Cause Of Syringomyelia Research Articles

Optimizing Therapeutic Strategies for Syringomyelia Associated with Tethered Cord Syndrome: A Comprehensive Review.

This review highlights the need for therapeutic guidelines for syringomyelia associated with tethered cord syndrome (TCS) caused by spinal dysraphism (SD). A comprehensive literature review was conducted, selecting twelve articles to analyze common therapeutic strategies. Surgical cord untethering alone has recently become a preferred treatment, with 45 ± 21.1% of patients experiencing remission or improvement, 47 ± 20.4% unchanged and asymptomatic, and 4 ± 8% worsened. Untethering with direct surgical drainage for the syrinx had better outcomes than untethering alone (78% vs. 45%, p = 0.05). Terminal syringostomy was beneficial for syrinxes extending to the filum terminale but not for asymptomatic small syrinxes with a syrinx index < 0.4. Syrinx shunting was recommended for symptomatic large syrinxes (>2 cm in length and syrinx index > 0.5). Various shunt procedures for syrinxes are still advocated, mainly for refractory syringomyelia in Chiari malformation, posttraumatic cases, SD, or other causes. Personalized surgical methods that address the root cause of syringomyelia, particularly those improving cerebrospinal fluid flow, offer promising results with minimized complications. Ongoing studies are required to enhance management strategies for syringomyelia associated with TCS, optimize patient outcomes, and reduce the risk of recurrent symptoms.

Syringomyelia secondary to Thoracic Intervertebral Disc Protrusion: A rare condition

Spinal spondylosis is an extremely common problem among the middle-aged and elderly population. However, it is an extremely rare cause of syringomyelia in clinical practice. The differentiation between syringomyelia and hydromyelia is not always straightforward and rather exhaustive. Spinal cord compression and instability are the proposed mechanisms of injury-causing syringomyelia. Symptomatic presentation depends primarily on the location of the syrinx within the neuraxis, be it motor, sensory or autonomic disturbance. There were abundant of successful cases in the past, whereby surgical interventions can regress the appearance of syringomyelia in magnetic resonance imaging. However, there was a mixed result in terms of patients' symptom. There were only 6 reported articles of syringomyelia secondary to cervical spondylosis found worldwide. We describe a case of T11/T12 thoracic intervertebral disc protrusion causing long segment syringomyelia till conus medullaris.

Dorsal hemangioblastoma with holocord syringomyelia: case report

Introduction: Intramedullary hemangioblastomas are usually accompanied by syringomyelia. However, a holocord syringomyelia is rare. The most common cause of syringomyelia continues to be Chiari disease, and only 10 cases of hemangioblastomas with holocord syringomyelia reported so far. Case report: We present a case of a 35-year-old patient with a two-month history of cervicobrachialgia at the C7-C8 root level, previously preceded by pain at the D1-D2 level. Cervico-dorso-lumbar MRI revealed a medullar tumor with hyper-uptake mural nodule at the conus medullaris level accompanied by an extensive syringomyelic cavity from C5 to L1 compatible with medullary hemangioblastoma. The patient underwent surgery for tumor resection with subsequent resolution of her painful symptoms. Conclusion: It is important to note that the surgery is aimed at treating the origin of this syringomyelia and not the syringomyelia itself. Although the majority of patients with holocord syringomyelia have Chiari as its cause, the possibility of focal spinal intramedullary tumors as being responsible for syringomyelia should not be forgotten.

Dorsal arachnoid web: A rare cause of syringomyelia and myelopathy

Dorsal arachnoidal webs are condensations of arachnoidal tissue densely adherent to the pial surface of the posterior aspect of the dorsal spinal cord. Infrequently described in literature they disrupt the flow of CSF in the spinal subarachnoid space leading to syringomyelia and myelopathy. While there are several theories on their origin, the “scalpel sign” on magnetic resonance imaging is considered to be pathognomonic of this condition. An illustrative case of a 58 year old man with syringomyelia and dorsal cord indentation who presented with spastic paraparesis, gait instability, parasthesias and bilateral non radicular upper limb pain that resolved following excision of the web is described to highlight the importance of considering this diagnosis when cases of so called “idiopathic” syringomyelia are encountered. Las membranas aracnoideas dorsales son condensaciones de tejido aracnoideo densamente adherido a la superficie pial de la cara posterior de la médula espinal dorsal. Descritas con poca frecuencia en la literatura, interrumpen el flujo del líquido cefalorraquídeo (LCR) en el espacio subaracnoideo espinal y provocan siringomielia y mielopatía. Si bien existen varias teorías sobre su origen, el «signo del bisturí» en la resonancia magnética se considera patognomónico de esta afección. Se describe un caso ilustrativo de un varón de 58 años con siringomielia e indentación medular dorsal que presentó paraparesia espástica, inestabilidad de la marcha, parestesias y dolor bilateral no radicular en miembro superior que se resolvió tras la exéresis de la telaraña para resaltar la importancia de considerar este diagnóstico cuando se encuentran casos de la llamada siringomielia «idiopática».

