Little is known about the natural history of scoliosis found in patients with syringomyelia, including the factors affecting scoliosis curve progression and the effect of syrinx drainage treatment. Twenty patients having scoliosis with syringomyelia diagnosed by MRI were followed up for 6.6 (range 2.0–12.6) years on an average. Various factors potentially influencing curve pattern or progression in these patients were then retrospectively reviewed. The convex side of major curve of scoliosis tended to be on the same side as the syrinx and as the unilateral neurologic abnormality. No correlation was found between the location and the size of the syrinx and the location and size of the major curve of the scoliosis, or between the severity of neurologic deficit and the size of the major curve of the scoliosis. In patients under the age of ten at the time of diagnosis of scoliosis and with a flexible curve, decompression of the syrinx improved or stabilized scoliosis. In most patients over the age of ten, surgical treatment of the scoliosis was necessary because of the large initial size of the curve or progression of the curve even after syrinx drainage. Other factors including gender, location of the syrinx, type of the curve, and severity of neurologic deficits did not correlate with the progression of the curve. The results of this retrospective study suggest that early diagnosis and decompression of a syrinx in scoliosis patients especially under the age of ten is crucial and may decrease the curve size and limit scoliosis curve progression.
Scoliosis; Syringomyelia; MRI; Syrinx drainage
Syringomyelia is characterized by a fluid-filled cavity within the spinal cord. While its pathogenesis is currently debated, the relationship of syringomyelia with other conditions, such as Chiari I malformation and cord/column trauma, is well accepted. Despite these common associations, a nidus for syrinx formation has not been identified in a subset of patients. We report 2 patients with idiopathic cervicothoracic syringomyelia who presented with progressive neurologic dysfunction. Diagnostic and treatment algorithms used in the care of these patients are presented.
Retrospective review, including preoperative and postoperative studies, intraoperative findings, and the patients' surgical outcomes.
Patients underwent laminectomy, lysis of adhesions, untethering of spinal cord, fenestration of syrinx, and duraplasty after preoperative studies demonstrated evidence of focal cerebrospinal fluid flow block at the level of the syrinx. One patient's neurologic condition improved after surgery, whereas the other's remained unchanged without further deterioration; both showed radiographic decrease in the syrinx on immediate postoperative magnetic resonance imaging.
These 2 cases illustrate patients who develop a cervicothoracic syrinx in the absence of any trauma, infection, previous manipulation of the neuraxis, or malformations known to be associated with a syringomyelia. Whereas there is no consensus on the optimal management of these patients, the patients reported here experienced arrest in deterioration or improvement of their neurologic examination, making the identification of this condition important as a potentially reversible cause of neurologic deficits. Long-term follow-up is required to determine the efficacy, durability, and lifestyle impact of the procedure.
Spinal cord injuries; Syringomyelia; idiopathic; Syrinx; Arachnoiditis; Central subarachnoid stenosis
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.
Syringomyelia; Cervical spondylosis; Syringomyelia surgery; Syringomyelia etiology; Syringomyelia physiopathology
Chiari malformation Type I (CM-I) is a developmental abnormality often associated with a spinal syrinx. Patients with syringomyelia are known to have an increased risk of scoliosis, yet the influence of specific radiographically demonstrated features on the prevalence of scoliosis remains unclear. The primary objective of the present study was to investigate the relationship of maximum syrinx diameter and tonsillar descent to the presence of scoliosis in patients with CM-I–associated syringomyelia [AQ? Edit okay? If not, please advise. JG: edit correct]. A secondary objective was to explore the role of craniovertebral junction (CVJ) characteristics for additional risk factors for scoliosis.
The authors conducted a retrospective review of pediatric patients evaluated for CM-I with syringomyelia at a single institution in the period from 2000 to 2012. Syrinx morphology and CVJ parameters were evaluated with MRI, whereas the presence of scoliosis was determined using standard radiographic criteria. Multiple logistic regression was used to analyze radiological features that were independently associated with scoliosis.
Ninety-two patients with CM-I and syringomyelia were identified. The mean age was 10.5 ± 5 years. Thirty-five (38%) of 92 patients had spine deformity; 23 (66%) of these 35 were referred primarily for deformity, and 12 (34%) were diagnosed with deformity during workup for other symptoms. Multiple regression analysis revealed maximum syrinx diameter > 6 mm (OR 12.1, 95% CI 3.63–40.57, p < 0.001) and moderate (5–12 mm) rather than severe (> 12 mm) tonsillar herniation (OR 7.64, 95% CI 2.3–25.31, p = 0.001) as significant predictors of spine deformity when controlling for age, sex, and syrinx location.
