Spinal cord vascular shunts: spinal cord vascular malformations and dural arteriovenous fistulas

The hybrid operation based on microsurgery assisted by intraoperative spinal angiography in patients with spinal dural arteriovenous fistula: a series of 45 cases from multicenter research

BACKGROUND

To assess the clinical effects of hybrid surgery, which includes spinal angiography-assisted microsurgery, in the treatment of spinal dural arteriovenous fistulas (SDAVF).

METHODS

We retrospectively reviewed 45 patients who underwent hybrid Spinal dural arteriovenous fistula (SDAVF) resection between September 2019 and June 2022. The hybrid surgery involved intraoperative digital subtraction angiography (DSA) of the spinal vessels to determine the source of the blood-supplying artery, location of the fistula and draining vein, indocyanine green fluorescence (ICG)-assisted microsurgical resection of the fistula, and postoperative DSA to verify therapeutic efficacy. The Hamilton Anxiety Scale (HAMA), Hamilton Depression Scale (HAMD), Visual Analog Scale (VAS), Barthel score, modified Rankin Scale (mRS) and modified Aminoff-Logue score (key indicator) were used to assess the clinical effects of SDAVF resection.

RESULTS

A series of 45 patients with SDAVF were successfully treated with hybrid surgery without fistula recurrence. There were no intraoperative complications related to spinal angiography, and none of the patients died. Postoperatively, two patients experienced clinical deterioration of spinal cord function, which manifested as bilateral lower extremity paralysis and bladder sphincter dysfunction. Postoperatively, improvement in mALS scores was observed in 16 cases (35.6%) within 1-2 days, 12 cases (26.7%) at 1 week, and 7 cases (15.6%) at 6 months. No SDAVF recurrence was detected in the spinal MRA examination 6 months after surgery. When compared with preoperative mALS scores, 35 cases (77.8%) showed significant improvement in symptoms, 8 cases (17.8%), remained unchanged, and 2 cases (4.4%) deteriorated. Compared with the preoperative scores, the postoperative mALS score was significantly decreased [postoperative vs. preoperative: 2(1,3) vs. 3(2,4)], HAMD score [(12.2 ± 5.5) vs. (19.6 ± 6.3)], HAMA score [(15.6 ± 5.5) vs. (20.5 ± 6.5)], and VAS score [3(2,5) vs. 5(4,8)]. Conversely, Barthel scoresshowed significant increase [(74.6 ± 8.7) vs. (67.8 ± 9.2)] (P < 0.05). However, the mRS scores were lower than preoperatively [1(1,2) vs. 2(1,2.5)], but the difference was not statistically significant (P > 0.05). There was a significant increase in "good" neurological outcomes at follow-up compared with preoperative function (62.2% vs. 33.3%) (P = 0.023).

CONCLUSION

Hybrid surgery is a safe and effective treatment for patients with SAVF, which is beneficial for improving anxiety, depression, spinal cord, and neurological function, and relieving pain. However, the treatment of patients with SDAVF is a complex, long-term process requiring further multidisciplinary interventions, including clinical care, psychosocial interventions, and neurorehabilitation.

Surgery versus endovascular treatment for spinal dural arteriovenous fistulas: a multicenter experience and systematic literature review