A Shunt Method for the Treatment of Syringomyelia Secondary to Trauma and Tuberculous Meningitis

The pathogenesis and surgical treatment of syringomyelia (SM) secondary to trauma and tuberculous meningitis are not clear. We hypothesize that the main cause of SM is impaired cerebrospinal fluid circulation in the subarachnoid space due to spinal arachnoid adhesion induced by trauma or tuberculous meningitis. Using trans-segmental subarachnoid shuntsurgery, we re-established normal cerebrospinal fluid circulation in the subarachnoid space, which resolved the potential cause of SM formation. This study aimed to evaluate the efficacy of trans-segmental subarachnoid shunt surgery in the treatment of SM secondary to trauma or tuberculous meningitis. A total of 143 patients with SM after trauma and tuberculous meningitis were recruited between September 2014 and February 2017. Among these patients, 64 had posttraumatic SM, including 39 males and 25 females with an age range of 21–65 years and an average age of 40.02 years, and 79 patients had SM secondary to tuberculous meningitis, including 49 males and 30 females with an age range of 23–62 years and an average age of 44.95 years. All patients underwent trans-segmental subarachnoid shunt surgery and were subjected to magnetic resonance imaging (MRI) examination between 6 months and 1 year and between 2 and 2.5 years after surgery. Clinical efficacy was assessed by the Tator method. The main symptoms or signs were evaluated by improvement, stabilizationor aggravation of symptoms. Patients were followed-up twice, once at 6 months to 1 year after surgery and once at 2 to 2.5 years after surgery. A total of 143 patients were followed-up for the first time, among whom, the clinical symptoms were improved in 59 patients(41.26%), stable in 51 patients (35.66%) and aggravated in 36 patients (23.08%). MRI exaination showed that the spinal cord cavities completely disappeared in 27 patients (18.88%), shrank significantly in 71 patients (49.65%), did not change or shrink significantly in 32 patients (22.38%) and expanded in 13 patients (9.09%). A total of 122 patients were followed-up for the second time, and the clinical symptoms were improved in 69 patients (56.56%), stable in 25 patients (20.49%) and aggravated in 28 patients (22.95%). Compared to the condition in the first follow-up, 14 patients who were stable were improved, 5 patients who were aggravated were improved, and the symptoms did not change significantly among other patients. The imaging examination did not show any significant change compared to that of the first follow-up. We suggest that trauma or tuberculous meningitis can induce spinal arachnoid adhesion, leading to impaired cerebrospinal fluid circulation in the subarachnoid space, which then causes SM. Trans-segmental subarachnoid shunt surgery is a noninvasive, safe and effective treatment for SM secondary to trauma and tuberculous meningitis.

DYNAMICS OF MYELOPATHIC SYMPTOMS OF SYRINGOMYELIA ASSOCIATED WITH CHIARI MALFORMATION 1 IN PATIENTS WITH POSTOPERATIVE COLLAPSE OF THE CAVITY

Syringomyelia is a chronic myelopathy with the formation of cavities in the spinal cord. The most common cause of syringomyelia is the obstruction of the cerebrospinal fl uid tract at the craniovertebral junction level in patients with Chiari malformation. The main method of treatment of syringomyelia is surgical, aimed at stopping the progression of the disease. To date, controversial data on the postoperative regression of myelopathic symptoms and factors contributing to a positive clinical outcome are presented in the world literature Goal of the study: to assess the dynamics of myelopathic symptoms of syringomyelia at the postoperative stage.Material and methods.44 patients with syringomyelia associated with Chiari 1 malformation, who underwent decompression of the posterior cranial fossa and had positive postoperative radiological dynamics of the syringomyelitis cavity were included to our retrospective study. Patients were evaluated by clinical and MRI parameters at the preoperative and distant postoperative stages.Results. Analysis of clinical and MRI indicators at the preoperative and remote postoperative stages allowed us to determine the frequency of regression of myelopathic symptoms and to identify it’s main dynamics predictors.

