Application of artificial intelligence in brain arteriovenous malformations: Angioarchitectures, clinical symptoms and prognosis prediction.

BACKGROUND: Artificial intelligence (AI) has rapidly advanced in the medical field, leveraging its intelligence and automation for the management of various diseases. Brain arteriovenous malformations (AVM) are particularly noteworthy, experiencing rapid development in recent years and yielding remarkable results. This paper aims to summarize the applications of AI in the management of AVMs management. METHODS: Literatures published in PubMed during 1999-2022, discussing AI application in AVMs management were reviewed. RESULTS: AI algorithms have been applied in various aspects of AVM management, particularly in machine learning and deep learning models. Automatic lesion segmentation or delineation is a promising application that can be further developed and verified. Prognosis prediction using machine learning algorithms with radiomic-based analysis is another meaningful application. CONCLUSIONS: AI has been widely used in AVMs management. This article summarizes the current research progress, limitations and future research directions.

FMB: Dual-view fusion and registration of 2D DSA images and 3D MRA images for neurointerventional-based procedures.

OBJECTIVE: Alignment between preoperative images (high-resolution magnetic resonance imaging, magnetic resonance angiography) and intraoperative medical images (digital subtraction angiography) is currently required in neurointerventional surgery. Treating a lesion is usually guided by a 2D DSA silhouette image. DSA silhouette images increase procedure time and radiation exposure time due to the lack of anatomical information, but information from MRA images can be utilized to compensate for this in order to improve procedure efficiency. In this paper, we abstract this into the problem of relative pose and correspondence between a 3D point and its 2D projection. Multimodal images have a large amount of noise and anomalies that are difficult to resolve using conventional methods. According to our research, there are fewer multimodal fusion methods to perform the full procedure. APPROACH: Therefore, the paper introduces a registration pipeline for multimodal images with fused dual views is presented. Deep learning methods are introduced to accomplish feature extraction of multimodal images to automate the process. Besides, the paper proposes a registration method based on the Factor of Maximum Bounds (FMB). The key insights are to relax the constraints on the lower bound, enhance the constraints on the upper bounds, and mine more local consensus information in the point set using a second perspective to generate accurate pose estimation. MAIN RESULTS: Compared to existing 2D/3D point set registration methods, this method utilizes a different problem formulation, searches the rotation and translation space more efficiently, and improves registration speed. SIGNIFICANCE: Experiments with synthesized and real data show that the proposed method was achieved in accuracy, robustness, and time efficiency.

Physiological and transcriptomic analysis reveals the potential mechanism of Morinda officinalis How in response to freezing stress.

BACKGROUND: Morinda officinalis How (MO) is a vine shrub distributed in tropical and subtropical regions, known as one of the "Four Southern Herbal Medicines" in China. The unclear responsive mechanism by which MO adapt to freezing stress limits progress in molecular breeding for MO freezing tolerance. RESULTS: In this study, morphological, physiological and microstructure changes in MO exposed to -2℃ for 0 h, 3 h, 8 h and 24 h were comprehensively characterized. The results showed that freezing stress caused seedling dehydration, palisade cell and spongy mesophyll destruction. A significant increase in the content of proline, soluble protein and soluble sugars, as well as the activity of superoxide dismutase and peroxidase was observed. Subsequently, we analyzed the transcriptomic changes of MO leaves at different times under freezing treatment by RNA-seq. A total of 24,498 unigenes were annotated and 3252 unigenes were identified as differentially expressed genes (DEGs). Most of these DEGs were annotated in starch and sucrose metabolism, plant hormone signal transduction and MAPK signaling pathways. Family Enrichment analysis showed that the glucosyl/glucuronosyl transferases, oxidoreductase, chlorophyll a/b binding protein and calcium binding protein families were significantly enriched. We also characterized 7 types of transcription factors responding to freezing stress, among which the most abundant family was the MYBs, followed by the AP2/ERFs and NACs. Furthermore, 10 DEGs were selected for qRT-PCR analysis, which validated the reliability and accuracy of RNA-seq data. CONCLUSIONS: Our results provide an overall view of the dynamic changes in physiology and insight into the molecular regulation mechanisms of MO in response to freezing stress. This study will lay a foundation for freezing tolerance molecular breeding and improving the quality of MO.

Multimodality Treatment of Deep-seated Cerebral Arteriovenous Malformations: The Experiences of One Center.

