Syringopleural shunt as a rescue procedure in patients with syringomyelia refractory to restoration of cerebrospinal fluid flow

Delayed spinal arachnoiditis with syringomyelia following aneurysmal subarachnoid haemorrhage: a case report with patient experience

BACKGROUND AND IMPORTANCE

Syringomyelia, or the formation of fluid-filled cysts within the spinal cord, associated with delayed spinal arachnoiditis is an uncommon complication of aneurysmal subarachnoid haemorrhage. To date, about 18 cases have been reported in medical literature, with just two reported in patients under the age of 35 years.

CLINICAL PRESENTATION

A 27-year-old female patient complained of sudden, severe headaches in the occipital region, nuchal rigidity, and drowsiness when she presented at our institution. A head computed tomography scan revealed intraventricular bleeding in the lateral and fourth ventricles with more extensive haemorrhaging in the frontal horns. A left posterior inferior cerebellar artery (PICA) aneurysm was confirmed via digital subtraction angiogram, and endovascular embolization was done. Two years later, the patient reported intense pain in the lower back along with symptoms suggestive of spinal cord compression. Spinal magnetic resonance imaging (MRI) showed spinal adhesions from C1 to L4, syringomyelia with some vasogenic oedema extending from T3 to T9 level, and a cyst in the lumbar region. Consequently, a right hemilaminectomy was performed along with microsurgical release of arachnoid adhesions and placement of a subdural drain. Radiological and symptomatic improvements were observed. Since then, the patient's clinical condition has remained stable during the past three years of follow-up visits.

CONCLUSIONS

Literature on optimal treatment modalities and patient prognosis is scarce and debated. The time for symptom improvement depends on the level and extent of spinal cord involvement. Rehabilitation may be required for most patients, as complete symptomatic recovery may not be attainable.

Does long segment subarachnoido-subarachnoid shunt prevent posttraumatic and postinfectious spinal arachnoid cyst recurrence?: technical note and case series

Syringomyelia associated with extensive spinal adhesive arachnoiditis (SAA) can be defined as a rare but progressive disease with potentially devastating clinical consequences. Diagnosis can be challenging due to the absence of specific clinical findings, confusion with other pathologies, and late imaging modalities. The treatment strategy for syringomyelia associated with extensive SAA should include direct drainage of the syringomyelia, and dissection of the adhesive arachnoid with expansive duraplasty. Hence, several approaches have been reported for arachnoid dissection and decompression of the subarachnoid space. The high risk of recurrence after the operation is one of the most challenging situations. First two cases were operated previously, and the cyst walls were removed and anastomosed to the intact subarachnoid space at the upper and lower ends by each other. However, in both cases, the cyst recurred after a short time and they were anastomosed again in our clinic. A subarachnoid-subarachnoid shunt was placed with a multi-hole silicone tube extending to the proximal and distal intact subarachnoid spaces and passing through the cyst removal area. In our third case, the shunt system we described was applied directly, and satisfactory results were obtained in the clinical follow-up of the patient. It has been demonstrated that subarachnoido-subarachnoid shunt is a very satisfactory treatment option for this type of pathology, which is difficult to follow and treat.

The Physiological Occlusion of the Central Canal May Be a Prerequisite for Syringomyelia Formation

OBJECTIVE

Syringomyelia is a common central nervous system disease characterized by the dilation of the central canal (CC). Regarding the pathogenesis of syringomyelia, cerebrospinal fluid (CSF) circulation obstruction in the subarachnoid space (SAS) of the spinal cord has been widely accepted. However, clinical and animal studies on obstructing the CSF in SAS failed to form syringomyelia, challenging the theory of SAS obstruction. The precise pathogenesis remains unknown.

METHODS

We utilized an extradural compression rat model to investigate the pathogenesis underlying syringomyelia. Magnetic resonance imaging enabled detection of syringomyelia formation. To assess CSF flow within the SAS, Evans blue was infused into the cisterna magna. Histological analysis allowed morphological examination of the CC. Furthermore, CSF flow through the CC was traced using Ovalbumin Alexa-Flour 647 conjugate (OAF-647). Scanning electron microscopy (SEM) enabled visualization of ependymal cilia.

RESULTS

The findings showed that the dura mater below the compression segment exhibited lighter coloration relative to the region above the compression, indicative of partial obstruction within the SAS. However, the degree of SAS occlusion did not significantly differ between syringomyelia (SM-Y group) and those without (SM-N group). Intriguingly, hematoxylin and eosin staining and CSF tracing revealed occlusion of the CC accompanied by reduced CSF flow in the SM-Y group compared to SM-N and control groups. SEM images uncovered impairment of ependymal cilia inside the syringomyelia.

CONCLUSION

CC occlusion may represent a physiological prerequisite for syringomyelia formation, while SAS obstruction serves to initiate disease onset. The impairment of ependymal cilia appears to facilitate progression of syringomyelia.

Syringopleural shunt for refractory syringomyelia: how I do it

BACKGROUND

Surgical treatment of syringomyelia is directed at the reconstruction of the subarachnoid space and restoration normal cerebrospinal fluid flow. Direct intervention on the syrinx is a rescue procedure and should be offered to patients with refractory syringomyelia.

