Spinal Dural Arteriovenous Fistula Research Articles

A rare case of spinal dural arteriovenous fistula in a 22-year-old farmer

A rare case of spinal dural arteriovenous fistula in a 22-year-old farmer

Brainstem hemorrhage associated with venous hypertensive myelopathy without dural arteriovenous fistula: illustrative case.

Venous hypertensive myelopathy (VHM), formerly known as "Foix-Alajouanine syndrome," is a spinal cord dysfunction caused by impaired perfusion of the spinal cord. Most cases are attributed to spinal dural arteriovenous fistulas (dAVFs), but there are scattered reports of VHM without concomitant dAVF. Furthermore, no cases of VHM associated with intracranial hemorrhage exist. A 68-year-old man with a history of hypertension presented with a sudden headache, proximal paresis of the left upper extremity, impaired pain and temperature sensation in the right upper extremity, dysphagia, and dysarthria. Computed tomography scans showed intraparenchymal hemorrhage in the left medulla oblongata and a linear, continuous high-density area extending from the medulla oblongata to the cervical spinal cord. Magnetic resonance images showed cervical spondylosis at the C5-6 and C6-7 levels, with high signal intensity changes from the medulla oblongata to the lower cervical cord on T2-weighted images. Cerebral angiography showed no abnormal vessels. Conservative treatment gradually improved symptoms and the high signal intensity areas. This case highlights intracranial hemorrhage occurring from extracranial causes and the possibility of VHM due to cervical spondylosis. When hemorrhagic lesions of the craniovertebral junction or spinal parenchymal lesions are encountered, the underlying pathology should be investigated thoroughly and systematically. https://thejns.org/doi/10.3171/CASE24441.

Magnetic resonance imaging changes in spinal arteriovenous fistulae treated by endovascular means: are they reliable to predict complete cure of the fistula?

Regression or disappearance of MRI abnormalities is usually observed after treatment of spinal dural arteriovenous fistulae (sDAVF). To assess the correlation between spinal MRI (sMRI) changes with sDAVF exclusion and clinical outcome. Imaging data of patients treated with endovascular embolization for sDAVF between 2007 and 2023 were retrospectively analyzed. Spinal cord edema and perimedullary flow voids at baseline and 3-months' follow-up were compared between patients with and without sDAVF persistent occlusion and clinical improvement on the Aminoff and Logue Scale. Twenty-five patients were included in this study. At 3-months' follow-up, regression of spinal cord edema was significantly associated with sDAVF persistent occlusion (P=0.038). The combination of edema and flow voids regression was significantly associated with higher odds of a cured sDAVF (P<0.001) and clinical improvement (P<0.01). Improvement in the combination of the above-mentioned sMRI signs presented high sensitivity (100% (95% CI 78.20%-100%)) and negative predictive value (100% (95% CI 47.82%-100%)) for the detection of sDAVF cure compared with the criterion standard (digital subtraction angiography (DSA)). Patients with both spinal cord edema and flow voids regression at 3 months were more likely to present with a persistent occlusion of sDAVF and clinical improvement after endovascular embolization. Patients without sMRI improvement should be referred for DSA to seek recurrence of sDAVF.

Angiographically occult spinal dural arteriovenous fistula diagnosed by exploratory surgery with intraoperative ultrasound: illustrative case.

A 78-year-old male presented with progressive myelopathic symptoms. The clinical course and imaging findings raised a high suspicion for venous hypertensive myelopathy due to a spinal dural arteriovenous fistula (SDAVF). Magnetic resonance angiography and four complete spinal angiograms did not reveal the presence of an SDAVF. Despite multiple negative angiograms, intraoperative ultrasound revealed abnormal cord edema and arterialized pulsatile vessels, confirming the presence of an SDAVF. The fistula was found and cauterized, which resulted in a decrease in the caliber of the dilated veins and an observed reduction of spinal cord stiffness posttreatment. The patient exhibited gradual improvement in neurological function. Retrospective analysis of the multiple complete spinal angiograms failed to reveal an anomaly at the treated level or any other level. This case underscores the diagnostic utility of intraoperative Doppler ultrasound and the importance of maintaining a high index of suspicion for SDAVF in cases with consistent clinical characteristics and a lack of alternative diagnoses, even with negative spinal angiography. https://thejns.org/doi/10.3171/CASE24438.