OBJECTIVE: Treatment of deep-seated cerebral arteriovenous malformations (AVMs) remains challenging for neurosurgeons or neuroradiologists. This study aims to review the experiences of one center in using multimodality treatment for deep-seated AVMs. METHODS: The AVM database of Xuanwu Hospital, Capital Medical University was searched, and 96 patients who were diagnosed with a deep-seated cerebral AVM between 2010 and 2020 were identified. The following information was collected and analyzed: patients' clinical features, treatment modality used, posttreatment complications, AVM obliteration rate, rebleeding rate, and functional outcome during follow-up. The patients' posttreatment modified Rankin scale (mRS) scores were split into two groups: good outcome (mRS score ≤ 2) and poor outcome (mRS score ≥ 3). Univariate and multivariate logistic regression analyses were applied to test the predictors of clinical outcomes and AVM obliteration. RESULTS: Eighty-eight out of 96 patients (91.7%) presented with initial hemorrhaging. The pretreatment mRS score was ≤ 2 in 80 patients (88.3%) patients and ≥ 3 in 16 patients (16.7%). Limb weakness was present in 42 patients (43.8%). In this sample, 210 hemorrhages occurred during 2056 person-years before diagnosis, yielding an annual hemorrhage rate of 10.2% per person-year. Angiographic obliteration was achieved in 29 patients (30.2%). At the last follow-up, 80 patients (83.3%) had good clinical outcomes, whereas 16 (16.7%) had a deterioration in their clinical presentation following treatment. Multivariate analyses indicated that pretreatment limb weaknesses and a high Spetzler-Martin grade predicted poor clinical outcomes (P = 0.003 and 0.008, respectively). Fewer feeding arteries were a predictor for AVM obliteration (P = 0.034). CONCLUSION: Good outcomes can be achieved through multimodal treatment of deep-seated AVMs. A single supplying artery is a predictor of AVM obliteration. Pretreatment limb weaknesses and high Spetzler-Martin grades predict poor clinical outcomes.

Wrap-Clipping for Patients with Ruptured Blood Blister-Like Aneurysms of the Internal Carotid Artery: Case Series and Literature Review.

OBJECTIVE: Blood blister-like aneurysms (BBAs) of the internal carotid artery (ICA) are challenging to treat. We assessed the clinical and radiologic outcomes in patients with ruptured BBAs of the ICA treated with wrap-clipping. METHODS: From November 2016 to January 2020, the clinical and radiologic data of patients with subarachnoid hemorrhage (SAH) caused by ICA BBAs who underwent wrap-clipping were retrospectively analyzed. The clinical outcomes were evaluated according to the modified Rankin Scale (mRS). Radiologic follow-up examinations included digital subtraction angiography (DSA), computed tomography angiography (CTA), and magnetic resonance angiography (MRA). RESULTS: Seven patients were enrolled in this study. All BBAs were wrap-clipped successfully, including two BBAs that exhibited intraoperative bleeding and required balloon-assistance during surgery. All patients had favorable clinical outcomes during follow-up. Among the six patients who completed the radiologic follow-up visit, one patient presented ICA occlusion at the 6-month DSA follow-up, but no neurologic dysfunction was noted. We did not observe the progression of ICA stenosis in other patients. CONCLUSION: All BBAs in this study were wrap-clipped successfully and completely occluded. Wrap-clipping is effective for BBAs of the ICA and has favorable clinical outcomes. A multicenter study with a large sample size and a longer radiologic follow-up is necessary.

Risk Factors for Pericallosal Artery Aneurysm Rupture Based on Morphological Computer-Assisted Semiautomated Measurement and Hemodynamic Analysis.