METHODS

We provide an overview on indications and technique of syringopleural shunt (SPS). The procedure involves the connection of syrinx with the pleural space using a lumboperitoneal shunt. The occurrence of a negative pressure inside the pleural compartment offers an appropriate gradient for drainage from the syrinx.

CONCLUSIONS

The SPS allows for a safe and effective treatment of persistent syringomyelia when management of the underlying cause does not yield substantial improvement.

Intraoperative Neurophysiological Monitoring in Syringomyelia Surgery: A Multimodal Approach

Syringomyelia can be associated with multiple etiologies. The treatment of the underlying causes is first-line therapy; however, a direct approach to the syrinx is accepted as rescue treatment. Any direct intervention on the syrinx requires a myelotomy, posing a significant risk of iatrogenic spinal cord (SC) injury. Intraoperative neurophysiological monitoring (IONM) is crucial to detect and prevent surgically induced damage in neural SC pathways. We retrospectively reviewed the perioperative and intraoperative neurophysiological data and perioperative neurological examinations in ten cases of syringomyelia surgery. All the monitored modalities remained stable throughout the surgery in six cases, correlating with no new postoperative neurological deficits. In two patients, significant transitory attenuation, or loss of motor evoked potentials (MEPs), were observed and recovered after a corrective surgical maneuver, with no new postoperative deficits. In two cases, a significant MEP decrement was noted, which lasted until the end of the surgery and was associated with postoperative weakness. A transitory train of neurotonic electromyography (EMG) discharges was reported in one case. The surgical plan was adjusted, and the patient showed no postoperative deficits. The dorsal nerve roots were stimulated and identified in the seven cases where the myelotomy was performed via the dorsal root entry zone. Dorsal column mapping guided the myelotomy entry zone in four of the cases. In conclusion, multimodal IONM is feasible and reliable and may help prevent iatrogenic SC injury during syringomyelia surgery.

Surgical Management of Lumbar Adhesive Arachnoiditis Postmeningitis: A Bermuda Triangle?—Case Report and Review of Literature

Spinal arachnoiditis can occur as a delayed sequel of meningitis. Cerebrospinal fluid flow disturbances and adhesive loculations can cause cord compression and traction on roots causing the symptoms. The surgical treatment of this condition is often considered a limited option, because of the high chances of recurrence of symptoms and adhesions, often considered as surgical failure. Here, we report a patient with extensive lumbar–sacral adhesive arachnoiditis successfully treated with limited adhesiolysis under neuromonitoring and cystoperitoneal shunt placement.

Chiari Type 1 Malformation and Syringomyelia in Children: Classification and Treatment Options

Chiari type 1 malformation (CIM) is defined as tonsillar ectopia of >5 mm, while syringomyelia (SM) is defined as a cerebrospinal fluid (CSF)-filled cavity larger than 3 mm dissecting the spinal cord. Over the last decades, our understanding of these pathologies has grown; however, many controversies still exist almost in every aspect of CIM and SM, including etiology, indication for treatment, timing of treatment, surgical technique, follow-up regime, and outcome. This chapter provides a comprehensive overview on different aspects of CIM and SM and on the still existing controversies, based on the evidence presently available. Future directions for clinical research concerning CIM and SM treatment and outcome are elaborated and discussed as well.

A Clinical Study on the Treatment of Recurrent Chiari (Type I) Malformation with Syringomyelia Based on the Dynamics of Cerebrospinal Fluid

Objective. Combining the dynamics of cerebrospinal fluid, our study investigates the clinical effects of syringomyelia after the combination of fourth ventricle-subarachnoid shunt (FVSS) for recurrent Chiari (type I) malformations after cranial fossa decompression (foramen magnum decompression (FMD)). Methods. From December 2018 to December 2020, 15 patients with recurrent syringomyelia following posterior fossa decompression had FVSS surgery. Before and after the procedure, the clinical and imaging data of these individuals were retrospectively examined. Results. Following FVSS, none of the 15 patients experienced infection, nerve injury, shunt loss, or obstruction. 13 patients improved dramatically after surgery, while 2 patients improved significantly in the early postoperative period, but the primary symptoms returned 2 months later. The Japanese Orthopedic Association (JOA) score was $12.67\pm 3.95$ , which was considerably better than preoperatively ( $t=3.69$ , $P$ 0.001). The MRI results revealed that the cavities in 13 patients were reduced by at least 50% compared to the cavities measured preoperatively. The shrinkage rate of syringomyelia was 86.67% (13/15). One patient’s cavities nearly vanished following syringomyelia. The size of the cavity in the patient remain unchanged, and the cavity’s maximal diameter was significantly smaller than the size measured preoperatively ( $P<0.001$ ) PC-MRI results indicated that the peak flow rate of cerebrospinal fluid at the central segment of the midbrain aqueduct and the foramen magnum in patients during systole and diastole were significantly reduced after surgery ( $P<0.05$ ). Conclusion. After posterior fossa decompression, FVSS can effectively restore the smooth circulation of cerebrospinal fluid and alleviate clinical symptoms in patients with recurrent Chiari (type I) malformation and syringomyelia. It is a highly effective way of treatment.