Surgery and endovascular therapy are the primary treatment options for spinal dural arteriovenous fistula (SDAVF). Due to the absence of a consensus regarding which therapy yields a superior outcome, we conducted a comparative analysis of the surgical and endovascular treatment of SDAVF through a multicenter case series and a systematic literature review. Patients with SDAVF, surgically or endovascularly treated at four neurosurgical centers from January 2001 to December 2021, were included in this study. Level of SDAVF, primary treatment modality, baseline and post-procedural neurological status were collected. The primary outcomes were failure, complication rates, and a newly introduced parameter named as therapeutic delay. A systematic review of the literature was performed according to PRISMA-P guidelines. The systematic review identified 511 papers, of which 18 were eligible for analysis, for a total of 814 patients, predominantly male (72%) with a median age of 61 and mainly thoracic SDAVFs (65%). The failure rate was significantly higher for endovascular therapy (20%) compared to surgery (4%) (p < 0.01). Neurological complications were generally rare, with similar rates among the two groups (endovascular 2.9%; surgery 2.6%). Endovascular treatment showed a statistically significantly higher rate of persistent neurological complications than surgical treatment (2.9% versus 0.2%; p < 0.01). Both treatments showed similar rates of clinical improvement based on Aminoff Logue scale score. The multicenter, retrospective study involved 131 patients. The thoracic region was the most frequent location (58%), followed by lumbar (37%). Paraparesis (45%) and back pain (41%) were the most common presenting symptoms, followed by bladder dysfunction (34%) and sensory disturbances (21%). The mean clinical follow-up was 21 months, with all patients followed for at least 12 months. No statistically significant differences were found in demographic and clinical data, lesion characteristics, or outcomes between the two treatment groups. Median pre-treatment Aminoff-Logue score was 2.6, decreasing to 1.4 post-treatment with both treatments. The mean therapeutic delay for surgery and endovascular treatment showed no statistically significant difference. Surgical treatment demonstrated significantly lower failure rates (5% vs. 46%, p < 0.01). In the surgical group, 2 transient neurological (1 epidural hematoma, 1 CSF leak) and 3 non-neurological (3 wound infections) complications were recorded; while 2 permanent neurological (spinal infarcts), and 5 non-neurological (inguinal hematomas) were reported in the endovascular group. According to the literature review and this multicenter clinical series, surgical treatment has a significantly lower failure rate than endovascular treatment. Although the two treatments have similar complication rates, endovascular treatment seems to have a higher rate of persistent neurological complications.

Extravertebral low back pain: a scoping review

BACKGROUND

Low back pain (LBP) is one of the most common reasons for consultation in general practice. Currently, LBP is categorised into specific and non-specific causes. However, extravertebral causes, such as abdominal aortic aneurysm or pancreatitis, are not being considered.

METHODS

A systematic literature search was performed across MEDLINE, Embase, and the Cochrane library, complemented by a handsearch. Studies conducted between 1 January 2001 and 31 December 2020, where LBP was the main symptom, were included.

RESULTS

The literature search identified 6040 studies, from which duplicates were removed, leaving 4105 studies for title and abstract screening. Subsequently, 265 publications were selected for inclusion, with an additional 197 publications identified through the handsearch. The majority of the studies were case reports and case series, predominantly originating from specialised care settings. A clear distinction between vertebral or rare causes of LBP was not always possible. A range of diseases were identified as potential extravertebral causes of LBP, encompassing gynaecological, urological, vascular, systemic, and gastrointestinal diseases. Notably, guidelines exhibited inconsistencies in addressing extravertebral causes.

DISCUSSION

Prior to this review, there has been no systematic investigation into extravertebral causes of LBP. Although these causes are rare, the absence of robust and reliable epidemiological data hinders a comprehensive understanding, as well as the lack of standardised protocols, which contributes to a lack of accurate description of indicative symptoms. While there are certain disease-specific characteristics, such as non-mechanical or cyclical LBP, and atypical accompanying symptoms like fever, abdominal pain, or leg swelling, that may suggest extravertebral causes, it is important to recognise that these features are not universally present in every patient.

CONCLUSION

The differential diagnosis of extravertebral LBP is extensive with relatively low prevalence rates dependent on the clinical setting. Clinicians should maintain a high index of suspicion for extravertebral aetiologies, especially in patients presenting with atypical accompanying symptoms.

Knowledge, attitudes and practices regarding spinal vascular malformations among doctors in China: a cross-sectional study

OBJECTIVE

Knowledge, attitude and practice (KAP) models are essential tools for assessing healthcare professionals' understanding, beliefs and behaviours towards specific health issues. This study aimed to explore the KAP of Chinese doctors in diagnosing and treating spinal vascular malformations (SVM).

DESIGN

A web-based cross-sectional survey.

SETTING

This study was conducted between October and December 2022 through a self-administered questionnaire.

PARTICIPANTS

Participants include full-time doctors who voluntarily participate. Doctors in advanced training, regular training or internships were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

The KAP scores of Chinese doctors in diagnosing and treating SVM measured by the questionnaire.

