Noritoshi Shirozu1, Takato Morioka2, Satoshi Inoha1, Naoyuki Imamoto1, Takakazu Sasaguri3. 1. Department of Neurosurgery, Japan Community Health Care Organization (JCHO), Kyushu Hospital, Kitakyushu, Japan. 2. Department of Neurosurgery, Fukuoka Children's Hospital, 5-1-1 Kashii-teriha, Higashi-ku, Fukuoka, 813-0017, Japan. takato@ns.med.kyushu-u.ac.jp. 3. Department of Pathology, Japan Community Health Care Organization (JCHO), Kyushu Hospital, Kitakyushu, Japan.
Abstract
BACKGROUND: A retained medullary cord (RMC) is a rare closed spinal dysraphism with a robust elongated neural structure continuous from the conus and extending to the dural cul-de-sac. Four cases of RMC extending down to the base of an associated subcutaneous meningocele at the sacral level have been reported. CLINICAL PRESENTATION: We report an additional case of RMC, in whom serial MRI examination revealed an enlargement of the meningocele associated with RMC over a 3-month period between 8 and 11 months of age, when he began to stand. At the age of 12 months, untethering of the cord was performed. Histologically, the presence of ependyma-lined central canals in the dense neuroglial cores was noted in all cord-like structures in the intradural and intrameningocele sacs and at the attachment to the meningocele. CONCLUSION: It is conceivable that the hydrodynamic pressure with standing position and the check valve phenomenon were involved in meningocele enlargement. We should be mindful of these potential morphological changes.
BACKGROUND: A retained medullary cord (RMC) is a rare closed spinal dysraphism with a robust elongated neural structure continuous from the conus and extending to the dural cul-de-sac. Four cases of RMC extending down to the base of an associated subcutaneous meningocele at the sacral level have been reported. CLINICAL PRESENTATION: We report an additional case of RMC, in whom serial MRI examination revealed an enlargement of the meningocele associated with RMC over a 3-month period between 8 and 11 months of age, when he began to stand. At the age of 12 months, untethering of the cord was performed. Histologically, the presence of ependyma-lined central canals in the dense neuroglial cores was noted in all cord-like structures in the intradural and intrameningocele sacs and at the attachment to the meningocele. CONCLUSION: It is conceivable that the hydrodynamic pressure with standing position and the check valve phenomenon were involved in meningocele enlargement. We should be mindful of these potential morphological changes.