ABSTRACT
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.
ABSTRACT
BACKGROUND: Early clinical trials validating endovascular therapy (EVT) for emergent large vessel occlusion (ELVO) ischemic stroke in the anterior circulation initially focused on patients with small or absent completed infarctions (ischemic cores) to maximize the probability of detecting a clinically meaningful and statistically significant benefit of EVT. Subsequently, real-world experience suggested that patients with large core ischemic strokes (LCS) at presentation may also benefit from EVT. Several large, retrospective, and prospective randomized clinical trials have recently been published that further validate this approach. These guidelines aim to provide an update for endovascular treatment of LCS. METHODS: A structured literature review of LCS studies available since 2019 and grading the strength and quality of the evidence was performed. Recommendations were made based on these new data by consensus of the authors, with additional input from the full SNIS Standards and Guidelines Committee and the SNIS Board of Directors. RESULTS: The management of ELVO strokes with large ischemic cores continues to evolve. The expert panel agreed on several recommendations: Recommendation 1: In patients with anterior circulation ELVO who present within 24 hours of last known normal with large infarct core (70-149 mL or ASPECTS 3-5) and meet other criteria of RESCUE-Japan LIMIT, SELECT2, ANGEL-ASPECT, TESLA, TENSION, or LASTE trials, thrombectomy is indicated (Class I, Level A). Recommendations 2-7 flow directly from recommendation 1. Recommendation 2: EVT in patients with LCS aged 18-85 years is beneficial (Class I, Level A). Recommendation 3: EVT in patients with LCS >85 years of age may be beneficial (Class I, Level B-R). Recommendation 4: Patients with LCS and NIHSS score 6-30 benefit from EVT in LCS (Class I, Level A). Recommendation 5: Patients with LCS and NIHSS score <6 and >30 may benefit from EVT in LCS (Class IIa, Level A). Recommendation 6: Patients with LCS and low baseline mRS (0-1) benefit from EVT (Class I, Level A). Recommendation 7: Patients with LCS and time of last known well 0-24 hours benefit from EVT (Class I, Level A). Recommendation 8: It is recommended that patients with ELVO LCS who also meet the criteria for on-label or guideline-directed use of IV thrombolysis receive IV thrombolysis, irrespective of whether endovascular treatments are being considered (Class I, Level B-NR). CONCLUSIONS: The indications for endovascular treatment of ELVO strokes continue to expand and now include patients with large ischemic cores on presentation. Further prospective randomized studies, including follow-up to assess the population-based efficacy of treating patients with LCS, are warranted.
