Bilateral cervical spinal dural arteriovenous fistulas with intracranial venous drainage mimicking a foramen magnum dural arteriovenous fistula

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.

Arteriovenous shunts of the cervical spine: patient demographics, presentation, patterns of high-risk venous drainage, and updated classification

BACKGROUND

Intracranial dural arteriovenous (AV) fistula classifications focus on presence/absence of retrograde flow in the cortical veins of the brain as this angiographic finding portends a worse prognosis. However, prior categorization systems of AV shunts in the spine do not incorporate these features. We propose an updated classification for spinal shunting lesions that terms any shunting lesion with retrograde flow in any cortical vein of the brain or spinal cord medullary vein as "high risk". To present this classification, we analyzed our center's most recent experience with cervical spine shunting lesions.

METHODS

The electronic medical record at our institution was reviewed to identify shunting lesions of the cervical spine and patient demographics/presentation. Comprehensive craniospinal digital subtraction angiograms were evaluated to classify shunt location, type (arteriovenous malformation (AVM) vs arteriovenous fistula (AVF)), and presence of high-risk venous drainage.

RESULTS

Some 52 lesions were identified and categorized as pial/dural/epidural/paravertebral AVFs and intramedullary/extraspinal AVMs. Lesions were classified as high risk or not depending on the presence of retrograde flow into at least one vein that directly drains the spinal cord or brain. All patients who presented with either hemorrhage or infarct had underlying high-risk lesions. Additionally, 50% (17/34) of symptomatic patients with high-risk lesions presented with neurological extremity symptoms (OR=10.0, p=0.037) most of which fit a myelopathic pattern.

CONCLUSION

We present an updated classification system for shunting lesions of the spine that focuses on high-risk retrograde flow to the brain or spine in addition to anatomical location in order to better inform patient management.

Case of Cowden Syndrome with 15 Spinal Arteriovenous Fistulas

BACKGROUND

Spinal vascular malformations are rarely multiple: fewer than 50 observations have been documented so far, with a maximum of 4 coexisting lesions per patient, always restricted to a single vertebral region (e.g., cervical or thoracic).

CASE DESCRIPTION

We describe the case of a 61-year-old woman with Cowden syndrome with 15 spinal arteriovenous fistulas (AVFs) at the cervical, thoracic, and lumbar levels and an adrenal AVF. She was initially referred for reevaluation of an upper cervical spinal epidural spinal arteriovenous fistula diagnosed 6 years earlier. Her history included breast carcinoma, a malignant salivary gland tumor, and removal of multiple ovarian, thyroid, and gastric hamartomas. Computed tomography and magnetic resonance imaging confirmed the presence of a prominent cervical vascular lesion. Spinal digital subtraction angiography revealed the presence of 15 additional vascular anomalies.

CONCLUSIONS

This multiplicity of AVFs appears to result from a combination of various factors including local regional hemodynamic changes, growth factor-mediated alterations involving notably vascular endothelial growth factor pathways, and the prothrombotic state associated with abnormalities in blood vessel structure.

Dural Arteriovenous Fistulas at the Craniocervical Junction: A Series Case Report

BACKGROUND

Craniocervical junction dural arteriovenous fistulas (CJDAVFs) are rare vascular malformations with unclear clinical characteristics. This study investigated the clinical characteristics and outcomes of patients with CJDAVFs.

METHODS

Thirty-eight patients with CJDAVFs who had undergone either conservative or surgical treatment were retrospectively analyzed.

RESULTS

Eleven (28.9%) patients were women and 27 (71.1%) were men (median age, 52.5 years). Two (5.3%) had myelopathy, and 36 (94.7%) had subarachnoid hemorrhage (SAH). Three patients had SAH recurrence before treatment. Five patients (13.9%) with SAH initially had negative results on angiography, which may have been due to a low-flow fistula without varicose veins (P = 0.034) and acute hydrocephalus (P = 0.084). Coincidental vascular lesions were noted in 5 patients (13.2%). Caudal drainage was mainly found in patients with myelopathy, whereas superolateral drainage was frequently observed in patients with SAH (P = 0.021). Thirty-six (94.7%) patients underwent microsurgery; of these, 33 (91.7%) had favorable outcomes and 3 (8.3%) had unfavorable outcomes. The main neurosurgical complications included acute hydrocephalus in 4 (10.5%) and new-onset mild persistent myelopathy in 6 (15.7%). According to the univariate analysis, the presence of myelopathy predicted poor outcomes, whereas SAH predicted favorable outcomes (P = 0.004). However, the multivariate analysis did not show statistical significance.

CONCLUSIONS

SAH is a common presenting sign of CJDAVF that may be overlooked on initial cerebral angiography, especially in patients with acute hydrocephalus and a low-flow fistula without varicose veins. Microsurgery involving disconnecting the draining vein is effective and beneficial. Further studies should be performed to investigate predictive factors influencing the prognosis.

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.

Benign Enhancing Foramen Magnum Lesions: Clinical Report of a Newly Recognized Entity

Intradural extramedullary foramen magnum enhancing lesions may be due to meningioma, nerve sheath tumor, aneurysm, or meningeal disease. In this clinical report of 14 patients, we describe a novel imaging finding within the foramen magnum that simulates disease. The lesion is hyperintense on 3D-FLAIR and enhances on 3D gradient-echo sequences but is not seen on 2D-TSE T2WI. It occurs at a characteristic location related to the posterior aspect of the intradural vertebral artery just distal to the dural penetration. Stability of this lesion was demonstrated in those patients who underwent follow-up imaging. Recognition of this apparently benign lesion may prevent unnecessary patient anxiety and repeat imaging.