MR myelography of sacral meningeal cysts

Purpose: To describe the findings of sacral meningeal cysts (SMCs) on MR my elography and assess its Value for the diagnosis of SMCs. Material and Methods: We evaluated the MR images and MR myelograms obtained from 10 patients with SMC. MR myelograms were obtained using a 2D or 3D si ngle-shot fast spin-echo sequence. In 5 patients, X-ray myelograms and post myelographic CT images were compared with the MR myelograms. Results: A total of 33 SMCs were diagnosed within the spinal canal and/or s acral foramen. MR myelograms clearly revealed each cyst as a well-defined m ass showing hyperintensity (10 cysts) or isointensity (23 cysts) compared t o cerebrospinal fluid. MR myelograms demonstrated SMCs better than X-ray my elograms and postmyelographic CT images in 3 of the 5 patients. Conclusion: MR myelography can be an adjunct to conventional imaging techni ques when surgical treatment is indicated, because it can precisely delinea te the extent of SMCs.