Treatment of Syringomyelia in Patients with Arachnoiditis at the Craniocervical Junction.

Craniocervical junction arachnoiditis (CCJA) is an uncommon cause of syringomyelia. The pathophysiology of syrinx formation is uncertain, and the appropriate management unclear. A series of cases is reported to demonstrate variations in etiology, uniformity of functional cerebrospinal fluid obstruction at the foramen magnum, and results of surgical intervention. We retrospectively analyzed the clinical and radiologic features of a consecutive series of patients treated for syringomyelia related to CCJA. Eight patients (5 male, 28-66 years old) were treated from 2000 to 2016. Magnetic resonance imaging demonstrated cervicothoracic syringomyelia in all cases, with the rostral extension of the syrinx suggesting communication with the fourth ventricle in all but one case. There was reduction of foramen magnum cerebrospinal fluid space in all cases, cerebellar ectopia in 5 cases, and fourth ventricular entrapment in 3 cases. Treatment consisted of posterior fossa decompression with either a GoreTex or pericranial patch graft. Six patients had a fourth-ventricle spinal subarachnoid shunt. Two patients had titanium mesh cranioplasty. The immediate postoperative period was associated with reduction in syrinx cavity size and improvement in neurologic symptoms in all cases. At follow-up 10-60 months postoperatively, 3 patients exhibited recurrence of the syrinx and underwent successful reoperation at the craniocervical junction. One patient with persistence of the inferior component of the syrinx was treated with a syrinx-spinal subarachnoid shunt. Most syrinx cavities associated with CCJA communicate with the fourth ventricle. Posterior fossa decompression and fourth ventricle to spinal subarachnoid space shunting appears a reasonable treatment for this form of syringomyelia.

Dandy–Walker malformation is a rare cause of syringomyelia in adults

Neural tube defects are the most common central nervous system malformation. Dandy–Walker malformation (DWM) is a rare abnormality of the posterior cranial fossa, which is generally diagnosed in the prenatal period or early infancy. The paper describes a case of the late clinical manifestation of DWM, which has caused syringomyelia. All variants of pathological changes within the Dandy–Walker complex very rarely become a cause of syringomyelia. Only four cases of DWM, in which syringomyelia was found in adults, are known. The authors believe that formation of syringomyelia cysts in these patients is associated with the impaired circulation of normal cerebrospinal fluid between the superior cistern and the subarachnoid spaces of the spinal cord due to the caudal dislocation of the cyst formed in the fourth ventricle. Decompression of the craniovertebral junction, by resecting the caudal portion of the cyst in the foramen magnum, and repair of the free communication between the superior cistern and the cerebrospinal fluid spaces of the spinal cord, which is complemented by duroplasty, are pointed out to be an optimal treatment in these patients.

Tratamiento de la siringomielia en pacientes con malformación de Chiari y craneosinostosis. Caso clínico y revisión de la bibliografía

Patients with multisutural or single craniosynostosis, often suffer from Chiari malformation and syringomyelia. The surgical management of syringomyelia in these patients is controversial. A 3-year-old girl was referred with complex craniosynostosis that had not been corrected surgically. She was asymptomatic despite the cranial MRI showed a Chiari malformation and one year later she developed a cervico-dorso-lumbar syringomyelia. She underwent a decompressive suboccipital craniectomy but subsequently suffered a worsening of syringomyelia. The intracranial pressure monitoring was pathological so it was decided to perform a decompressive bilateral fronto-parieto-temporal craniotomy and remodeling of the cranial vault, achieving a significant reduction of syringomyelia. After reviewing the literature, it is noted that there is currently no consensus on the treatment of syringomyelia in patients with craniosynostosis and Chiari malformation. Some authors recommend the simultaneous surgical suboccipital and cranial vault decompression, others only decompression of the cranial vault and other enlargement of the posterior fossa with distractors. In cases where the suboccipital decompression was performed first, the syringomyelia was not improved or stabilized. We conclude that the most effective treatment for patients with syringomyelia and craniosynostosis is decompressive remodeling of the cranial vault, as the main cause of syringomyelia is the raised intracranial pressure and lack of skull compliance.

