Flow Diverter Treatment Using a Flow Re-Direction Endoluminal Device for Unruptured Intracranial Vertebral Artery Dissecting Aneurysm: Single-Center Case Series and Technical Considerations.

PURPOSE: This study aimed to evaluate the effectiveness, safety, and technical considerations of flow diverter (FD) treatment using a Flow Re-direction Endoluminal Device (FRED) for unruptured intracranial vertebral artery dissecting aneurysms (VADAs). MATERIALS AND METHODS: We conducted a retrospective study of 23 patients with unruptured intracranial VADAs who underwent FD treatment using a FRED between June 2017 and August 2021. Symptoms, imaging findings, treatment strategies, and angiographic and clinical outcomes were evaluated. Dissections were categorized according to the dominance of the VA in which they occurred: dominant VA, co-dominant VA, and non-dominant VA. RESULTS: All patients successfully underwent FD treatment with either a FRED (n=11) or FRED Jr. (n=12). Complete occlusion rates were 78.3% at 6-month follow-up magnetic resonance angiography and 91.3% at 12-month. There were no instances of complications, recurrence, or retreatment during a median follow-up of 20 months. Dissections occurred in the dominant VA in 3 cases (13.0%), the co-dominant VA in 13 cases (56.5%), and the non-dominant VA in 7 cases (30.4%). Intimal flap and true lumen stenosis were observed in 39.1% and 30.4% of cases, respectively. Four cases required a bilateral VA approach due to technical difficulties, all in the non-dominant VA. CONCLUSION: Flow diversion treatment using a FRED for unruptured intracranial VADAs proved feasible and safe, yielding satisfactory occlusion rates. Technical challenges were more likely in lesions involving non-dominant VAs in the acute or subacute stage, mainly due to associated intraluminal lesions compromising the arterial lumen.

Addendum: Outpatient Day-Care Management of Unruptured Intracranial Aneurysm: A Retrospective Cohort Study.

This corrects the article on p. 828 in vol. 23, PMID: 35762182.

Physiologic Flow Diversion Coiling Technique for Wide-Necked Aneurysms with an Asymmetric Bidirectional Flow at the Aneurysm Neck.

PURPOSE: Wide-necked aneurysms in the circle of Willis (CoW) are prone to recur due to reciprocal bidirectional flow. We present a novel concept of coil embolization to prevent recurrence that uses physiologic flow diversion at the CoW. MATERIALS AND METHODS: We enrolled 14 patients (15 aneurysms) who underwent aneurysm coiling for wide-necked aneurysms with asymmetric bidirectional inflow into the aneurysm. Four patients had recurrent aneurysms after coiling. The concept of physiologic flow diversion included obliterating antegrade flow into the aneurysm sac as well as opposite CoW flow by performing compact coil packing with intentional protrusion out of the aneurysm neck to the communicating part. RESULTS: Fifteen aneurysms, including 4 recurrent aneurysms, in an anterior communicating artery (n=7), posterior communicating artery (n=5), and tip of the basilar artery (n=3) were treated with coil embolization (n=10) and stent-assisted coiling (n=5). All aneurysms had a wide neck, and the mean largest diameter was 9.0 mm. The mean packing density was 45.1%. Twelve aneurysms were completely occluded, and 3 aneurysms had tiny residual neck remnants. There was neither a neurological event nor recurrence during the mean 12.5 months of follow-up. CONCLUSION: Wide-necked aneurysms at the CoW tend to recur. As a strategy to prevent a recurrence, physiologic flow diversion can be an option in treating wide-necked aneurysms in the CoW.

Preventive effects of ginseng against atherosclerosis and subsequent ischemic stroke: A randomized controlled trial (PEGASUS trial).

Background: Korean Red Ginseng (KRG) extract has been shown to have beneficial effects in patients with atherosclerosis, suggesting that KRG extract may be effective in preventing subsequent ischemic stroke in patients with severe atherosclerosis. Methods: This double-blind, placebo-controlled trial randomized patients with severe atherosclerosis in major intracranial arteries or extracranial carotid artery, to ginseng group and placebo group. They were given two 500-mg KRG tablets or identical placebo tablets twice daily for 12 months according to randomization. The primary endpoint was the composite of cerebral ischemic stroke and transient ischemic attack during 12 months after randomization. The secondary endpoints were change in volumetric blood flow of the intracranial vessels and the incidence of newly developed asymptomatic ischemic lesions. Any adverse events were monitored. Results: Fifty-eight patients were randomized from June 2016 to June 2017, 29 to ginseng and 29 to placebo, and 52 (28 and 24, respectively) completed the study. One patient in the placebo group, but none in the ginseng group, experienced ischemic symptoms (p = 0.46). Changes in volumetric blood flow and the presence of ischemic brain lesions did not differ significantly in the two groups, and none of these patients experienced adverse drug reactions. Conclusion: Ginseng was well tolerated by patients with severe atherosclerosis, with these patients showing good compliance with ginseng dosing. Ginseng did not show significant effects compared with placebo, although none of the ginseng-treated patients experienced ischemic events. Long-term studies in larger patient populations are required to test the effect of ginseng.

Clinical Manifestation and Radiologic Patterns of Spontaneous Cervicocephalic Dissection According to the Anatomic Location: A Single-Center Analysis in Korean Patients.

PURPOSE: Spontaneous cervicocephalic dissection (SCAD) is an important cause of stroke and shows various lesion locations and clinical features. The purpose of this study was to analyze the location of SCAD and its clinical and radiologic patterns in Korean patients. MATERIALS AND METHODS: Patients with SCAD who were evaluated between 2013 and 2018 at a tertiary center in Korea were reviewed. We classified and compared the morphological (aneurysm or steno-occlusion) and presenting (hemorrhage or infarction) patterns according to the lesion locations (anterior circulation [AC] vs. posterior circulation [PC]; intradural [ID] vs. extradural [ED]). RESULTS: A total of 166 patients were included in this study. The SCAD most commonly occurred in the PC-ID location (65.1%), followed by AC-ID (13.3%), AC-ED (13.3%), and PC-ED (8.4%). Aneurysm and steno-occlusion patterns were observed in 66.9% and 57.8% of the cases, respectively. The aneurysm pattern was significantly more common in the PC-ID location (78.7%) than in other locations. As for the presenting pattern, cerebral infarction was the most common pattern (39.8%), and intracranial hemorrhage was observed only in the ID location (7.2%). CONCLUSION: In Korean patients, PC-ID, especially ID vertebral artery, was the most common location of SCAD, and most cases were accompanied by an aneurysm. It also suggested that these location trends differ by population or ethnicity.

Etiology-Related Outcome of Endovascular Therapy in Posterior Circulation Stroke Compared to Anterior Circulation Stroke.

BACKGROUND AND PURPOSE: We investigated the impact of stroke etiology on the endovascular treatment (EVT) procedure and clinical outcome of posterior circulation stroke (PCS) patients with EVT compared to anterior circulation stroke (ACS) patients. METHODS: We retrospectively analyzed ischemic stroke patients who underwent EVT between January 2012 and December 2020. Enrolled ACS and PCS patients were compared according to etiologies (intracranial arterial steno-occlusion [ICAS-O], artery-to-artery embolic occlusion [AT-O], and cardioembolic occlusion [CA-O]). EVT procedure and favorable clinical outcomes at 3 months (modified Rankin Scale 0-2) were compared between the ACS and PCS groups for each etiology. RESULTS: We included 419 patients (ACS, 346; PCS, 73) including 88 ICAS-O (ACS, 67; PCS, 21), 66 AT-O (ACS, 50; PCS, 16), and 265 CA-O (ACS, 229; PCS, 36) patients in the study. The onset-to-recanalization time was longer in the PCS group than in the ACS group (median 628.0 minutes vs. 421.0 minutes, P=0.01). In CA-O patients, the door-to-puncture time was longer, whereas the puncture-to-recanalization time was shorter in the PCS group than in the ACS group. The proportions of successful recanalization and favorable clinical outcomes were similar between the ACS and PCS groups for all three etiologies. Low baseline National Institutes of Health Stroke Scale (NIHSS) scores and absence of intracerebral hemorrhage at follow-up imaging were associated with favorable clinical outcomes in both groups, whereas successful recanalization (odds ratio, 11.74; 95% confidence interval, 2.60 to 52.94; P=0.001) was only associated in the ACS group. CONCLUSIONS: The proportions of successful recanalization and favorable clinical outcomes were similar among all three etiologies between PCS and ACS patients who underwent EVT. Initial baseline NIHSS score and absence of hemorrhagic transformation were related to favorable outcomes in the PCS and ACS groups, whereas successful recanalization was related to favorable outcomes only in the ACS group.

Reversible Symptom Aggravation by Intake of Taurine-Rich Foods in Patients with Venous Congestive Myelopathy: Controlled Case Series Study.

PURPOSE: Reversible aggravation of myelopathy symptoms was observed after the intake of taurine-rich foods in patients with venous congestive myelopathy (VCM) caused by a spinal arteriovenous shunt (SAVS), and the taurine-challenge test was applied to demonstrate an association between taurine and VCM. MATERIALS AND METHODS: The current study reviewed any aggravation history of myelopathy symptoms, including walking difficulty, after consuming taurine-rich foods among 133 consecutive patients with a SAVS from a prospective institutional database from June 2013 to February 2021. The type of taurine-rich foods, demographic data, arteriovenous shunt level, and follow-up periods were obtained. For the controlled taurine challenge test, Bacchus® (Dong-A Pharmaceutical, Seoul, Korea), a taurine-rich drink, was given to patients who fulfilled test criteria of recovered VCM (pain-sensory-motor-sphincter scale ≥2, improvement of spinal cord signal intensity on magnetic resonance imaging, and follow-up >6 months after SAVS treatment) to confirm the disappearance of such aggravation. RESULTS: Ten patients had an aggravation history related to food. Webfoot octopus, small octopus, squid, crab, scallop, and taurine-rich energy drink (Bacchus®) were related to such aggravation in patients with VCM. Aggravation appeared about 30 minutes after food intake followed by expressions such as 'I could not walk and collapsed to the ground' and usually lasted for about 3 hours, followed by a slow recovery after taking rest. Four patients who met the test criteria underwent the taurine challenge with Bacchus® and revealed no further symptom aggravation, suggesting that taurine did not affect patients after recovery from VCM. CONCLUSION: The association between taurine-rich food and reversible symptom aggravation can appear in patients with VCM and disappear after VCM treatment. Aggravation of venous hypertension in the spinal cord is suggested as a mechanism but further elucidation is needed.

Outpatient Day-Care Management of Unruptured Intracranial Aneurysm: A Retrospective Cohort Study.

OBJECTIVE: This study aimed to assess the outcomes of outpatient day-care management of unruptured intracranial aneurysm (UIA), and to present the risks associated with different management strategies by comparing the outcomes and adverse events between outpatient day-care management and management with longer admission periods. MATERIALS AND METHODS: This retrospective cohort study used prospectively registered data and was approved by a local institutional review board. We enrolled 956 UIAs from 811 consecutive patients (mean age ± standard deviation, 57 ± 10.7 years; male:female = 247:564) from 2017 to 2020. We compared the outcomes after embolization among the different admission-length groups (1, 2, and ≥ 3 days). The outcomes included pre- and post-modified Rankin Scale (mRS) scores and rates of adverse events, cure, recurrence, and reprocedure. Events were defined as any cerebrovascular problems, including minor and major stroke, death, or hemorrhage. RESULTS: The mean admission period was 2 days, and 175 patients (191 aneurysms), 551 patients (664 aneurysms), and 85 patients (101 aneurysms) were discharged on the day of the procedure, day 2, and day 3 or later, respectively. During the mean 17-month follow-up period (range 6-53 months; 2757 patient years), no change in post-mRS was observed compared to pre-mRS in 99.6% of patients. Cure was achieved in 95.6% patients; minimal recurrence that did not require re-procedure occurred in 3.5% patients, and re-procedure was required in 2.3% (22 of 956) patients due to progressive enlargement of the recurrent sac during follow up (mean 17 months, range, 6-53 months). There were eight adverse events (0.8%), including five cerebrovascular (two major stroke, two minor strokes and one transient ischemic stroke), and three non-cerebrovascular events. Statistical comparison between groups with different admission lengths (1, 2, and ≥ 3 days) revealed no difference in the outcomes. CONCLUSION: This study revealed no difference in outcomes and adverse events according to the admission period, and suggested that UIA could be managed by outpatient day-care embolization.

Whole Exome Sequencing in Patients with Phenotypically Associated Familial Intracranial Aneurysm.

OBJECTIVE: Familial intracranial aneurysms (FIAs) are found in approximately 6%-20% of patients with intracranial aneurysms (IAs), suggesting that genetic predisposition likely plays a role in its pathogenesis. The aim of this study was to identify possible IA-associated variants using whole exome sequencing (WES) in selected Korean families with FIA. MATERIALS AND METHODS: Among the 26 families in our institutional database with two or more IA-affected first-degree relatives, three families that were genetically enriched (multiple, early onset, or common site involvement within the families) for IA were selected for WES. Filtering strategies, including a family-based approach and knowledge-based prioritization, were applied to derive possible IA-associated variants from the families. A chromosomal microarray was performed to detect relatively large chromosomal abnormalities. RESULTS: Thirteen individuals from the three families were sequenced, of whom seven had IAs. We noted three rare, potentially deleterious variants (PLOD3 c.1315G>A, NTM c.968C>T, and CHST14 c.58C>T), which are the most promising candidates among the 11 potential IA-associated variants considering gene-phenotype relationships, gene function, co-segregation, and variant pathogenicity. Microarray analysis did not reveal any significant copy number variants in the families. CONCLUSION: Using WES, we found that rare, potentially deleterious variants in PLOD3, NTM, and CHST14 genes are likely responsible for the subsets of FIAs in a cohort of Korean families.

Embolization Tactics of Spinal Epidural Arteriovenous Fistulas.

PURPOSE: Spinal epidural arteriovenous fistulas (SEDAVFs) show an epidural venous sac often with venous congestive myelopathy (VCM) due to intradural reflux at a remote level to which a transarterial approach would be difficult. We present 12 cases of SEDAVF with VCM and describe 3 main tactics for effective transarterial embolization. MATERIALS AND METHODS: Among 152 patients with spinal vascular malformations diagnosed in our tertiary hospital between 1993 and 2019, 12 SEDAVF patients with VCM were included. Three different transarterial embolization tactics were applied according to the vascular configuration and microcatheter accessibility. We evaluated treatment results and clinical outcomes before and after treatment. RESULTS: Transarterial embolization with glue (20-30%) was performed in all patients. The embolization tactics applied in 12 patients were preferential flow (n=2), plug-and-push (n=6), and filling of the venous sac (n=4). Total occlusion of the SEDAVF, including intradural reflux, was achieved in 11 (91.7%) of 12 patients, and partial occlusion was achieved in 1 patient. No periprocedural complications were reported. Spinal cord edema was improved in all patients for an average of 18 months after treatment. Clinical functional outcome in terms of the pain, sensory, motor, and sphincter scale and modified Rankin scores improved during a mean 25-month follow-up (6.3 vs. 3.3, P=0.002; 3.6 vs. 2.3, P=0.002, respectively). CONCLUSION: Endovascular treatment for 12 SEDAVF patients with VCM achieved a total occlusion rate of 91.7% without any periprocedural complication. The combined embolization tactics can block intradural reflux causing VCM, resulting in overall good clinical outcomes.

Microcatheter Stabilization Technique Using Partially Inflated Balloon for Coil Embolization of Paraclinoid Aneurysms.

PURPOSE: Coil embolization of paraclinoid aneurysms should be simple, safe, and effective considering the benign nature of the aneurysm. Here, we present a microcatheter stabilization technique using a partially inflated balloon for the treatment of paraclinoid aneurysms. MATERIALS AND METHODS: This retrospective study included 58 patients who underwent balloon-assisted coiling (BAC) for unruptured paraclinoid aneurysms at a tertiary neuro-intervention center between January 2019 and March 2020. We applied a technique to stabilize the microcatheter's position using the modified BAC technique in paraclinoid aneurysms showing various projections around the ophthalmic curve of the internal carotid artery. The basic concept of the technique is to place a partially inflated balloon just distal to the aneurysm neck and support the distal curve of the microcatheter using the proximal bottom of the balloon. Immediate radiological outcomes were analyzed, and clinical outcomes were evaluated with modified Rankin Scale (mRS) scores. RESULTS: The BAC was successfully performed in 51 of 58 patients (88%). We treated the remaining 7 patients by switching to stent-assisted coiling. We obtained a 37% mean packing density resulting in favorable occlusion in all 58 aneurysms (complete occlusion in 35 and residual neck in 23). There were no intraprocedural thromboembolic or hemorrhagic events except one that revealed an asymptomatic infarction after the procedure (1.7%). Magnetic resonance angiography follow-up was performed in 37 patients at an average of 11.8 months, in which 11 minor recurrences (29.7%) were found. There was no major recurrence nor retreatment. The mRS score was 0 in all patients during a mean follow-up of 17.7 months (range, 12-25 months). CONCLUSION: The modified balloon-assisted coiling technique using a partially inflated balloon was safe and effective and could serve as an option for treating paraclinoid aneurysms.

Rare Neurovascular Diseases in Korea: Classification and Related Genetic Variants.

Rare neurovascular diseases (RNVDs) have not been well-recognized in Korea. They involve the central nervous system and greatly affect the patients' lives. However, these diseases are difficult to diagnose and treat due to their rarity and incurability. We established a list of RNVDs by referring to the previous literature and databases worldwide to better understand the diseases and their current management status. We categorized 68 RNVDs based on their pathophysiology and clinical manifestations and estimated the prevalence of each disease in Korea. Recent advances in genetic, molecular, and developmental research have enabled further understanding of these RNVDs. Herein, we review each disease, while considering its classification based on updated pathologic mechanisms, and discuss the management status of RNVD in Korea.

Staged Approach for Stent-Assisted Coiling of Cerebral Aneurysms after Failure of Initial Intra-Saccular Catheterization.

PURPOSE: Microcatheter navigation into an aneurysm sac can present difficulties through negative interactions between the deployed stent mesh and microcatheter. We hypothesized that endothelialization of the stent mesh would minimize these interactions. We aimed to assess the feasibility of staged coiling after stenting by reviewing our experiences with unavoidably staged embolization cases. MATERIALS AND METHODS: Between 2011 and 2019, 7 patients (mean age 57.2 years, range 49-76 years) including 5 females, experienced 9 unruptured aneurysms treated with staged stenting and coiling due to unstable microcatheter navigation into the aneurysm after stent placement. The aneurysms were in the paraclinoid internal carotid artery (ICA) (n=3), ophthalmic origin ICA (n=1), superior cerebellar artery origin (n=2), basilar tip (n=2), and the middle cerebral artery bifurcation (n=1). The stents used were the Neuroform Atlas (n=4), Neuroform EZ (n=2), and Low-profile Visualized Intraluminal Support Blue (n=1). RESULTS: The mean interval between stenting and coiling was 15 weeks (range, 12-21 weeks). The average navigation time between the first roadmap imaging and microcatheter insertion in the sac was 14 minutes (range, 8-20 minutes). One aneurysm was occluded without further coiling on follow-up. Staged coiling successfully treated the remaining aneurysms (n=8). No complications were identified. CONCLUSION: In cases of difficult intra-saccular catheterization, intentional staged coiling may be a feasible option for stent-assisted coiling of the cerebral aneurysms.

Clinical Outcomes of Endovascular Treatment for Carotid Artery Dissection Without Intracranial Large Vessel Occlusion in Patients With Cerebral Ischemia Presentation.