RESULTS

A total of 517 doctors participated in the study, mostly in Shaanxi, China, working in SVM-relevant departments (n=396) or other departments (n=121). The doctors achieved an average knowledge score of 9.66±1.95 (range: 0-12), attitude score of 22.16±1.71 (range: 6-30) and practice scores of 46.13±5.35 for those in SVM-relevant departments (neurosurgery, orthopaedics and neurology) and 8.50±1.25 for those in other departments, respectively, revealing doctors have adequate knowledge, positive attitude and good practice, and those in SVM-relevant departments showing more adeptness compared with those in other departments. Moreover, multivariate logistic regression analysis showed that knowledge about SVM (OR=1.72, 95% CI 1.11 to 2.65, p=0.015), holding a master's degree (OR=1.85, 95% CI 1.14 to 3.00, p=0.013) and working in orthopaedics (OR=0.34, 95% CI 0.13 to 0.88, p=0.026) were independently associated with good attitude.

CONCLUSION

Chinese doctors showed adequate knowledge, moderate attitudes and good practice regarding SVM. A continuing education programme may improve clinical practitioners' ability to manage SVM.

Endovascular and surgical obliteration rates of spinal dural arteriovenous fistulae: a single UK Centre experience

OBJECTIVE

Endovascular treatment (EVT) of spinal dural arteriovenous fistulae (SDAVF) has become increasingly popular given its less invasive nature. This study aims to assess radiological obliteration rates after surgery and EVT for SDAVF in a major tertiary referral centre serving a population of 2.2 million.

METHOD

A retrospective review of all patients diagnosed with SDAVF between February 2010 and February 2018 was undertaken, identifying baseline demographics, treatment modality and the final radiological outcome (i.e., persistence of the SDAVF). Patients were identified from the departmental neurovascular database, clinical notes and imaging reports.

RESULTS

Twenty patients were identified with an angiographically confirmed SDAVF. Two (10%) were managed conservatively. Nine patients (45%) underwent EVT. Obliteration was achieved in one patient (11%) after a single procedure, while one patient required two sessions. Further surgery was required in five patients (56%) to achieve complete obliteration. Nine patients (45%) underwent surgical disconnection as first treatment. Obliteration was radiologically confirmed in eight patients (89%). No radiological (MRI or angiographic) follow-up data was available for two patients (one from each group) and these were excluded from analysis. In this study, the obliteration rate of SDAVF after surgery was superior compared to EVT (p <0.01).

CONCLUSION

Complete obliteration and recurrence rates after single treatment with EVT were inferior compared to surgical intervention. EVT may be better suited for specific presentations of SDAVF either in isolation or as an adjunct in multi-modality treatment. A national registry of outcomes may aid ongoing refinement of patient selection for EVT.

Surgical evolution in spinal dural arteriovenous fistula treatment-a 7 years monocentric experience

Accounting for 70% of all spinal vascular malformations, spinal dural arteriovenous fistulas (SDAVF) are the most common type of malformation. Interruption of the fistulous arterialized vein point is the goal of surgical treatment. The aim of the study was to compare open surgery (laminectomy) versus minimal invasive surgery (MIS) in SDAVF treatment. Between March 2013 and March 2020, we retrospectively collected 21 consecutive adult patients with SDAVF. Since March 2017, MIS has been routinely used for surgical treatment. Pre- and post-operative clinical evaluations used Aminoff-Logue score (ALS). Complication rate was noted. Post-operative occlusion of the malformation was confirmed by digital subtraction angiography (DSA) in all patients. MIS was compared to open surgery in terms of efficacy and complications with statistical evaluation. Standard laminectomy was performed in 12 patients and MIS technique in 9 patients. No difference was noted on pre-operative parameters. ALS and MRI signs of myelopathy were improved in all cases except for 1 patient in each group. All SDAVFs were excluded based on post-operative DSA. Significant differences were noted between the 2 groups in terms of perioperative blood loss (p<0.001), post-operative pain visual analog scale values (p<0.001), and first time out of bed (p<0.001). Wrong level surgery occurred in one patient in each group; patients were re-operated using the same technique. No infection or cerebrospinal fluid (CSF) leak was noted. In our experience, MIS is a safe alternative to open laminectomy for SDAVF treatment. MIS contributes to patient comfort and minimizes blood loss without increasing complication rate.