The Cervical Spinal Canal Tapers Differently in Patients with Chiari I with and without Syringomyelia.

The cause of syringomyelia in patients with Chiari I remains uncertain. Cervical spine anatomy modifies CSF velocities, flow patterns, and pressure gradients, which may affect the spinal cord. We tested the hypothesis that cervical spinal anatomy differs between Chiari I patients with and without syringomyelia. We identified consecutive patients with Chiari I at 3 institutions and divided them into groups with and without syringomyelia. Five readers measured anteroposterior cervical spinal diameters, tonsillar herniation, and syrinx dimensions on cervical MR images. Taper ratios for C1-C7, C1-C4, and C4-C7 spinal segments were calculated by linear least squares fitting to the appropriate spinal canal diameters. Mean taper ratios and tonsillar herniation for groups were compared and tested for statistical significance with a Kruskal-Wallis test. Inter- and intrareader agreement and correlations in the data were measured. One hundred fifty patients were included, of which 49 had syringomyelia. C1-C7 taper ratios were smaller and C4-C7 taper ratios greater for patients with syringomyelia than for those without it. C1-C4 taper ratios did not differ significantly between groups. Patients with syringomyelia had, on average, greater tonsillar herniation than those without a syrinx. However, C4-C7 taper ratios were steeper, for all degrees of tonsil herniation, in patients with syringomyelia. Differences among readers did not exceed differences among patient groups. The tapering of the lower cervical spine may contribute to the development of syringomyelia in patients with Chiari I.

Surgical management of syringomyelia unrelated to Chiari malformation or spinal cord injury.

Syringomyelia is a misleading disease since the problem always lies elsewhere. Arachnoiditis, because it is radiographically difficult to discern, is an especially insidious cause. To better guide selection from among surgical treatment options for syringomyelia, we reviewed our case series of patients without Chiari malformation or spinal injury. Excluding syringomyelia due to Chiari malformation, spinal cord injury, and tumors, 32 patients (mean age 44years) were operated on between 1995 and 2013 and followed up for a mean of 53.8months. Presumed causes at diagnosis, clinical and radiological findings, type of operation, clinical and radiological outcome were reviewed. Duration of clinical history varied widely (range 6-164months). Clinical assessment was based on the McCormick classification (15 independent, 17 dependent). Causes included birth trauma, pyogenic meningitis, tuberculous meningitis, postoperative scarring, dysraphism, and basilar impression. Treatment was local decompression with arachnoid lysis and shunts. Hindbrain-related syringomyelia was differentiated from non hindbrain-related syringomyelia. Hindbrain arachnoiditis was significantly associated with radiological findings at the foramen magnum (p=0.01) and craniocervical decompression (p<0.03), with good clinical and radiological outcome at 6months and later follow-up controls (p=0.02), whereas uneven results were observed in cases of non-hindbrain arachnoiditis. To remove the cause of syringomyelia, surgical planning will rely on thorough clinical history and accurate imaging to determine the site of cerebrospinal fluid obstruction. Craniocervical decompression to dissect basal arachnoiditis in the posterior fossa can be recommended in hindbrain syringomyelia. Treatment of non-hindbrain arachnoiditis is more controversial, probably owing to uncertainties about the extent of adhesions.

Increased flow signal in compressed segments of the spinal cord in patients with cervical spondylotic myelopathy.

