5North RB, Kidd DH, Wang H. Occult bilateral anterivr and intrasacral meningeal and perineurial cysts: case report and review of the literature.Neurosugery 1990;27:981.
6Davis S W Levy L M, Bihan D J,et al.Sacral meningeal cycts:evaluation with MR imagimg[J].Radiology,1984,187(2):445.
7Plews J L,Jacobson.Sciatica caused by sacral-root cysts[J]. LaneL,1970,17:799.
