点击显示 收起
【摘要】 目的 调查先天性脊柱侧凸患儿脊髓异常的发生率并探讨影像学诊断的地位。方法 107例先天性脊柱侧凸病例中合并脊髓异常者36例，占33.6%。所有病例均摄X线平片，脊髓造影或CT脊髓造影25例，MRI检查27例。结果 36例脊髓异常中脊髓栓系26例，二分脊髓8例，脊髓纵裂9例，脊髓空洞7例，低位圆锥8例。其中MRI检查27例均提示脊髓异常。结论 先天性脊柱侧凸患儿常合并脊髓异常，对有症状者及拟手术治疗病例应常规行MRI检查。
Spinal Cord Abnormalities in Congenital Scoliosis
DAI Liyang.
Depatrment of Orthopaedics Surgery. Changzheng Hospital, Shanghai 200003
【Abstract】 Objective To determine the incidence of spinal cord abnormality in patients with congenital scoliosis and evaluate the role of imaging studies in the diagnosis.Methods Radiological imaging studies on patients with congenital scoliosis were reviewed.Results Of 107 patients with congenital scoliosis, 36 patients (33.6%) were found to have abnormalities of spinal cord. All of the 36 patients had spinal X-ray film, 25 had myelogram or CT myelogram and 27 had MRI examination. The abnormalities included 26 tethered cords, 8 diastematomyelia, 9 diplomyelia, 7 syringomyelia, and 8 low lying conus. MRI examinations were all positive.Conclusions Spinal cord abnormalities are common in patients with congenital scoliosis. MRI examination is indicated in symptomatic patients before operation.
【Key words】 Scoliosis，congenital Spinal cord abnormalities MRI Myelography
虽然先天性脊柱侧凸患儿椎体发育异常在出生时即已存在，但其脊柱侧凸以及临床症状的出现时间却存在相当大的差异，其中主要影响因素之一就是是否同时合并有脊髓异常。目前对于这一问题尚缺乏系统研究，本文报道对一组107例先天性脊柱侧凸患儿的回顾性分析结果，并结合有关文献对这一问题进行讨论。
临 床 资 料
一、研究对象
我院1975～1997年诊治的小儿先天性脊柱侧凸患儿107例，男性38例，女性69例，年龄1～14岁。其中合并脊髓异常者36例，占33.6%。
二、诊断及分类
1. 先天性脊柱侧凸：形成缺陷21例(其中半椎体畸形19例，楔形椎2例)，分节缺陷4例，混合型11例。
2. 脊髓异常：脊髓栓系26例，二分脊髓8例，脊髓纵裂9例，脊髓空洞7例，低位圆锥8例。
三、临床症状
有31名患儿存在不同程度的临床症状。腰背疼痛15例；下肢软弱无力9例；下肢疼痛和/或感觉异常12例；尿频、尿流不连续8例。
四、体检发现
11名患儿体检有异常发现。下肢肌肉萎缩和/或肌力减退4例；下肢感觉异常5例；下肢不等长2例；下肢反射异常3例；腰骶部皮肤外观异常3例。
五、影像学检查
1. X线平片：所有病例均摄全脊柱X线平片，其中19例检查结果提示脊髓异常，椎弓根间距增宽15例，骨嵴7例。
2. 脊髓造影：检查25例(含CTM 16例)，其中17例提示脊髓异常，造影剂充盈缺损14例，二分脊髓或脊髓纵裂9例。
3. MRI：检查27例，均提示脊髓异常，脊髓栓系18例，二分脊髓4例，脊髓纵裂2例，脊髓空洞7例，低位圆锥3例。
讨 论
关于脊髓异常在先天性脊柱侧凸患儿中的发生率目前报道较少，其结果也并不一致。Wynne-Davies［1］对337名先天性脊柱畸形患儿进行调查，发现先天性脊柱畸形与神经管缺陷有密切关系。Winter等［2］回顾一组392例先天性脊柱侧凸，证实仅4.9%合并脊髓纵裂，但他们并未提及是否同时合并其他脊髓异常，且诊断过程中仅有一部分病例行脊髓造影检查。McMaster［3］统计251例先天性脊柱侧凸46例合并有脊髓异常，占18.3%。其中脊髓纵裂最常见(41例)。然而，在这一组资料中行脊髓造影者也不到半数(106例)。而Blake等［4］对108例脊柱侧凸行CT脊髓造影检查，结果脊髓异常发生率竟高达58%，其中脊髓纵裂占21%。由此可见X线平片虽可准确显示先天性脊柱侧凸的畸形类型及程度，但却无法直接反映脊髓的异常改变。
