Syringomyelia and Arnold Chiari in scoliosis initially classified as idiopathic: Experience with 25 patients

The authors analysed the clinical and radiological findings and the surgical management of 25 patients admitted for scoliosis classified as idiopathic at first presentation, but in fact associated with spinal cord and/or brain stem anomalies. Twenty patients had syringomyelia, 19 had Chiari malformation. Scoliosis was the only presenting symptom when all these patients were referred to the orthopaedic surgeon. On examination, five patients had normal neurological findings, while the others showed very mild neurological deficits. The diagnosis of syringomyelia and Chiari malformation was established by MRI, which is the best form of neuroradiological examination for discovering spinal abnormalities. Neurosurgical treatment is strongly recommended as the first step in the management of “pseudo” idiopathic scoliosis.     

"特发性"胸椎左侧凸患者并发脊髓病变及其临床意义

目的 探讨对临床上无明显神经损害的"特发性"胸椎左侧凸患者存在的脊髓病变情况,并分析其临床意义.方法 1997年10月至2003年10月共诊治"特发性"胸椎左侧凸59例,其中男性31例,女性28例;年龄7～44岁,平均15岁;Cobb角15°～108°,平均56°.所有病例经临床及影像学检查,排除神经纤维瘤及先天性脊椎发育异常等病因.对临床诊断为"特发性"胸椎左侧凸的患者行全脊髓磁共振成像(MRI)检查,对脊髓病变的发生率进行统计.结果 59例"特发性"胸椎左侧凸患者经全脊髓MRI检查后,共有33例发现髓内病变,髓内病变发生率为56%,其中Chiari畸形合并脊髓空洞24例,脊髓空洞5例,Chiari畸形、脊髓空洞、脊髓裂1例,Chiari畸形、脊髓空洞、脊髓栓系1例,脊髓空洞合并栓系1例,Dandy-Walker畸形1例.其余26例未发现脊髓病变.分析伴有脊髓病变的胸椎左侧凸患者中男性比例及平均Cobb角均显著大于无脊髓病变的胸椎左侧凸(P＜0.05).结论 对于胸椎左侧凸,尤其是男性、Cobb角较大的患者需高度怀疑伴有脊髓病变.对于此类患者术前常规全脊髓MRI检查具有重要意义.     

Neuraxial analgesia during labor in a patient with Arnold-Chiari type I malformation and syringomyelia

Chiari type I malformation is a caudal displacement of the cerebellum with tonsillar herniation through the foramen magnum, frequently associated with syringomyelia, a syndrome characterized by cyst-like cavities in the spinal cord; each of the conditions leads to characteristic neurologic abnormalities. Pregnant patients with these types of malformation are considered to have an increased risk of brainstem compression and/or progression of the disease during labor. We present the case of a patient in labor with a diagnosis of syringomyelia associated with Chiari type I malformation and describe the anesthetic management. The patient revealed during labor that she had syringomyelia associated with Chiari type I malformation, after having made no mention of it in previous history taking. Finally, we review the pathology observed in these patients.     

Fulcrum-bending像与伴发脊髓空洞或(和)Chiari畸形脊柱侧凸的手术治疗

[目的]探讨Fulcrum-bending(支点弯曲位)像对伴发Chiari畸形和(或)脊髓空洞的脊柱侧凸手术治疗的帮助及新思路,并分析手术疗效。[方法]18例伴发脊髓空洞和(或)Chiari畸形的脊柱侧凸患者的治疗方案分两组:(1)牵引后前后路联合脊柱侧凸矫形手术(6例):对脊柱侧凸有手术矫形指征、伴发无明显神经损害的Chiari畸形和(或)脊髓空洞者,先行Halo颅骨牵引,1周后行脊柱侧凸矫形手术;(2)直接行后路脊柱侧凸矫形手术(12例):术前拍Fulcrum-bending像,并根据其结果对脊柱侧凸进行矫形。[结果]6例牵引后手术患者Cobb’s角平均矫正率为61%;6例柔软型侧凸患者直接后路手术患者均未出现神经并发症,Cobb’s角平均矫正率为60%,且术前Fulcrum-bending像与术后Cobb’s角相接近;6例僵硬型侧凸患者中1例出现轻微神经损害情况,后逐渐恢复,Cobb’s角平均矫正率为52%,手术存在过度矫正。[结论]对无明显神经损害的伴发脊髓空洞或ChiariI型畸形的脊柱侧凸柔软患者,不必行术前牵引而直接行后路手术,且可以获得与牵引后前后路联合手术类似的矫形效果。     

