Long-term outcome of a multidisciplinary concept of spinal dural arteriovenous fistulae treatment

Lower Cervical Dural Arteriovenous Fistula with a "Skip Lesion" in the Brainstem: A Case Report

Spinal dural arteriovenous fistulas (SDAVFs) are rare vascular malformations that can occur anywhere in the spine. Most SDAVFs lead to slow aggressive myelopathy due to venous congestion at a level adjacent to the shunt point. However, rare cases of localized brainstem edema without spinal cord lesions have been reported. In this study, we present a case of a lower cervical SDAVF that showed localized congestive edema of the medulla in the absence of an edematous change in the cervical spinal cord. The patient was a 57-year-old woman who experienced vertigo and vomiting without myelopathy that did not improve with conservative treatment. Magnetic resonance imaging (MRI) revealed high signal intensity in the left medulla on T2-weighted imaging (T2WI), while angiography revealed an SDAVF at the right C8 segmental level supplied by the right thyrocervical trunk. She underwent surgical interruption of the draining vein, which led to a rapid improvement in her symptoms. A subsequent follow-up MRI confirmed resolution of both the medullary edema and the dilated draining vein. SDAVFs may cause vertigo and vomiting, which are brainstem symptoms. Early diagnosis and surgical intervention are crucial for successful treatment outcomes.

Treatment of Dural Arteriovenous Fistula with Intradural Draining Vein at the Craniocervical Junction: Case Series with Special Reference to the Anatomical Considerations

BACKGROUND

Dural arteriovenous fistulas at the craniocervical junction (CCJ DAVFs) are a rare vascular disease. Endovascular treatment (EVT) and microsurgery are the primary treatment modalities for CCJ DAVFs. However, incomplete treatment or complications may occur after treatment because of the anatomical complexity.

OBJECTIVE

We analyzed the neurosurgical treatment experiences of CCJ DAVFs to recommend suitable classification and treatment options.

METHODS

CCJ DAVFs were anatomically classified into three types according to the feeding arteries and their relationships with the anterior spinal (ASAs) and lateral spinal arteries (LSAs). Type 1 was fed by the radiculomeningeal artery from the vertebral artery and was not associated with the ASA or LSA. Type 2 was fed by the radiculomeningeal artery, and the radicular artery supplied the LSA near the fistula point. Type 3 had the characteristics of type 1 or type 2 CCJ DAVFs, except the ASA also contributed to the fistula.

RESULTS

There were 5, 7, and 4 cases of type 1, type 2, and type 3 CCJ DAVFs, respectively. EVT was attempted in 12 patients, of whom only 1 (type 1) was completely cured without complications. Nine cases had residual lesions after EVT, and two had spinal cord infarction due to occlusion of the LSA. Fourteen patients underwent microsurgical treatment. In all 14 cases, CCJ DAVFs were completely obliterated after microsurgery.

CONCLUSION

In cases of type 1 CCJ DAVF, both microsurgical treatment and EVT may be considered. However, for type 2 and 3 CCJ DAVFs, microsurgery may be a superior treatment modality.

Recurrence Rates Following Treatment of Spinal Vascular Malformations: A Systematic Review and Meta-Analysis

BACKGROUND

Spinal vascular malformations (SVMs), including arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs), are a varied group of vascular lesions that can be subclassified according to localization, vascular structure, and hemodynamics. Early intervention is necessary to halt progression of disease and minimize irreversible dysfunction. We sought to characterize initial treatment success and recurrence rates following interventional treatment of various types of SVMs.

METHODS

A systematic review and meta-analysis were performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. SVMs were categorized into 4 groups: dural AVFs, perimedullary AVFs, intramedullary AVMs, and extradural-intradural AVMs (e.g., epidural, paraspinal). Initial occlusion, recurrence, and complication rates were compared using random-effects analysis.

RESULTS

There were 112 manuscripts included, with a total of 5626 patients with SVM. For treatment, 2735 patients underwent endovascular embolization, 2854 underwent surgical resection, and 37 underwent stereotactic radiosurgery. The initial treatment success and overall recurrence rates following surgical resection of all SVMs were 89.5% (95% CI: 80.5%-98.5%) and 2.3% (95% CI: 0.9%-3.7%), respectively. Those rates following endovascular embolization were 55.9% (95% CI: 30.3%-81.5%) and 27.7% (95% CI: 11.2%-44.2%), respectively. Higher rates of initial treatment success and lower rates of recurrence with surgery were observed in all subtypes compared to embolization. Overall complication rates were higher after embolization for each of the SVM categories.

CONCLUSIONS

Surgical resection of SVMs provided higher rates of initial complete occlusion and lower rates of recurrence than endovascular techniques. Attaining technical success through obliteration must still be weighed against clinical impact and natural history of the specific vascular malformation.

Imaging characteristics, misdiagnosis and microsurgical outcomes of patients with spinal dural arteriovenous fistula: a retrospective study of 32 patients

Background

Spinal dural arteriovenous fistula (SDAVF) is an extremely rare spinal vascular malformation. As SDAVF exhibits no specific clinical manifestations nor diverse imaging results, it is easily misdiagnosed, resulting in delayed treatment and irreversible neurological damage. Most patients were initially misdiagnosed, but there were few reports on reducing misdiagnosis.

Methods

A total of 32 consecutive patients, who presented to our institution (Shanghai Deji Hospital) with SDAVF between June 2013 and January 2016 were retrospectively analyzed. Data were collected on demographics, clinical presentation, imaging findings, follow-up, and clinical outcomes. The Aminoff-Logue scale (ALS) was used to assess clinical outcomes.

Results

Of the 32 enrolled patients (3 females, mean age 59.1±3.8 years), 23 patients (71.9%) were misdiagnosed as acute myelitis (11 patients), intramedullary tumors (6 patients), lumbar disc herniation (4 patients), and other conditions (2 patients). All patients underwent surgical procedures under electrophysiological monitoring. Fistulas were found in all 32 patients and were successfully occluded. The mean follow-up period was 19.22±8.21 months (ranging from 2 weeks to 30 months). One year later, 20 patients underwent magnetic resonance imaging (MRI), and 14 showed no T2 edema, and the edema was relieved in 6 patients. A total of 10 patients underwent enhancement MRI and no enhancement signs were detected. Among the 27 patients with long-time follow-up, the fistula had no residual or recurrence, 21 patients showed decreased ALS scores (P<0.05). Six patients exhibited nonsignificant improvement. No aggravating patient was found. Prognosis differed significantly between patients with ALS <6 and those with ALS ≥6 (P<0.05).

Conclusions

Spinal angiography should be performed with full intubation, and microcatheter angiography can reduce misdiagnosis. SDAVF must be differentiated from acute myelitis, intramedullary tumor, and other spinal vascular malformations. Microsurgical treatment is effective with a low recurrence rate.