长期以来，脊髓造影一直被用作诊断椎管内异常的重要手段。其可反映椎管内梗阻程度，并能较为清晰地显示某些类型脊髓畸形，如同时行CT扫描(CT脊髓造影)则效果更为理想。Pang［5］对一组脊髓畸形患儿的影像学资料分析表明，CT脊髓造影的诊断准确率要高于MRI，这主要体现在其显示脊髓分裂的骨和/或纤维性中隔时更具优越性。但脊髓造影属有创性检查，故该作者主张先用MRI行筛选检查，然后再对可疑者作CT脊髓造影，而Davis等［6］对81例脊柱脊髓异常的CT脊髓造影与MRI检查结果进行比较，并与手术结果对照，证实对于神经管闭合不全病例，MRI可显示多数异常改变如脊髓空洞、肿瘤及脊髓栓系部位等，T2加权像尚有助于空洞与脊髓纵裂的鉴别，但对于终丝增厚或评价背侧神经板引起的栓系较为困难。从本组资料来看，MRI对于脊髓空洞的诊断尤为敏感和准确，7例中仅有1例临床症状和体征提示脊髓空洞，经MRI检查后方作出诊断。脊柱侧凸常为脊髓空洞症的首发临床表现［7，8］，MRI检查有助于早期发现脊柱侧凸患儿的并存脊髓异常。目前对于特发性脊柱侧凸患儿是否应行脊柱MRI检查尚有争论［9，10］，鉴于先天性脊柱侧凸合并脊髓异常比例更高，预后亦更难预测，因此对有症状患儿尤其是对拟行手术治疗的患儿应常规行MRI检查。
以往曾有作者［11］报道，当一侧脊柱分节缺陷合并另一侧半椎体畸形时，发生脊髓异常的危险性较大。本组中共有9例。因此对于此类畸形亦应常规行MRI检查，以免遗漏脊髓异常。
参考文献
1 Wynne-Davies R. Congenital vertebral anomalies: aetiology and relationship to spina bifida cystica. J Med Genet, 1975, 12:280-288.
2 Winter RB, Haven JJ, Moe JH, et al. Diastematomyelia and congenital spine deformities. J Bone Joint Surg(Am), 1974, 56:27-39.
3 McMaster MJ. Occult intraspinal anomalies and congenital scoliosis. J Bone Joint Surg(Am), 1984, 66:588-601.
4 Blake NS, Lynch AS, Dowling FE. Spinal cord abnormalities in congenital scoliosis. Ann Radiol, 1986, 29:377-379.
5 Pang D. Split cord maiformation. part Ⅱ: clinical syndrome. Neurosurgery, 1992, 31:481-500.
6 Davis PC, Hoffman JC Jr, Ball TI, et al. Spinal abnormalities in pediatric patients: MR imaging findings compared with clinical, myelographic, and surgical findings. Radiology, 1988, 166:679-685.
7 Samuelsson L, Lindell D, Kogler H. Spinal cord and brain stem anomalies in scoliosis: MR screening of 26 cases. Acta Orthop Scand, 1991, 62:403-406.
8 Pravda J, Ghelman B, Levine DB. Syringomyelia associated with congenital scoliosis: a case report. Spine, 1992, 17:372-374.
9 Winter RB, Lonstein JE, Heithoff KB, et al. Magnetic resonance imaging evaluation of the adolescent patient with idiopathic scoliosis before spinal instrumentation and fusion: a prospective, doubleblinded study of 140 patients. Spine, 1997, 22:855-858.
10 Gupta P, Lenke LG, Bridwell KH. Incidence of neural axis abnormalities in infantile and juvenile patients with spinal deformity: is a magnetic resonance image screening necessary Spine, 1998, 23:206-210.
11 Bradford DS, Heithoff KB, Cohen M. Intraspinal abnormalities and congenital spine deformities: a radiographic and MRI study. J Pediatr Orthop, 1991, 11:36-41.