Diagnosis and treatment of Chiari malformation and syringomyelia in adults: international consensus document

BACKGROUND

Syringomyelia and Chiari malformation are classified as rare diseases on Orphanet, but international guidelines on diagnostic criteria and case definition are missing.

AIM OF THE STUDY

to reach a consensus among international experts on controversial issues in diagnosis and treatment of Chiari 1 malformation and syringomyelia in adults.

METHODS

A multidisciplinary panel of the Chiari and Syringomyelia Consortium (4 neurosurgeons, 2 neurologists, 1 neuroradiologist, 1 pediatric neurologist) appointed an international Jury of experts to elaborate a consensus document. After an evidence-based review and further discussions, 63 draft statements grouped in 4 domains (definition and classification/planning/surgery/isolated syringomyelia) were formulated. A Jury of 32 experts in the field of diagnosis and treatment of Chiari and syringomyelia and patient representatives were invited to take part in a three-round Delphi process. The Jury received a structured questionnaire containing the 63 statements, each to be voted on a 4-point Likert-type scale and commented. Statements with agreement <75% were revised and entered round 2. Round 3 was face-to-face, during the Chiari Consensus Conference (Milan, November 2019).

RESULTS

Thirty-one out of 32 Jury members (6 neurologists, 4 neuroradiologists, 19 neurosurgeons, and 2 patient association representatives) participated in the consensus. After round 2, a consensus was reached on 57/63 statements (90.5%). The six difficult statements were revised and voted in round 3, and the whole set of statements was further discussed and approved.

CONCLUSIONS

The consensus document consists of 63 statements which benefited from expert discussion and fine-tuning, serving clinicians and researchers following adults with Chiari and syringomyelia.

The Management of Idiopathic and Refractory Syringomyelia

Idiopathic syringomyelia (IS) and refractory syringomyelia (RS) are types of syringomyelia that often pose a management challenge and are associated with long-term clinical sequela. They are usually an epiphenomenon reflecting an underlying pathology where the treatment of the primary cause should be the aim for any surgical intervention. In the case of IS, the initial step is agreeing on the definition of the terms idiopathic and syringomyelia. After a rigorous exhaustive clinic-radiological workup, only IS patients with progressive neurology are treated, usually unblocking subarachnoid cerebrospinal fluid (CSF) pathway obstruction somewhere in the thoracic spinal canal and reserving shunting techniques to nonresponsive cases. Similar to IS, also RS is multifactorial, and its management varies based on the initial pathology, strongly supported by radiological and clinical features. We aim to address this topic focusing on the etiopathology, investigation paradigm, and surgical pathway, formulating algorithms of management with available evidence in literature. Surgical techniques are discussed in detail.

Leptomeningeal pneumocephalus and pneumorrhachis: Signs of pneumothorax in case of syringopleural shunting

In this article, we present a case of leptomeningeal pneumocephalus and pneumorrhachis secondary to pneumothorax that occurred six years after syringopleural shunting.

Syrinx shunts for syringomyelia: a systematic review and meta-analysis of syringosubarachnoid, syringoperitoneal, and syringopleural shunting

OBJECTIVE

Syringomyelia is a debilitating, progressive disease process that can lead to loss of neurological function in patients already experiencing significant compromise. Syringosubarachnoid, syringoperitoneal, and syringopleural shunts are accepted treatment options for patients with persistent syringomyelia, but direct comparisons have been lacking to date. The authors conducted a systematic review of the literature and meta-analysis to compare clinical outcomes between these three syrinx shunt modalities.

METHODS

Utilizing PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for systematic reviews, Ovid Embase, PubMed, Scopus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, American College of Physicians Journal Club, and Database of Abstracts of Review of Effectiveness were searched to identify all potentially relevant studies published from inception until July 2020. Data were extracted and analyzed using meta-analysis of proportions. The primary study outcome was the rate of reoperation based on the initial shunt modality. Secondary outcomes included clinical improvement, clinical deterioration, and complications following shunt placement.

RESULTS

A total of 22 articles describing 27 distinct treatment cohorts published between 1984 and 2019 satisfied the inclusion criteria. This captured 473 syrinx shunt procedures, 193 (41%) by syringosubarachnoid shunt, 153 (32%) by syringoperitoneal shunt, and 127 (27%) by syringopleural shunt, with an overall median clinical follow-up of 44 months. The pooled incidences of revision surgery were estimated as 13% for syringosubarachnoid, 28% for syringoperitoneal, and 10% for syringopleural shunts, respectively (p-interaction = 0.27). The rate of clinical improvement was estimated as 61% for syringosubarachnoid, 64% for syringoperitoneal, and 71% for syringopleural shunts. The rate of clinical deterioration following placement was estimated as 13% for syringosubarachnoid, 13% for syringoperitoneal, and 10% for syringopleural shunts.

CONCLUSIONS

The preferred modality of syrinx shunting remains a controversial topic for symptomatic syringomyelia. This study suggests that while all three modalities offer similar rates of clinical improvement and deterioration after placement, syringoperitoneal shunts have a greater rate of malfunction requiring surgical revision. These data also suggest that syringopleural shunts may offer the best rate of clinical improvement with the lowest rate of reoperation.