Comparative microanatomy and histology of spinal and cerebral veins: Implications for dural arteriovenous fistula clinical presentations

Cranial dural arteriovenous fistulas (DAVFs) that display cortical venous drainage are at risk of hemorrhage, unlike spinal DAVFs, which seldom bleed. The underlying mechanism for this difference is poorly understood. We hypothesized that cerebral veins are more fragile than spinal veins due to differences in histologic compositions. Thus, spinal and cerebral veins from five formalin-fixed human cadavers were examined through macroscopic and histological analysis, using hematoxylin, eosin and safran (HES), and orcein stains to compare them. Twenty-four cerebral veins and thirteen spinal veins were analyzed. The mean diameter of the cerebral veins was 1.02 ± 0.59 mm, while that of spinal veins was 0.52 ± 0.26 mm (p = 0.003). The mean thickness of cerebral veins was similar to their spinal counterparts (0.09 ± 0.07 mm vs 0.06 ± 0.02 mm; p = 0.12). The mean diameter-to-thickness ratio was 13.76 ± 6.05 mm for cerebral veins and 10.06 ± 7.23 mm for spinal veins (p = 0.023). In most of the analyzed vessels, the venous wall was composed of endothelial cells resting on layers of smooth muscle, separated by elastica lamina. Cerebral and spinal veins exhibit distinct calibers while maintaining comparable wall thicknesses, resulting in a greater diameter-to-thickness ratio for cerebral veins compared to spinal veins. This difference may after their resistance to pressure. Furthermore, variations in the transparietal pressure gradient between cranial and spinal subarachnoid space, along with differences in arterial blood flow through the fistulous veins, might contribute to the observed differences in clinical presentation.

Comparison of nBCA and Onyx for Embolization of Spinal Dural Arteriovenous Fistulas

Background Endovascular embolization can effectively treat spinal dural arteriovenous fistulas (SDAVFs). One factor limiting the success and durability of endovascular treatments is reliably casting and occluding the draining vein. We sought to compare the efficacies of n ‐butyl‐2‐cyanoacrylate (nBCA) and Onyx in the treatment of SDAVFs. Methods We retrospectively analyzed patients with SDAVFs treated with endovascular embolization for whether a “durable cure” was achieved, defined as complete obliteration, clinical improvement, and sustained radiologic cure on follow‐up. We compared the outcomes of patients treated with Onyx to those treated with nBCA. Results A total of 40 embolizations for SDAVFs were performed in 38 patients. All patients were treated exclusively with liquid embolysates: Onyx alone (n = 22), nBCA alone (n = 16), or nBCA and Onyx combined (n = 2). For 45% (10/22) of patients treated with Onyx only, complete obliteration of the fistula with casting of the vein was not achieved. These patients were referred for microsurgical ligation. For all 16 patients treated with nBCA only, complete obliteration of the fistula was achieved. All 16 patients exhibited a durable cure compared with 11 of 22 patients (50%) in the Onyx‐only group ( P = 0.002). Conclusion nBCA may be superior to Onyx for the embolization of SDAVFs. nBCA embolization is safe and effective for a subset of SDAVFs. Prospective studies comparing SDAVF treatment strategies are warranted.

Spinal Dural Arteriovenous Fistula, a Rare and Frequently Misdiagnosed Cause of Mielopathy – Case Report and Review of the Literature

AbstractSpinal dural arteriovenous fistulas (SDAVFs) are rare vascular malformations with unspecific clinical manifestations, which often lead to misdiagnosis and delay in the establishment of effective therapies. Since the neurological prognosis depends on symptom duration and pretreatment neurological status, rapid identification and obliteration of the fistula are key to provide patients with a better quality of life. We herein describe an illustrative case of an elderly patient presenting with progressive myelopathy, with a definitive diagnosis of SDAVF after 18 months of the initial symptoms. We also review the core concepts regarding this condition and discuss strategies to prevent misdiagnosis and worsening of the neurological outcome.

