Nerve root infiltration of the first sacral root with MRI guidance

The purpose of this clinical trial was to describe the methodology and eval uate the accuracy of optical tracking-based magnetic resonance (MR)-guided infiltration of the first sacral (81) root. Thirty-five infiltrations were performed on 34 patients with a 0.23-T open C-arm magnet installed in a ful ly equipped operation room with large-screen (36 inches) display and optica l navigator utilizing infrared passive tracking. T1 and T2 fast spin-echo ( PSE) images were used for localizing the target and fast field echo for mon itoring the procedure. Saline as contrast agent in single-shot (SS)FSE imag es gave sufficient contrast-to-noise ratio. Twenty-four patients had unoper ated L5/S1 disc herniation, and 10 had 81 root irritation after failed back surgery. Needle placement was successful in 97% of the cases, and no compl ications occurred. Outcome was evaluated 1-6 months (mean 2.2 months) after the procedure and was comparable to that of other studies using fluoroscop y or computed tomography guidance. MR-guided placement of the needle is an accurate technique for first sacral root infiltration. J. Magn. Reson. Imag ing 2000; 12:556-561. (C) 2000 Wiley-Lies, Inc.