Recurrent symptomatic pleural effusion from a syringopleural shunt

A patient with a syringopleural shunt with dyspnea and cough was found to have a recurrent large pleural effusion. Computed tomography of the thorax revealed the syringopleural shunt catheter abutting the pleural effusion, and beta-2 transferrin was detected in the pleural fluid, suggesting that the recurrent symptomatic pleural effusion was secondary to the syringopleural shunt. Physicians should be cognizant of this potential long-term complication of syringopleural shunts. Management includes revising the shunt with a programmable device or converting it to a syringoperitoneal or syringoarachnoid shunt.

Development of pre-syrinx state and syringomyelia following a minor injury: a case report

Background

A generally accepted rule is that posttraumatic syringomyelia (PTS) results from spinal cord injury (SCI).

Case presentation

Here, we report the development of syringomyelia without SCI in a 54-year-old Caucasian man following a mild motor vehicle accident. The computed tomography on admission excluded an injury of the spine. Because of neck and back pain, magnetic resonance imaging was performed on day 3 post-injury and demonstrated minimal changes from a ligamentous strain at the cervicothoracic transition. Any traumatic affection of the bone, vertebral discs, intraspinal compartment, or spinal cord were excluded. Some limb weakness and neurogenic bladder dysfunction started manifesting within the following weeks. Repeated MRIs following the accident demonstrated arachnoid adhesions at the C1–2 level and spinal cord edema equivalent to a pre-syrinx state at 12 months and syrinx formation at 24 months. Because of further deterioration, decompression was performed at 36 months.

Conclusions

We conclude that even after a minor trauma PTS can occur and that medullary edema (pre-syrinx state) may precede syrinx formation.

Treatment of posttraumatic syringomyelia: evidence from a systematic review

Background

Following spinal cord injury (SCI), the routine use of magnetic resonance imaging (MRI) resulted in an incremental diagnosis of posttraumatic syringomyelia (PTS). However, facing four decades of preferred surgical treatment of PTS, no clear consensus on the recommended treatment exists. We review the literature on PTS regarding therapeutic strategies, outcomes, and complications.

Methods

We performed a systematic bibliographic search on (“spinal cord injuries” [Mesh] AND “syringomyelia” [Mesh]). English language literature published between 1980 and 2020 was gathered, and case reports and articles examining syrinx due to other causes were excluded. The type of study, interval injury to symptoms, severity and level of injury, therapeutic procedure, duration of follow-up, complications, and outcome were recorded.

Results

Forty-three observational studies including 1803 individuals met the eligibility criteria. The time interval from SCI to the diagnosis of PTS varied between 42 and 264 months. Eighty-nine percent of patients were treated surgically (n = 1605) with a complication rate of 26%. Symptoms improved in 43% of patients postoperatively and in 2% treated conservatively. Stable disease was documented in 50% of patients postoperatively and in 88% treated conservatively. The percentage of deterioration was similar (surgery 16%, 0.8% dead; conservative 10%). Detailed analysis of surgical outcome with regard to symptoms revealed that pain, motor, and sensory function could be improved in 43 to 55% of patients while motor function deteriorated in around 25%. The preferred methods of surgery were arachnoid lysis (48%) and syrinx drainage (31%).

Conclusion

Even diagnosing PTS early in its evolution with MRI, to date, no satisfactory standard treatment exists, and the present literature review shows similar outcomes, regardless of the treatment modality. Therefore, PTS remains a neurosurgical challenge. Additional research is required using appropriate study designs for improving treatment options.

Syringomyelia and hydromyelia: Current understanding and neurosurgical management

Syringomyelia is a rare disorder in which a fluid-filled cyst forms within the spinal cord, resulting in myelopathy. Meanwhile, the abnormal dilatation of the central canal is referred to as hydromyelia or slit-like syrinx. The most prevailing classification is based on anatomical features and pathogeny rather than pathophysiological mechanisms. It is usual to distinguish foraminal syringomyelia related mainly to abnormalities at the craniocervical junction, non-foraminal syringomyelia dealing with any cause of arachnoiditis (infection, inflammation, trauma…) and more rarely syringomyelia associated with intramedullary tumors. Although many pathophysiological theories have been argued over time, the prevailing one is that disturbances in cerebrospinal fluid (CSF) flow in the sub-arachnoid spaces disrupt flow velocity leading to the syrinx. Symptoms of paralysis, sensory loss and chronic pain commonly develop during the third/fourth decades of life. The natural history of syringomyelia is typically one of gradual, stepwise neurological deterioration extending over many years. Diagnosis is based on magnetic resonance imaging (MRI) including excellent morphological sequences (T1-, T2-, FLAIR-, T2*-, enhanced T1-) and dynamic MRI with careful study of CSF velocity (CISS, cine-MR sequences). Surgical management is at first dedicated to treat the cause of the syringomyelia, mainly to re-establish a physiological CSF pathway in the subarachnoid spaces. Mostly, the surgical goal is to enlarge the craniocervical junction with duraplasty. Other surgical strategies such as arachnoidolysis or shunt procedures are performed based on the pathogenic mechanisms or as second-line treatment. Medical treatments are also necessary as chronic pain is the main long-lasting symptom. As evolutive syringomyelia is a severe disease with a high impact on quality of life, it is recommended to treat without delay. There is no evidence for surgery for incidental asymptomatic syringomyelia or hydromyelia. Finally, syringomyelia associated with intramedullary tumors resolves spontaneously after tumor resection. Syringomyelia is a rare disease, which requires a dedicated multidisciplinary approach, emphasizing the need for a nationwide scientific organization so as to offer optimal care to the patient.