[Clinical outcomes following microsurgery and endovascular embolization in the management of spinal dural arteriovenous fistula: A meta-analysis study]

OBJECTIVE

To compare the clinical effect of microsurgery and endovascular embolization in the treatment of spinal dural arteriovenous fistula (SDAVF) by meta-analysis.

METHODS

A systematic review was performed to retrieve all relevant literature about surgical treatment or endovascular embolization of SDAVF up to December 2019 through PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials Results, CNKI, Wanfang Data, and SinoMed. The Chinese and English key words included: "SDAVF", "spinal dural arteriovenous fistula", "spinal AVM", "spinal vascular malformation and treatment". The included studies were evaluated using the Newcastle-Ottawa scale. The early failure rate, long-term recurrence, neurological recovery, and complications were evaluated and the clinical effects of the two methods in the treatment of SDAVF were compared by using RevMan 5.3 software. And a further subgroup analysis of the therapeutic effect of endovascular embolization with different embolic agents was conducted.

RESULTS

A total of 46 studies involving 1 958 cases of SDAVF were included, in which 935 cases were treated by microsurgery and 1 023 cases were treated by endovascular embolization. The funnel plot demonstrated that there was no publication bias. The results of meta-analysis showed that the incidence of early surgical failure was lower than that of endovascular embolization (OR=0.20, 95%CI: 0.13-0.30, P < 0.05), and the long-term recurrence was also lower than that of endovascular embolization (OR=0.36, 95%CI: 0.22-0.58, P < 0.05). The improvement of neurological function in the surgical patients is significantly higher than that in the patients treated with endovascular embolization (OR=2.86, 95%CI: 1.36-5.99, P < 0.05). There was no significant difference in the occurrence of complications in these two groups (OR=1.52, 95%CI: 0.88-2.64, P=0.14). In the cases of endovascular embolization, the risk of treatment failure or recurrence was higher with Onyx glue than with n-butyl 2-cyanoacrylate (NBCA), and the difference was statistically significant (OR=4.70, 95%CI: 1.55-14.28, P < 0.05).

CONCLUSION

Although the treatment of dural arteriovenous fistulas by intravascular embolization has been widely used, the clinical effect of microsurgery is still better than that of endovascular embolization. Large scale and high-quality randomized controlled trials are required to validate the efficacy and safety of endovascular treatment in SDAVF patients.

Intraoperative Spinal Angiography during Microsurgical Occlusion of Spinal Dural Arteriovenous Fistula within the Hybrid Operation Room

BACKGROUND

 Spinal dural arteriovenous fistula (SDAVF) is a rare cause of progressive myelopathy in predominantly middle-aged men. Treatment modalities include surgical obliteration and endovascular embolization. In surgically treated cases, failure of obliteration is reported in up to 5%. The aim of this technical note is to present a safe procedure with complete SDAVF occlusion, verified by intraoperative digital subtraction angiography (DSA).

METHODS

 We describe four patients with progressive leg weakness who underwent surgical obliteration of SDAVF with spinal intraoperative DSA in the prone position after cannulation of the popliteal artery. All surgeries took place in our hybrid operating room (OR) and were accompanied by electrophysiologic monitoring. Surgeries and cannulation of the popliteal artery were performed in the prone position. Ultrasound was used to guide the popliteal artery puncture. A 5-Fr sheath was inserted and the fistula was displayed using a 5-Fr spinal catheter. Spinal intraoperative DSA was performed prior to and after temporary clipping of the fistula point as well after the final SDAVF occlusion.

RESULTS

 The main feeder of the SDAVF fistula in the first patient arose from the right T11 segmental artery, which also supplied the artery of Adamkiewicz. The second patient initially underwent endovascular treatment and deteriorated 5 months later due to recanalization of the SDAVF via a small branch of the T12 segmental artery. The third and fourth cases were primarily scheduled for surgical occlusion. Access through the popliteal artery for spinal intraoperative DSA proved to be beneficial and safe in the hybrid OR setting, allowing the sheath to be left in place during the procedure. During exposure and after temporary and permanent occlusion of the fistulous point, intraoperative indocyanine green (ICG) video angiography was also performed. In one case, the addition of intraoperative DSA showed failure of fistula occlusion, which was not visible with ICG angiography, leading to repositioning of the clip. Complete fistula occlusion was documented in all cases.

CONCLUSION

 Spinal intraoperative DSA in the prone position is a feasible and safe intervention for rapid localization and confirmation of surgical SDAVF occlusion.

Myelopathy after traumatic lumbar vertebral intraosseous arteriovenous fistula with epidural venous drainage treated with transvenous embolization

Spinal epidural arteriovenous fistulas are an uncommon entity. The authors present an interesting case of a 48-year-old man involved in a MVC five months prior to presenting with bilateral lower extremity weakness and hypoesthesia below the knees. MRI demonstrated a flow void in the L1 vertebral body burst fracture along with a dilated basivertebral vein draining in to engorged epidural venous plexus. Angiography confirmed an intraosseous arteriovenous fistula fed by T12 and L1arteries and epidural venous drainage. Complete obliteration by arterial embolization was precluded by origin of the artery of Adamkiewicz from the feeding L1 lumbar artery. Embolization using a transvenous approach allowed for successful obliteration of the fistula. Following the procedure, the patient had significant immediate improvement in the lower extremity symptoms. This is the first report of a posttraumatic spinal epidural arteriovenous fistula secondary to a vertebral burst fracture successfully treated by transvenous embolization.

Functional Outcome in Patients with Dural Arteriovenous Fistulae after Surgical Treatment

Spinal dural arterio-venous fistulas (SDAVF) are rare vascular pathologies. Degree of symptom improvement after surgery remains unclear. We evaluated surgically treated SDAVF patients for functional outcome and symptom improvement. Retrospective inclusion of consecutive patients treated surgically in our department between 2007–2019. We measured functional outcome using the McCormick Scale and modified Japanese Orthopaedic Association (mJOA) score. We included 27 patients with a median follow-up of 8.8 months (IQR 27.8). Mean age was 61.8 years (SD 8.4), 40.7% were female. Most frequent location was the thoracic spine in 15 (55.6%) followed by lumbar in 8 (29.6%), cervical in 3 (11.1%) and sacral spine in one patient (3.7%). Most common presenting symptom was progressive myelopathy (24/27 patients, 88.9%). In all patients the SDAVF was completely resected; however, four patients (14.8%) required a second surgery. Six patients (22.2%) deteriorated immediately after surgery with five recovering to baseline upon discharge. On discharge, presenting symptoms had improved in 17 patients (63%); 8/25 patients (32%) had a McCormick score of 1. Twenty (74.1%) continued to improve on follow-up. In total 23/27 patients (85.2%) improved. In the univariable analysis mJOA score on admission was associated with mJOA score on follow-up (coefficient 0.6, 95%CI 0.4–0.81, p < 0.001), whereas age was inversely associated (coefficient −0.1, 95%CI −0.19–0.01, p = 0.08). Untreated SDAVF leads to progressive myelopathy which may result in considerable disability. Surgical disconnection and resection provides a safe treatment option with low perioperative morbidity and excellent chances for symptom improvement or progression prevention.