Prospective controlled trial. To describe a newly found increased flow signal in phase-contrast magnetic resonance imaging observed in compressed segments of the spinal cord in patients with cervical spondylotic myelopathy (CSM). Derangement of cerebrospinal fluid movement in the spine is a well-known cause of syringomyelia. However, its possible role in CSM has not been studied well, despite the fact that similar derangement takes place in CSM. In a consecutive series of 57 patients with CSM, cardiac-gated phase-contrast magnetic resonance imaging was analyzed. The amplitude of the flow signal obtained in the compressed segment of the spinal cord was compared with that obtained in the lesion-free C2 segment. It was also compared with controls obtained from 10 healthy volunteers. We also studied whether the amplitude was correlated with the severity of cervical canal stenosis, neurological symptoms, indication of surgery, and the presence of intramedullary high-intensity signal on T2-weighted images. In 33 patients who underwent decompression surgical procedures, we compared the amplitude of the flow signal between the preoperative and the postoperative study. Increased flow signal on phase-contrast study was seen in compressed segments of the spinal cord in 36 (63%) patients. The mean amplitude of the signal in the compressed segment was 0.64 ± 0.06 cm/s, whereas that in the C2 segment was 0.27 ± 0.01 and that in the controls was 0.28 ± 0.01. The flow signal linearly increased as the severity of canal stenosis increased. It significantly correlated with the symptom of upper-extremity dysesthesia, and the indication of surgery in these patients. The mean amplitude of the signal tended to be higher in those with intramedullary high-intensity signal than in those without. After decompression surgery, the increased flow signal was markedly diminished, and returned to a level comparable with the controls. Phase-contrast imaging demonstrated increased flow signal in compressed segments of the spinal cord in a majority of patients with CSM. This suggests a possible role played by derangement of cerebrospinal fluid movement in CSM. It also suggests potential usefulness of phase-contrast study in the management of patients with CSM. 2.

Syringomyelia associated with cervical spondylosis: A rare condition

Spinal spondylosis is an extremely common condition that has only rarely been described as a cause of syringomyelia. We describe a case of syringomyelia associated with cervical spondylosis admitted at our division and treated by our institute. It is the case of a 66-year-old woman. At our observation she was affected by moderate-severe spastic tetraparesis. T2-weighted magnetic resonance imaging (MRI) showed an hyperintense signal within spinal cord from C3 to T1 with a more sharply defined process in the inferior cervical spinal cord. At the same level bulging discs, facets and ligamenta flava hypertrophy determined a compression towards subarachnoid space and spinal cord. Spinal cord compression was more evident in hyperextension rather than flexion. A 4-level laminectomy and subsequent posterior stabilization with intra-articular screws was executed. At 3-mo follow up there was a regression of tetraparesis but motor deficits of the lower limbs residuated. At the same follow up postoperative MRI was executed. It suggested enlargement of the syrinx. Perhaps hyperintensity within spinal cord appeared "bounded" from C3 to C7 with clearer margins. At the level of surgical decompression, subarachnoid space and spinal cord enlargement were also evident. A review of the literature was executed using PubMed database. The objective of the research was to find an etiopathological theory able to relate syringomyelia with cervical spondylosis. Only 6 articles have been found. At the origin of syringomyelia the mechanisms of compression and instability are proposed. Perhaps other studies assert the importance of subarachnoid space regard cerebrospinal fluid (CSF) dynamic. We postulate that cervical spine instability may be the cause of multiple microtrauma towards spinal cord and consequently may damage spinal cord parenchyma generating myelomalacia and consequently syrinx. Otherwise the hemorrhage within spinal cord central canal can cause an obstruction of CSF outflow, finally generating the syrinx. On the other hand in cervical spondylosis the stenotic elements can affect subarachnoid space. These elements rubbing towards spinal cord during movements of the neck can generate arachnoiditis, subarachnoid hemorrhages and arachnoid adhesions. Analyzing the literature these "complications" of cervical spondylosis are described at the origin of syringomyelia. So surgical decompression, enlarging medullary canal prevents rubbings and contacts between the bone-ligament structures of the spine towards spinal cord and subarachnoid space therefore syringomyelia. Perhaps stabilization is also necessary to prevent instability of the cervical spine at the base of central cord syndrome or syringomyelia. Finally although patients affected by central cord syndrome are usually managed conservatively we advocate, also for them, surgical treatment in cases affected by advanced state of the symptoms and MRI.

