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

Multiple Synchronous Spinal Dural Arteriovenous Fistulas: A Systematic Literature Review

BACKGROUND AND OBJECTIVES

Spinal dural arteriovenous fistulas (SDAVFs) lead to progressive neurological decline with symptoms such as paraparesis, bowel and bladder dysfunction, and sensory disturbances because of impaired spinal cord venous drainage. This study aimed to systematically review the literature on multiple synchronous SDAVFs and present 2 cases from our institution.

METHODS

A comprehensive search was performed to identify all published cases of multiple synchronous SDAVFs. Overall, 23 patients with multiple synchronous SDAVFs were identified, including 21 from 19 articles and 2 from this study. The clinical presentation, lesion location, radiographic features, surgical treatment, and outcomes were analyzed in each patient.

RESULTS

All patients in this study were male, and the duration from symptom onset to diagnosis in many of these patients was longer than that previously reported. Previous studies suggested that multiple SDAVFs typically occurred within 3 or fewer vertebral levels. However, >50% of the examined patients had remote lesions separated by more than 3 vertebral levels. Patients with remote lesions had a significantly worse outcome (1/7 vs 8/11, 95% CI 0.001-0.998; P = .049).

CONCLUSION

Accurately locating fistulas before spinal angiography is critical for managing multiple remote SDAVFs. Considering the possibility of multiple remote SDAVFs, careful interpretation of imaging findings is essential for an accurate diagnosis and appropriate treatment planning.

Risk factors for postoperative late deterioration in patients with spinal dural arteriovenous fistulas

Background

Approximately 86% of patients with spinal dural arteriovenous fistulas (SDVAFs) exhibit clinical improvement after surgery. However, 12%-55.8% of these patients experience late deterioration (LD) after an initial period of improvement. The risk factors for LD remain unclear. The aim of this study was to explore the risk factors for LD in SDVAF patients.

Methods

The clinical data of patients who were admitted to two tertiary hospitals between June 2014 and May 2022 were reviewed. Patients were divided into two groups: the LD group and the no LD group. The severity of neurological dysfunction (NDF) was evaluated using the Modified Aminoff and Logue Scale. Univariable and multivariable Cox regression analyses were performed.

Results

A total of 105 eligible patients were enrolled, with a mean age of 57.55 ± 9.42 years. The LD group comprised 37 individuals, while the no LD group consisted of 68 individuals. According to the univariable analysis, preoperative NDF severity and treatment strategy were associated with the risk of LD. According to the multivariable analysis, patients who underwent microsurgery (MS) had a lower risk of LD than did those who underwent endovascular treatment (EVT; HR 0.197, 95% CI 0.085-0.457), and patients with severe NDF had a higher risk of LD than did those with mild NDF (HR 3.604, 95% CI 1.226-10.588), whereas the risk of LD in patients with moderate NDF was similar to that of patients with mild NDF (HR 1.352, 95% CI 0.519-3.524).

Conclusion

EVT and severe preoperative NDF are independent risk factors for LD.

Application of Spinal Subtraction and Bone Background Fusion CTA in the Accurate Diagnosis and Evaluation of Spinal Vascular Malformations

BACKGROUND AND PURPOSE

Accurate pretreatment diagnosis and assessment of spinal vascular malformations using spinal CTA are crucial for patient prognosis, but the postprocessing reconstruction may not be able to fully depict the lesions due to the complexity inherent in spinal anatomy. Our purpose was to explore the application value of the spinal subtraction and bone background fusion CTA (SSBBF-CTA) technique in precisely depicting and localizing spinal vascular malformation lesions.

MATERIALS AND METHODS

In this retrospective study, patients (between November 2017 and November 2022) with symptoms similar to those of spinal vascular malformations were divided into diseased (group A) and nondiseased (group B) groups. All patients underwent spinal CTA using Siemens dual-source CT. Multiplanar reconstruction; routine bone subtraction, and SSBBF-CTA images were obtained using the snygo.via and ADW4.6 postprocessing reconstruction workstations. Multiple observers researched the following 3 aspects: 1) preliminary screening capability using original images with multiplanar reconstruction CTA, 2) the accuracy and stability of the SSBBF-CTA postprocessing technique, and 3) diagnostic evaluation of spinal vascular malformations using the 3 types of postprocessing images. Diagnostic performance was analyzed using receiver operating characteristic analysis, while reader or image differences were analyzed using the Wilcoxon signed-rank test or the Kruskal-Wallis rank sum test.

