RESUMO
We experienced a rare case of sacral meningeal cyst so called sacral perineurial cyst(Tarlov cyst). A 15 years old girl was admitted to the hospital because of sudden severe low back pain and Lt. sciatica for about one week. We performed delayed myelography and spinal computeized tomographic myelography(C.T.M) for differential diagnosis. Delayed filling of contrast media in the cyst was significant in diagnosis of sacral meningeal cyst type II. Laminectomy of sacrum(S1) was performed for partial excision of cystic wall and plastic suture. Operative finding was typical sacral perineurial cyst(Tarlov cyst) which was recently clssified as sacral meningeal cyst type II. The classification of spinal meningeal cysts in the literature was indistinct and confused. We also agree with Nabors et. al, in current classificcation of spinal meningeal cysts, in which the spinal meningeal cysts, in which the spinal meningeal cysts were divided into 3 groups as extradural spinal Mcs Type I(Diverticulum), Type II(perineurial cyst), intradural spinal Mcs(arachnoid cyst).