Spinal Vascular Malformations: Treatment and Outcome

BACKGROUND

Vascular malformations of the spinal cord are a rare and complex clinical entity and can lead to severe morbidity with progressive spinal cord symptoms if not treated properly. In early stages, the disease is characterized by slowly progressive, nonspecific symptoms, such as gait disturbance, paresthesia, diffuse sensory symptoms, and radicular pain; in the late stages, bowel and bladder incontinence, erectile dysfunction, and urinary retention may develop. In recent decades, understanding and treatment of spinal vascular malformations have improved with the evolution of diagnostic tools and treatment modalities; however, it is still difficult to manage these cases because of the complexity of the pathology. The aims of this study were to present the long-term outcomes of our patients and to discuss the optimal management strategies.

METHODS

We reviewed the records of 78 patients with spinal vascular malformations and performed a retrospective, single-center case series evaluating initial occlusion, recanalization, retreatment, and neurologic status of patients with dural arteriovenous fistulas, perimedullary arteriovenous fistulas, arteriovenous malformations, and extradural arteriovenous fistulas who had undergone embolization and/or surgery.

RESULTS

No mortality was observed. Complete obliteration was achieved in 76 patients (97.4%).

CONCLUSIONS

Both endovascular and surgical treatment of spinal vascular malformations resulted in significant long-term recovery from myelopathic symptoms and improvement in quality of life for most patients.

Spinal dural fistula and anterior spinal artery supply from the same segmental artery: Case report of volumetric T2 MRI diagnosis and rational endovascular treatment

Spinal dural fistulas (SDAVFs) occasionally arise from the same segmental artery as the radiculomedullary branch to the anterior spinal artery. In such cases, selective fistula embolization that does not endanger the anterior spinal artery is not possible, and surgical fistula disconnection is recommended. We present an exceptional case in which rational embolization strategy of SDAVF was feasible because of separate origins from a common segmental artery pedicle of the ventral radiculomedullary artery and the dorsal radicular artery branch supplying the fistula.

Spontaneous disappearance of a spinal dural arteriovenous fistula

We report a case of an unusual spontaneous obliteration of a spinal dural arteriovenous fistula after diagnosis confirmation through spinal angiography. To our knowledge, there are only two previously documented cases of spontaneous disappearance of non-traumatic spinal dural arteriovenous fistulas.

Temporal evolution of a patient with a spinal dural arteriovenous fistula on serial MRI

Introduction

A spinal dural arteriovenous fistula is a rare type of vascular malformation. If left untreated, these fistulas can result in significant neurological deficits secondary to spinal cord infarct or hemorrhage.

Case presentation

A 70-year-old female with a longstanding history of episodic progressive bilateral lower extremity weakness and sensory disturbances was previously misdiagnosed with multiple sclerosis. Imaging revealed a T2 signal change from T7 to the conus with associated signal change and she subsequently underwent a T10-L1 laminectomy for clip ligation of a spinal dural arteriovenous fistula. Here we present the clinical and radiographic progression of one patient with a spinal dural arteriovenous fistula.

Discussion

Spinal dural arteriovenous fistulas are a rare but treatable cause of myelopathy, so it is important to understand its natural progression and radiologic findings as it is frequently misdiagnosed.

Spinal arteriovenous fistulae: surgical management

Spinal vascular malformations include several types of pathologic entities with multiple variations in their neurologic presentation and risks. Spinal dural arteriovenous fistulae (SDAVF) are the most frequent type, and account for 70% of all lesions affecting the spinal cord. The nonspecific early neurologic symptoms of SDAVF often make early diagnosis of this clinical entity challenging, and a delay in diagnosis or appropriate treatment often has devastating consequences on spinal cord function. The lesion can invariably be obliterated with surgical occlusion of the intradural arterialized venous reflux, and progression of neurologic deficits is usually arrested and sometimes reversed.