RESULTS

Forty-nine patients (groups A and B: 22 and 27 patients; mean ages, 44.0 [SD, 14.3] years and 44.6 [SD,15.2] years; 13 and 16 men) were evaluated. Junior physicians showed lower diagnostic accuracy and sensitivity using multiplanar reconstruction CTA (85.7% and 77.3%) than senior physicians (93.9% and 90.9%, 98% and 95.5%). Short-term trained juniors achieved SSBBF-CTA image accuracy similar to that of experienced physicians (P > .05). In terms of the visualization and localization of spinal vascular malformation lesions (nidus/fistula, feeding artery, and drainage vein), both multiplanar reconstruction and SSBBF-CTA outperformed routine bone subtraction CTA (P = .000). Compared with multiplanar reconstruction, SSBBF-CTA allowed less experienced physicians to achieve superior diagnostic capabilities (comparable with those of experienced radiologists) more rapidly (P < .05).

CONCLUSIONS

The SSBBF-CTA technique exhibited excellent reproducibility and enabled accurate pretreatment diagnosis and assessment of spinal vascular malformations with high diagnostic efficiency, particularly for junior radiologists.

Delayed Diagnosis of Spinal Dural Arteriovenous Fistula: A Case Report and Scoping Review

Spinal dural arteriovenous fistula (SDAVF) is among the most common arterial shunt diseases typically found in middle aged or older men. Herein, we aimed to clarify the reasons for misdiagnoses and delayed diagnoses of SDAVF, determine how these affect prognoses, and establish how they can be prevented. We conducted a PubMed/MEDLINE literature search using "spinal dural arteriovenous fistula", "delayed diagnosis", "late diagnosis", and "misdiagnosis" terms. We identified 18 articles, including 965 SDAVF cases. Patients were predominantly males (71.8-100.0%) (mean age: 53.5-71.0 years). Misdiagnoses rates varied (17.5-100.0%) and encompassed many conditions. The mean time between early manifestations and confirmed diagnosis was approximately 10-15 months and from the first radiologic image revealing dural arteriovenous fistula (DAVF) features to diagnosis was 9.2-20.7 months. Posttreatment outcomes showed a significant improvement in motor functions, gait, and micturition, particularly in patients exhibiting preoperative symptoms over a short period. SDAVF is frequently misdiagnosed or subject to delayed diagnosis, causing poor clinical outcomes. SDAVF symptoms including progressive lower-limb weakness, paresthesia, and vesicorectal dysfunction are indications for spinal magnetic resonance imaging with subsequent spinal angiography, wherein DAVF is evidenced by extensive T2 hyperintensity and flow-void abnormalities. We reported a representative case with delayed diagnosis.

Exploring Spinal Subarachnoid Hemorrhage: A Neurosurgical Case Series

Spinal subarachnoid hemorrhage (SSAH) is a rare condition that can cause spinal cord or nerve root compression and permanent neurologic damage. The reported etiologies include trauma, vascular malformations or aneurysms, coagulopathies, neoplasms, autoimmune disease, and spontaneous hemorrhage. If there is evidence of neurologic deterioration, it is commonly managed as a surgical emergency, but cases of conservative management have also been reported. In this case series, we present three patients who suffered from SSAH. The first was a spontaneous cervical SSAH that occurred following cardiac catheterization, the second was a spontaneous thoracolumbar SSAH in a patient with a known history of coagulopathy, and the third was a thoracolumbar SSAH that was caused by a dural arteriovenous fistula (dAVF). All three patients exhibited neurologic deficits and thus underwent emergent decompression and hematoma evacuation. The patient with the dAVF also required open ligation of the fistula. Following surgical intervention, all three patients regained at least partial neurologic function, but one patient developed symptomatic arachnoid cysts that required further intervention. The presented case series highlights the importance and time-sensitivity of surgical decompression in patients experiencing neurologic deficits from SSAH. These cases underscore the urgency of timely neurosurgical intervention to mitigate neurologic impairment and add insights to the existing literature on this rare condition.