Background: Although pericallosal artery aneurysms (PAAs) are relatively uncommon, accounting for only 1-9% of all intracranial aneurysms (IAs), they exhibit a considerably high propensity to rupture. Nevertheless, our current knowledge of the risk factors for PAA rupture is still very limited. To fill this gap, we investigated rupture risk factors for PAAs based on morphological computer-assisted semiautomated measurement (CASAM) and hemodynamic analysis. Methods: Patients with PAAs were selected from the IA database in our institute and their baseline data were collected. Morphological parameters were measured in all enrolled patients by applying CASAM. Computational fluid dynamics simulation (CFD) was performed to evaluate the hemodynamic difference between ruptured and unruptured PAAs. Results: From June 2017 to June 2020, among 2141 patients with IAs in our institute, 47 had PAAs (2.2%). Thirty-one patients (mean age 57.65 ± 9.97 years) with 32 PAAs (20 unruptured and 12 ruptured) were included in the final analysis. Comparing with unruptured PAAs, ruptured PAAs had significantly higher aspect ratio (AR), mean normalized wall shear stress (NWSS), and mean oscillatory shear index (OSI) values than the unruptured PAAs (all P < 0.05) in univariate analyses. Multivariable analysis showed that a high mean OSI was an independent risk factor for PAA rupture (OR = 6.45, 95% CI 1.37-30.32, P = 0.018). Conclusion: This preliminary study indicates that there are morphological and hemodynamic differences between ruptured and unruptured PAAs. In particular, a high mean OSI is an independent risk factor for PAA rupture. Further research with a larger sample size is warranted in the future.

Flow Diversion for Middle Cerebral Artery Aneurysms: An International Cohort Study.

BACKGROUND: Open surgery has traditionally been preferred for the management of bifurcation middle cerebral artery (MCA) aneurysms. Flow diverting stents present a novel endovascular strategy for aneurysm treatment. OBJECTIVE: To add to the limited literature describing the outcomes and complications in the use of flow diverters for the treatment of these complex aneurysms. METHODS: This is a multicenter retrospective review of MCA bifurcation aneurysms undergoing flow diversion. We assessed post-treatment radiological outcomes and both thromboembolic and hemorrhagic complications. RESULTS: We reviewed the outcomes of 54 aneurysms treated with flow diversion. Four (7.4%) of the aneurysms had a history of rupture (3 remote and 1 acute). Fourteen (25.9%) of the aneurysms already underwent either open surgery or coiling prior to flow diversion. A total of 36 out of the 45 aneurysms (80%) with available follow-up data had adequate aneurysm occlusion with a median follow-up time of 12 mo. There were no hemorrhagic complications but 16.7% (9/54) had thromboembolic complications. CONCLUSION: Flow diverting stents may be a viable option for the endovascular treatment of complex bifurcation MCA aneurysms. However, compared to published series on the open surgical treatment of this subset of aneurysms, flow diversion has inferior outcomes and are associated with a higher rate of complications.

Health-related quality of life outcomes and influencing factors in patients with unruptured intracranial aneurysms after endovascular treatment.

BACKGROUND: Health-related quality of life (HRQoL) is an important indicator when evaluating prognosis and disease-related treatments. Our current knowledge of the HRQoL outcomes of unruptured intracranial aneurysm (UIA) patients treated by the endovascular intervention appeared to be very limited. To fill this gap, the present study investigated the HRQoL outcomes and identified the influencing factors in UIA patients treated by endovascular intervention. METHODS: We conducted a single-center cross-sectional study on patients who underwent endovascular treatment for UIAs. HRQoL outcomes were assessed by the 36-item Short Form Health Survey (SF-36). The SF-36 results of the Chinese reference population were used as the reference data. The independent variables with a univariate analysis result of P < 0.05 were included in the multivariate analysis. Finally, multivariable linear regression analysis was performed to identify the factors influencing HRQoL. Bonferroni correction was utilized for multiple testing correction. RESULTS: A total of 200 patients (83 males and 117 females, mean age of 55.2 ± 9.48 years) with UIAs treated by endovascular intervention were enrolled. The scores of SF-36 in 8 domains for UIA patients treated by endovascular intervention did not all reach the average level of the Chinese reference population after an average recovery period of 30.67 ± 8.6 months. Ischemic cerebrovascular disease history, advanced age, and mRS progression at discharge were independent risk factors of HRQoL for UIA patients treated by endovascular intervention, but physical exercise at least once a week and daily sleep time no < 6 h were independent protective factors. CONCLUSION: The HRQoL of UIA patients treated by the endovascular intervention was decreased to varying degrees compared with those of the Chinese reference population. The influencing factors of HRQoL explored by this study provide insights for improving the clinical management and daily lives of these patients. HRQoL assessment should be included in future aneurysm prognostic studies to provide better evidence.

The sensitivity and specificity of TOF-MRA compared with DSA in the follow-up of treated intracranial aneurysms.