The current study further elucidates the association between CM-I and spinal deformity by defining specific radiographic characteristics associated with the presence of scoliosis. Specifically, patients presenting with larger maximum syrinx diameters (> 6 mm) have an increased risk of scoliosis.
Chiari malformation; syringomyelia; scoliosis
Craniocervical decompression for Chiari malformation Type I (CM-I) and syringomyelia has been reported to fail in 10%–40% of patients. The present prospective clinical study was designed to test the hypothesis that in cases in which syringomyelia persists after surgery, craniocervical decompression relieves neither the physiological block at the foramen magnum nor the mechanism of syringomyelia progression.
The authors prospectively evaluated and treated 16 patients with CM-I who had persistent syringomyelia despite previous craniocervical decompression. Testing before surgery included the following: 1) clinical examination; 2) evaluation of the anatomy using T1-weighted MR imaging; 3) assessment of the syrinx and CSF velocity and flow using cine phase-contrast MR imaging; and 4) appraisal of the lumbar and cervical subarachnoid pressures at rest, during a Valsalva maneuver, during jugular compression, and following the removal of CSF (CSF compliance measurement). During surgery, ultrasonography was performed to observe the motion of the cerebellar tonsils and syrinx walls; pressure measurements were obtained from the intracranial and lumbar intrathecal spaces. The surgical procedure involved enlarging the previous craniectomy and performing an expansile duraplasty with autologous pericranium. Three to 6 months after surgery, clinical examination, MR imaging, and CSF pressure recordings were repeated. Clinical examination and MR imaging studies were then repeated annually.
Before reexploration, patients had a decreased size of the CSF pathways and a partial blockage in CSF transmission at the foramen magnum. Cervical subarachnoid pressure and pulse pressure were abnormally elevated. During surgery, ultrasonographic imaging demonstrated active pulsation of the cerebellar tonsils, with the tonsils descending during cardiac systole and concomitant narrowing of the upper pole of the syrinx. Three months after reoperation, patency of the CSF pathways was restored and pressure transmission was improved. The flow of syrinx fluid and the diameter of the syrinx decreased after surgery in 15 of 16 patients.
Persistent blockage of the CSF pathways at the foramen magnum resulted in increased pulsation of the cerebellar tonsils, which acted on a partially enclosed cervical subarachnoid space to create elevated cervical CSF pressure waves, which in turn affected the external surface of the spinal cord to force CSF into the spinal cord through the Virchow-Robin spaces and to propel the syrinx fluid caudally, leading to syrinx progression. A surgical procedure that reestablished the CSF pathways at the foramen magnum reversed this pathophysiological mechanism and resolved syringomyelia. Elucidating the pathophysiology of persistent syringomyelia has implications for its primary and secondary treatment.
syringomyelia; therapeutics; radiography; physiology; Arnold-Chiari malformation, Type I
First described in 1928, percutaneous aspiration of syringomyelia is infrequently performed to aid in diagnosis and surgical management. We describe a case of post traumatic syringomyelia successfully treated with direct fluoroscopic drainage with substantial resolution of syrinx-related neurologic symptoms.
The patient is a 36-year-old man involved in a motorcycle accident who sustained multiple vertebral fractures resulting in dense paraplegia below T4, ultimately treated with multilevel lami-nectomy and pedicle screw fixation. The patient began to experience phantom leg paresthesias and muscle spasm felt to be related to an extensive spinal cord syrinx extending to the conus.
Syrinx drainage was accomplished fluoroscopically at the level of the conus by percuntaneous needle drainage after cord localization with intrathecal myelographic contrast. Clear spinal fluid was drained from the syrinx cavity without complication. Immediately during and after drainage, the patient recognized a decrease in phantom pelvic and lower extremity paresthesias with significantly reduced spasticity. Syrinx collapse was documented with post-drainage CT imaging. Sustained relief of paresthesias and muscle spasms was achieved with gradual syrinx and symptom return requiring subsequent drainages performed at nine, 22 and 37 months following the initial drainage.
In addition to confirming the symptomatic nature of syringomyelia in those with atypical symptoms, fluoroscopically guided drainage of syrinx can in select instances provide sustained relief.