Long-term surgical outcomes of patients with delayed diagnosis of spinal dural arteriovenous fistula

Spinal dural arteriovenous fistula (dAVF) is an extremely rare vascular entity that is usually misdiagnosed. We sought to determine the long-term clinical outcomes of patients undergoing microsurgical treatment for delayed diagnosis of spinal dAVF. This retrospective study identified patients with delayed diagnosed spinal dAVF at our institution from 2009 to 2018. Patients' data, including demographics, imaging, and follow-up data, were evaluated. This cohort included 65 consecutive patients with 68 dAVFs and a male-to-female ratio of 4:1 and a mean age of 53.5 ± 13.7 years. The presenting symptoms consisted of limb weakness (n = 42, 64.6%), paraparesis (n = 34, 52.3%), sphincter disturbances (n = 8, 12.3%), and pain (n = 13, 20.0%). The proportion of patients with each symptom significantly increased and patients experienced increased disability when the diagnosis was finalized. The mean length of delay of diagnosis was 20.7 ± 30.0 months. Surgery resulted in complete occlusion of the fistula on the first attempt in all patients. Three patients developed recurrent fistulas, and three died in the follow-up period. Improved motor function was achieved in 38 patients (59.5%). Other symptoms, such as sensory disorders, sphincter dysfunction, and pain, improved by 37.3%, 32.3%, and 66.7%, respectively. Patients with spinal dAVF usually exhibit progressive ascending myelopathy and often remain misdiagnosed for months to years. Some patients' increased disability cannot be reversed through surgery.

Clinical characteristics, misdiagnosis and outcomes of patients with low-flow spinal arteriovenous fistulas

OBJECTIVE

To describe the clinical characteristics, delay to diagnosis and post-intervention outcomes of patients with low-flow spinal arteriovenous fistulas (SAVFs).

METHODS

In this retrospective observational study, we reviewed all patients with low-flow SAVFs angiographically diagnosed at our institution between 2008 and 2018. Pre- and post-intervention disability levels were recorded using the modified Aminoff and Logue scale (mALS).

RESULTS

One-hundred and five patients were included. Median age was 62 years and 79% were male. Most patients (56%) presented to neurologists and 41% were misdiagnosed with myelitis. Patients underwent unnecessary treatment with corticosteroids (44%), other immunosuppressive therapies (8%) and spinal surgery (10%). Inappropriate corticosteroid treatment led to a precipitous clinical decline in 30% of patients exposed. Only 21% percent of patients were correctly diagnosed after initial evaluation; the median delay to diagnosis in the rest of the cohort was of 12 months (IQR 7 to 24 months). Longer delays to diagnosis were associated with higher levels of disability (p = .002). Treatment of SAVF was endovascular in 64% and surgical in 26%; 13% of patients required further intervention due to incomplete initial treatment or fistula recurrence. Greater than 6 months after intervention, disability scores were improved in 52% and stable in 43% of patients. In individual patients, pre- and post-intervention disability scores were strongly correlated (p < .001).

CONCLUSIONS

Low-flow SAVFs are associated with substantial disability and are frequently misdiagnosed. Timely diagnosis of SAVF needs to improve, as endovascular or surgical treatment results in stabilization or improvement of disability in the vast majority of patients.

Long-Term Outcome of Patients with Spinal Dural Arteriovenous Fistula: The Dilemma of Delayed Diagnosis

BACKGROUND AND PURPOSE

The impact of various radiologic and clinical features on the long-term outcome in spinal dural arteriovenous fistulas is still unclear; thus, they are the purpose of this study.

MATERIALS AND METHODS

We retrospectively analyzed our medical data base for all patients treated for spinal dural arteriovenous fistula in our institution between 2006 and 2016. Patient age, neurologic status at the time of diagnosis, the duration of symptoms from onset to diagnosis, and follow-up information were evaluated. The extent of medullary T2WI hyperintensity, intramedullary contrast enhancement, and elongation of perimedullary veins on MR imaging at the time of diagnosis were additionally analyzed.

RESULTS

Data for long-term outcome analysis were available in 40 patients with a mean follow-up of 52 months (median, 50.5 months; range, 3-159 months). The mean age at the time of diagnosis was 69.27 ± 9 years (median, 71 years; range, 53-84 years) with a male predominance (n = 32; 80%). The mean duration of symptoms was 20.2 months (median, 10 months; range, 1-120 months). Shorter duration of symptoms at the time of diagnosis was significantly correlated with better outcome of symptoms (P < .05).

CONCLUSIONS

Spinal dural arteriovenous fistulas are characterized by interindividually variable clinical presentations, which make a determination of specific predictors for long-term outcome more difficult. Fast and sufficient diagnosis might result in a better outcome after treatment. The diagnosis of spinal dural arteriovenous fistula remains markedly delayed, reflecting an ongoing lack of knowledge and awareness among treating physicians of this rare-but-serious disease.

Successful surgical strategy for ventral thoracic spinal perimedullary spinal arteriovenous fistulas: Case report

Background:

Spinal arteriovenous fistulas (AVFs) are vascular lesions that often pose significant surgical challenges. This is particularly true for those located close to the anterior spinal artery. Here, we analyzed the surgical options for treating an anterior perimedullary AVF (pAVFs).

Case Description:

A 66-year-old male with the right lower extremity weakness was diagnosed with a spinal dural AVF at the L1 level. It was initially treated with open surgery followed by CyberKnife radiosurgery at another institution. Five years later, he presented with a persistent pAVF fistula now involving the T11 level; the major feeder originated on the left at the T7–T8 level (e.g., involving a left-sided “duplicated” anterior spinal artery). Utilizing a three-dimensional (3D) computer tomography (CT) guided approach; he underwent a left-sided posterolateral T10–T12 laminectomy, sufficient to allow for 30–40° of anterior spinal cord rotation. This was performed under neurophysiological monitoring without any significant changes. Surgery included indocyanine green video angiography, temporary feeder clipping, and complete occlusion of the AVF, followed by complete clipping/resection as confirmed on postoperative magnetic resonance imaging.

Conclusion:

Utilizing a 3D CT image, a ventral pulmonary arteriovenous malformation was excised utilizing a left-sided posterolateral approach allowing for 30–40° of cord rotation.

Treatment strategy and long-term outcome in patients with deep lumbosacral arteriovenous fistulas. A single center analysis in nineteen patients

OBJECTIVE

Deep lumbosacral dural arteriovenous fistulas (lsDAVF) are rare and present serious diagnostic and treatment difficulties. In our current analysis we present our treatment strategy and the long-term clinical outcome of nineteen patients with lsDAVF.