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

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

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

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

Specific electromyography characteristics can distinguish longitudinally extensive transverse myelitis from congestive myelopathy due to spinal dural arteriovenous fistula: a retrospective study

Specific electromyography characteristics can distinguish longitudinally extensive transverse myelitis from congestive myelopathy due to spinal dural arteriovenous fistula: a retrospective study

Spinal dural arteriovenous fistula: a case-based review

Spinal dural arteriovenous fistula is an abnormal connection between radicular arteries and spinal venous plexus. This condition is relatively rare with annual incidence of five-ten cases per million. We present a case of a 62-year-old male with complaints of tingling in feet since six months and weakness in legs since 1 hour. Lower limb weakness progressed over a day to complete paralysis and bladder incontinence. Magnetic resonance imaging (MRI) spine showed a dural hypointensity over D6-D11 with abnormal vessels around spinal cord. Patient underwent spinal angiography which showed an intramedullary arteriovenous malformation causing compression. Arterial embolization was done within 24 hours from symptom onset and he ambulated within a week. AV malformations are a rare cause of compressive myelopathy presenting with acute paraplegia. Advances in endovascular techniques have made it possible to treat them early and prevent irreversible damage.

Case Report: Percutaneous intercostal artery catheterization to treat a difficult-to-access spinal dural arteriovenous fistula

Spinal dural arteriovenous fistulas (SDAVF) are a subtype of spinal arteriovenous malformation (AVM). Although rare, SDAVF are the most common spinal vascular malformations and have potential devastating neurologic consequences, sometimes irreversible. Originally, they were treated with surgery alone, however endovascular treatment of SDAVF has evolved recently with good results and the understanding of the anatomy plays a key role. The feeder vessel of the AV shunt is supplied by the radiculomedullary or radiculopial artery, the shunt is usually located within the root sleeve of the dura and the SDAVF is drained by the medullary vein via retrograde flow. Generally the endovascular approach uses the catheterization of the segmental arteries; however, aortic thoracolumbar aneurysms can render endovascular access difficult and risky. We present a case where an SDAVF in woman with aneurysmal dilation of the descending aorta and a mural thrombus was successfully treated through percutaneous catheterization of intercostal artery.

Spinal Dural Arteriovenous Fistulas: Surgical Outcome Analysis of Twenty Cases

Background: Spinal dural arteriovenous fistulas (SDAVFs) are rare complex spinal vascular shunts, which caninevitably lead to severe disability if remain untreated. Methods: Retrospective analysis of SDAVFs patientsina period of three years (2019 to 2021) who presented with progressive paraparesis, bladder symptoms and/or sensory disturbances. They were evaluated by MRI and localization of the fistula was done by spinal catheter angiogram. Spinal AV fistulas were simply classified as extradural and intradural.They all underwent microsurgical shunt interruption. Neurological function was evaluated by Aminoff-Logue Scale (ALS) consecutively at the day before surgery, 6 months and 1year after surgery. Results: A total of 20 patients (mean age 35 ± 10 years, 16 (80.0%) are male.The mean interval from onset to diagnosis was 6 ± 3 months. Among the anatomical location of fistulas, 1(05.0%) was in cervical, 16 (80.0%)were inthoracic, and 3 (15.0%) were in lumbar. Among the angiographic types of fistulas, 18(90.0%) were intradural and,2(10.0%) were extradural.Mean pre-treatment ALS was 5.3 and mean last examination ALS was 3.9. There was a significant improvement of the ALS between pretreatment and last examination ALS (P = 0.0009). Among 20 surgical procedures there were complications in three cases (15%): epidural hematoma in 1 case, cerebrospinal fluid leakage in 1 case and post-operative wound infection in 1 case Conclusions: In our study,microsurgical interruption of timely diagnosed SDAVF showed good and stable results over time. Bang. J Neurosurgery 2023; 12(2): 137-141

Preoperative Angiographic Protocol for the Surgical Management of Spinal Dural Arteriovenous Fistulas: A Technical Nuance for Safe Minimally Invasive Surgery

BackgroundInterruption of the fistoulus point is the goal of the treatment of spinal dural arteriovenous fistula (dAVFs). Microsurgery still represents a highly efficient treatment in terms of complete occlusion with the lowest risk of recurrence rate. It is reported that the hardest step consists in finding the fistulous site itself, potentially extending surgical access and time, and increasing potential post-operative surgical-related complications. The accurate preoperative detection of the shunt and spinal level together is crucial for guiding optimal, fast and safe microsurgical treatment. MethodsIn the present paper, the authors describe a preoperative angiographic protocol for achieving a safe and simple resection of spinal dAVFs based on a six-year Institutional experience of forty-two patients who underwent minimally invasive. Two illustrative cases are also included in order to support the technical descriptions. ResultsThe suspected artery associated to the vascular malformation of interest is studied in our angiographic protocol through non-subtracted selective acquisitions in the lateral projection. The resulting frames are reconstructed with 3D Rotational Angiography. The implementation of the preoperative angiographic protocol allowed 100% of intraoperative identification of the fistoulus point in all cases with the use of minimally invasive approach. ConclusionsNowadays, neurosurgeons advocate for minimally invasive procedures and low morbidity risk procedures for the treatment of spinal dAVFs.Our preoperative approach for accurate angigoraphic localization of the fistoulus point through non-subtracted and 3D reconstructed angiography allowed to achieve safe and definitive occlusion of the shunt.