This modality may have additional advantages including serving as an adjunctive maneuver to improve operative access to the subarachnoid space by collapsing the cord, and serving as a temporizing measure for those patients who are poor surgical candidates. Maneuvers such as fluoroscopic table angulation provide an additional benefit in both the localization and drainage of syringomyelia and thus may be preferred over other minimally invasive procedures such as CT-guided drainage.
syringomyelia, syrinx, fluoroscopy, percutaneous drainage
The pathogenesis of syringomyelia in patients with an associated spinal lesion is incompletely understood. The authors hypothesized that in primary spinal syringomyelia, a subarachnoid block effectively shortens the length of the spinal subarachnoid space (SAS), reducing compliance and the ability of the spinal theca to dampen the subarachnoid CSF pressure waves produced by brain expansion during cardiac systole. This creates exaggerated spinal subarachnoid pressure waves during every heartbeat that act on the spinal cord above the block to drive CSF into the spinal cord and create a syrinx. After a syrinx is formed, enlarged subarachnoid pressure waves compress the external surface of the spinal cord, propel the syrinx fluid, and promote syrinx progression.
To elucidate the pathophysiology, the authors prospectively studied 36 adult patients with spinal lesions obstructing the spinal SAS. Testing before surgery included clinical examination; evaluation of anatomy on T1-weighted MRI; measurement of lumbar and cervical subarachnoid mean and pulse pressures at rest, during Valsalva maneuver, during jugular compression, and after removal of CSF (CSF compliance measurement); and evaluation with CT myelography. During surgery, pressure measurements from the SAS above the level of the lesion and the lumbar intrathecal space below the lesion were obtained, and cardiac-gated ultrasonography was performed. One week after surgery, CT myelography was repeated. Three months after surgery, clinical examination, T1-weighted MRI, and CSF pressure recordings (cervical and lumbar) were repeated. Clinical examination and MRI studies were repeated annually thereafter. Findings in patients were compared with those obtained in a group of 18 healthy individuals who had already undergone T1-weighted MRI, cine MRI, and cervical and lumbar subarachnoid pressure testing.
In syringomyelia patients compared with healthy volunteers, cervical subarachnoid pulse pressure was increased (2.7 ± 1.2 vs 1.6 ± 0.6 mm Hg, respectively; p = 0.004), pressure transmission to the thecal sac below the block was reduced, and spinal CSF compliance was decreased. Intraoperative ultrasonography confirmed that pulse pressure waves compressed the outer surface of the spinal cord superior to regions of obstruction of the subarachnoid space.
These findings are consistent with the theory that a spinal subarachnoid block increases spinal subarachnoid pulse pressure above the block, producing a pressure differential across the obstructed segment of the SAS, which results in syrinx formation and progression. These findings are similar to the results of the authors' previous studies that examined the pathophysiology of syringomyelia associated with obstruction of the SAS at the foramen magnum in the Chiari Type I malformation and indicate that a common mechanism, rather than different, separate mechanisms, underlies syrinx formation in these two entities. Clinical trial registration no.: NCT00011245. (http://thejns.org/doi/abs/10.3171/2012.8.SPINE111059)
syringomyelia; physiology; ultrasonography; surgery; cerebrospinal fluid; magnetic resonance imaging; myelography
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.
Key words Chiari malformation; Foramen magnum decompression; Syringomyelia; Syringosubarachnoid shunt
Objective: The pathophysiology of arachnoiditis ossificans (AO) and its association with syringomyelia remains a rare and poorly understood phenomenon. Here, we present a case of AO associated with syringomyelia, a review of literature, and a discussion of current understanding of disease pathophysiology.
Methods: A literature review was performed using MEDLINE (January 1900–May 2010) and Embase (January 1900–May 2010) to identify all English-language studies that described AO with syringomyelia. The current report was added to published cases.
Results: Over 50 cases of AO are reported in literature, of which only eight are associated with syringomyelia. The various presumptive etiologies of syrinx formation include abnormalities in blood circulation, ischemia, hydrodynamic alternations in cerebrospinal fluid (CSF) flow, tissue damage, or incidental coexistence. Changing CSF dynamics related to decreased compliance of the subarachnoid space and subsequent paracentral dissection of the spinal cord may be implicated in the disease process. magnetic resonance imaging (MRI) scanning may identify the syrinx but fail to diagnose the calcified arachnoid. Five patients, including the current case, improved clinically following laminectomy and decompression.
Conclusions: Syringomyelia in association in AO is a rare phenomenon. A high index of suspicion is required and both MRI and computed tomography (CT) are recommended for diagnosis. The pathophysiology of syringomyelia in AO remains an area of ongoing research.