特发性左侧胸椎侧凸

目的：探讨特发性左侧胸椎侧凸的临床特点及其可能病因。方法：对77例特发性左侧胸椎侧凸作回顾性分析,其中23例行肌电图检查。47例行全脊柱MRI检查。结果：物理检查12例有异常神经学发现,肌电图检查23例均提示神经原性损害,MRI检查有9例证实神经异常。结论：特发性左侧腰椎侧凸与脊髓异常有关,对于此类畸形应常规行MRI检查,以免遗漏脊髓异常。     

Surgical treatment of late neurological deterioration in children with myelodysplasia

Summary Late deterioration of the neurological condition in patients operated on for myelomeningocele repair has been repeatedly reported in the literature. At the present time magnetic resonance imaging (MRI) allows one to recognize various pathological conditions which can be amenable to surgical correction in these patients, such as Chiari type II malformation, hydro/syringomyelia, decompensated hydrocephalus, and tethered spinal cord.The authors report their experience with 26 myelodysplastic children operated on for myelomeningocele repair in the early neonatal period, who exhibited late deterioration at variable time intervals from the first operation. The children were examined pre-operatively by means of MRI; the results were compared with those provided by MRI in 46 myelodysplastic children who underwent the investigation as a routine follow-up control. The MRI findings were subdivided into 4 main groups of increasing severity from 1 to 4; in some subjects, associated pathological conditions (Chiari II malformation, hydromyelia, etc.) were detected as well.Twenty-two out of the 26 patients with late neurological deterioration were operated on. Eleven of them (grades 2 to 4) underwent detethering of the fixed conus, with an improvement of their clinical picture from mild to good. On the other hand the remaining 11 subjects (grades 1 to 2) improved their condition following the correction of the associated abnormalities (malfunctioning CSF shunt: 5 cases; hydromyelia: 4 cases; symptomatic Chiari II malformation: 2 cases).     

Incidentally identified syringomyelia associated with Chiari I malformations: is early interventional surgery necessary?

OBJECTIVE: The purpose of this study was to analyze clinical data and magnetic resonance imaging (MRI) findings for patients with asymptomatic, incidentally identified syringomyelia associated with Chiari I malformations who were monitored for more than 10 years, and to clarify the natural history of these lesions. METHODS: The clinical records of nine patients who had not been surgically treated and were regularly subjected to neurological and MRI examinations were analyzed. In MRI studies, the axial diameter of the syrinx at the widest level, the longitudinal extent of the syrinx, and the extent of tonsillar herniation into the spinal canal were analyzed. As a control, MRI findings for 11 patients with symptomatic syringomyelia associated with Chiari I malformations who had been surgically treated were also analyzed, and these MRI parameters were statistically compared between the asymptomatic and symptomatic groups. RESULTS: One patient underwent surgery, because of neurological changes, 7 years after the first visit. None of the remaining patients demonstrated any neurological change during the follow-up period (11.2+/-0.7 yr), and all of them have been faring well without surgery. No statistically significant differences in MRI findings between the asymptomatic and symptomatic groups were observed. CONCLUSION: The long-term clinical courses of patients with asymptomatic, incidentally identified syringomyelia associated with Chiari I malformations were observed to be benign. MRI parameters did not provide predictable values to recommend interventional surgery. Unless changes in neurological or MRI findings are detected, early interventional surgery is not necessary.     

The correlation between coronal balance and neuroaxial abnormalities detected on MRI in adolescent idiopathic scoliosis

Introduction

The indications for magnetic resonance imaging in presumed adolescent idiopathic scoliosis (AIS) have not been established, with some studies suggesting that rates of spinal cord abnormalities are low and question the use of the routine MRI in AIS.