MRI characteristics of lumbosacral dural arteriovenous fistulas

Background and purpose

Spinal dural arteriovenous fistulas located in the lumbosacral region are rare and present with nonspecific clinical signs. The purpose of this study was to find out the specific radiologic features of these fistulas.

Methods

We retrospectively reviewed the clinical and radiological data of 38 patients diagnosed with lumbosacral spinal dural arteriovenous fistulas in our institution from September 2016 to September 2021. All patients underwent time-resolved contrast-enhanced three-dimensional MRA and DSA examinations, and were treated with either endovascular or neurosurgical strategies.

Results

Most of the patients (89.5%) had motor or sensory disorders in both lower limbs as the first symptoms. On MRA, the dilated filum terminale vein or radicular vein was seen in 23/30 (76.7%) patients with lumbar spinal dural arteriovenous fistulas and 8/8 (100%) patients with sacral spinal dural arteriovenous fistulas. T2W intramedullary abnormally high signal intensity areas were found in all lumbosacral spinal dural arteriovenous fistula patients, with involvement of the conus present in 35/38 (92.1%) patients. The "missing piece sign" in the intramedullary enhancement area was seen in 29/38 (76.3%) patients.

Conclusion

Dilatation of the filum terminale vein or radicular vein is powerful evidence for diagnosis of lumbosacral spinal dural arteriovenous fistulas, especially for sacral spinal dural arteriovenous fistulas. T2W intramedullary hyperintensity in the thoracic spinal cord and conus, and the missing-piece sign could be indicative of lumbosacral spinal dural arteriovenous fistula.

Spinal dural arteriovenous fistula: A rare but treatable disease that should not be missed by orthopedic surgeons

Objective

Spinal dural arteriovenous fistula (SDAVF) is a rare disease that is often misdiagnosed by orthopedic surgeons. We analyzed the reasons for the misdiagnosis and proposed countermeasures.

Methods

Twenty-two SDAVF patients who were initially treated in orthopedics were included. The patients were divided into a correct diagnosis group (A) and a misdiagnosis group (B). The clinical data and prognosis were evaluated.

Results

There were 10 patients in group A and 12 patients in group B. The clinical manifestations included limb numbness, weakness, and bladder and bowel dysfunction. Among these patients without spinal degenerative diseases which had typical magnetic resonance imaging (MRI) features in Group A were more than Group B (P < 0.05). More patients had spinal degenerative diseases in group B. In group A, seven patients were primarily diagnosed with a SDAVF after multidisciplinary teamwork (MDT). In group B, five patients were misdiagnosed with lumbar spinal stenosis, four with lumbar disc herniation, two with thoracic spinal stenosis, and one with cervical spinal stenosis and lumbar spinal stenosis and underwent cervical spinal canal and lumbar spinal canal decompression. The length of time for confirming the diagnosis was 7 months longer in group B than in group A. All patients underwent microsurgery treatment. The average follow-up duration was 11 months. The modified Aminoff-Logue Disability Scale scores showed a statistically significant difference in improvement between the two groups (P < 0.05).

Conclusion

when patients with dysuria especially, have intermittent spinal nerve dysfunction, the possibility of SDAVF should be considered. Awareness of the specific clinical and spinal cord edema and flow voids on MRI of a SDAVF needs to be promoted for orthopedic surgeons. Timely MDT is an important measure for reducing misdiagnosis, and steroids or inappropriate surgery should be avoided until a SDAVF is completely excluded.

Long-term outcomes and prognostic factors in patients with treated spinal dural arteriovenous fistulas: a prospective cohort study

OBJECTIVE

To define the pattern of long-term clinical outcomes and prognostic factors in patients with spinal dural arteriovenous fistulas (SDAVFs).

DESGIN

Prospective cohort study based on constantly recruiting patients with SDAVFs in two medical centres in China.

SETTING

Patients with SDAVFs were recruited consecutively between March 2013 and December 2014 in two referral centres.