We report two unusual cases of a 17-month-old boy with a previously undiagnosed lumbar dermal sinus tract terminating in an intradural dermoid cyst and holocord edema or syrinx, presenting with paraparesis and sphincter dysfunction secondary to an intramedullary abscess and a 26-month-old boy with a previously undiagnosed lumbar dermal sinus tract terminating in an infected dermoid cyst and intramedullary abscess, presenting with recurrent episodes of meningitis and hydrocephalus. Pre-operative magnetic resonance imaging (MRI) studies in these patients were initially confused for an intramedullary spinal cord tumor; however, the presence of an associated dermal sinus tract made this diagnosis of neoplasm less likely. Total excision of the dermal sinus tract, debulking of the dermoid cyst and drainage of the intramedullary abscess through an L1-L5 osteoplastic laminoplasty and midline myelotomy, followed by long-term antibiotic therapy resulted in a good functional recovery. Post-operative MRI of the spine showed removal of the dermoid cyst, decreased inflammatory granulation tissue and resolution of the holocord edema or syrinx. We also performed a literature review to determine the cumulative experience of management of intramedullary abscess in this rare clinical setting.
Dermal sinus tract; dermoid cyst; intramedullary abscess; magnetic resonance imaging
There are few researches that demonstrate the relationship between the extent of syringomyelia and sagittal alignment of the cervical spine. The purpose of this study is to investigate the correlation between the change of syrinx size and cervical alignment.
From January 2001 to June 2008, we operated on 207 patients who had syringomyelia. The associated diseases were categorized by Chiari I malformation, tumor, trauma, spinal stenotic lesion, inflammatory disease and idiopathic causes. Thirty patients who had Chiari I malformation associated with syringomyelia and who underwent foramen magnum decompression (FMD), participated in this study. We excluded patients with scoliosis, cervical instrumentation, tumor, trauma, myelomeningocele, hydrocephalus, tethered cord and congenital vertebral anomalies. Lateral radiographs in neutral and magnetic resonance imaging were taken pre- and postoperatively.
Mean follow-up was 6.5 ± 1.5 years (ranged from 4.0 to 9.5 years). The mean pre- and postoperative lordosis angles at C2–C7 were −5.9° ± 1.0° and −10.4° ± 1.0°, respectively (P = 0.001). There was significant correlation between the differences of syrinx width and the cervical lordotic angles before and after surgery (P = 0.016). After FMD, syringomyelia and cervical alignment improved in 28 (93.3 %) and 25 (85.18 %) of 30 patients, respectively. There was significant correlation between recovery rate by Japanese Orthopaedic Association scores and the difference of the cervical lordotic angles before and after surgery (P = 0.022).
The present results demonstrate that the decrease of syrinx size by FMD may restore the cervical lordosis. We suggest that the postoperative cervical alignment might be a predictive factor for neurological outcome.
Cervical spinal alignment; Chiari malformation; Foramen magnum decompression; Syringomyelia
Ventriculoperitoneal (VP) shunt malfunction commonly presents as raised intracranial pressure. Rarely, when the central canal of the spinal cord communicates with the 4th ventricle, shunt malfunction can present as an expanding syrinx. The diagnosis is often delayed, resulting in severe morbidity. Some of these patients undergo repeated syrinx surgeries without much benefits. We report a case of chronic tuberculous meningitis with shunt malfunction presenting as an expanding spinal canal syrinx and quadriparesis. Fourth ventricular communication with syrinx was demonstrated with the help of a contrast ventriculogram. After shunt revision, syrinx resolved completely and the patient made significant improvement in his neurological deficits. The present case illustrates that a historical and rarely used investigation like contrast ventriculogram aids in the diagnosis and management even in the current neurosurgical practice. All patients with late onset syrinx and a previous VP shunt need to be investigated for shunt malfunction before considering syrinx surgery. A simple shunt revision resolves the syrinx in such conditions and avoids more complex procedures like Foramen magnum decompression. Relevant literature has been reviewed; pathophysiology and management options have been discussed.
Arachnoiditis; chronic meningitis; communicating central canal syrinx; contrast ventriculogram; syringomyelia; ventriculoperitoneal shunt malfunction
Delayed Chiari malformation with syringomyelia is an uncommon and sparsely reported complication after lumbar cisternal shunting. A number of treatments have been implemented with varying degrees of success. After review of these modalities, a treatment plan was devised and implemented.
