Background and purpose: This study investigated the role of CT as an early predictor of outcome prognosis after glue embolization of spinal dural arteriovenous fistulas (SDAVF).
Methods: Over a 13-year period, 26 patients underwent glue embolization of SDAVF and were retrospectively reviewed. Immediately after embolization, each patient had CT evaluation of cast position. Mean follow-up angiography was 23.4 months (range, 1-87 months; median, 21 months). Both MR images and clinical data (e.g., gait and micturition disabilities according to the Aminoff and Logue disability scale, deep and superficial sensitivity) were analyzed, with a mean follow-up of 37.7 months (range, 12-98 months; median, 28 months). Data were tested by univariate analysis by using Fisher's exact test and the Kruskall Wallis test, depending on the order of the qualitative variables.
Results: Glue was found in the dura mater on CT in 19 (73%) patients. None of these patients had a recanalized fistula on angiography, and the clinical status of all of them improved. Glue was observed in or proximal to the foramen on CT in seven (27%) patients. In five of them, the fistula was recanalized within a mean period of 9 months (range, 3-24 months; median, 6 months) and their clinical status worsened. All five required surgical treatment. On angiography, the absence of fistula recanalization was observed in 21 (81%) patients and correlated with improvements in gait (P = .016), sensitivity (P = .030), and micturition (P = .080). It also correlated with a decrease in the extent of the abnormally high intramedullary T2 signal intensity (P = .002), a decrease in spinal cord diameter (P = .017), and the resolution of prominent perimedullary vessels (P < .001). The presence of glue within the dura mater on CT correlated with the absence of fistula recanalization (P = .045) and with overall improvement in clinical status, including gait and/or sensitivity and/or micturition (P = .042).
Conclusion: CT evaluation of embolization cast position immediately after embolization may constitute an early and reliable tool for predicting permanent fistula occlusion and the prognosis for outcome.