PARTICIPANTS

A prospective cohort of 94 patients with SDAVFs was included in this study, and 86 patients (mean age 53.0 years, 71 men) completed the study. Patients who had previously undergone endovascular or neurosurgical treatment or had neurological dysfunction caused by other diseases or refused treatment were excluded.

INTERVENTIONS

All patients underwent neurosurgery or endovascular embolisation. These patients were evaluated with the modified Aminoff and Logue's Scale (mALS) 1 day before and 3, 6, 12 and 72 months after treatments.

RESULTS

The duration of symptoms ranged from 0.5 to 66 months (average 12.8 months). The location of SDAVFs was as follows: 33.7% above T7, 50.0% between/include T7 and T12% and 16.3% below T12. 75 patients (87.2%) underwent neurosurgical treatment, and 9 patients (10.5%) underwent endovascular treatment. 58 patients (67.4%) exhibited an improvement in mALS of one point or greater at 72 months. Patients with less disability were more likely to improve at 72 months (p<0.05). 48 patients (55.8%) showed deterioration at 72 months compared with 12 months. 61% of the patients suffered numbness, and 22% had pain before treatment. However, 81% of patients had numbness, and 28% had pain after treatment. This deterioration was related to 1-year mALS and age.

CONCLUSION

Nearly two-thirds of the patients experienced clinical improvement at 72 months, and preoperative (1 day before treatment) mALS was the strongest predictor of clinical improvement. However, 55.8% of patients showed deterioration after temporary recovery. All patients with SDAVFs should accept treatment as soon as possible.

Clinical heterogeneity of low flow spinal arteriovenous fistulas; a case series

Background

Spinal AVF (SAVF), a potentially treatable cause of myelopathy, remains a challenging diagnosis. Its rarity and non-specific imaging findings often result in misdiagnosis despite a high index of clinical suspicion. The classically described high T2 signal in the spinal cord or prominent vascular flow voids in the intradural space were not infrequently missed on initial imaging, only to be picked up at follow-up imaging after progression of symptoms. Additionally, small sized fistulas(< 1 mm) and SAVF involving less frequent locations like the craniocervical junction in a patient presenting with paraplegia further complicates the diagnosis. On rare occasions, acute atypical presentation following a surgery adds to the conundrum. Definite diagnosis with spinal angiography, the gold-standard modality requires the expertise of highly skilled interventionists which may otherwise lead to false negative findings. We describe four SAVF patients with unconventional presentations, highlighting less described clinical findings.

Case presentation

First was a 50-year-old man presented with spastic paraparesis and was found to have an AVF at the cervical region arising from the vertebral artery. Second, a 45-year-old man with acute paraplegia post-operatively, initially treated for a transverse myelitis before lumbar region AVF was detected. Thirdly, a 27-year-old man presented with subacute lower thoracic myelopathy and deteriorated after corticosteroid treatment. The last patient, who initially appeared to have conus medullaris/cauda equina syndrome had a SAVF at the mid thoracic level. Presentation varied with some exhibiting acute deterioration mimicking other spinal cord pathology such as inflammatory disorders. All patients eventually underwent endovascular treatment with successful embolization of SDAVF. None of them exhibited further neurological deterioration after embolization.

Conclusion

Successful treatment of SAVF is possible provided the diagnosis is made early, allowing timely intervention. Certain clues may aid the diagnosis. Firstly, arteriovenous fistula can be located distant to the clinical localization of myelopathy resulting in the unexpected longitudinally extensive spinal cord signal change. This clinical-radiological discrepancy can be a useful clue in diagnosing SAVF. Secondly, an acute myelopathic presentation immediately post-surgery may be related to SAVF. Other SAVF feature of note includes progressive myelopathy mimicking immune-mediated myelitis among young adults below 30 years of age refractory to immune therapy.

Spinal dural arteriovenous fistulas: a report on outcomes in a single-center retrospective cohort treated surgically and/or endovascularly

AIM

To report on the outcomes of spinal dural arteriovenous fistulas (sDAVFs) treatment in a single-center retrospective cohort.

METHODS

Data were retrieved on sDAVF cases treated surgically and endovascularly between January 2009 and January 2020. Sociodemographic, clinical, imaging data, and outcomes were analyzed.