Direct syrinx drainage in patients with Chiari I malformation

While FMD is, to date, the primary treatment of symptomatic CM I, the treatment of Chiari malformation type I (CM I) associated syrinx remains controversial. In cases of persistent, progressive, or recurrent syrinx following FMD, direct syrinx drainage (DSD) is described as a safe and efficient option, leading to a good clinical and radiological outcome. However, studies at hand mostly include very heterogeneous patient populations, small cohorts, and are of retrospective nature. We provide an overview of the possible indications and outcome for DSD in CM I-associated syrinx. We discuss the different surgical techniques of DSD and review the available literature comparing different DSD techniques. Finally, we discuss the possible complications that might occur after DSD and how they can be prevented.

Safety and Efficacy of Syringoperitoneal Shunting with a Programmable Shunt Valve for Syringomyelia Associated with Extensive Spinal Adhesive Arachnoiditis: Technical Note

OBJECTIVE

Although syringomyelia associated with extensive spinal adhesive arachnoiditis (SAA) can be a progressive disease that has potentially devastating clinical consequences, its surgical resolution has remained poorly defined. The aim of the present study was to verify the safety and efficacy of syringoperitoneal shunting for syringomyelia associated with extensive SAA.

METHODS

The present retrospective study included 15 patients who had undergone syringoperitoneal shunting with a programmable shunt valve for the diagnosis of syringomyelia associated with extensive SAA from October 2012 to June 2018. The shunt pressure was appropriately adjusted according to the postoperative sequential clinical condition and change in syringomyelia evaluated using magnetic resonance imaging. The average postoperative follow-up duration was 32.7 months.

RESULTS

No surgery-related complications such as shunt dysfunction or infection occurred during the follow-up period, except for 2 patients with minor issues with the shunt tube. The average shunt pressure at the last follow-up examination was 4.5 cm H₂O. The findings from the clinical assessment suggested that the average grade on the sensory pain scale was 2.9 before surgery and had improved significantly to 2.5 at the most recent follow-up examination. Radiological analysis suggested that improvement of syringomyelia was noted in 14 of the 15 patients (93.3%), with no cases of radiological aggravation. No recurrence of syringomyelia developed during the follow-up period in the present study.

CONCLUSION

Syringoperitoneal shunting with a programmable shunt valve was safe and effective for clinical control of syringomyelia associated with extensive SAA. Long-term follow-up is mandatory to monitor for shunt dysfunction and mechanical trouble.

Effect of extradural constriction on CSF flow in rat spinal cord

Background

Fluid homeostasis in the central nervous system (CNS) is essential for normal neurological function. Cerebrospinal fluid (CSF) in the subarachnoid space and interstitial fluid circulation in the CNS parenchyma clears metabolites and neurotransmitters and removes pathogens and excess proteins. A thorough understanding of the normal physiology is required in order to understand CNS fluid disorders, including post-traumatic syringomyelia. The aim of this project was to compare fluid transport, using quantitative imaging of tracers, in the spinal cord from animals with normal and obstructed spinal subarachnoid spaces.

Methods

A modified extradural constriction model was used to obstruct CSF flow in the subarachnoid space at the cervicothoracic junction (C7–T1) in Sprague–Dawley rats. Alexa-Fluor 647 Ovalbumin conjugate was injected into the cisterna magna at either 1 or 6 weeks post–surgery. Macroscopic and microscopic fluorescent imaging were performed in animals sacrificed at 10 or 20 min post–injection. Tracer fluorescence intensity was compared at cervical and thoracic spinal cord levels between control and constriction animals at each post-surgery and post-injection time point. The distribution of tracer around arterioles, venules and capillaries was also compared.

Results

Macroscopically, the fluorescence intensity of CSF tracer was significantly greater in spinal cords from animals with a constricted subarachnoid space compared to controls, except at 1 week post-surgery and 10 min post-injection. CSF tracer fluorescence intensity from microscopic images was significantly higher in the white matter of constriction animals 1 week post surgery and 10 min post-injection. At 6 weeks post–constriction surgery, fluorescence intensity in both gray and white matter was significantly increased in animals sacrificed 10 min post-injection. At 20 min post-injection this difference was significant only in the white matter and was less prominent. CSF tracer was found predominantly in the perivascular spaces of arterioles and venules, as well as the basement membrane of capillaries, highlighting the importance of perivascular pathways in the transport of fluid and solutes in the spinal cord.

Conclusions

The presence of a subarachnoid space obstruction may lead to an increase in fluid flow within the spinal cord tissue, presenting as increased flow in the perivascular spaces of arterioles and venules, and the basement membranes of capillaries. Increased fluid retention in the spinal cord in the presence of an obstructed subarachnoid space may be a critical step in the development of post-traumatic syringomyelia.

Electronic supplementary material

The online version of this article (10.1186/s12987-019-0127-8) contains supplementary material, which is available to authorized users.