PATIENTS AND METHODS

We retrospectively analyzed our radiological and medical records for patients presenting with SDAVF between 1990 and 2018 at the University Hospital Aachen. We identified twenty patients with a lsDAVF. All patients were treated surgically. One patient died of pulmonary embolism three months after treatment and was excluded from our outcome analysis. Clinical data at time of admission, discharge, one year after discharge and at the last follow-up were evaluated according to modified Aminoff-Logue disability score (AL-score) for this analysis.

RESULTS

Mean age was 65 ± 7 years (median, 67; range, 53-78), sixteen patients (84 %) were male. After surgery, four patients developed a recurrent fistula in the same shunt zone and were re-treated microsurgically. Follow-up data one year after treatment was available in 15 patients. No relevant changes in AL-score were observed within this period. For the long-term follow-up analysis, data of 13 patients were available; 38.5 % of patients developed late functional deterioration.

CONCLUSION

In our cohort, patients with deep lumbosacral dural arteriovenous fistula had a higher risk of early recurrence compared to patients with thoracolumbar SDAVF, with a considerable percentage of late functional deterioration. Thus strict clinical and radiologic long-term follow-up examinations are recommended in those patients.

Clinical and neuroimaging findings of spinal dural arteriovenous fistulas: How to avoid misdiagnosis of this disease

OBJECTIVE

Spinal dural arteriovenous fistulas (DAVFs) are rare but can cause serious gait and micturition disturbances. Delays in diagnosis and treatment result in poor clinical outcomes; however, the process of misdiagnosis is unknown.

METHODS

Forty consecutive patients were retrospectively analyzed.

RESULTS

Thirty-one patients (78%) were initially misdiagnosed with lumbar spinal stenosis or other diseases, mostly by orthopedic surgeons, even though most patients (85%) had specific symptoms or characteristic neuroimaging findings of spinal DAVFs: they often presented with spastic gait (thoracic myelopathy), progressive ascending numbness that begins in the distal lower extremities (epicous syndrome), and urinary tract symptoms (conus medullaris syndrome); initial lumbar MRI showed T2 signal change in the conus medullaris and vascular flow voids around the cord. The median time from onset to treatment was longer in patients with a misdiagnosis than in those with the correct diagnosis (11 vs 4 months). In all patients, the fistula was completely obliterated by the direct microsurgical procedure; however, patients with a misdiagnosis had developed additional disabilities by the time a correct diagnosis was made (Aminoff-Logue gait grade of 3.6 ± 1.4 vs 2.1 ± 1.5 p = 0.013), and achieved markedly smaller improvements after the treatment (Aminoff-Logue gait grade of 3.0 ± 1.6 vs 1.1 ± 1.5, p = 0.006) than those with the correct diagnosis of spinal DAVFs.

CONCLUSIONS

When common spinal stenosis fail to explain the symptoms such as thoracic myelopathy, epiconus syndrome, and conus medullaris syndrome, the possibility of spinal DAVFs should be considered. If lumbar MRI shows conus medullaris lesions, thoracic MRI should be performed to confirm the diagnosis.

Outcomes following surgical versus endovascular treatment of spinal dural arteriovenous fistula: a systematic review and meta-analysis

Although surgical resection is associated with a complete cure in most cases of spinal dural arteriovenous fistulas (SDAVF), there has been an increasing trend towards embolisation. We performed a systematic review and meta-analysis comparing surgical resection with endovascular treatment in terms of success of treatment, rate of recurrence and complications. A literature search was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Strength of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation Working Group system. Surgical outcomes such as initial treatment failure, late recurrence, neurological improvement and complications were compared between the two approaches. We included 57 studies with 2029 patients, of which 32 studies with 1341 patients directly compared surgery (n=590) and embolisation (n=751). Surgery was found to be associated with significantly lower odds of initial treatment failure (OR: 0.15, 95% CI 0.09 to 0.24, I² 0%, p<0.001) and late recurrence (OR 0.18, 95% CI 0.09 to 0.39, I² 0%, p<0.001). The odds of neurological improvement following surgery were also significantly higher compared with embolisation alone (OR: 2.73, CI:1.67 to 4.48, I² :49.5%, p<0.001). No difference in complication rates was observed between the two approaches (OR 1.78, 95% CI 0.97 to 3.26, I² 0%, p=0.063). Onyx was associated with significantly higher odds of initial failure/late recurrence as compared with n-butyl 2-cyanoacrylate (OR: 3.87, CI: 1.73 to 8.68, I² :0%, p<0.001). Surgery may be associated with superior outcomes for SDAVFs in comparison to endovascular occlusion. Newer embolisation agents like Onyx have not conferred a significant improvement in occlusion rate.

Coil-Protected Technique for Liquid Embolization in Neurovascular Malformations

OBJECTIVE

To evaluate the safety and efficacy of the coil-protected technique for liquid embolization in neurovascular malformations.

MATERIALS AND METHODS

Twenty-two patients who underwent coil-protected liquid embolization for symptomatic cranial (n = 13) and spinal (n = 9) arteriovenous fistula (AVF) or arteriovenous malformations (AVMs) were identified. A total of 36 target feeder vessels were embolized with N-butyl cyanoacrylate and/or Onyx (Medtronic). This technique was used to promote delivery of a sufficient amount of liquid embolic agent into the target shunt or nidus in cases where tortuous feeding arteries preclude a microcatheter wedging techniqu and/or to prevent reflux of the liquid embolic agent in cases with a short safety margin. The procedure was considered technically successful if the target lesion was sufficiently filled with liquid embolic agent without unintentional reflux. Angiographic and clinical outcomes were retrospectively evaluated.

RESULTS

Technical success was achieved for all 36 target feeders. Post-embolization angiographies revealed complete occlusion in 16 patients and near-complete and partial occlusion in three patients each. There were no treatment-related complications. Of the six patients who showed near-complete or partial occlusion, five received additional treatments: two received stereotactic radiosurgery for cerebral AVM, two underwent surgical removal of cerebral AVM, and one underwent additional embolization by direct puncture for a mandibular AVM. Finally, all patients showed complete (n = 19) or near-complete (n = 3) occlusion of the target AVF or AVM on follow-up angiographies. The presenting neurological symptoms improved completely in 15 patients (68.2%) and partially in seven patients (31.8%).

CONCLUSION

The coil-protected technique is a safe and effective method for liquid embolization, especially in patients with various neurovascular shunts or malformations who could not be successfully treated with conventional techniques.

The clinical value of venous drainage in patients with spinal dural arteriovenous fistula

BACKGROUND

Spinal dural arteriovenous fistulas (sdAVF) with rapid deterioration are a known clinical phenomenon but have been rarely reported in the past. Clinical and radiologic features of these fistulas are analyzed for this study.