BACKGROUND: Time-of-flight magnetic resonance angiography (TOF-MRA) is widely used in detecting intracranial aneurysms (IA), but it is limited and controversial for use during follow-up to assess the outcome of interventional coiling or clipping surgery. METHODS: To evaluate the specificity and sensitivity of using TOF-MRA as an imaging follow-up for IA with different treatments. A total of 280 patients with 326 treated IA underwent simultaneous TOF-MRA and digital subtraction angiography (DSA) as follow-up imaging on the same day. All images were independently reviewed by two neurosurgeons and two radiologists. The consensus evaluation of intra-arterial DSA as a reference test was used to evaluate the result of aneurysm occlusions. The aneurysmal embolization status was assessed with two ratings involving complete or incomplete occlusions. We calculated the sensitivity, specificity, negative predictive value, and positive predictive value of three-dimensional-TOF-MRA to investigate the diagnostic performance. RESULTS: Overall sensitivity and specificity of TOF-MRA for diagnosing the remnant were 83.3% and 95.2%, respectively. The sensitivity and specificity of interventional therapy was 90.0% and 94.2%, respectively, while the clipping group showed sensitivity and specificity of 50.0% and 100%, respectively. For additional groups, involving coil only, stent-assisted, and flow diverter, the analysis of interventional therapy showed sensitivities and specificities of 100.0% and 90.1%, 66.7% and 95.1%, and 91.7% and 100%, respectively. CONCLUSIONS: TOF-MRA can be used as a first-line noninvasive imaging modality during follow-up, especially for the patients treated with a pipeline embolization device and coils only. But it may not be enough for clipped aneurysms.

Prevalence of and risk factors for anxiety and depression in Chinese patients with unruptured intracranial aneurysms treated by endovascular intervention.

BACKGROUND: Studies on anxiety and depression in unruptured intracranial aneurysm (UIA) patients after treatment via endovascular intervention are rare and controversial. We aimed to explore the prevalence of anxiety and depression among Chinese patients with UIAs treated by endovascular intervention and to identify which factors contribute to the development of these symptoms. METHODS: We performed a cross-sectional study on anxiety and depression in patients who underwent endovascular treatment for UIAs using the Hospital Anxiety and Depression Scale (HADS). The demographic, clinical and radiological data for all patients were retrospectively collected from the aneurysm database and medical records. Moreover, we utilized data from a large sample of 200 UIA patients and multivariate logistic regression analysis to investigate the risk factors for anxiety and depression in these patients. Candidate variables with P values less than 0.20 in univariate analysis were included in the multivariate logistic regression analysis. RESULTS: Two hundred patients returned completed questionnaires in this study. Of these 200 patients, 34 (17.0%) suffered from anxiety and 31 (15.5%) suffered from depression 30.67 ± 8.6 months after being discharged. The multivariate analysis results indicated that shorter sleep times were statistically significantly associated with depression (OR = 1.62, 95% CI: 1.14 ~ 2.29, P = 0.007, Adjusted P = 0.02). . CONCLUSION: The prevalences of anxiety and depression in UIA patients treated by endovascular intervention were 17.0 and 15.5%, respectively. Shorter sleep times were significantly associated with depression. Our findings provide evidence for the clinical and psychological management of these patients.

Using the modified Delphi method to research the influencing factors of long-term health-related quality of life in patients with unruptured intracranial aneurysms after endovascular treatment.

BACKGROUND: The purpose of this study was to use the modified Delphi method to identify the influencing factors of health-related quality of life (HRQoL) in patients with unruptured intracranial aneurysms (UIAs) after endovascular treatment. METHODS: A modified Delphi method to obtain expert consensus on the content of potential influencing factors of HRQoL in patients with UIAs treated by endovascular intervention was employed. The research team consists of three neuroradiologists and one epidemiologist from Xuanwu Hospital of Capital Medical University. They randomly selected 21 well-known experts in cerebrovascular disease diagnosis and treatment as participating experts. The importance of the indicator is based on the 5-Likert scale. The standard deviation (SD), coefficient of variation (CV), mean ( x ¯ ), and minimum and maximum scores of each indicator were calculated. The consistency was described by Kendall coefficient of concordance with a p value < 0.05 indicating that the expert consistency was high. RESULT: Twenty-one and 18 questionnaires were responded in 2 rounds, with effective response rates of 85.7% and 100.0%, respectively. The average authoritative coefficient (Cr) of all 21 experts was 0.88, familiarity with the indicators (Cs) was 0.82, and the judgment basis of the indicators (Ca) was 0.94. Eventually, the x ¯ values of arterial puncture hematoma, hyperlipidemia, gender, marital status, and hospitalization for other diseases were lower than 3.5; CV for marital status and gender was higher than 0.35. The Kendall coefficient of concordance in the first round was 0.19 (p < 0.001), and the second round was 0.15 (p < 0.001). CONCLUSION: In this study, the factors affecting the recovery of HRQoL after endovascular treatment in patients with UIAs were analyzed by the modified Delphi method, which provided a valuable evidence for the clinical management and daily life guidance for UIAs patients.