Objective

Given the restraints on MRI resources the authors performed a retrospective audit to see if the presence of coronal or sagittal misbalance–balance could be used as a surrogate marker for the presence of spinal cord abnormalities in this patient group and hence reduce the need for unnecessary MRI scans.

Methods

We performed a retrospective review of imaging of patients with AIS at our centre over a 2-year-period. All MRI scans were reported by the senior author and the presence of spinal cord abnormalities noted. All plain films were assessed by a senior SpR and ST2 orthopaedic surgeons for Cobb angle, coronal balance, sagittal balance and Lenke classification.

Results

A total of 171 patients were identified with AIS. Of these, a total of 15 patients (9%) were found to have neural axis anomalies on MRI including syringomyelia, Chiari malformations and dural ectasia. The average Cobb angle was 44.9° with coronal balance varying from 67.2 mm left to 40.2 mm right. Sagittal balance varied from 125 mm negative to 83 mm positive. No correlation was found between coronal/sagittal misbalance and the presence of neural axis anomalies.

Conclusions

Our audit demonstrates that neither coronal nor sagittal misbalance should be used as an indicator of neural axis abnormalities.     

Surgical treatment of syringomyelia. Selection of surgical procedures

The surgical approach to syringomyelia is controversial. In this study, the authors evaluated the results of various operative procedures applied in 31 patients with syringomyelia. Syringomyelia was associated with Chiari malformation in 17 cases, with spinal adhesive arachnoiditis in nine, with trauma in three, and with epidural arachnoid cyst in one. One case was idiopathic. A total of 38 operations were performed. Syringosubarachnoid shunting was applied in 17 patients, syringoperitoneal shunting in 11, terminal syringostomy in three, ventriculoperitoneal shunting in three, lumboperitoneal shunting in two, foramen magnum decompression (suboccipital craniectomy plus upper cervical laminectomy) and terminal syringostomy in one, and foramen magnum decompression with syringosubarachnoid shunting in one. The postoperative follow-up period ranged from 2 to 55 months (average, 26 months). Of the 31 patients, 23 showed neurological improvement, five were unchanged, and three deteriorated. Among the last three, one patient with Chiari malformation developed shunt malfunction due to arachnoiditis after syringosubarachnoid shunting. In two patients with syringomyelia secondary to adhesive arachnoiditis, the spinal cord was damaged by extensive separation of the arachnoid membrane at surgery. On the basis of the results in these 31 cases, the authors conclude that syringosubarachnoid shunting is effective for syringomyelia associated with Chiari malformation if syringomyelia is responsible for the clinical symptoms. Post-traumatic syringomyelia and syringomyelia secondary to adhesive arachnoiditis should be treated by syringoperitoneal shunting. If hydrocephalus is present, ventriculoperitoneal shunting is indicated. Finally, terminal syringostomy is no more effective than syringosubarachnoid or syringoperitoneal shunting.     

14 cases of communicating syringomyelia associated with Chiari I malformation in children]

The authors review their experience of 14 children with syringomyelia and associated Chiari I malformation observed during the last 21 years. Initial symptoms were motor weakness (57%), sensory signs (50%), scoliosis (50%) and bladder dysfunction (21.5%), while signs of admission were pyramidal signs (78.5%) with motor deficit (43%), spinal deformities (64.2%), syringomyelic syndrome (36%) and sensory deficit (21.5%). Four children were investigated with myelography, three with myelography and spinal CT Scan and the last seven cases with MRI. Ten children (71.4%) underwent a decompression of the Chiari malformation with or without drainage of the cyst and shunting of an associated hydrocephalus. Syringo-peritoneal shunts were used in 3 children and laminectomy with syringo-subarachnoid shunt in 1 case. The neurological symptoms improved in 57% of the cases, 2 patients deteriorated and 4 patients were lost to follow-up. The authors discuss the clinical symptomatology, the MRI study, the controversies concerning the treatment and concluded with their attitude concerning this pathology in children.     

One-stage and posterior approach for correction of moderate to severe scoliosis in adolescents associated with Chiari I malformation: is a prior suboccipital decompression always necessary?