A 15-year-old girl was diagnosed with idiopathic intracranial hypertension (pseudotumor cerebri) and had placement of a Medtronic Spetzler lumboperitoneal shunt. She did well for 10 years and then developed a 3-week history of headache, balance problems, and sensory loss. Workup demonstrated a new Chiari malformation and cervical syrinx. She underwent initial placement of a ventriculoperitoneal shunt, followed by ligation of the lumboperitoneal shunt. She then had a suboccipital decompression and duraplasty. Follow-up at 6 months showed relief of her symptoms and MRI demonstrated resolution of the Chiari malformation and syrinx.
Delayed Chiari malformation and/or syringomyelia after lumbar shunting is best treated with placement of a ventricular device and ligation of the lumbar shunt. The Chiari malformation and/or syrinx should be surgically addressed for persistent symptoms or progression of the structural abnormality.
Acquired chiari malformation; idiopathic intracranial hypertension; lumboperitoneal shunt; pseudotumor cerebri; syringomyelia
Various surgical procedures for the treatment of post-traumatic syringomyelia have been introduced recently, but most surgical strategies have been unreliable. We introduce the concept and technique of a new shunting procedure, syringo-subarachnoid-peritoneal shunt. A 54-year-old patient presented to our hospital with a progressive impairment of motion and position sense on the right side. Sixteen years before this admission, he had been treated by decompressive laminectomy for a burst fracture of L1. On his recent admission, magnetic resonance (MR) imaging studies of the whole spine revealed the presence of a huge syrinx extending from the medulla to the L1 vertebral level. We performed a syringo-subarachnoid-peritoneal shunt, including insertion of a T-tube into the syrinx, subarachnoid space and peritoneal cavity. Clinical manifestations and radiological findings improved after the operation. The syringo-subarachnoid-peritoneal shunt has several advantages. First, fluid can communicate freely between the syrinx, the subarachnoid space, and the peritoneal cavity. Secondly, we can prevent shunt catheter from migrating because dural anchoring of the T-tube is easy. Finally, we can perform shunt revision easily, because only one arm of the T-tube is inserted into the intraspinal syringx cavity. We think that this procedure is the most beneficial method among the various shunting procedures.
Syringomyelia; Spinal cord injury; Shunt
Aquaporin-4 (AQP4) is an astroglial water channel protein that plays an important role in the transmembrane movement of water within the central nervous system. AQP4 has been implicated in numerous pathological conditions involving abnormal fluid accumulation, including spinal cord edema following traumatic injury. AQP4 has not been studied in post-traumatic syringomyelia, a condition that cannot be completely explained by current theories of cerebrospinal fluid dynamics. Alterations of AQP4 expression or function may contribute to the fluid imbalance leading to syrinx formation or enlargement. The aim of this study was to examine AQP4 expression levels and distribution in an animal model of post-traumatic syringomyelia. Immunofluorescence and western blotting were used to assess AQP4 and glial fibrillary acidic protein (GFAP) expression in an excitotoxic amino acid/arachnoiditis model of post-traumatic syringomyelia in Sprague-Dawley rats. At all time-points, GFAP-positive astrocytes were observed in tissue surrounding syrinx cavities, although western blot analysis demonstrated an overall decrease in GFAP expression, except at the latest stage investigated. AQP4 expression was significantly higher at the level of syrinx at three and six weeks following the initial syrinx induction surgery. Significant increases in AQP4 expression also were observed in the upper cervical cord, rostral to the syrinx except in the acute stage of the condition at the three-day time-point. Immunostaining showed that AQP4 was expressed around all syrinx cavities, most notably adjacent to a mature syrinx (six- and 12-week time-point). This suggests a relationship between AQP4 and fluid accumulation in post-traumatic syringomyelia. However, whether this is a causal relationship or occurs in response to an increase in fluid needs to be established.
aquaporin-4; post-traumatic syringomyelia; spinal cord injury
Description of syrinx resolution after posterior fossa decompression (PFD) in patients with scoliosis secondary to Chiari malformation type I (CMI) and syringomyelia (SM) has been rarely reported in the literature. This study was performed to investigate the outcome of PFD in patients with scoliosis secondary to CMI and to identify potential predictive factors for better outcome after PFD.
Material and methods
Patients with scoliosis secondary to CMI and SM, who had undergone PFD during the period 2000 through 2009, were recruited. Inclusion criteria were (1) age ≤ 18 years, (2) diagnosis of SM associated with CMI, (3) scoliosis as the first complaint, (4) having undergone preoperative and follow-up magnetic resonance imaging (MRI). Patients with acquired CMI anomalies or who had received syringosubarachnoid shunting were excluded. The maximal S/C ratio and syrinx length were measured to evaluate syrinx resolution after PFD. A 20% decrease in S/C ratio or length at the latest follow-up was defined as a significant radiographic improvement and complete resolution was used to describe the syrinx disappearing after PFD.
44 patients were recruited. Follow-up MRI was conducted for all 44 patients at 6 ± 3 months postoperatively, for 37 patients at 2 years ± 3 months, for 26 patients at 4 years ± 3 months, and for 15 patients at 6 years ± 3 months. 97.7% (43 of 44) of patients showed significant radiographic improvement by MRI. The distance of tonsillar descent (mm) was correlated significantly with the surgical outcome (r = 0.116, P = 0.013). Significant improvement was observed within 6 months postoperatively, with continued slow improvement after that.
Syringes showed significant improvement after PFD in most patients with scoliosis secondary to CMI. Resolution generally occurred within 6 months follow-up and continued at a slow rate for several years. In addition, the severity of tonsillar descent is a potential predictor for better improvement after standard PFD.
Resolution; Syrinx; Chiari malformation type I; Syringomyelia; Scoliosis; Posterior fossa decompression
Idiopathic hemorrhage in a syrinx is a rare entity known as Gowers’ intrasyringeal hemorrhage. Bleeding confined to the syrinx cavity causes severe, sometimes acute, neurological deficits. We report a case of intrasyringeal hemorrhage into a preexisting lumbosacral syrinx associated with Chiari type I malformation.
A 39-year-old female with Noonan syndrome underwent foramen magnum decompression and a cervical syrinx-subarachnoid shunt for Chiari type I malformation-associated syringomyelia 7 years ago. She presented progressive gait deterioration and acute urinary dysfunction, indicating conus medullaris syndrome. Initial magnetic resonance imaging revealed massive hemorrhage in the intrasyringeal cavity of the conus medullaris. The patient underwent surgical removal of the intrasyringeal hematoma and her neurological symptoms improved postoperatively.
Although Gowers’ intrasyringeal hemorrhage is rare, this entity should be taken into consideration in patients with syringomyelia showing acute neurological deterioration.
Chiari type I malformation; intrasyringeal hemorrhage; Noonan syndrome; spinal disease; syringomyelia
This study sought to quantify the frequency of previously unidentified spinal cord anomalies identified by routine preoperative magnetic resonance imaging (MRI), in patients planned for surgical scoliosis correction.
Our study group comprised 206 patients with idiopathic scoliosis who underwent deformity correction from 1998 to 2008. Clinical records of all the patients were retrospectively reviewed to ascertain the proportion having a neural abnormality on preoperative MRI scan.
Twenty of 206 patients (9.7 %) were diagnosed with an unexpected intraspinal anomaly on routine preoperative MRI. In all cases, a neurosurgical opinion was sought prior to further intervention. Of the 20 patients, 11 underwent a neurosurgical procedure (de-tethering of cord, decompression of Chiari, decompression of syrinx). There was no statistically significant difference between the group of patients who had intrinsic spinal cord anomalies on preoperative MRI and those did not have a cord abnormality with regard to age at presentation, gender, side of dominant curve and degree of curve (p < 0.05).
The high frequency of spinal cord abnormalities unidentified by preoperative neurological examination, and the frequent need for subsequent neurosurgical intervention, suggests that MRI assessment prior to deformity correction is important in the management of idiopathic scoliosis.
Idiopathic scoliosis; Intraspinal anomalies; Preoperative MRI
Guillain-Barre syndrome (GBS) and syringomyelia are diseases of different entities. GBS is an acute post-infectious autoimmune disease which is mediated by autoantibodies against the myelin of peripheral nerves. Syringomyelia is a chronic disease characterized by a cavity extending longitudinally inside the spinal cord. A 67-year-old man is being hospitalized due to severe numbness and ascending weakness in all limbs. On neurological examination, the motor power of all limbs are decreased and show absence of deep tendon reflexes (DTRs). The patient is being diagnosed with GBS on the basis of the acute clinical course, nerve conduction studies of segmental demyelinating polyneuropathy, and a finding of albuminocytologic dissociation in the cerebrospinal fluid. The patient is presented with a new set of symptoms thereafter, which composes of sensory changes in the upper extremities, the urinary dysfunction including frequency and residual urine, spastic bilateral lower extremities, and increased reflexes of the knee and the biceps at follow-up examinations. The spinal magnetic resonance imaging in the sagittal section revealed a syrinx cavity between the fifth cervical and the first thoracic vertebral segment in the cord. The somatosensory evoked potential show sensory pathway defects between both the brachial plexus and the brain stem. Thus, this patient is being diagnosed with both GBS and syringomyelia. We report a case of symptomatic syringomyelia coexisting with GBS. Since the GBS is presented with a progressive muscle weakness and reduced DTRs, the muscle weakness and stiffness in the extremities suggests a concurrent syringomyelia might be easily overlooked.
Guillain-Barre syndrome; Syringomyelia; Posttraumatic syringomyelia
The natural history of Chiari I malformation in children remains unclear.
In this population-based retrospective cohort study, we searched radiology reports from all head and spine MRI scans (n=5248) performed among 741, 815 children under age 20 within Kaiser Northern California, 1997–1998, for Chiari I. We reviewed medical records and imaging studies to determine clinical and radiographic predictors of significant neurologic symptoms defined as moderate to severe headache, neck pain, vertigo or ataxia.
The 51 patients identified with Chiari I represented 1% of children who had head or spine MRI scans performed during the study period. Headache (55%) and neck pain (12%) were the most common symptoms. Syringomyelia was present in 6 patients (12%) at time of initial diagnosis; no new syrinxes developed during follow-up. Older age at time of diagnosis was associated with increased risk of headache (OR 1.3, 95% CI 1.1–1.5) and significant neurologic symptoms (OR 1.2, 95% CI 1.04–1.4).
Chiari I, an under-recognized cause of headaches in children, is also frequently discovered incidentally in children without symptoms. Larger and longer-term studies are needed to determine the prognosis and optimal treatment of pediatric Chiari I.
Posttraumatic syringomyelia may result from a variety of inherent conditions and traumatic events, or from some combination of these. Many hypotheses have arisen to explain this complex disorder, but no consensus has emerged. A 28-year-old man presented with progressive lower extremity weakness, spasticity, and decreased sensation below the T4 dermatome five years after an initial trauma. Magnetic resonance imaging (MRI) revealed a large, multi-septate syrinx cavity extending from C5 to L1, with a retropulsed bony fragment of L2. We performed an L2 corpectomy, L1-L3 interbody fusion using a mesh cage and screw fixation, and a wide decompression and release of the ventral portion of the spinal cord with an operating microscope. The patient showed complete resolution of his neurological symptoms, including the bilateral leg weakness and dysesthesia. Postoperative MRI confirmed the collapse of the syrinx and restoration of subarachnoid cerebrospinal fluid (CSF) flow. These findings indicate a good correlation between syrinx collapse and symptomatic improvement. This case showed that syringomyelia may develop through obstruction of the subarachnoid CSF space by a bony fracture and kyphotic deformity. Ventral decompression of the obstructed subarachnoid space, with restoration of spinal alignment, effectively treated the spinal canal encroachment and post-traumatic syringomyelia.
Syringomyelia; Magnetic resonance imaging; Trauma; Subarachnoid space; Obstruction
Study Design Systematic review.
Study Rationale One of the most consistent indications for a Chiari decompression is tonsillar descent meeting the radiographic criteria and an associated syrinx in a symptomatic patient. In counseling patients about surgery, it would be advantageous to have information regarding the expected outcome with regard to the syrinx and other possible treatments available if the result is suboptimal.
Clinical Questions The clinical questions include: (1) What is the average rate of recurrent or residual syringomyelia following posterior fossa decompression as a result of Chiari malformation with associated syringomyelia? (2) What treatment methods have been reported in the literature for managing recurrent or residual syringomyelia after initial posterior fossa decompression?
Materials and Methods Available search engines were utilized to identify publications dealing with recurrent or residual syrinx after Chiari decompression and/or management of the syrinx. Rates of residual or recurrent syrinx were extracted and management strategies were recorded. Overall strength of evidence was quantified.
Results Of the 72 citations, 11 citations met inclusion criteria. Rates of recurrent/residual syringomyelia after decompression in adults range from 0 to 22% with an average of 6.7%. There were no studies that discussed specifically management of the remaining syrinx.
Conclusion Rates of recurrent/residual syringomyelia after Chiari decompression in adults range from 0 to 22% (average 6.7%). Although no studies describing the optimal management of residual syrinx were found, there is general agreement that the aim of the initial surgery is to restore relatively unimpeded flow of cerebrospinal across the craniocervical junction. Large holocord syrinx may induce a component of spinal cord injury even with adequate decompression and reduction in the caliber of the syrinx, resulting in permanent symptoms of injury.
Chiari decompression; residual syrinx
OBJECTIVE--To determine the incidence of clinically diagnosable post-traumatic syringomyelia (PTS). METHODS--A population of 815 consecutive patients with traumatic spinal cord injuries was studied between January 1990 and December 1992. RESULTS--Reviews of all records, full clinical evaluation, and thorough neurological examination of all patients disclosed 28 patients in whom PTS was confirmed radiologically (3.43%). The incidence of the presenting symptoms, including bladder dysfunction, is described. The level and density of cord lesion was correlated with incidence and it was found that posttraumatic syringomyelia was twice as common in patients with complete injuries than in patients with incomplete injuries. The highest incidence was found in patients with complete dorsal and complete dorsolumbar injuries. The interval between injury and diagnosis ranged from six months to 34 years (mean 8.6 years). This interval was shortest in patients with complete dorsal and incomplete cervical and dorsolumbar cord injuries. CONCLUSIONS--Reduction of the size of the syrinx seen on postoperative MRI correlated well with a satisfactory clinical outcome in 85% of patients.
Spinal hemangioblastomas (HB) are rare, histologically benign, highly vascularized tumors often associated with von Hippel–Lindau (VHL) disease. The aim of the current study is to demonstrate the benefit of early surgical resection of large spinal HBs in selected asymptomatic patients with VHL.
Seventeen patients underwent microsurgical resection of 20 spinal HBs at the Department of Neurosurgery at Helsinki University Central Hospital (HUCH). Thirteen tumors were in the cervical spine, five in thoracic and one patient had two lumbar lesions. MRI tumor showed an associated syrinx in 16 patients (94%). Tumor volume ranged from 27 to 2730 mm3. Out of 17 patients, 11 (65%) tested positive for VHL in mutation analysis. Five of these patients with tumors ranging from 55 to 720 mm3 were treated prophylactically.
Complete tumor resection was performed in 16 patients (94%) who were followed up for a median of 57 months (range 2–165 months). No patient had neurological decline on long-term follow-up. Among the patients with VHL, five patients with preoperative sensorimotor deficits showed improvement of their symptoms but never regained full function. One patient who presented with tetraplegia remained the same. Otherwise, all five patients with prophylactic surgery remained neurologically intact.
Although documented growth on serial MRIs and the need for pathological diagnosis have been suggested as indications for surgery in otherwise asymptomatic patients, our series showed that a potentially larger group of asymptomatic patients with spinal HB associated with VHL would benefit from microsurgical resection. Long-term results of the surgical management of spinal HB are generally favorable. Our results suggest staging and early treatment for spinal HB larger than 55 mm3, especially in patients with VHL. Small spinal HBs may be followed up.
Spinal cord; spinal hemangioblastoma; McCormick classification; microsurgery; von Hippel–Lindau
Although the demyelinating disease is not among the routine neurosurgery practices, it has been creating serious challenges for neurosurgeons both in diagnostic and surgical procedures for a long time.
Pathologically, they are similar to grade II glioma– oligodendroglioma or mixed gliomas. In the neurosurgical context, they are large and solitary lesion mimicking metastasis – lymphoma and brain abscesses. Because of these characteristics, medical literatures show that several cases of demyelinating disease have been surgically treated.
Diagnosis and Treatment approach:
For an efficient differential diagnosis of demyelinating disease using neuroimaging techniques such as magnetic resonance imaging (MRI) different types of information should be available such as the age of patient, previous medical history as well as physical examination. T2- hyperintensity of demyelinating plaques – ovoid lesions with main axes perpendicular to corpus callosum (called Dawson’s fingers) and (open ring shaped) an incomplete peripheral enhancing with the gap facing towards the brain surface all are imaging signs of the presence of demyelinating disease.
Furthermore, in spinal cord any expanding lesion even with syrinx should be considered in differential diagnosis of Multiple Sclerosis (MS), particularly in aggressive demyelinating diseases common in Asian countries. All of the above mentioned points are discussed in detail in this study.
Multiple sclerosis, Demyelinating disease, Neurosurgery, Differential diagnosis