Tetraplegia associated with post-operative syringomyelia in spinal tuberculosis: a result of an epidural compartment syndrome?

Introduction

The commonly recognized causes of post-operative neurological deterioration in spinal tuberculosis are inadequate decompression, damage to vascular supply of the spinal cord, and multi-drug resistant organisms. There are no known cases of syringomyelia developing after surgical decompression of spinal tuberculosis.

Case presentation

A teenage girl presented with rapid onset quadriparesis secondary to a tubercular epidural abscess extending from C4-T8. The neurological status deteriorated to quadriplegia immediately following decompression by hemilaminectomy at C7 and T7 levels. Investigations into the cause of neurological deterioration revealed syrinx formation at T5-9 levels. The patient had partial motor and sensory recovery in the first 3 weeks post-operatively. Tubercular infection was treated with a 1-year course of multi-drug anti-tubercular therapy. However, there was no further neurological improvement at 2 years follow-up.

Discussion

Syringomyelia in tuberculosis has been associated with tubercular meningitis, intradural tuberculomas, and post-surgical vascular insult. None of these were implicated as the cause of syrinx formation in this case. We hypothesize that the rapid evolution of epidural abscess in an intact vertebral column led to an acute "epidural compartment syndrome", which caused ischemic damage to the spinal cord. Compression caused by the epidural abscess was relieved by surgical decompression, allowing the central canal to dilate and expand into the softened spinal parenchyma, hence leading to syrinx formation.

A simple technique for thoracoscopic assisted placement of the distal limb of syringopleural shunts

Background

Syringomyelia is an unusual accumulation of fluid within the spinal cord that may be associated with significant neurologic symptoms. Surgical drainage using various techniques is often required to reduce the intraparenchymal pressure and to alleviate symptoms. Syringopleural shunting seems to produce best results.

Patients and methods

A simple technique to insert the distal limb of the syringopleural shunt into the pleural space is described in detail. The patient is placed in prone position. The syrinx is accessed from a dorsal incision and the proximal limb is inserted into the fluid cavity. The tube is tunneled through the subcutaneous space laterally and caudally. A 5mm blunt port is inserted lateral to the scapula and advanced under visual control using a 5mm 30° camera through the subcutaneous tissue and muscle and at the upper border of the 5th rib through the intercostals. With ventilation paused, the pleura is penetrated and CO2 is insufflated with a pressure of 8mm mercury. Under visual control the distal limb of the shunt is inserted at the pleural recessus and the tube is directed cranially. Positive airway pressure is applied re-expanding the lung. The trocar is removed from the pleural cavity and the skin is closed with subcuticular sutures.

Results

The shunt was successfully placed in three consecutive cases including one redo case (1 male, 1 female aged 50 and 51 years with post traumatic syrinx). Postoperative chest x-ray excluded pneumothorax and no chest tube was required. Neurologic improvement was achieved in both patients.

Conclusions

General surgeons should be familiar with this simple technique similar to laparoscopic assisted placement of distal ventriculoperitoneal shunt catheters into the abdominal cavity.

Cystic Dilation of the Ventriculus Terminalis: Report of 6 Surgical Cases Treated with Cyst-Subarachnoid Shunting Using a T-Catheter

BACKGROUND

Cystic dilation of the ventriculus terminalis (CDVT) is a rare anatomic variation that and may become symptomatic. Literature regarding CDVT is limited, and thus the clinical characteristics and management strategy of CDVT are unclear. Here we report 6 cases of CDVT seen in our institution, and provide a review of the current literature.

METHODS

The study cohort comprised 6 patients with CDVT seen at Beijing Tiantan Hospital between September 2010 and June 2015. All 6 patients were managed surgically. Data on age, sex, clinical presentation, radiologic features, operative methods, and surgical outcomes were reviewed retrospectively. We evaluated the clinical outcomes and postoperative radiologic changes of these patients and compared them with findings of similar previous reports.

RESULTS

All 6 patients were female, with a median age of 50.0 years (interquartile range [IQR], 25.8-54.0 years). Surgical management of cyst-subarachnoid shunting using T-catheter after myelotomy was successfully performed in all patients. During an average follow-up of 41 months, relief of clinical symptoms, especially low-back pain and sciatica, were observed in all 6 patients. No patients experienced symptom recurrence during follow-up, and postoperative magnetic resonance imaging revealed no regrowth of the lesion. Patients with focal neurologic deficits and sphincter disorders also achieved symptom relief from the procedure.

CONCLUSIONS

CDVT is an extremely rare cause of conus medullaris syndrome with an unclear treatment strategy. Our successful surgical management of 6 cases through cystic-subarachnoid shunting using a T-catheter for CDVT drainage provides a potential option for treating CDVT.

Surgical Management of Syringomyelia Associated with Spinal Adhesive Arachnoiditis, a Late Complication of Tuberculous Meningitis: A Case Report

Syringomyelia associated with tuberculous meningitis is an extremely rare condition. Only a few studies have reported clinical experience with syringomyelia as a late complication of tuberculous meningitis. Twenty-six years after a tuberculous meningitis episode, a 44-year-old man presented with progressively worsening spastic paresis of the lower limbs and impaired urinary function for 2 years. Radiological examination revealed syringomyelia extending from the level of C2 to T9 and arachnoiditis with atrophy of the spinal cord between C2 and T3. We performed laminectomy from C7 to T1, dissected the arachnoid adhesion and placed a syringo-pleural shunt via keyhole myelotomy. One year after the operation, his neurological condition improved. The postoperative control magnetic resonance imaging revealed the correctly located shunt and significantly diminished syringomyelia cavities. We aim to discuss the mechanism of syrinx formation following tuberculous meningitis and to share our surgical therapeutic experience with this rare disease entity.