MATERIAL AND METHODS

We retrospectively reviewed our medical records for sdAVF patients who were treated in our center between 2006 and 2017. Our cohort was dichotomized in two groups; a) patients with acute/ subacute onset and rapid deterioration within a period of ≤6 months, b) patients with chronic progressive deterioration within a period of >6 months. MR findings at time of diagnosis were re-evaluated. All patients were treated microsurgically. Follow-up data were included.

RESULTS

Data of forty patients were available for this study. Rapid deterioration was observed in 13/40 (32.5%) patients. AL-score at time of diagnosis did not differ between both groups (3.2 ± 1.2 vs 3 ± 2, p = .78). Patients with rapid deterioration showed significantly more prominent arterialized perimedullay veins at time of diagnosis (p < .05). At the last follow-up (53 ± 3 months), patients with rapid deterioration improved up to one point on AL-scores (from 3.2 ± 1.4 to 2 ± 1.6) and those with chronic progressive deterioration were unchanged (from 3 ± 1.6 to 3 ± 1.7).

CONCLUSION

Patients with rapid deterioration in our group (32.5%) presented with a significantly more prominent appearance of the arterialized perimeduallry veins. This may reflect, in the earlier phase of the disease, a better compensation of the venous hypertension as well as the associated venous outlet disorder of the spinal cord. This may also explain the better outcome of these patients.

Comparison of Endovascular Embolization and Surgery in the Treatment of Spinal Intradural Dorsal Arteriovenous Fistulas

BACKGROUND

We compared the outcomes of endovascular embolization and surgery and investigated the factors affecting the clinical outcomes of spinal intradural dorsal arteriovenous fistulas (SIDAVFs).

METHODS

The medical records of 26 patients who had undergone endovascular embolization or surgery for SIDAVFs from 2004 to 2014 were retrospectively reviewed. The recurrence rate and clinical outcomes for each treatment modality were compared. Multivariate analysis was used to identify significant factors influencing the clinical outcomes using the Aminoff and Logue (AL) score.

RESULTS

Of the 26 patients, 14 (56%) had undergone endovascular embolization and 11 (44%) had undergone surgery as the initial treatment. Embolization was applied as the primary treatment for most patients. Surgery was chosen for patients with difficult superselection (n = 5), multiple feeders (n = 2), or easy surgical accessibility (n = 4). Of the 14 patients who had undergone embolization as initial treatment, 5 (36%) had developed a recurrence within an average of 29.6 months (range, 2-87). One patient with recurrent SIDAVF was treated with repeat embolization and four with surgery. None of patients in the surgical group developed recurrence. Embolization as the initial treatment resulted in significantly greater recurrence compared with surgery (odds ratio, 2.222; 95% confidence interval, 1.369-3.608; P = 0.046). Surgery resulted in better clinical outcomes than embolization (P = 0.021). The final AL score was also strongly affected by the preoperative AL score, micturition score, and recurrence (P = 0.000, P = 0.000, and P = 0.011, respectively).

CONCLUSIONS

Our results have shown that surgery results in a low recurrence rate and superior clinical outcomes. A multidisciplinary and ordered decision is crucial for the treatment choice to ensure better outcomes, especially for patients with a definite neurologic deficit at diagnosis.

Double spinal dural arteriovenous fistulas

BACKGROUND

Spinal dural arteriovenous fistulas (SDAVF) are usually solitary lesions. Synchronous and/or metachronous double SDAVF have rarely been reported in the literature. We report on three patients with double SDAVF and present our single center experience in the diagnostic and treatment management in these patients.

MATERIAL AND METHODS

We retrospectively revised our medical database for all patients who were diagnosed and treated in our center due to a SDAVF between 1990 and 2017. All data including demographics, clinical presentations, as well as radiological data were re-evaluated for this study.

RESULTS

Three (1.4%) of 209 consecutive patients with SDAVF presented double SDAVF with different arterial feeders and venous drainage patterns. All three patients were men. The mean age at time of diagnosis was 67.9 ± 10 years (median; 68, range: 53-82). Myelopathic symptoms were reported in all three cases. All three fistulas were located in the thoracolumbar region between T7 and L2. MRI/CE-MRA showed medullar T2-hyperintensity, intramedullary contrast-enhancement and dilatation of perimedullary veins in various extensions.

CONCLUSION

Double SDAVF are extremely rare and were found in 1.4% of patients in our series. The vast majority of the reported double SDAVF in the literature has been detected synchronously within an area of equal or less than three vertebral levels. Thus, whenever the SDAVF is identified, further injections of the fistula-zone neighbored segmental arteries might be recommended. However, due to the extremely low incidence of double SDAVF a complete spinal DSA is not indicated.

The Hybrid Assistive Limb® intervention for a postoperative patient with spinal dural arteriovenous fistula and chronic spinal cord injury: A case study

CONTEXT

The purpose of this report was to describe the improvement in walking ability using the Hybrid Assistive Limb® (HAL®) intervention in the case of a patient with paraplegia after spinal cord injury whose condition deteriorated because of a spinal dural arteriovenous fistula (SDAVF).

FINDINGS

A 48-year-old man started the HAL® intervention twice per week (total 10 sessions), after his neurologic improvement had plateaued from 3 to 6 months postoperatively for an SDAVF. During the HAL® intervention, the 10-m walk test (10MWT) without HAL® was performed before and after each session. An electromyography system was used to evaluate muscle activity of both the gluteus maximus (Gmax) and quadriceps femoris (Quad) muscles in synchronization with the Vicon motion capture system. The International Standards for Neurological and Functional Classification of Spinal Cord Injury (ISNCSCI) motor scores of the lower extremities and the Walking Index for Spinal Cord Injury II (WISCI II) score were also assessed to evaluate motor function. The HAL® intervention improved gait speed and cadence during the 10MWT. Before the intervention, both the Gmax and left Quad muscles were not activated. After the intervention, the right Gmax and both Quad muscles were activated in stance phase rhythmically according to the gait cycle. The ISNCSCI motor score also improved from 14 to 16, and the WISCI II scored improved from 7 to 12.

CONCLUSION/CLINICAL RELEVANCE

Our experience with this patient suggests that the HAL® can be an effective tool for improving functional ambulation in patients with chronic spinal cord injury.

Dual-lumen balloon to increase onyx venous penetration in the treatment of spinal dural arteriovenous fistulas

PURPOSE

Spinal dural arteriovenous fistulas (sDAVF) are the most common spinal vascular lesions. The arterialization of the recipient vein results in venous hypertension and chronic ischemia. Intravascular injection of acrylic glue in order to occlude the draining vein is the principle of endovascular treatment, but a significant portion of embolization procedures do not succeed. We present our initial experience of endovascular balloon augmented embolization of sDAVF using a dual-lumen balloon.

CLINICAL PRESENTATION

Three patients harboring sDAVF were submitted to endovascular treatment by onyx injection assisted by a double-lumen balloon as the sole therapy. Control angiography demonstrated complete obliteration of the fistula in all cases with clinical improvement.