Fully automated intracranial aneurysm detection and segmentation from digital subtraction angiography series using an end-to-end spatiotemporal deep neural network.

BACKGROUND: Intracranial aneurysms (IAs) are common in the population and may cause death. OBJECTIVE: To develop a new fully automated detection and segmentation deep neural network based framework to assist neurologists in evaluating and contouring intracranial aneurysms from 2D+time digital subtraction angiography (DSA) sequences during diagnosis. METHODS: The network structure is based on a general U-shaped design for medical image segmentation and detection. The network includes a fully convolutional technique to detect aneurysms in high-resolution DSA frames. In addition, a bidirectional convolutional long short-term memory module is introduced at each level of the network to capture the change in contrast medium flow across the 2D DSA frames. The resulting network incorporates both spatial and temporal information from DSA sequences and can be trained end-to-end. Furthermore, deep supervision was implemented to help the network converge. The proposed network structure was trained with 2269 DSA sequences from 347 patients with IAs. After that, the system was evaluated on a blind test set with 947 DSA sequences from 146 patients. RESULTS: Of the 354 aneurysms, 316 (89.3%) were successfully detected, corresponding to a patient level sensitivity of 97.7% at an average false positive number of 3.77 per sequence. The system runs for less than one second per sequence with an average dice coefficient score of 0.533. CONCLUSIONS: This deep neural network assists in successfully detecting and segmenting aneurysms from 2D DSA sequences, and can be used in clinical practice.

TREM2 activation attenuates neuroinflammation and neuronal apoptosis via PI3K/Akt pathway after intracerebral hemorrhage in mice.

BACKGROUND: Neuroinflammation is an important host defense response to secondary brain injury after intracerebral hemorrhage (ICH). Triggering receptor expressed on myeloid cells 2 (TREM2) confers strong neuroprotective effects by attenuating neuroinflammation in experimental ischemic stroke. Recent studies suggest that apolipoprotein E (apoE) is a novel, high-affinity ligand of TREM2. This study aimed to investigate the effects of TREM2 activation on neuroinflammation and neuronal apoptosis in a mouse model of ICH. METHODS: Adult male CD1 mice (n = 216) were subjected to intrastriatal injection of bacterial collagenase. The TREM2 ligand, apoE-mimetic peptide COG1410 was administered intranasally at 1 h after ICH induction. To elucidate the underlying mechanism, TREM2 small interfering RNA (siRNA) and the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 were administered intracerebroventricularly prior to COG1410 treatment. Neurobehavioral tests, brain water content, immunofluorescence, western blotting, and Fluoro-Jade C- and terminal deoxynucleotidyl transferase dUTP nick end labeling staining were performed. RESULTS: Endogenous TREM2 expression was increased and peaked at 24 h after ICH. TREM2 was expressed on microglia, astrocytes, and neurons. COG1410 improved both short-term and long-term neurological functions, reduced brain edema, inhibited microglia/macrophage activation and neutrophil infiltration, and suppressed neuronal apoptotic cell death in perihematomal areas after ICH. Knockdown of endogenous TREM2 by TREM2 siRNA aggravated neurological deficits and decreased the expression of TREM2 in naïve and ICH mice. COG1410 was associated with upregulation of TREM2, PI3K, phosphorylated-Akt, and Bcl-2 and downregulation of TNF-α, IL-1ß, and Bax after ICH. The neuroprotective effects of COG1410 were abolished by both TREM2 siRNA and PI3K inhibitor LY294002. CONCLUSIONS: Our finding demonstrated that TREM2 activation improved neurological functions and attenuated neuroinflammation and neuronal apoptosis after ICH, which was, at least in part, mediated by activation of PI3K/Akt signaling pathway. Therefore, activation of TREM2 may be a potential therapeutic strategy for the management of ICH patients.