A Novel Rat Model of Venous Hypertensive Myelopathy Produced by Arteriovenous Bypass Plus Venous Stenosis.

Venous hypertensive myelopathy (VHM), mainly induced by the spinal dural arteriovenous fistula, is a congestive spinal cord injury that currently has no appropriate animal model available in preclinical research. Sprague Dawley rats (280-320 g) were used. The rats were divided into 3 groups: (1) Group 1, which underwent renal artery-dorsal spinal venous bypass (AVB group); (2) Group 2, which underwent renal artery-dorsal spinal venous bypass and drainage vein stenosis (AVB/VS group); and (3) Control group, with T13 dorsal vein ligation. The success of the model was assessed using Doppler ultrasound and 7.0-T magnetic resonance imaging. Transmission electron microscopy, histochemistry, proteomics, and western blot analysis were used to evaluate ultrastructural, pathological, and molecular features in the spinal cord and cerebrospinal fluid (CSF). The success rate of the arteriovenous bypass was 100% at 5 days and 83% at 2 weeks. The locomotor assessment showed decreased lower extremity strength in the AVB/VS group ( P = .0067), whereas unremarkable changes were found in the AVB and Control groups. Histochemical staining suggested a 2-fold expansion of the dorsal spinal vein in the AVB/VS group, which was lower than that in the AVB group ( P < .05); however, the former displayed greater myelin and neuronal damage ( P < .05) and slight dilatation of the central canal ( P > .05). Proteomics analysis revealed that the complement and coagulation cascade pathways were upregulated in the CSF of AVB/VS rats, whereas the C3 level was elevated both in the CSF and bilateral spinal cord. Furthermore, overexpression of C3, ITGB2, and CD9 in the spinal cord was confirmed by immunoblotting. These findings suggest that the AVB/VS model can effectively mimic the clinical and molecular characteristics of VHM. Furthermore, they suggest that impaired deep intramedullary venous drainage is the key reason for the VHM.

The Impact of Magnetic Resonance Imaging Findings in Predicting Neurological Status Pre- and Post-Treatment of Spinal Dural Arteriovenous Fistulas: A 22-Year Experience in a Neurovascular and Spine Center.

Successful treatment of spinal dural arteriovenous fistulas (SDAVF) requires prompt diagnosis with definitive fistula localization and non-delayed treatment. Magnetic resonance imaging (MRI) is used for the screening and follow-up of SDAVF, although the value of MRI signs such as myelopathy and flow voids is controversial. Therefore, we investigated the predictive value of MRI signs pre- and post-treatment and their correlation with the neurological status of SDAVF patients. We retrospectively analyzed the clinical records of 81 patients who underwent surgical or endovascular treatment for SDAVF at our hospital between 2002 and 2023. A total of 41 SDAVF patients with follow-up MRI of 4.6 [2.9-6.5] months (median [interquartile range]) post-treatment and clinical follow-up of 3, 6, and 12 months were included. The extent of pretreatment myelopathy was seven [6-8] vertebral levels, with follow-up MRI showing no myelopathy in 70.7% of cases. The pretreatment flow voids extended over seven [4.5-10] vertebral levels and completely disappeared on follow-up MRI in 100% of cases. The modified Aminoff-Logue scale of disability (mALS) was four [2-7] pretreatment and two [0-4.5] at the third follow-up, with improvement in 65.9% of patients. The American Spinal Injury Association motor score (ASIA-MS) was 97 [88-100] pretreatment and 100 [95-100] at the third follow-up assessment, with 78% of patients improving. Pretreatment ASIA-MS correlated with the extent of myelopathy at admission (R2: 0.179; 95% CI: -0.185, -0.033; p = 0.006) but not with flow voids at admission, while pretreatment mALS showed no correlation with either MRI signs. The improvement in ASIA-MS and mALS between admission and the last follow-up showed no correlation with the extent of pretreatment myelopathy and flow voids or with pos-treatment MRI changes. The diagnostic sensitivity of magnetic resonance angiography (MRA) for localization of the fistula was 68.3% (28/41). The severity of the clinical condition in SDAVF patients has a multifactorial cause, whereby the ASIA-MS correlates with the extent of myelopathy pretreatment. MRI changes after treatment showed no correlation with the clinical outcome and cannot be used as a prognostic factor.