CONCLUSION

Dual-lumen balloon onyx embolization of spinal dural arteriovenous fistulas appears to be an acceptable and feasible alternative.

Induced-Wedge Technique to Improve Liquid Embolic Agent Penetration into Spinal Dural Arteriovenous Fistula

OBJECTIVE

To promote embolization of spinal dural arteriovenous fistula (SDAVF) with a small long tortuous feeder that may impede successful application of an embolic agent.

METHODS

An induced-wedge technique was developed in which blood flow was blocked by coiling at the proximal part of the microcatheter for secure injection of N-butyl cyanoacrylate. We used this technique in 11 patients with SDAVF (male/female ratio, 8:3): 7 thoracic, 2 lumbar, 1 sacral, and 1 cervical. Clinical outcome was evaluated by the Aminoff-Logue Disability Scale.

RESULTS

Penetration of embolic agent through the fistula into the vein was complete (n = 5), nearly complete (no penetration of embolic agent into the vein but no residual fistula on 3 adjacent selective angiograms; n = 4), or partial (embolization with a small residual filling of the draining vein; n = 2). All patients improved neurologically during follow-up (median, 18 months; range, 7-37 months) and achieved complete recovery. Of the 2 patients who obtained partial obliteration, one showed disappearance of the residual lesion on angiography 21 months later and the other achieved complete results after repeat embolization.

CONCLUSIONS

The induced-wedge technique can improve SDAVF embolization by providing better penetration of the liquid embolic agent to the fistula and vein.

Clinical Characteristics and Treatment Outcomes of Spinal Arteriovenous Malformations

PURPOSE

Spinal arteriovenous malformations (SAVMs) are rare events. This study evaluated initial clinical presentations and treatment outcomes of SAVMs.

METHODS

In this study, 91 consecutive patients with SAVM between January 1993 and November 2014 were evaluated. Initial clinical presentations, radiological findings, treatment results, and follow-up outcomes were evaluated according to disease type and treatment modalities. Patient status was scored using the modified Rankin scale (mRS) and Aminoff-Logue Disability scale (ALS).

RESULTS

Of the SAVM patients 69 % were male and 31 % were female with a mean age of 49 years (range 11-82 years). At the time of initial imaging evaluation, myelopathy was the most common finding with main complaints of gait disturbance (69 out of 91, 76 %), sensory disturbances (61/91, 67 %), and bowel or bladder symptoms (51/91, 56 %). Among the 80 patients who received treatment 56 (62 %) underwent endovascular embolization and 24 (26 %) underwent surgery. Complete obliteration was achieved in 47 patients (84 %) after endovascular embolization and in 18 (75 %) after surgical ligation. At the time of final follow-up 67 patients (84 %) showed improvement of more than 1 point on the mRS, while 69 (86 %) showed significant improvement on the ALS after treatment.

CONCLUSION

The SAVMs presented with diverse neurological deficits, including myelopathy. Endovascular or surgical treatment of SAVMs can result in good clinical outcomes in most patients.

Health-related quality of life in patients with spinal dural arteriovenous fistulae

Neurological improvement in patients with spinal dural arteriovenous fistulae (SDAVF) is often partial even after adequate treatment. While treatment outcomes have been evaluated primarily on the basis of the postoperative changes in neurological deficits, outcome measures should also reflect the patient-reported outcome (PRO). We conducted a health-related quality of life (HRQOL) survey in 52 SDAVF patients; 33 (63.5%) completed the short-form 36 Health Survey (SF-36) questionnaire. They were 25 males and 8 females ranging in age from 47 to 85 years (mean age 70.0 years). The mean follow-up period was 95.6 months. We analyzed the completed questionnaires and examined the clinical factors associated with their HRQOL. After treatment, gait- and micturition disturbances persisted in 31 (93.9%) and 31 (93.9%) of our patients; 26 (78.8%) reported chronic leg pain. The SF-36 scores of treated SDAVF patients were significantly lower than the national average of 50 for all 8 sub-items in the questionnaire. The scores for physical functioning (PF) and role-physical (RP) were particularly low. With the exception of bodily pain (BP), there was a significant negative correlation between the Aminoff-Logue scale (ALS) scores for gait- and micturition and the sub-item scores. The score for BP showed a significant positive correlation with the scores for the 7 other SF-36 sub-items. The HRQOL of treated SDAVF patients was lower than the national average with respect to both physical and mental aspects. Persistent post-treatment pain and gait- and micturition disturbances were responsible for their lower HRQOL.

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.

Recurrence Rates After Surgical or Endovascular Treatment of Spinal Dural Arteriovenous Fistulas: A Meta-analysis

BACKGROUND

There is an increasing tendency to treat spinal dural arteriovenous fistulas (SDAVFs) endovascularly despite the lack of clear evidence favoring embolization over surgery.

OBJECTIVE

To compare the initial failure and recurrence rates of primary treatment of SDAVFs by surgery and endovascular techniques.

METHODS

A meta-analysis using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) standard was performed. All the English literature from 2004 onward was evaluated. From each article that compared the 2 treatment modalities, the odds ratio (OR) was calculated. Combined ORs were calculated with Review Manager 5.3 of The Cochrane Collaboration.

RESULTS

A total of 35 studies harboring 1112 patients were assessed. Initial definitive fistula occlusion was observed in 588 of 609 surgical patients (96.6%; 95% confidence interval [CI], 94.8-97.8) vs 363 of 503 endovascularly treated patients (72.2%; 95% CI, 68.1-75.9; P < .001). The combined OR from 18 studies that assessed both treatment modalities (730 patients) was 6.15 (95% CI, 3.45-11.0) in favor of surgical treatment. Late recurrence (13 studies, 480 patients) revealed an OR of 3.15 (95% CI, 1.66-5.96; P < .001) in favor of surgery. In a subgroup, recurrence was reported in 10 of 22 patients (45%) treated with Onyx vs 8 of 35 (23%) treated with n-butyle-2-cyanoacrylate (OR, 2.51; 95% CI, 0.75-8.37; P = .13).

CONCLUSION

Although hampered by inclusion of poor quality studies, this meta-analysis shows a definite advantage of primary surgical treatment of SDAVF over endovascular treatment in initial failure rate and late recurrences. The often-used argument that endovascular techniques have improved and therefore outweigh surgery is not supported by this meta-analysis.

A Survey of Chronic Pain Due to Spinal Dural Arteriovenous Fistulae

BACKGROUND

Chronic pain due to spinal dural arteriovenous fistulae (SDAVF) during follow-up is a serious issue because it can affect patients' quality of life. The severity of posttreatment chronic leg pain in patients with SDAVF is unclear.

OBJECTIVE

To investigate the prevalence, severity, and characteristics of chronic leg pain in patients with SDAVF and to examine the clinical factors associated with chronic pain.