Microsurgical and Endovascular Treatment Outcomes in Pericallosal Artery Aneurysms: A Single Center Retrospective Analysis.

AIM: To summarize the clinical outcomes, follow-up results and to discuss the optimal therapeutic strategy for pericallosal artery aneurysms (PAAs). MATERIAL AND METHODS: From January 2013 to May 2017, the charts of 49 patients with PAAs, representing 2.43% of 2,018 consecutive patients with intracranial aneurysms (IAs) were reviewed. The clinical and radiological data of these patients were retrospectively analyzed. RESULTS: There were no technical failures in the clipping group, but one patient in the coiling group presented rebleeding during the operation, resulting in a poor prognosis. Although the difference was not significant, the coiling group had a better complete recovery rate than the clipping group [overall: coiling, n=20 (87.0%) vs clipping, n=11 (68.8%), p=0.33; unruptured PAAs: coiling, n=12 (92.3%) vs clipping, n=5 (83.3%); ruptured PAAs: coiling, n=8 (80%) vs clipping, n=6 (60%), p=0.63]. One patient in the coiling group exhibited recurrence. No patients experienced rebleeding during the follow-up period in either group. CONCLUSION: In our study, both endovascular coiling and microsurgery were technically feasible and achieved favorable clinical outcomes in patients with PAAs. Longer radiological follow-up is necessary. Patients should be evaluated by a multidisciplinary team prior to determining the optimal treatment modality.

The natural course of unruptured intracranial aneurysms in a Chinese cohort: protocol of a multi-center registration study in CIAP.

BACKGROUND: Subarachnoid hemorrhage (SAH) accounts for 4.4% of cerebral vascular disease, which is one of the leading causes of death in China. Rupture of intracranial aneurysms (IAs) is the most common cause of SAH. The natural history of unruptured IAs (UIAs) and the risk factors for rupture are among the key issues regarding the pathogenesis of IA and SAH that remain unclear in the Chinese population. METHODS: The China Intracranial Aneurysm Project (CIAP) is a prospective, observational, multicenter registry study of the natural courses, risk factors for the onset and rupture, treatment methods, comorbidity management and other aspects of intracranial aneurysms. To date, there are five studies in the CIAP. CIAP-1 is a prospective observational cohort study of UIAs. More than 5000 patients who will be followed for at least 1 year are expected to be enrolled in this cohort. These participants come from more than 20 centers that represent different regions in China. Enrollment began on May 1, 2017, and will take approximately 5 years. A nationwide online database of UIAs will be built. Participants' basic, lifestyle, clinical and follow-up information will be collected. The blood samples will be stored in the Central Biological Specimen Bank. Strict standards have been established and will be followed in this study to ensure efficient implementation. DISCUSSION: The natural course of UIAs in the Chinese population will be explored in this registry study. In addition, the risk factors for the rupture of the UIAs and the joint effect of those factors will be analyzed. The present study aims to create a nationwide database of UIAs and investigate the natural course of UIAs in China. Trial registration The Natural Course of Unruptured Intracranial Aneurysms in a Chinese Cohort (ClinicalTrials.gov Identifier: NCT03117803). Registered: July 5, 2017.

Natural history of spinal cord arteriovenous shunts: an observational study.

The natural history of intradural spinal cord arteriovenous shunts is unknown. We performed an observational study in a consecutive patient cohort with symptomatic intradural spinal cord arteriovenous shunts who were admitted to three institutes to investigate the clinical course of this complex disease, which would provide valuable evidence to inform clinical decision-making. The clinical course of patients with symptomatic intradural spinal cord arteriovenous shunts from initial presentation to occurrence of clinical deterioration, initiation of treatment, or last follow-up was analysed. Patients with at least 1 month of observation were included in this study. Clinical onset and deterioration patterns were divided into acute and gradual. Annual and cumulative rates of clinical deterioration as well as their risk factors were analysed using Kaplan-Meier life table analysis and Cox proportional hazards model. To assess risks and benefits of treatment, post-treatment clinical courses were further assessed. Four hundred and sixty-six patients with a mean observational period of 36.9 ± 58.8 months were included; 56.7% of patients presented with acute onset, of whom 77.3% experienced spontaneous recovery. Age of onset older than 28 years, initial modified Aminoff and Logue scale of >3, mid-thoracic lesions and non-ventral lesions were independent predictors of failure for spontaneous recovery. The annual risk of general, acute and gradual clinical deterioration after onset was 30.7%, 9.9% and 17.7%, respectively. Risk of deterioration was highest in the early period after initial onset. Acute onset was the only independent risk factor [hazard ratio 1.957 (95% confidence interval, CI 1.324-2.894); P = 0.0008] of acute deterioration and gradual onset was the strongest predictor [hazard ratio 2.350 (95% CI 1.711-3.229); P < 0.0001] of the gradual deterioration among all the stratifying factors. After invasive treatment, complete obliteration was achieved in 37.9% of patients (138 of 364) and improved or stable clinical status was noted in 80.8% of patients. Forty-two patients (11.5%) experienced permanent complications. Overall post-treatment deterioration rate was 8.4%/year, and 5.3%/year if permanent complications were excluded. The natural history of symptomatic spinal cord arteriovenous shunts is poor, especially in the early period after onset, and early intervention is thus recommended. Initial onset pattern significantly affects the natural history of the lesion, which prompts a differentiated treatment strategy.

Reconstructive endovascular treatment of the V4 segment of a vertebral artery dissecting aneurysm with the Willis covered stent: A retrospective study.

OBJECTIVE: Preliminary studies suggest that Willis covered stents may be suitable for the treatment of aneurysms of the internal carotid artery (ICA), but their efficacy and safety in vertebral artery (VA) dissecting aneurysms need further investigation. METHODS: Consecutive patients who underwent placement of a Willis covered stent for treatment of an aneurysm of the V4 segment of the VA between September 2015 and December 2017 at our institution were retrospectively reviewed. The efficacy, complications, angiographic and clinical follow-up results were collected and analyzed. RESULTS: Sixteen covered stents were successfully implanted into the VA in 12 patients with 12 dissecting aneurysms. The technical success rate of stenting placement was 100%. Complete occlusion was achieved in 11 patients immediately after stent placement, with transient endoleak in one aneurysm. Angiographic follow-up (9.9 ± 4.0 months, mean±SD) was performed in nine patients and demonstrated complete stabilization of the obliterated aneurysm. Clinical follow-up (20.1 ± 9.6 months, mean±SD) demonstrated full recovery in 11 patients, and one patient suffered from acute myocardial infarction. CONCLUSION: Reconstruction using a Willis covered stent is an efficient, safe and attractive alternative for the definitive treatment of intracranial VA dissecting aneurysms; longer follow-up and expanded clinical trials are needed for further validation of this technique.

Spontaneous Spinal Epidural Hematoma: A Study of 55 Cases Focused on the Etiology and Treatment Strategy.

BACKGROUND: Spontaneous spinal epidural hematoma (SSEH) is a rare neurologic emergency of the spinal cord. Its cause and treatment strategy remain controversial. This study aimed to evaluate a significant cause of SSEH and to discuss the treatment strategy according to the clinical outcomes of patients in 2 institutions. METHODS: Fifty-five cases of SSEH treated at our institutions between February 2002 and February 2016 were retrospectively analyzed. RESULTS: The mean age of the first SSEH onset was 31.8 years. The follow-up rate was 72.7%, with 28 patients (70%) showing satisfactory clinical outcomes. Forty patients received preoperative spinal digital subtraction angiography. Spinal epidural (extradural) arteriovenous fistula was detected in 6 patients (15%), 5 of whom showed 1 type of special slow-flow shunt. Nineteen patients (34.5%) suffered from multiple episodes until they underwent invasive treatments or last follow-up. Rebleeding was confirmed in 8 patients. None of the patients had a subsequent episode or rebleeding after invasive treatment. The risk factors for poor clinical outcome included advanced age at initial onset (P = 0.020), a short progression interval (P = 0.030), no symptom relief after admission (P = 0.011), hypesthesia (P = 0.017), complete spinal cord injury (P = 0.001), and hematoma below the T4 level (P = 0.014). CONCLUSIONS: Spinal epidural (extradural) arteriovenous fistula is a significant cause of SSEH. Standard spinal digital subtraction angiography is necessary for patients with SSEH. Conservative treatment could not prevent occurrence of multiple episodes or rebleeding in patients. Microsurgery should be recommended as the preferred treatment strategy for SSEH. Endovascular embolization is also recommended if applicable.