Vascular Diseases of the Spinal Cord: Infarction, Hemorrhage, and Venous Congestive Myelopathy

Vascular pathologies of the spinal cord are rare and often overlooked. This article presents clinical and imaging approaches to the diagnosis and management of spinal vascular conditions most commonly encountered in clinical practice. Ischemia, infarction, hemorrhage, aneurysms, and vascular malformations of the spine and spinal cord are discussed. Pathophysiologic mechanisms, clinical classification schemes, clinical presentations, imaging findings, and treatment modalities are considered. Recent advances in genetic and syndromic vascular pathologies of the spinal cord are also discussed. Clinically relevant spinal vascular anatomy is reviewed in detail.

Concomitant origin of the anterior or posterior spinal artery with the feeder of a spinal dural arteriovenous fistula (SDAVF)

Background/objective

The concomitant origin of the anterior spinal artery (ASA) or the posterior spinal artery (PSA) from the feeder of a spinal dural arteriovenous fistula (SDAVF) is rare and the exact incidence is not known. We present our experience with the management of SDAVFs in such cases.

Methods

In 63 patients with SDAVF between 1993 and 2015, the feeder origin of the SDAVF was evaluated to determine whether it was concomitant with the origin of the ASA or PSA. Embolization was attempted when the patient did not want open surgery and an endovascular approach was regarded as safe and possible. The outcome of the procedure was evaluated as complete, partial, or no obliteration. The clinical outcome was evaluated by Aminoff–Logue (ALS) gait and micturition scale scores.

Results

Nine patients (14%) had a concomitant origin of the ASA or PSA with the feeder. There were two cervical, five thoracic, and two lumbar level SDAVFs. A concomitant origin of the feeder was identified with the ASA (n=7) and PSA (n=2). Embolization was performed in four patients and open surgery was performed in five. Embolization resulted in complete obliteration in three patients and partial obliteration in one. Using the ALS gait and micturition scale, the final outcome improved in six while three cases remained in an unchanged condition over 2–148 months.

Conclusions

The concomitant origin of the ASA or PSA with the feeder occurs occasionally. Complete obliteration of the fistula can be achieved either by embolization or open surgery. Embolization can be carefully performed in selected patients who are in a poor condition and do not want to undergo open surgery.

Spinal arteriovenous shunts: accuracy of shunt detection, localization, and subtype discrimination using spinal magnetic resonance angiography and manual contrast injection using a syringe

OBJECT

The object of this study was to evaluate the accuracy of fast 3D contrast-enhanced spinal MR angiography (MRA) using a manual syringe contrast injection technique for detecting and evaluating spinal arteriovenous shunts (AVSs).

METHODS

This was a retrospective study of 15 patients and 20 spinal MRA and catheter angiography studies. The accuracy of using spinal MRA to detect spinal AVS, localize shunts, and discriminate the subtype and dominant arterial feeder of the AVS were studied.

RESULTS

There were 14 pretherapeutic and 6 posttherapeutic follow-up spinal MRA and catheter spinal angiography studies. The spinal AVS was demonstrated in 17 of 20 studies. Spinal MRA demonstrated 100% sensitivity for detecting spinal AVS with no false-negative results. A 97% accuracy rate for AVS subtype discrimination and shunt level localization was achieved using this study's diagnostic criteria. The detection of the dominant arterial feeder was limited to 9 of these 17 cases (53%).

CONCLUSIONS

The fast 3D contrast-enhanced MRA technique performed using manual syringe contrast injection can detect the presence of a spinal AVS, locate the shunt level, and discriminate AVS subtype in most cases, but is limited when detecting small arterial feeders.

Retrograde leptomeningeal venous approach for dural arteriovenous fistulas at foramen magnum

A 72-year-old man presented with sudden right homonymous hemianopsia. Work-up imaging revealed a left occipital haematoma and an arteriovenous fistula supplied by the meningeal branches to the clivus from the left vertebral artery (VA) with a rostral venous reflux into cortical veins. A microcatheter was advanced through brainstem veins into the venous collector. A compliant balloon was placed in the left VA facing the origin of feeders. The balloon was inflated to protect the vertebrobasilar circulation from embolic migration. Onyx was injected by the transvenous catheter. Control angiogram revealed exclusion of the lesion. Informed consent was obtained from the patient.