RESULTS

Thirty-four patients were identified: 11 female, mean age 64.1 ± 11.5 years; mean time of symptom duration 12 (range 1-149) months. The sDAVF locations were the following: 18 (62.1%) thoracic, 4 (13.8%) lumbar, 4 (13.8%) sacral, and 3 (10%) with multiple location feeders. All patients had a motor deficit and affected walking, and the majority had a sensory deficit, bowel, and bladder dysfunction. Fifteen (44.1%) patients underwent surgical treatment, 7 (20.6%) underwent endovascular treatment, and 12 (35.3%) underwent both (crossover). Radiological myelopathy showed regression in 19 (55.9%) patients. Overall, clinical improvement (decrease in modified Rankin score) following treatment was observed in 14 patients (41.2%), worsening in 1 (2.9%), while other had unchanged status. The proportion of patients with initial treatment failure markedly differed between the before-2014 and after-2014 period. Patients who failed to improve had more extensive myelopathy.

CONCLUSION

Patients who underwent surgery or endovascular treatment had on average significant clinical recovery, while those who underwent treatment crossover had negligible improvement. The extent of myelopathy seems to be associated with clinical improvement.

Spinal dural arteriovenous fistula 8 years after lumbar discectomy surgery: A case report and review of literature

BACKGROUND

Spinal dural arteriovenous fistula (SDAVF) is an extremely rare vascular malformation of the central nervous system that is often confused with degenerative spinal disorders due to similar early symptoms and clinical features. Here, we report a case of SDAVF recurrence 8 years after lumbar spine surgery and summarize relevant literature.

CASE SUMMARY

A 54-year-old male was admitted to our hospital complaining of lower back pain, numbness in both lower extremities and intermittent claudication. Subsequent imaging identified lumbar spinal stenosis. Following surgical treatment, the patient’s symptoms significantly resolved, and he was able to perform daily activities. However, similar symptoms appeared 8 years later, followed by confirmation of SDAVF diagnosis. The patient underwent neurosurgery 7 mo after symptom onset. The follow-up period lasted 14 mo, and the patient remains with marginal neurological symptoms.

CONCLUSION

This case highlights the importance of prompt SDAVF diagnosis. Due to its nonspecific clinical presentation, the clinical experience of the surgeon and definitive imaging examination are indispensable. Additionally, timely neurosurgery is effective and may significantly improve patient outcomes.

Incidental Finding of a Duplicated Vertebral Artery Followed by a Spinal Dural Arteriovenous Fistula on Spinal Angiography

Duplicated origin of the vertebral artery (VA) is an extremely rare normal anatomic variant. While most often considered non-pathological, duplicated origin carries an increased risk of dissection. An association with vascular pathologies such as aneurysms, arteriovenous malformations, and AV fistulas has been suggested. The objective is to describe this unusual anatomic variant with is concomitant vascular pathology and review current literature. The authors report a case of incidentally-discovered duplicated origin of the left VA in patients with a spinal dural arteriovenous fistula (dAVF). A 61-year-old man with a history significant for sarcoidosis presented with progressive lower extremity weakness and paresthesias. MRI of the thoracic spine demonstrated significant confluent edema and patchy contrast enhancement in the caudal spinal cord and conus medullaris which did not appear related to the patient's neurosarcoidosis. A diagnostic spinal angiogram incidentally demonstrated that the left V1 segment had a duplicated origin, one branch arising from the aortic arch and the other branch arising from the left subclavian artery, with union at the C5 transverse foramen. This finding represented an incidental anomaly discovery was noted to be incidental and was not believed to be related to the patients underlying pathology. Subsequently, a dAVF was discovered, originating from the right T7 spinal artery. Location of this vascular malformation directly correlated with the patient’s symptoms. The patient then underwent embolization of the spinal dAVF and recovered uneventfully. Duplicated origin of the VA is an extremely rare but well-described variant, most commonly involving the left VA. To our knowledge, this is the only reported spinal dAVF associated with duplicated origin of the left VA. An association with other pathological entities has been suggested, and thus this case adds to a growing body of cases characterizing these relationships.