Priority of neurological decompression was regarded as necessary for scoliosis patients associated with Chiari I malformation in order to decrease the risk of spinal cord injury from scoliosis surgery. We report a retrospective series of scoliosis associated with Chiari I malformation in 13 adolescent patients and explore the effectiveness and safety of posterior scoliosis correction without suboccipital decompression. One-stage posterior approach total vertebral column resection was performed in seven patients with scoliosis or kyphosis curve >90° (average 100.1° scoliotic and 97.1° kyphotic curves) or presented with apparent neurological deficits, whereas the other six patients underwent posterior pedicle screw instrumentation for correction of spinal deformity alone (average 77.3° scoliotic and 44.0° kyphotic curves). The apex of the scoliosis curve was located at T7–T12. Mean operating time and intraoperative hemorrhage was 463 min and 5,190 ml in patients undergoing total vertebral column resection, with average correction rate of scoliosis and kyphosis being 63.3 and 71.1%, respectively. Mean operating time and intraoperative hemorrhage in patients undergoing instrumentation alone was 246 min and 1,450 ml, with the average correction rate of scoliosis and kyphosis being 60.8 and 53.4%, respectively. The mean follow-up duration was 32.2 months. No iatrogenic neurological deterioration had been encountered during the operation procedure and follow-up. After vertebral column resection, neurological dysfunctions such as relaxation of anal sphincter or hypermyotonia that occurred in three patients preoperatively improved gradually. In summary, suboccipital decompression prior to correction of spine deformity may not always be necessary for adolescent patients with scoliosis associated with Chiari I malformation. Particularly in patients with a severe and rigid curve or with significant neurological deficits, posterior approach total vertebral column resection is likely a good option, which could not only result in satisfactory correction of deformity, but also decrease the risk of neurological injury secondary to surgical intervention by shortening spine and reducing the tension of spinal cord.     

Wirbelsäulenerkrankungen und assoziierte ZNS-Fehlbildungen – Tethered-Cord und Arnold-Chiari-Fehlbildung

Tethered cord syndrome (TCS) and the Chiari malformation (CM) are generally related to congenital malformations, but both entities can be acquired.TCS often presents with progressing sensory and motor symptoms that can be attributed to increased tension of the spinal cord. Fixation of the spinal cord can occur congenitally (primary TCS) or in association with other intraspinal pathologies or postoperative scarring (secondary TCS). Exact diagnosis in the adult can be difficult if symptoms are interpreted as being related to degenerative disorders of the spine. In the presence of neurological symptoms, surgery is indicated. A preventive surgical procedure in asymptomatic patients is discussed controversially in the literature and is established in TCS patients only with correction of a scoliosis. However, most patients suffering from TCS benefit from surgical treatment.CM can be divided into four abnormal alterations of the posterior fossa, with most cases being of types I and II. In adults, Chiari type I is most common. Chiari I may present congenitally; however, it is also secondarily observed following lumboperitoneal shunting or in association with hydrocephalus. Surgical intervention is recommended depending on the extent of herniated tissue and the neurological symptoms. The optimal surgical procedure is still controversial. Most centers recommend bony decompression with dural graft extension for Chiari I.The appropriate treatment of both complex disorders requires a close and critical interdisciplinary approach in order to offer patients an individually adapted therapy.     

Spinal cord edema preceding syringomyelia associated with Chiari I malformation--case report

A 38-year-old woman with Chiari I malformation presented with spinal cord edema preceding syringomyelia manifesting as a 5-month history of nuchal pain and numbness of the upper extremities. Magnetic resonance imaging showed spinal cord edema, a poorly defined syrinx at the C-2 to T-2 levels, and distorted cerebellar tonsils. Computed tomography revealed cerebrospinal fluid (CSF) density in the center of spinal cord edema, and positron emission tomography revealed no uptake of L-[methyl-11C]methionine, indicating a non-neoplastic lesion. Craniocervical decompression achieved excellent clinical and neuroradiological outcomes. The success of surgical treatment supports the theory that patients with Chiari I malformation have increased transmural flow of CSF, causing spinal cord edema that progresses to syringomyelia. Early treatment of patients with spinal cord edema is indicated to prevent permanent spinal cord injury due to progressive syringomyelia.     