The use of magnetic resonance imaging in predicting the clinical outcome of spinal arteriovenous fistula

PURPOSE

Magnetic resonance imaging (MRI) has been used to screen and follow-up spinal dural arteriovenous fistulae (SDAVF). The purpose of this study was to evaluate the association between MRI findings and neurologic function in SDAVF. This study also investigated clinical features and treatment results of SDAVF.

MATERIALS AND METHODS

A total of 15 consecutive patients who underwent embolization or surgery for SDAVF were included. We treated seven (60%) patients with embolization and six (40%) with surgery. We analysed clinical features, MRI findings, treatment results, and neurologic function. Neurologic function was measured by the Aminoff-Logue disability scale (ALS).

RESULTS

Patients with longer levels of intramedullary high signal intensity in preoperative T2-weighted images (T2WI) exhibited worse pre- and postoperative ALS scores (r=0.557, p=0.031; r=0.530, p=0.042, Pearson correlation). Preoperative ALS score was significantly correlated with postoperative ALS score (r=0.908, p=0.000, Pearson correlation). The number of levels showing intramedullary high signal intensity in T2WI decreased significantly postoperatively (5.2±3.1 vs. 1.0±1.4, p=0.001, Wilcoxon ranked test).

CONCLUSION

The number of involved levels of high signal intensity in preoperative T2WI is useful for predicting pre- and postoperative neurologic function in SDAVF.

Spinal glomus (type II) arteriovenous malformations: a pooled analysis of hemorrhage risk and results of intervention

BACKGROUND

The natural history and treatment results for spinal glomus (type II) arteriovenous malformations (AVMs) remain relatively obscure.

OBJECTIVE

To calculate spinal glomus (type II) AVM hemorrhages rates and amalgamate results of intervention.

METHODS

We performed a pooled analysis via the PubMed database through May 2012, including studies with at least 3 cases. Data on individual patients were extracted and analyzed using a Cox proportional hazards regression model to obtain hazard ratios for hemorrhage risk factors.

RESULTS

The annual hemorrhage rate before treatment was 4% (95% confidence interval [confidence interval]: 3%-6%), increasing to 10% (95% CI: 7%-16%) for AVMs with previous hemorrhage. The hazard ratio for hemorrhage after hemorrhagic presentation was 2.25 (95% CI: 0.71-7.07), increasing to 13.0 within the first 10 years (95% CI: 1.44-118). The overall rates of complete obliteration were 78% (95% CI: 72%-83%) for surgery and 33% (95% CI: 24%-43%) for endovascular treatment. Long-term clinical worsening occurred in 12% of patients after surgical treatment (95% CI: 8%-16%) and in 13% after endovascular treatment (95% CI: 7%-21%). No hemorrhages occurred after complete obliteration. After partial surgical treatment, the annual hemorrhage rate was 3% (95% CI: 1%-6%); no hemorrhages were reported over 196 patient-years after partial endovascular treatment.

CONCLUSION

Spinal glomus (type II) AVMs with previous hemorrhage, particularly within 10 years, demonstrated a greater risk of hemorrhage. Complete obliteration and even partial endovascular treatment significantly decreased their hemorrhage rate.

Spinal dural arteriovenous fistulas: clinical experience with endovascular treatment as a primary therapy at 2 academic referral centers

BACKGROUND AND PURPOSE

Spinal dural arteriovenous fistulas are a rare entity that, if left untreated, can lead to considerable morbidity with progressive spinal cord symptoms. The aim of this study was to evaluate the clinical outcome of patients with spinal dural arteriovenous fistulas that were primarily treated with endovascular embolization.

MATERIALS AND METHODS

A retrospective review was performed of all patients from 1997-2010 who underwent treatment at 2 academic referral centers for a spinal dural arteriovenous fistula. Follow-up was performed by clinical examination, and functional status was measured by use of the Aminoff-Logue Disability Scale, McCormick classification grading, and mRS scores. The nonparametric Wilcoxon signed rank test was used to compare pretreatment and posttreatment Aminoff-Logue Disability Scale gait and micturition scores, McCormick classification grading, and mRS scores. P values < .05 were considered significant.

RESULTS

A total of 38 patients were included. Five patients (2 endovascular, 3 surgical) were lost to follow-up and therefore were excluded from the analysis, 29 patients were initially treated from an endovascular approach (9 Onyx, 20 cyanoacrylate), and 4 patients were treated from a standard surgical approach. Five patients in the endovascular group subsequently underwent surgery for various reasons. The clinical improvements in the Aminoff-Logue Disability Scale gait and micturition scores, McCormick classification grading, and the mRS scores were statistically significant (P < .05, Wilcoxon signed rank test).

CONCLUSIONS

We conclude that endovascular treatment of spinal dural arteriovenous fistulas can result in good clinical outcomes. Surgery remains the treatment of choice when safe embolization of the proximal radicular draining vein cannot be obtained or because the shunting artery of the spinal dural arteriovenous fistula also supplies the anterior spinal, posterior spinal, or a radiculomedullary artery.

Arteriovenous fistula and pseudoaneurysm of the anterior spinal artery caused by an epidural needle in a 5-year-old patient

Authors present the case of a 5-year-old patient with a spinal arteriovenous fistula (AVF) and pseudoaneurysm of the anterior spinal artery (ASA) caused by a traumatic epidural needle stick injury. A discussion and relevant review of the literature follow. The boy had a remote history of a liver transplant and required neuraxial blockade for an unrelated abdominal surgical procedure. Initial insertion of the epidural needle at the T9-10 interspace yielded blood. A second attempt at T10-11 was successful. Delayed left leg weakness developed on postoperative Day 8, with an MR image showing a track injury through the cord and a ventral subarachnoid hematoma. Laminectomies from T-9 to T-11were performed emergently to decompress the spinal cord. The dura mater was opened, the ventral hematoma was evacuated, and brisk venous bleeding was controlled with cauterization. Postoperative spinal angiography demonstrated an AVF and pseudoaneurysm of the ASA. Repeat angiography at postoperative Week 4 demonstrated complete resolution of the AVF and pseudoaneurysm, probably due to intraoperative cauterization of the draining vein. The patient underwent a short course of rehabilitation and had no clinical or electrophysiological evidence of spinal cord damage at the 20-month follow-up. One should be cognizant of the possibility of a cord injury in a patient with new-onset neurological deficits following an interventional spine procedure. Neuroimaging is essential for prompt diagnosis and treatment.

Absence of abnormal vessels in the subarachnoid space on conventional magnetic resonance imaging in patients with spinal dural arteriovenous fistulas

Spinal dural arteriovenous fistula (DAVF) is an uncommon condition that can be difficult to diagnose. This often results in misdiagnosis and treatment delay. Although conventional MRI plays an important role in the initial screening for the disease, the typical MRI findings may be absent. In this article, the authors present a series of 4 cases involving patients with angiographically proven spinal DAVFs who demonstrated cord T2 prolongation on conventional MRI but without abnormal subarachnoid flow voids or enhancement. These cases suggest that spinal DAVF cannot be excluded in symptomatic patients with cord edema based on conventional MRI findings alone. Dynamic Gd-enhanced MR angiography (MRA) was successful in demonstrating abnormal spinal vasculature in all 4 cases. This limited experience provides support for the role of spinal MRA in patients with abnormal cord signal and symptoms suggestive of DAVF even when typical MRI findings of a DAVF are absent.

Surgical treatment of Type I spinal dural arteriovenous fistulas

Object

Type I spinal dural arteriovenous fistulas (SDAVFs) are low-flow vascular shunts fed by radicular arteries in patients who most often present with myelopathy. Although some fistulas are amenable to endovascular embolization, nearly all can be treated with direct microsurgical obliteration.

Methods

The authors reviewed their experience in treating 214 craniospinal arteriovenous malformations and/or fistulas over the last 8 years. Of these, 19 were spinal (9%), of which 15 (79%) were Type I SDAVFs. The authors reviewed the patients' epidemiological characteristics, presenting symptoms, and SDAVF angioarchitecture in all cases. They subsequently analyzed surgical obliteration rates and outcomes of all 11 patients who underwent fistula microsurgical obliteration.