METHODS

We conducted a survey of their chronic posttreatment leg pain in 49 SDAVF patients. It consisted of a numeric rating scale and a neuropathic pain symptom inventory (NPSI). Of the 49 patients, 32 (65.3%) completed the questionnaire. There were 24 males and 8 females whose mean age was 69.1 years. The mean follow-up period was 86.3 months.

RESULTS

Chronic leg pain was reported by 26 (81.3%) of 32 patients; 14 experienced pain before treatment and 12 had new-onset posttreatment pain. The pain was reported as moderate to severe by 21 (80.8%) of 26 patients; the mean numeric rating scale and NPSI scores were 6.0 ± 2.3 and 17.4 ± 10.3, respectively. The NPSI subscores were significantly higher for spontaneous pain and paresthesia/dysesthesia than for paroxysmal pain. We found no significant clinical factors related to chronic posttreatment pain; on magnetic resonance imaging scans we identified spinal cord atrophy in 8 patients with chronic pain.

CONCLUSION

Most of our SDAVF patients reported moderate to severe chronic leg pain characterized by spontaneous pain and paresthesia/dysesthesia. Spinal cord atrophy on magnetic resonance imaging scans was a characteristic in patients with chronic pain.

Spinal Dural Arteriovenous Fistula: A Review

Spinal dural arteriovenous fistula (SDAVF) is a rare disease, the etiology of which is not entirely clear. It is the most common vascular malformation of the spinal cord, comprising 60-80 % of the cases. The clinical presentation and imaging findings may be nonspecific and misleading, often mistaking it for other entities like demyelinating or degenerative diseases of the spine.This chapter describes the imaging findings, clinical signs, and symptoms of this disease and also the available treatment options according to the current literature.Angiography is still considered the gold standard for diagnosis; however, MRI/MRA is increasingly used as a screening tool. Modern endovascular techniques are becoming increasingly more effective in treating SDAVF offering a less invasive treatment option; however, they still lag behind surgical success rates which approach 100 %. The outcome of both treatment options is similar if complete obliteration of the fistula is obtained and depends mainly on the severity of neurological dysfunction before treatment.Heightened awareness by radiologists and clinicians to this rare entity is essential to make a timely diagnosis of this treatable disease. A multidisciplinary treatment approach is required in order to make appropriate treatment decisions.

Microvascular anatomy of spinal dural arteriovenous fistulas: arteriovenous connections and their relationships with the dura mater

OBJECT The microvascular anatomy of spinal dural arteriovenous fistulas (AVFs), especially the relationships of the vessels with the dura mater, has yet to be angiographically demonstrated in detail and proven histologically. METHODS From January 2012 through April 2014, a total of 7 patients with spinal dural AVFs in the thoracic region underwent open microsurgical obliteration at Tokyo Metropolitan Neurological Hospital. The microvascular anatomy of spinal dural AVFs was comprehensively assessed by using advanced microangiography, including 3D computer graphics and intraoperative indocyanine green video angiography, and by histological findings. RESULTS The 2 microangiography techniques revealed the spatial course and in vivo blood flow of the meningeal vessels and their relationships with the dura mater in sufficient detail. The meningeal branch of the intercostal artery split into multiple meningeal vessels on the outer dural surface adjacent to the root sleeve. After crossing the dura mater to the inner dural surface, these vessels gathered and joined a single intradural draining vessel. On the inner dural surface, the single draining vessel was fed by the surrounding multiple meningeal vessels, which appeared to be caput medusae. Histological findings revealed that the structure of the meningeal branch of the intercostal artery corresponded to that of a normal artery. The structure of intradural draining vessels corresponded to that of a vein modified by retrograde arterial inflow. On the inner dural surface, more than 1 meningeal artery gathered and joined with the proximal radiculomedullary vein. CONCLUSIONS Spinal dural AVFs are located on the inner dural surface, where multiple direct AV connections between more than 1 meningeal feeding artery and a single proximal radiculomedullary vein occur at the site where the vein connects to the dura mater.

Surgical management of spinal dural arteriovenous fistulas

Spinal dural arteriovenous fistulas are the most common type of spinal arteriovenous malformations. Treatment options consist of microsurgical exclusion and/or endovascular embolization. We retrospectively identified all patients who benefited from surgical treatment at our tertiary center between January 2001 and December 2008. Clinical and imaging data were collected from patient files, including pre- and post-operative formal neurological examination, complete spine MRI and spinal digital subtraction angiography. Of our 30 patients, 25 were men and five were women with a median age of 62 years (range 24-76). The average delay between symptom onset and clinical diagnosis was 27 months (range 1-90). Complete cure of the fistula was obtained in all patients in a single surgical session with no procedural complications and no surgical morbidity. After a mean follow-up period of 32 months (range 14-128), 25 patients (83%) had improved, four were stable and one worsened. Despite recent advances in endovascular techniques and materials, there is a subgroup of patients for which surgery remains the best treatment option. Careful patient selection, a multidisciplinary approach and standardized surgical techniques can lead to excellent results with virtually no complications.

Guidelines for the use of NBCA in vascular embolization devised by the Committee of Practice Guidelines of the Japanese Society of Interventional Radiology (CGJSIR), 2012 edition

Cyanoacrylates are a group of fast-acting adhesives. They form low viscosity liquids in the monomer state and instantly polymerize to become adhesive upon contact with ionic substances. Since the 1950s, they have been used around the world for industrial and household purposes. N-butyl cyanoacrylate (NBCA) is a cyanoacrylate that is commonly used for medical care, and the closure of skin wounds with NBCA has been found to promote hemostasis. However, in Japan, the intravascular injection of NBCA is considered to be off-label use, except during the treatment of gastric varices under endoscopy. The use of NBCA in embolotherapy is considered when the target vessels cannot be cannulated superselectively, for vascular diseases that require long segments of the target vessel to be embolized, or for patients in a hypocoagulable state. NBCA-based embolotherapy can be used to treat vascular malformations, acute hemorrhaging, tumors, and venous disease. The complications associated with NBCA-based embolotherapy include tissue ischemia, hemorrhaging, systemic or local reactions, and catheter adhesion to blood vessels. NBCA is mixed with Lipiodol to make it radiopaque and to adjust its polymerization time. Since there are various technical aspects to performing NBCA-based embolotherapy safely, it should be carried out by, or with the assistance of, proficient interventional radiologists.

Correlation between time to diagnosis and rehabilitation outcomes in patients with spinal dural arteriovenous fistula

BACKGROUND

Spinal dural arteriovenous fistulas (SDAVFs) are the most common spinal vascular malformations and can be a significant cause of myelopathy although they are under diagnosed. Surgical or embolization treatment of SDAVFs improved significantly in the last decade. However, a high percentage of patients are still left with severe disability.

OBJECTIVE

To describe the correlation between time to diagnosis and the rehabilitation outcomes of eight patients with SDAVFs.