Diagnostic, clinical management, and outcomes in patients with spinal dural arteriovenous fistula.

Spinal dural arteriovenous fistulas (SDAVFs) are rare spinal vascular malformations, but account for 70 to 80% of all spinal arteriovenous malformations. SDAVFs can be treated either surgically or endovascularly, with surgical treatment appearing to lead to higher closure rates. Our aim was to analyze the demographic data, diagnostic history, treatment characteristics and clinical short- and long-term outcomes. The medical records of 81 patients who underwent surgical (n = 70, 86.4%) and endovascular (n = 11, 13.6%) treatment for SDAVF at a university hospital between 2002 and 2023 were retrospectively analyzed. SDAVF was observed more frequently in men than women (61, 75.3% vs. 20, 24.7%) with a mean age of 63.5 ± 12.7 years and a mean duration of symptoms to diagnosis of 12.0 ± 12.8 months. The most common first symptom was gait disturbance (36, 44.4%), followed by sensory disturbance (24, 29.6%). The location of the fistula point was most common in the lower thoracic region (36, 44.5%), followed by the lumbar region (23, 28.4%). Incomplete or failed occlusion of the fistula occurred in 8 patients (9.9%), with 6 patients (7.4%) undergoing further treatment either surgically or endovascularly. Treatment- or hospital-related complications were observed in 16 patients (19.8%). A single-level laminectomy was the most common approach (31, 44.3%), followed by single-level hemilaminectomy (28, 40.0%), and unilateral interlaminar fenestration (11, 15.7%). Back pain or radiculopathy was observed in 58% of patients (47/81) pre-treatment and had already decreased to 24.7% at hospital discharge (p < 0.001). No significant differences were observed in sensory disturbances (p = 0.681). The median of American Spinal Injury Association motor score (ASIA-MS) was 94 [82.5-100] at admission, 98 [86.5-100] at hospital discharge, 100 [90-100] at the first, second, and third follow-up (p = 0.019). The median modified Aminoff-Logue scale (mALS) was 5 [2-7] at admission, 3 [1-6] at hospital discharge, 2 [1-5] at the first follow-up, 2 [0.5-5] at the second follow-up and 2 [1-7] at the third follow-up (p = 0.006). SDAVF occurs predominantly in men in the 6th decade of life and can be safely and effectively treated surgically and endovascularly, improving symptoms such as pain and motor deficits, gait disturbances as well as bowel and bladder dysfunction, but not sensory disturbances.

Histopathological analysis of the wall enhancement of the spinal dural arteriovenous fistulae's draining veins.

The mechanism behind SDAVF is still unclear. We discovered that the vessel wall of the SDAVF-DV occasionally showed enhancement in MRI, and this study assessed the relationship between the enhancement of the draining vein's wall and its histology. For histopathologic analysis, 16 draining vein samples from 16 patients with SDAVF were included, 3 normal arteries and 3 normal veins were chosen as comparison. We assessed the imaging and microscopic characteristics of the draining veins in SDAVF patients. The former included the presence of significant enhancement of the wall of the draining vein in MRI, and the latter included the adherence, aggregation, infiltration of pro-inflammatory factors and inflammatory cells. Immuno-histochemical staining was performed using IL-1β, IL-8, TGF-β as well as MPO and MMP-9, and positive results were counted. Multiple logistic regression analysis was used to determine whether the infiltration of inflammatory cells was connected to vessel wall enhancement in the SDAVF-DV. Infiltration of inflammatory cells was significantly higher in SDAVF-DV compared to normal vessels, 7 out of 16 patients significantly had enhancement of the vessel wall of SDAVF-DV, and logistic regression analysis showed that samples with more infiltration of inflammatory cells were more likely to show enhancement of the SDAVF-DV walls. There was considerable inflammatory cells infiltration in SDAVF-DV, and this may explain why their vessel wall had such a significant enhancement in MRI.

