found dural/bony defect and location of connecting fislular tract were cribriform plate and ethmoid sinus of 58%, 55% respectively.


CONCLUSIONS
In the presence of clinically diagnosed CSF leakage, the combination of MR cisternography and plain high-resolution CT are highly accurate in locating the site and extent of CSF fistula and should be considered a viable noninvasive alternative to CT cisternography and Tc-99m-DTPA cisternography.
Tuntiyatorn
Lojana
L
Department of Radiology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Laothammatas
Jiraporn
J
D000293:Adolescent; D000328:Adult; D002558:Cerebrospinal Fluid Otorrhea / Q000175:diagnosis* / Q000601:surgery; D002559:Cerebrospinal Fluid Rhinorrhea / Q000175:diagnosis* / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D005260:Female; D005402:Fistula / Q000175:diagnosis* / Q000601:surgery; D049671:History, 18th Century; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity