Dynamic Lumbosacral Magnetic Resonance Imaging in a Dog with Tethered Cord Syndrome with a Tight Filum Terminale
Dynamic Lumbosacral Magnetic Resonance Imaging in a Dog with Tethered Cord Syndrome with a Tight Filum Terminale
复制标题
DOI：
10.3389/fvets.2017.00134
复制
发表时间：
2017-08-18
影响因子：
3.2
通讯作者：
Neilson, David M.
中科院分区：
文献类型：
--
作者：
De Decker, Steven;Watts, Vicky;Neilson, David M.
对一只 1 岁零 11 个月大的英国可卡犬进行了右骨盆肢体进行性跛行和尿失禁的临床症状评估。神经学检查提示病变位于 L4-S3 脊髓节段。对狗进行的磁共振成像（MRI）检查没有发现异常，该狗处于背卧位，髋部处于中立位，并且髓圆锥终止于L7椎体的中间。髋部在伸展和弯曲位置的 MRI 分别显示，圆锥在颅侧和尾侧方向的位移最小。与中立位置的图像类似，无论是伸展位置还是弯曲位置，髓圆锥都终止于 L7 椎体的中间。相比之下，对另一只英国可卡犬进行的髋部处于中立位、伸展位和弯曲位的 MRI 显示，髋部伸展时，髓圆锥有明显的颅侧移位，髋部弯曲时，尾部移位。进行了标准的背侧腰骶椎板切除术。椎管的目视检查显示脊髓圆锥尾部牵引过度。切开终丝远端后，髓圆锥恢复到更靠近颅骨的位置。术后 4 周的神经系统检查显示临床改善。术后2、4、7和12个月的神经系统检查未发现任何异常，狗被认为临床正常。终丝过紧的脊髓栓系综合征是一种非常罕见的先天性异常，其特征是终丝异常短且无弹性。因此，这种疾病与脊髓尾部异常牵引和椎管内神经结构的生理性头尾运动减少有关。虽然需要进一步的研究来评估和量化神经正常狗的脊髓和圆锥的生理性头尾运动，但本报告的结果建议进一步探索动态 MRI，以证明患有终丝紧绷的脊髓栓系综合征的狗的圆锥头尾位移减少。
A 1-year and 11-month- old English Cocker Spaniel was evaluated for clinical signs of progressive right pelvic limb lameness and urinary incontinence. Neurological examination was suggestive of a lesion localized to the L4-S3 spinal cord segments. No abnormalities were seen on magnetic resonance imaging (MRI) performed in the dog in dorsal recumbency and the hips in a neutral position and the conus medullaris ended halfway the vertebral body of L7. An MRI of the hips in extended and flexed positions demonstrated minimal displacement of the conus medullaris in the cranial and caudal directions, respectively. Similar to the images in neutral position, the conus medullaris ended halfway the vertebral body of L7 in both the extended and flexed positions. In comparison, an MRI of the hips in neutral, extended, and flexed positions performed in another English Cocker Spaniel revealed obvious cranial displacement of the conus medullaris with the hips in extension and caudal displacement with hips in flexion. A standard dorsal lumbosacral laminectomy was performed. Visual inspection of the vertebral canal revealed excessive caudal traction on the conus medullaris. After sectioning the distal aspect of the filum terminale, the conus medullaris regained a more cranial position. A neurological examination 4 weeks after surgery revealed clinical improvement. Neurological examinations at 2, 4, 7, and 12 months after surgery did not reveal any abnormalities, and the dog was considered to be clinically normal. Tethered cord syndrome with a tight filum terminale is a very rare congenital anomaly and is characterized by an abnormally short and inelastic filum terminale. Therefore, this disorder is associated with abnormal caudal traction on the spinal cord and decreased physiological craniocaudal movements of the neural structures within the vertebral canal. Although further studies are necessary to evaluate and quantify physiological craniocaudal movement of the spinal cord and conus medullaris in neurologically normal dogs, the results of this report suggest further exploration of dynamic MRI to demonstrate decreased craniocaudal displacement of the conus medullaris in dogs with tethered cord syndrome with a tight filum terminale.