DESIGN

Retrospective chart study of all SDAVF patients in 20 years.

SETTING

A tertiary university rehabilitation center.

MAIN OUTCOME MEASURES

The lower extremities motor score (LEMS), Functional Independence Measure (FIM), Spinal Cord Independence Measure (SCIM) and Walking Scale for Spinal Cord Injury (WISC II). Overall prognosis was evaluated using the Aminoff-Logue scale (ALS).

RESULTS

There were seven men and one woman with mean age of 61.3 ± 15 (30-72) and mean time until the diagnosis of SDAVF of 265.5 ± 245 days (4-730). At the end of rehabilitation period, five of the eight patients remained wheelchair dependent. Strong correlation was found between LEMS, FIM, SCIM, and WISC II scores and the functional level according to the ALS scale. A significant correlation was found between time to diagnosis and the height of the SDAVF, the clinical and rehabilitation outcomes. Patients with high SDAVF which were diagnosed late had the poorest prognosis.

CONCLUSIONS

The potential for functional ambulation in patients with SDAVF is related to the time of intervention. This finding emphasizes the important of early diagnosis and early intervention in SDAVF.

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.

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.

Clinical outcome of treatments for spinal dural arteriovenous fistulas: results of multivariate analysis and review of the literature

STUDY DESIGN

This study was a case series study using a prospective single-institute database for the treatment of spinal dural arteriovenous fistulas (SDAVFs).

OBJECTIVE

To evaluate clinical factors that influence the neurological outcomes of treatment for SDAVFs, which were obtained from the analysis of 21 patients treated in our institution, and to provide management recommendations based on the review of former major clinical studies including our own reported over the past 2 decades.

SUMMARY OF BACKGROUND DATA

Since 1977, when Kendall and Logue described the etiology of SDAVFs as hyperpressure of intrathecal veins due to an abnormal shunting from the arteries, treatment strategies have improved dramatically along with developments in neuroimaging, endovascular techniques and materials, and microsurgery based on the underlying pathophysiological process. However, therapeutic guidelines remain controversial.

METHODS

Patients treated for SDAVFs from 2000 to 2008 were eligible. Age, sex, level of shunting, initial symptom, duration of symptom, the treatment method, and clinical symptoms before and 6 months after treatment were investigated.

RESULTS

There were a total of 30 patients (18 male and 12 female), with a mean age of 59 years; 21 of them underwent treatment for the first time. We conducted a univariate analysis using a logistic regression model, on age, sex, the level of SDAVFs, duration of symptoms, symptom (sensory or paralysis), and gait function and micturition before treatment, and the intervention method were set as variables to investigate the risk factors for motor deficit 6 months after the treatment. Only gait function before treatment was correlated with the motor deficit 6 months after treatment (odds ratio = 10.0; 95% confidence interval = 1.28-78.11, P = 0.03).From these results, intervention at an early stage would be the key to a preferable outcome of the treatment for SDAVFs.

CONCLUSION

The clinical status before treatment significantly influenced the clinical outcome after the treatment.

Surgical treatment of spinal dural arteriovenous fistulae: a consecutive series of 154 patients

BACKGROUND

Embolization of spinal dural arteriovenous fistulae (SDVAFs) has emerged as an alternative to surgery. However, surgical disconnection is a simple and effective procedure.

OBJECTIVE

To review results and complications of surgical treatment of 154 consecutive SDAVFs.

METHODS

The records of 154 consecutive patients with SDAVFs were retrospectively reviewed.

RESULTS

There were 120 males and 34 females (male/female ratio 3.5:1, mean age 63.6 years). The SDAVFs were located at the thoracic level in 92 patients and at the lumbar and sacral spine levels in 45 and 15 patients, respectively. The most common presenting symptoms were motor dysfunction (65 patients), sensory loss (31 patients), and paresthesias without sensory loss (13 patients). The mean interval from symptom onset to definitive diagnosis was 24.7 months (median 12 months). Surgery resulted in complete exclusion of the fistula at first attempt in 146 patients (95%). There were no deaths or major neurological complications related to the surgery. Six percent of patients experienced subjective or objective worsening of preoperative symptoms and signs by the time of discharge that persisted at follow-up. Other surgical complications consisted of wound infection in 2 patients and deep venous thrombosis in 3. Eight patients were lost to follow-up; 141 patients (96.6%) experienced improvement (120 patients, 82.2%) or stability (21 patients, 14.4%) of motor function at last follow-up compared with their preoperative status. Other symptoms such as numbness, sphincter dysfunction, and dysesthesias/neuropathic pain improved in 51.5%, 45%, and 32.6%, respectively.

CONCLUSION

Surgical obliteration of SDAVFs is safe and very effective. Prognosis of motor function is favorable after surgical treatment.

Clinical Problem-Solving: Aneurysm or Spinal Arteriovenous Fistula—Bait and Switch

OBJECTIVE:

The authors use an instructive case to review the challenges of diagnosis in subarachnoid hemorrhage (SAH) and to reinforce the nuances of clinical management.

IMPORTANCE:

The presented case highlights critical issues in patient selection and challenges in the diagnosis of SAH and the management of both aneurysmal and arteriovenous fistula-related SAH. The critical points in decision making and diagnosis are discussed, and the case is accompanied by a brief review of the literature on the issues being faced.

CLINICAL PRESENTATION:

The present case is a patient presenting with SAH who was found to have an anterior communicating artery aneurysm. However, clues in the presentation and workup point to another etiology.

CONCLUSION:

A strong history of sudden neck pain before headache and abundance of SAH along the brainstem mandates a need to thoroughly evaluate the source of hemorrhage from cervical vessels through an angiogram.

Cervical spine dural arteriovenous fistula presenting with congestive myelopathy of the conus

Spinal dural arteriovenous fistulas (DAVFs) are the spinal vascular malformations that are encountered most often, and they are usually encountered in the lower thoracic region. Cervical spine DAVFs are exceedingly rare and may be difficult to differentiate from radicular arteriovenous malformations, epidural arteriovenous shunts, or perimedullary AVFs. Typical angiographic findings in spinal DAVFs include a slow-flow shunt with converging feeding vessels from radiculomeningeal arteries draining via a radicular vein centripetally into perimedullary veins. The MR imaging findings such as spinal cord edema and perimedullary dilated vessels may be used to direct the spinal angiography that is needed to localize and classify the shunt. When the shunt is distant from the pathological imaging findings, the diagnosis may be difficult to establish, especially when the shunt is present at an atypical location such as the cervical spine. The authors present the case of a 51-year-old man presenting with lower thoracic and conus medullaris congestive edema due to a cervical spine DAVF that was located at the C-5 level. Transarterial embolization with N-butyl cyanoacrylate closed the proximal vein and completely obliterated the fistula. Clinical and imaging follow-up confirmed occlusion of the fistula, with improvement in clinical symptoms.