BACKGROUND AND PURPOSE: We describe the clinical characteristics and outcomes (including the long-term patency of endovascular treatment [EVT]) of patients with acute ischemic strokes (AISs) featuring carotid artery dissection (CAD) but not intracranial large vessel occlusion. METHODS: We retrospectively reviewed patients who underwent EVT for spontaneous or post-traumatic AISs with CAD over a 13 year period from September 2005 to November 2018. The indications for EVT in patients with AIS-related CAD were a pretreatment diffusion-weighted imaging-Alberta Stroke Program early computed tomography (ASPECT) score > 6 and, clinical-diffusion mismatch. But, if the patients showed fluctuated ischemic symptoms, the joint decision by a stroke neurologist and neurointerventionist was done according to the onset-to-door time, symptoms, patient data, and the initial neuroimaging findings whether indicated that EVT was appropriate. RESULTS: Twenty-two dissected carotid arteries underwent balloon angioplasty and/or stent placement. The patients were 6 women and 16 men of median age 46 years. Twelve lacked any trauma history. Recombinant tissue plasminogen activator was prescribed for two (9.1%) patients. Four developed symptomatic intracranial hemorrhages (18.2%) but 86.4% exhibited modified Rankin scores ≤ 2. CONCLUSIONS: Although attention to the hemorrhagic complication is required, EVT for selective patients with cerebral ischemia associated with CAD may be safe and acceptable treatment strategy for reconstruction of luminal patency, with good clinical outcomes. Prospective large-scale randomized studies are required to optimize EVT for CAD patients.

Timing of Thrombosis in Embolization of Unruptured Intracranial Aneurysms : Tirofiban as Rescue Treatment.

PURPOSE: Thrombosis is one of the main complications of endovascular treatment for unruptured intracranial aneurysms (UIA). This article reports the timing and initial location of thrombosis and prognosis after the use of tirofiban for performing coil embolization for UIA. METHODS: This study retrospectively collected 1686 cases of intracranial aneurysms treated with coil embolization from January 2013 to February 2018. Ruptured cases were excluded. The presumed causes and timing of thrombosis, the response after tirofiban administration and the modified Rankin scale (mRS) score at 3 months were reviewed. RESULTS: Of the 26 patients 76% were female and middle cerebral artery and basilar artery aneurysms accounted for 7 cases. The initial location of thrombosis was related to the stent (n = 14, 53.8%) or coil (n = 12, 46.2%). Of the patients 19 (73.1%) developed thrombosis during the procedure, and 5 patients (19.2%) developed it within 1 day of the procedure. Median duration between the thrombotic procedure and initial thrombosis was 38.5 min, 12 patients were symptomatic but more than half completely recovered after using tirofiban. Good clinical outcome (mRS 0-2) was seen in 92.3%. In the subgroup analysis, median time from the first thrombotic procedure to initial thrombosis within 1 day was 38.0 min (stent-related group) and 35.0 min (coil-related group, p = 0.651). CONCLUSION: In most cases of embolization for UIA, thrombosis requiring the use of tirofiban occurs intraprocedurally or on the first day after the procedure. Careful observation of thrombosis during the procedure is important and tirofiban should be used for a better outcome even if the infarction progresses.

Direct Stenting of Intracranial Atherosclerosis-related Acute Large Vessel Occlusion.

PURPOSE: Endovascular reperfusion therapy (ERT) in patients with intracranial atherosclerosis (ICAS)-related acute large vessel occlusion (ALVO) may require different strategies based on the underlying culprit plaque lesion. This study investigated the effectiveness and safety of direct stent placement in ICAS-related ALVO compared with initially attempted mechanical thrombectomy (MT) with or without rescue treatment. METHODS: Direct stenting for ICAS-related ALVO was performed in 30 consecutive patients between January 1, 2012, and December 31, 2018. As a control for comparison, MT with or without rescue stenting for patients with ICAS-related ALVO was performed in 73 consecutive patients during the same period. Clinical outcomes were assessed by measuring modified Rankin Scale (mRS) at 90 days. RESULTS: Patients who underwent direct stenting and those who underwent MT with or without rescue stenting showed no significant differences in baseline characteristics. There was a higher proportion of patients with mRS 0-2 at 90 days in the direct stenting group than in the MT with or without rescue stenting group [24 (80.0%) vs. 34 (46.6%); p = 0.004]. Successful recanalization to modified thrombolysis in cerebral infarction category 2b or 3 was achieved in 93.3% of patients who underwent direct stenting, and in 90.4% of patients who underwent MT with or without rescue stenting. CONCLUSION: Direct stenting is an effective and safe option for ICAS-related ALVO. Further studies are needed to confirm that endovascular treatments are effective and safe in patients with ALVO and underlying ICAS.