Treatment of Posttubercular Syringomyelia Not Responsive to Antitubercular Therapy: Case Report and Review of Literature

Posttubercular adhesive arachnoiditis is a rare, late complication of tubercular meningitis. Syringomyelia can develop as a consequence of intramedullary cystic lesions and cerebrospinal fluid (CSF) flow disturbance around the spinal cord, even after successful chemotherapy. We reviewed the literature related to posttubercular syringomyelia treatment and suggest a new combined surgical approach. A 25-year-old Nigerian male patient presented with legs numbness, urinary disturbance, and legs weakness. Spinal magnetic resonance revealed a T5-T7 syringomyelia, secondary to adhesive spinal arachnoiditis related to a history of tuberculous meningitis. Adhesiolysis by direct visualization with a flexible endoscope was performed and a handmade S-italic syringe-subdural shunt was placed to restore CSF flow. During the postoperative course, the neurological deficits improved together with the resolution of the syrinx. Long-term magnetic resonance imaging follow-up documented no recurrences or shunt displacements. We suggest that, when antitubercular therapy is not effective to resolve postarachnoiditis syrinx, arachnolysis with a flexible endoscope together with the placement of an S-italic shunt allowed free CSF communication between the syrinx and the subarachnoid space. Furthermore, we support that the use of an s-shaped shunt could prevent displacement or migration of the device and allows an easier revision in case of acute or late complications.

Update on the pathophysiology and management of syringomyelia unrelated to Chiari malformation

INTRODUCTION

Much has been published on syringomyelia related to Chiari malformation. In contrast, little is known about the condition when it is not associated with this malformation, but this presentation of syringomyelia constitutes a different entity and therefore requires specific management. We conducted a literature review to summarise the most accepted and widespread ideas about the pathophysiology, management and other aspects of syringomyelia unrelated to Chiari malformation.

DEVELOPMENT

We reviewed the most relevant literature on this condition, focusing on the pathophysiology, clinical presentation, diagnosis, and treatment.

CONCLUSIONS

Syringomyelia unrelated to Chiari malformation is a distinct entity that must be well understood to guarantee correct diagnosis, monitoring, and management. When the disease is suspected, a thorough study should be conducted to identify its aetiology. Treatment must aim to eliminate the cause of the disease; symptomatic treatment should remain a second-line option.

Intracranial hypotension after syringopleural shunting in posttraumatic syringomyelia: Case report and review of the literature

We report a case of a 45-year-old male with a syringopleural shunt who developed intracranial hypotension. The patient presented with 2 weeks history of worsening headache and back pain, on a background of having had a syringopleural shunt inserted for a thoracic posttraumatic syrinx. Computerized tomography imaging of the brain revealed bilateral subdural fluid collections. Magnetic resonance imaging appearances of spinal and intracranial pachymeningeal enhancement confirmed intracranial hypotension. We present a rare case of intracranial hypotension secondary to syringopleural shunting in a patient with posttraumatic syringomyelia.

Arachnolysis or cerebrospinal fluid diversion for adult-onset syringomyelia? A Systematic review of the literature

OBJECTIVE

To identify surgical practice patterns in the literature for nonpediatric syringomyelia by systematic review and to determine the following: 1) What is the best clinical practice of cerebrospinal fluid (CSF) diversion to maximize clinical improvement or to achieve the lowest recurrence rate? 2) Does arachnolysis, rather than CSF diversion, lead to prolonged times to clinical recurrence?

METHODS

A database search comprising PubMed, Cochrane Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Scopus, and Cochrane Database of Systematic Reviews was conducted to find pertinent articles on postinfectious, posttraumatic, or idiopathic syringomyelia.

RESULTS

An advanced PubMed search in August 2012 yielded 1350 studies, including 12 studies meeting Oxford Centre for Evidence-Based Medicine criteria for level IV evidence as a case series, with a total of 410 patients (mean age, 39 years). Data on 486 surgeries were collected. Mean follow-up data were available for 10 studies, with a mean follow-up time of 62 months. On regression analysis, increased age had a significant correlation with a higher likelihood of having clinically significant recurrence on mean follow-up (P < 0.05). The use of arachnolysis in surgery was associated with a longer duration until clinically symptomatic recurrence (P = 0.02). Data on mortality were unavailable. The mean number of surgeries per patient across all studies was 1.20 (range, 0.95-2.00).

CONCLUSIONS

With postinfectious and posttraumatic etiologies, arachnolysis was the only surgical treatment to have a statistically significant effect on decreasing recurrence rates. More prospective, randomized, controlled studies are required to reach a clear consensus.