Evaluating the diagnostic accuracy of 3D contrast-enhanced magnetic resonance angiography versus digital subtraction angiography in spinal dural arteriovenous fistulas.

Spinal dural arteriovenous fistulas (SDAVFs) often go undiagnosed, leading to irreversible spinal cord dysfunction. Although digital subtraction angiography (DSA) is the gold standard for diagnosing SDAVF, DSA is invasive and operator dependent, with associated risks. MR angiography (MRA) is a promising alternative. This study aimed to evaluate the performance of MRA as an equal alternative to DSA in investigating, diagnosing, and localizing SDAVF. Prospectively collected data from a single neurosurgeon at a large tertiary academic center were searched for SDAVFs. Eligibility criteria included any patient with a surgically proven SDAVF in whom preoperative DSA, MRA, or both had been obtained. The eligible patients formed a consecutive series, in which they were divided into DSA and MRA groups. DSA and MRA were the index tests that were compared to the surgical SDAVF outcome, which was the reference standard. Accurate diagnosis was considered to have occurred when the imaging report matched the operative diagnosis to the correct spinal level. Comparisons used a two-sample t-test for continuous variables and Fisher-Freeman-Halton's exact test for categorical variables, with p < 0.05 specifying significance. Univariate, bivariate, and multivariate analyses were conducted to investigate group associations with DSA and MRA accuracy. Positive predictive value, sensitivity, and accuracy were calculated. A total of 27 patients with a mean age of 63 years underwent surgery for SDAVF. There were 19 male (70.4%) and 8 female (29.6%) patients, and the mean duration of symptoms at the time of surgery was 14 months (range 2-48 months). Seventeen patients (63%) presented with bowel or bladder incontinence. Bivariate analysis of the DSA and MRA groups further revealed no significant relationships between the characteristics and accuracy of SDAVF diagnosis. MRA was found to be more sensitive and accurate (100% and 73.3%) than DSA (85.7% and 69.2%), with a subanalysis of the patients with both preoperative MRA and DSA showing that MRA had a greater positive predictive value (78.6 vs 72.7), sensitivity (100 vs 72.7), and accuracy (78.6 vs 57.1) than DSA. In surgically proven cases of SDAVFs, the authors determined that MRA was more accurate than DSA for SDAVF diagnosis and localization to the corresponding vertebral level. Incomplete catheterization at each vertebral level may result in the failure of DSA to detect SDAVF.

The negative impact of treatment delays on the long-term neurological outcomes of spinal dural arteriovenous fistulas: a longitudinal cohort study.

Dural arteriovenous fistulas are rare vascular malformations that affect the brain and spinal cord. Spinal dural arteriovenous fistulas (sdAVFs) are the most frequently encountered vascular malformation affecting the spinal cord. The object of this study was to evaluate the impact of treatment delays on the long-term neurological outcomes of either open surgical or interventional treatment of sdAVFs. In this retrospective, population-based cohort study, the authors examined consecutive patients with diagnosed sdAVFs at a tertiary care center between 2005 and 2020. Patients were assessed using the Aminoff-Logue disability scale (ALS) at various time points including symptom onset, primary care visit, first specialist outpatient visit, as well as both short and long-term follow-ups. The postoperative long-term ALS gait and bladder grades constituted the primary outcomes of the study. Among the 34 patients included in the study, the median age was 65 years, and there was a male predominance (71%). Most lesions were in the lumbar region (47%). Significant worsening in ALS gait and bladder grades was observed preoperatively, followed by postoperative improvements (p < 0.05). There was no difference in outcomes between surgical and endovascular treatments. Older age (OR 1.10, 95% CI 1.03-1.17, p = 0.007), worse preoperative ALS gait grades (OR 5.12, 95% CI 2.18-12.4, p < 0.001), and longer time from first specialist outpatient visit to first treatment (OR 1.00, 95% CI 1.00-1.01, p = 0.040) were independently associated with worse long-term gait outcomes. Only the preoperative ALS bladder score was a predictor of worse long-term bladder function (OR 92.7, 95% CI 28.0-306.7, p < 0.001). Both surgical and endovascular treatments for sdAVFs led to significant neurological improvements. However, treatment delays were associated with less favorable long-term outcomes. Prompt diagnosis and early intervention prior to symptom progression may enhance recovery and help to preserve neurological function.