Results

In all patients who underwent microsurgical treatment, complete angiographic obliteration of the fistula was achieved. At follow-up, 10 (91%) of 11 patients exhibited improvement, 1 patient (9%) was the same, and no patients were worse. Specifically, 8 (73%) of 11 patients had improvement in strength and sensation, 5 (71%) of 7 had improvement of bowel/bladder function, and 3 (60%) of 5 had improvement of preoperative paresthesias. There were no wound infections, CSF leaks, or permanent neurological deficits.

Conclusions

Microsurgical treatment of SDAVF provides direct access to the fistula point, allowing for high obliteration rates with excellent long-term improvement of preoperative deficits and limited periprocedural complications.

Endovascular embolization for symptomatic perimedullary AVF and intramedullary AVM: a series and a literature review

INTRODUCTION

Perimedullary arteriovenous fistula (AVF) has shunt on the spinal cord surface and it can be treated with surgery, or endovascular embolization. Intramedullary arteriovenous malformation (AVM) has its nidus in the cord and is difficult to treat either by surgery or endovascular technique. We report our experience with endovascular embolization in the treatment of perimedullary AVF and intramedullary AVM.

METHODS

Four consecutive cases of spinal perimedullary AVF and six intramedullary AVM were retrospectively reviewed. These cases were evaluated and treated at Beijing Tiantan Hospital, China, over a 2-year period. A review of previously reported cases was also performed.

RESULTS

There was no significant difference in the presentations (P = 0.348), level of lesions (P = 0.350), arterial suppliers (P = 0.801), and associated vascular anomalies between perimedullary AVF and intramedullary AVM, except for age (P = 0.014) and treatment modalities (P = 0.003). The patients with perimedullary AVFs were younger in our cases; the age at onset of symptoms averaged 25.8 years compared to 31.7 years for intramedullary AVMs. There was a significant male predominance for both lesions, and a significantly higher incidence of subarachnoid hemorrhage than in spinal dural AVFs. Regarding treatment, endovascular coil embolization is frequently used in perimedullary AVF and liquid embolic agent is an effective therapeutic choice in intramedullary AVM.

CONCLUSION

Perimedullary AVF and intramedullary AVM are dissimilar with dural AVF in clinical characteristics. Our experience suggests that the endovascular treatment of spine perimedullary AVFs and intramedullary AVMs is feasible and effective. Endovascular treatment for intramedullary AVMs is still challenging, the main problem is acute ischemia injury of the spinal cord.

Spinal arteriovenous malformation associated with spinal metameric syndrome: a treatable cause of long-term paraplegia?

Cutaneomeningospinal angiomatosis, or Cobb syndrome, is a rare metameric developmental disorder presenting as an extradural-intradural vascular malformation that involves bone, muscle, skin, spinal cord, and nerve roots. A 14-year-old girl with a red nevus involving the T6-9 dermatomes on the left side of her back presented with a 5-year history of bowel and bladder incontinence, paraplegia, and lower-extremity sensory loss. Magnetic resonance imaging demonstrated a hemangioma in the T-8 and T-9 vertebral bodies and a spinal cord AVM nidus extending from T-6 to T-9. The AVM was successfully embolized and the patient regained lower-extremity strength, ambulation, and normal sphincter functions after 5 years of having been wheelchair bound. The authors report the restoration of ambulation after endovascular embolization of a large spinal AVM in a patient with long-standing paraplegia due to Cobb syndrome.

Spontaneous occlusion of a spinal arteriovenous malformation: is treatment always necessary?

Knowledge of spinal cord arteriovenous malformations (AVMs) has recently been improved by studies on pathophysiology, neuroimaging, and genetic data. Nevertheless, the natural history of these lesions remains poorly understood.

The authors present the case of an angiographic regression of a nidal-type spinal AVM at T-12 to L-1 in a 46-year-old woman with no risk factors. The natural course of untreated lesions is reviewed and discussed. To the best of the authors' knowledge, this is the first study that reports an angiographically proven complete spontaneous occlusion of a spinal AVM.