Treatment of Syringomyelia Related to Nontraumatic Arachnoid Pathologies of the Spinal Canal

Disturbances of cerebrospinal fluid (CSF) flow are the commonest cause of syringomyelia. Spinal arachnopathies may lead to CSF flow obstructions but are difficult to diagnose. Consequently, associated syringomyelias are often categorized as idiopathic. To present and analyze the diagnosis of and long-term outcomes in an observational study of patients with nontraumatic arachnopathies from 1991 to 2011. A total of288 patients (mean age, 47 ± 15 years; follow-up, 54 ± 46 months) were evaluated. Decompression with arachnolysis, untethering, and duraplasty for restoration of CSF flow was recommended to patients with neurological progression. Neurological examinations, magnetic resonance images, and follow-up data were evaluated. Individual symptoms were analyzed during the first postoperative year, and long-term outcomes were analyzed with Kaplan-Meier statistics to determine rates of progression-free survival. In total,189 patients either refused an operation or were managed conservatively for lack of progression. Among 79 unoperated patients with follow-up information available for up to 8 years, 2 patients deteriorated. Ninety-nine patients with progressive symptoms underwent 116 operations: 108 decompressions and 8 other surgeries. Three months postoperatively, 53% considered their status improved and 37% were unchanged. In the long term, surgery on arachnopathies limited to 2 spinal segments was followed by progression-free survival for 78% over 10 years, in contrast to 31% with extensive arachnopathies. Surgery on nontraumatic arachnopathies related to syringomyelia should be reserved for patients with progressive symptoms. Arachnolysis, untethering, and duraplasty provide good long-term results for focal arachnopathies. For extensive pathologies with a history of subarachnoid hemorrhage or meningitis, treatment remains a major challenge.

Endoscope-Assisted Surgery of Spinal Intradural Adhesions in the Presence of Cerebrospinal Fluid Flow Obstruction

Prospective cohort study. To investigate whether the adjunctive use of endoscopy of the subarachnoid space (arachnoscopy) can improve the success of microsurgery for spinal arachnoid adhesions. Intradural adhesions that obstruct pulsatile cerebrospinal fluid (CSF) flow are a typical spinal cause of syringomyelia. Phase-contrast magnetic resonance imaging (MRI) allows CSF flow obstructions to be reliably localized. The treatment of choice is the microsurgical removal of CSF flow obstructions caused by adhesions. Microsurgery, however, does not lend itself to assessments of further adhesions beyond the borders of the exposed area. In this study, we therefore investigated whether endoscopic assistance allows adhesions in the vicinity of the exposed area to be detected. From 2006 to 2009, a single neurosurgeon performed 27 consecutive microsurgical procedures with endoscopic assistance in 25 patients with spinal arachnoid adhesions. A MurphyScope endoscope was used for this purpose. CSF flow was studied before and after surgery in all patients using phase-contrast MRI in the region of the craniocervical junction, the cervical spine, the thoracic spine, and the lumbar spine. In all 27 procedures, CSF flow obstructions were detected at the level identified by phase-contrast MRI. In 25 procedures, image quality was sufficient for an inspection of the adjacent subarachnoid space. In six cases, the surgeon detected further adhesions that obstructed CSF flow in the adjacent subarachnoid space not visualized with the microscope. In all cases, these adhesions were identified and removed during microsurgery.Postoperative MRI scans demonstrated free CSF flow in all patients and a decrease in syrinx size in six patients. Arachnoscopy is a helpful adjunct to microsurgery and can be performed safely and easily. It allows the surgeon to detect further adhesions in the subarachnoid space, which would remain undetected by microscopy alone.

The first description of Chiari I malformation with intuitive correlation between tonsillar ectopia and syringomyelia

Few are familiar with the neurological contributions of the German pathologist Theodor Langhans. Even fewer are aware of his significant and early contributions to the study of what is now known as the Chiari I malformation. In at least 4 cases, Langhans described the association between tonsillar ectopia and syringomyelia. Moreover, this early pioneer speculated that there was a cause and effect with hindbrain herniation resulting in improper flow at the craniocervical junction and consequent development of syringomyelia. These cases were reported prior to Hans Chiari's descriptions, and Langhans' theory of impeded foramen magnum flow as a cause of syringomyelia was novel and preceded the current understanding of this mechanism by almost a century. The authors discuss the life of Langhans and translate excerpts from his 1881 work regarding tonsillar ectopia and syringomyelia.