Results of the section of the filum terminale in 20 patients with syringomyelia,scoliosis and Chiari malformation

Summary Background. Spinal cord traction caused by a tight filum terminale may be considered a pathogenic mechanism involved in the development of syringomyelia, the Chiari malformation (type I) and scoliosis. Section of the filum terminale is proposed as a useful surgical approach in these conditions.Methods. Between April 1993 and July 2003, a total of 20 patients (8 men and 12 women) with a mean age of 33.5 years underwent section of the filum terminale with or without opening of the dural sac through a standard sacrectomy. Eight patients suffered from scoliosis, 5 from syringomyelia, 2 from Chiari malformation and 5 with a combination of these conditions.Finding. After section of the filum terminale, patients with syringomyelia showed an early clinical improvement of dysaesthesia, thermo-anaesthesia, hypo-aesthesia and walking difficulties. Rising of the medullary conus was also observed. In patients with scoliosis, back pain improved dramatically and a curve reduction was noticed, although progression of the curve was observed in one case. In patients with Chiari malformation, headache, dysaesthesia and paraparesis disappeared.Conclusions. Section of the filum terminale is a useful strategy in the treatment of scoliosis, syringomyelia and the Chiari malformation, and offers a new aetiological basis for the understanding of these three disorders.     

Spontaneous resolution of a Chiari I malformation associated syringomyelia in one child

Summary A child with complete spontaneous resolution of a Chiari I malformation associated Syringomyelia without surgical intervention is presented. The child was followed clinically by serial magnetic resonance imaging (MRI) and remains neurologically stable after 8-years of follow-up. To our knowledge, only 6 pediatric cases with spontaneous resolution of a spinal cord syrinx documented by MRI without surgical intervention have been reported. This case is of interest in the light of the postulated theories to explain spontaneous resolution of syringomyelia.     

Factors associated with early onset post-traumatic syringomyelia

Study design:Retrospective study.Objectives:To identify factors associated with the development of early onset post-traumatic syringomyelia within 5 years of spinal cord injury.Setting:Department of Rehabilitation Medicine, Pusan National University School of Medicine, Korea.Methods:We retrospectively examined the records of 502 patients with traumatic cervical or thoracic spinal cord injury who underwent follow-up magnetic resonance imaging (MRI) examinations more than once a year for at least 5 years. Patients were assessed in terms of the neurological level of injury, the severity of initial spinal cord injury, the use of surgery and the extent of spinal canal involvement. The latter was evaluated by calculating the shortest antero-posterior diameter of the injured vertebral canal and the spinal reserve capacity as shown on MRI at the time of trauma onset and at the time of diagnosis of syringomyelia.Results:Syringomyelia developed within 5 years in 37 (7.3%) of the 502 patients. The mean age of these 37 patients was 44.6 years (range, 17-67 years) and the mean interval from spinal cord injury to onset of syringomyelia was 38.8 months (range, 2-54 months). The development of post-traumatic syringomyelia within 5 years was not significantly related to the severity or level of injury, the use of spinal surgery or the extent of spinal canal encroachment (P≥0.05 for each comparison).Conclusion:Early onset syringomyelia occurring within 5 years after spinal cord injury was not associated with neurological injury level, severity of injury, the use of spinal surgery or canal encroachment.     

Evaluating congenital spine deformities for intraspinal anomalies with magnetic resonance imaging.

SUMMARY: The incidence of intraspinal abnormalities associated with congenital spinal anomalies as detected by magnetic resonance imaging (MRI) is becoming better defined. In this study, 41 nonrandomized children with congenital spinal deformities (excluding myelomeningocele) who underwent complete MR evaluation were reviewed. Of the 41 congenital spinal deformities, 37 demonstrated congenital scoliosis, with failure of formation in 19, failure of segmentation in 4, and mixed defects in 14. The remaining four deformities were cases of congenital kyphosis. Thirteen patients with congenital spine anomalies were noted to have intraspinal abnormalities identified by MRI: tethered cord in 12 patients, syringomyelia in 3 patients, and diastematomyelia in 5 patients. Of the 12 patients with tethered cord, 2 patients had neurologic deficits. Urorectal anomaly was one of the most common associated findings (15%). Considering an incidence of intraspinal anomalies of 31% and as clinical manifestations may not be initially detectable, MRI is recommended in patients with congenital spinal deformity as part of the initial evaluation even in the absence of clinical findings.     