Worsening or development of syringomyelia following Chiari I decompression: case report

OBJECT

The effects of posterior fossa decompression on Chiari malformation Type I-induced syringomyelia have been well described. However, treatment of worsening syringomyelia after Chiari decompression remains enigmatic. This paper defines patient and clinical characteristics as well as treatment and postoperative radiological and clinical outcomes in patients experiencing this complication.

METHODS

The authors performed a retrospective review of patients at the Children's Hospital of Pittsburgh and Children's of Alabama who developed worsening syringomyelia after Chiari decompression was performed.

RESULTS

Fourteen children (age range 8 months to 15 years), 7 of whom had preoperative syringomyelia, underwent posterior fossa decompression. Aseptic meningitis (n = 3) and bacterial meningitis (n = 2) complicated 5 cases (4 of these patients were originally treated at outside hospitals). Worsening syringomyelia presented a median of 1.4 years (range 0.2-10.3 years) after the primary decompression. Ten children presented with new, recurrent, or persistent symptoms, and 4 were asymptomatic. Secondary Chiari decompression was performed in 11 of the 14 children. The other 3 children were advised to undergo secondary decompression. A structural cause for each failed primary Chiari decompression (for example, extensive scarring, suture in the obex, arachnoid web, residual posterior arch of C-1, and no duraplasty) was identified at the secondary operation. After secondary decompression, 8 patients' symptoms completely resolved, 1 patient's condition stabilized, and 2 patients remained asymptomatic. Radiologically, 10 of the 11 children had a decrease in the size of their syringes, and 1 child experienced no change (but improved clinically). The median follow-up from initial Chiari decompression was 3.1 years (range 0.8-14.1 years) and from secondary decompression, 1.3 years (range 0.3-4.5 years). No patient underwent syringopleural shunting or other nonposterior fossa treatment for syringomyelia.

CONCLUSIONS

Based on the authors' experience, children with worsening syringomyelia after decompression for Chiari malformation Type I generally have a surgically remediable structural etiology, and secondary exploration and decompression should be considered.

Long-term results and complications of the syringopleural shunting for treatment of syringomyelia: a clinical study

BACKGROUND

The use of drains in the treatment of syringomyelia has a simple and immediate appeal. Syringopleural shunting in syringomyelia has produced good short-term results, but limited information is available on long-term effects. We analyzed the complications and long-term outcomes after syringopleural shunting for syringomyelia.

CLINICAL MATERIAL AND METHODS

Fourthy-four patients with large-sized syringomyelia underwent syringopleural shunting because of spinal cord compression between 1992 and 2010 in our clinic. Thirty-two patients had Chiari malformation type I (Group B), and 12 patients were associated with primary parenchymal cavitations (Group A). Their ages ranged from 14 to 71 years. Both craniovertebral decompression and syringopleural shunting were performed on 21 patients, whereas only syringopleural shunting was performed on another 21 patients.

RESULTS

The follow-up period ranged from 1 year to 17 years (mean: 9.1 years). There was no operative mortality. Early postoperative MRI revealed that syringes of 43 patients had collapsed. There were 9 (20.5%) minor complications in 9 patients, including temporary neurological deficits (6), respiratory distress (2) and headache (1). Seven (15.9%) serious complications [permanent neurological deficit (1), shunt migration (2), shunt misplacement (1), spinal instability (1), tethering (1), CSF over drainage (1)] were seen in five patients. Four of them were treated with a secondary operation. Three patients (3/9; 33.3%) who were treated by syringopleural shunt alone (Group B2) required craniovertebral decompression, although the shunt was functional. During long-term follow-up, three patients stabilized, five patients (11.3%) developed a worse neurological condition, and two of these patients died 10 and 7 years after surgery. Of all patients, 88.6% showed significant clinical improvement.

CONCLUSIONS

Although there were complications and failures, syringopleural shunting produced satisfactory results at long-term follow-up.

Spinal syringomyelia following subarachnoid hemorrhage

Subarachnoid blood has been reported as a cause of chronic spinal arachnoiditis. Although syringomyelia has been thought to be caused by spinal arachnoiditis, reports of syringomyelia following aneurysmal subarachnoid hemorrhage (SAH) are very rare. We describe two patients with syringomyelia associated with chronic spinal arachnoiditis following SAH. From January 2001 to December 2010, 198 patients with aneurysmal SAH were treated at Kinki University School of Medicine. Two of the 198 patients had syringomyelia following aneurysmal SAH; thus the rate of syringomyelia associated with aneurysmal SAH was 1.0%. Patient 1 was a 54-year-old woman who presented with back pain, back numbness and gait disturbance 20 months after SAH. Her MRI revealed syringomyelia of the spinal cord from C2 to T10. She underwent shunting of the syrinx to the subarachnoid space. Patient 2 was a 49-year-old man, who was admitted to the hospital with headache, diplopia, hoarseness, dysphagia and ataxia five months after SAH. MRI revealed syringomyelia from the medulla oblongata to C6, and an enlargement of the lateral and fourth ventricles. After foramen magnum decompression and C1 laminectomy, a fourth ventricle-subarachnoid shunt was placed by insertion of a catheter. Spinal arachnoiditis and spinal syringomyelia are rare but important chronic complications after SAH.

Pathophysiology of persistent syringomyelia after decompressive craniocervical surgery. Clinical article

OBJECT

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.