Fractional Anisotropy Levels Derived From Diffusion Tensor Imaging in Cervical Syringomyelia

Syringomyelia can result in major functional disability. Conventional imaging techniques frequently fail to detect the underlying cause of syringomyelia. The prediction as to whether syringomyelia might lead to neurological deficits is still challenging. We hypothesized that fractional anisotropy (FA) derived from diffusion tensor imaging (DTI) is a parameter to detect dynamic forms of syringomyelia. Six patients with cervical syringomyelia, all comparable in size, shape, and location, were examined, along with 2 volunteers. Patients underwent electrophysiological recordings (somatosensory evoked potentials, motor evoked potentials, silent periods). Magnetic resonance imaging (1.5 T) was performed with a 6-element spine coil. Anatomic images were acquired with a 3-dimensional, constructive interference in steady-state sequence, and DTI with an echo-planar imaging sequence (5-mm thickness, b value 800 s/mm) using the generalized autocalibrating partially parallel acquisitions technique. The positions were centered on the syrinx in the volunteers between the C2 and Th1. DTI data were interpolated to a spatial resolution of 0.5 mm. After calculation of a diffusion tensor in each pixel, an FA map was calculated and profiles of the FA values across the spinal cord were calculated in all slices. FA values were lower at the level of all examined syrinxes and reached normal values beyond them. Electrophysiological results correlated with the decrease in FA value. There were no presyrinx changes in the white matter tracts in terms of signs of FA changes beneath the syrinx. DTI of syringomyelia can demonstrate white matter fiber tracts around and beyond the syrinx consistent with electrophysiological values. DTI of the cervical spine can provide quantitative information about the pathological characteristics beyond the abnormalities visible on magnetic resonance imaging.

Spinal arteriovenous malformation associated with syringomyelia

The authors describe 4 cases of syringomyelia-associated spinal cord arteriovenous malformation (AVM). All cases were managed with embolization of the AVM. Treatments were aimed to stabilize the AVM itself and not directed toward the syrinx. In 3 of the 4 cases the syringomyelia resolved after treatment. Reports concerning AVM as a cause of syringomyelia is very scarce and lacks posttreatment clinical information. In light of the clinical course and imaging findings, the authors propose a theory that venous hypertension in the spinal cord is the trigger for the development of syringomyelia, which may reverse after AVM treatment.

Chiari‐Like Malformation with Syringomyelia in the Cavalier King Charles Spaniel: Long‐Term Outcome After Surgical Management

To evaluate long-term success of cranial cervical decompression for management of canine Chiari-like malformation with syringomyelia (CM/SM). Retrospective clinical study. Cavalier King Charles spaniels (n=15). After diagnosis by magnetic resonance imaging (MRI) dogs had cranial cervical decompression with durotomy. Seven dogs had the durotomy patched with biocompatible collagen matrix. Clinical outcome was monitored for >12 months. All dogs either improved (80%) or were unchanged (20%) postoperatively. Postoperative MRI in 6 dogs revealed persistence of syringomyelia. Seven dogs (47%) subsequently deteriorated, 0.2-2.3 years after surgery (mean, 1.3 years) and 2 dogs were eventually euthanatized as a consequence. Twelve dogs were still alive, 1-6.5 years after surgery (mean, 2.5 years). Cranial cervical decompression surgery is associated with low mortality and morbidity, and results in clinical improvement in most dogs. The procedure seemingly does not result in syrinx collapse and resolution. Clinical improvement may not be sustained and some dogs can be expected to deteriorate. Cranial cervical decompression surgery may have a role in management of CM/SM. In dogs with severe pain, it can improve quality of life for several years; however, it does not appear to adequately address the primary cause of syringomyelia. Further prospective study is needed to better understand the pathogenesis and treatment of this disorder. Because this condition causes neuropathic pain but does not necessarily result in euthanasia more information is needed on appropriate pain management for these patients.

黄色靭帯石灰化症に伴う脊髄空洞症の１例―ＰＶＩ，Ｒｏ測定による手術効果の検証―

Ossification of the yellow ligament (OYL) is considered an uncommon cause of syringomyelia, and single case has been described (11). We encountered simply 1 case of syringomyelia associated with cervical OYL out of more than 320 surgically treated syringomyelia cases.The 66-year-old female patient underwent cervical laminoplasty and displayed good postoperative course. Long-standing blockage of CSF circulation is considered one of the main factors for syringomyelia associated with degenerative disease of the cervical spine [2,3,4,5,6,7,10,11,15]. However this speculation warrants further discussion. We therefore obtained more dynamic and objective data using analytical methods described by Marmarou in 1975 [9]. The clinical course of this patient is discussed with reference to the literature and the results of a CSF dynamic study.