Generalised spinal cord atrophy, Chiari-I malformation, and syringomyelia

OBJECTIVES: To report the simultaneous occurrence of generalised spinal cord atrophy, Chiari-I malformation, and syringomyelia. SETTING: Vienna, Austria. CASE DESCRIPTION: An 83-year old woman presented with predominantly lower limb and distal tetraparesis, diffuse wasting, spasticity of both lower limbs, contractures, and severe kyphoscoliosis. Radiographic examinations revealed generalised spinal cord atrophy, Chiari-I malformation, and syringomyelia between C5 and C7. The generalised spinal cord atrophy was assumed to be due to either secondary atrophy or spontaneous collapse of a formerly more extensive syringomyelia. All other causes for generalised spinal cord atrophy were excluded. CONCLUSIONS: Generalised spinal cord atrophy in a patient with Chiari-I malformation and syringomyelia may be due to either secondary atrophy or spontaneous collapse of a formerly holocord syringomyelia. Myelography and MRI imaging of the spine are helpful in diagnosing this condition.     

Surgical management of syringomyelia–Chiari complex

Great variety exists in the indications and techniques recommended for the surgical treatment of syringomyelia–Chiari complex. More recently, magnetic resonance (MR) imaging has increased the frequency of diagnosis of this pathology and offered a unique opportunity to visualize cavities inside the spinal cord as well as their relationship to the cranio-cervical junction. This report presents 18 consecutive adult symptomatic syringomyelia patients with Chiari malformation who underwent foramen magnum decompression and syringosubarachnoid shunting. The principal indication for the surgery was significant progressive neurological deterioration. All patients underwent preoperative and postoperative MRI scans and were studied clinically and radiologically to assess the changes in the syrinx and their neurological picture after surgical intervention. All patients have been followed up for at least 36 months. No operative mortality was encountered; 88.9% of the patients showed improvement of neurological deficits together with radiological improvement and 11.1% of them revealed collapse of the syrinx cavity but no change in neurological status. None of the patients showed further deterioration of neurological function. The experience obtained from this study demonstrates that foramen magnum decompression to free the cerebro-spinal fluid (CSF) pathways combined with a syringosubarachnoid shunt performed at the same operation succeeds in effectively decompressing the syrinx cavity, and follow-up MR images reveal that this collapse is maintained. In view of these facts, we strongly recommend this technique, which seems to be the most rational surgical procedure in the treatment of syringomyelia– Chiari complex. Received: 11 October 1999 Revised: 29 February 2000 Accepted: 20 March 2000     

Syringomyelia associated with arachnoid septum at the craniovertebral junction, contradicting the currently prevailing theory of syringomyelia formation

Despite a number of various hypotheses in the literature, the pathophysiology of syringomyelia is still not well understood. In this article, we report two cases of cervical syringomyelia not associated with Chiari I malformation. Both cases had a septum-like structure in the subarachnoid space on the dorsal side of the cord at the craniovertebral junction. Cardiac-gated phase-contrast cine-mode magnetic resonance imaging (MRI) demonstrated decreased cerebrospinal fluid (CSF) flow on the dorsal side of the spinal cord. Surgical excision of this septum, restoring the CSF flow, resulted in a prompt reduction of the syrinx size in both cases. Findings in these cases contradict the currently prevailing hypothesis of syrinx formation that postulate that the piston-like movement of the cerebellar tonsils enhance the pulsatile CSF flow in the spinal subarachnoid space, driving the CSF into the syrinx through the perivascular space of Virchow and Robin. The authors propose that a mechanism based on the decreased pulsatile CSF flow in the spinal subarachnoid space will be more suitable as a hypothesis in studying the pathophyisiology of syringomyelia. These cases also provide an important lesson in managing the patients with syringomyelia not associated with Chiari I malformation.