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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Tailored antiplatelet agent medication in clopidogrel hyporesponsive patients before stent-assisted coiling: single-center experience

PURPOSE

In patients requiring stent procedures, resistance or hyperresponsiveness to antiplatelet medications is often observed. This study aims to evaluate the efficacy and safety of tailoring medications in these patients.

METHODS

This retrospective study included 223 patients who underwent endovascular treatment for intracranial aneurysm between October 2018 and October 2019. Patients were categorized as hyporesponsive, hyperresponsive, and normoresponsive groups according to the initial PRU response. For the hypo- or hyperresponders, we tailored medication by modifying the dose or changing the drug. PRUs before and after tailoring were compared in each group. PRU reponses in patients who underwent Cytochrome P450 2C19 (CYP2C19) genotyping were also determined.

RESULTS

Of the 73 clopidogrel-resistant patients, the mean PRU values after tailoring showed a greater decrease in the group that switched to prasugrel (n = 56), from 223 to 131, than in the clopidogrel reloading group (n = 17), from 238 to 209. In 31 hyperresponders, PRU increased from 49 to 94 after the dose adjustment. CYP2C19 genotyping showed that PRU tended to increase as the number of mutated alleles increased. There were five (2.3%) ischemic events (three transient ischemic attacks and two minor strokes) in a mean follow-up of 8 months, but no hemorrhage.

CONCLUSIONS

The stent-assisted coiling was successfully performed with acceptable range of ischemic events and without hemorrhage in all patients, including those who applied tailored medication. Low-dose prasugrel was effective for obtaining appropriate PRU values for initial medication as well as for clopidogrel-resistant patients. The genetic test did not provide reliable results in determining clopidogrel resistance.

Endovascular Treatment in Patients with Cerebral Artery Occlusion of Three Different Etiologies

Background and Purpose

The outcome of endovascular treatment (EVT) may differ depending on the etiology of arterial occlusion. This study aimed to assess the differences in EVT outcomes in patients with intracranial arterial steno-occlusion (ICAS-O), artery-to-artery embolism (AT-O), and cardiac embolism (CA-O).

Methods

We retrospectively analyzed 330 patients with ischemic stroke who underwent EVT between January 2012 and August 2017. Patients were classified according to the etiology. The clinical data, EVT-related factors, and clinical outcomes were compared. The modified Rankin Scale (mRS) score at 3 months, determined using ordinal logistic regression (shift analysis), was the primary outcome.

Results

CA-O (n=149) was the most common etiology, followed by ICAS-O (n=63) and AT-O (n=49). Age, initial National Institutes of Health Stroke Scale (NIHSS) score, and rate of hemorrhagic transformation were significantly higher in patients with CA-O compared to AT-O and ICAS-O. The time from onset-to-recanalization was the shortest in the CA-O (356.0 minutes) groups, followed by the AT-O (847.0 minutes) and ICAS-O (944.0 minutes) groups. The rates of successful recanalization, mRS distribution, and favorable outcomes at 3 months (mRS 0–2; CA-O, 36.9%, AT-O, 53.1%; and ICAS-O, 41.3%) did not differ among the three groups. Baseline NIHSS score (odds ratio, 0.87; 95% confidence interval, 0.83 to 0.91) could independently predict a favorable shift in mRS distribution.

Conclusions

The functional outcomes of ICAS-O and AT-O were similar to those of CA-O, despite the delay in symptom onset-to-recanalization, suggesting that the therapeutic time window may be extended in these patients.

Successful Retrieval of the Distal Anti-embolic Device after Carotid Stenting Using the Balloon Bridge Technique

Background

During carotid artery stenting (CAS), retrieval of the distal umbrella portion of the anti-embolic device (AED) could be difficult. Herein, we report a case of left CAS managed with balloon angioplasty and stent placement with successful retrieval of the umbrella portion of the AED using the balloon bridge technique after failure of retrieval with the standard technique.

Case Presentation

After successful revascularization of the asymptomatic severe carotid bulb stenosis in a 62-year-old woman, we could not pass the re-sheathing catheter over the deployed stent because of the ledge effect between the guidewire of the AED and the stent mesh. However, using the balloon bridge technique, which helped minimize the ledge effect, we could advance the guiding catheter beyond the stented segment over the partially inflated balloon. The umbrella portion of the AED could be easily retrieved through the guiding catheter without complications.

Conclusion

During CAS, the balloon bridge technique could be used to retrieve the AED after failure of retrieval with the standard techniques.

International Survey on Criteria for Training and Accreditation in Interventional Neuroradiology

Purpose

With the rapid expansion of the field of interventional neuroradiology (INR) and the diverse background of aspiring neuro-interventionists, there is an ever increasing need to establish consensus criteria for training and accreditation in INR.

Materials and Methods

We performed a survey to explore the current state of criteria for training and accreditation in INR. The questionnaire consisting of 11 questions was emailed to the members of World Federation of Interventional and Therapeutic Neuroradiology (WFITN) worldwide. It was focused on the training charter, training program, qualifying examination, and education after training program as perceived by practitioners in each country.

Results

A total of 52 WFITN members in 19 countries responded to the questionnaire. There was a huge variation internationally and nationally due to the unique situation and challenges in each country and institution. Criteria for training and accreditation in INR were well established in some countries of Europe, North America, and Asia but not specified in other countries.

Conclusion

It is critical to establish consensus criteria for training and accreditation in INR in order to ensure safe practice and continued expansion and development of INR as a specialty.

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.

Current Status of Clinical Diagnosis and Genetic Analysis of Hereditary Hemorrhagic Telangiectasia in South Korea: Multicenter Case Series and a Systematic Review

Purpose

Hereditary hemorrhagic telangiectasia (HHT), a rare genetic vascular disorder, has been rarely reported in South Korea. We investigated the current prevalence and presenting patterns of genetically confirmed HHT in South Korea.

Materials and Methods

We defined HHT patients as those with proven mutations on known HHT-related genes (ENG, ACVRL1, SMAD4, and GDF2) or those fulfilling 3 or 4 of the Curaçao criteria. A computerized systematic search was performed in PubMed and KoreaMed using the following search term: (“hereditary hemorrhagic telangiectasia” AND “Korea”) OR (“Osler-Weber-Rendu” AND “Korea”). We also collected government health insurance data. HHT genetic testing results were collected from three tertiary hospitals in which the genetic tests were performed. We integrated patient data by analyzing each case to obtain the prevalence and presenting pattern of HHT in South Korea.

Results

We extracted 90 cases from 52 relevant articles from PubMed and KoreaMed. An additional 22 cases were identified from the three Korean tertiary hospitals after excluding seven cases that overlapped with those in the published articles. Finally, 112 HHT patients were identified (41 males and 71 females, aged 4–82 years [mean±standard deviation, 45.3±20.6 years]). The prevalence of HHT in South Korea is about 1 in 500,000, with an almost equal prevalence among men and women. Forty-nine patients underwent genetic testing, of whom 28 had HHT1 (ENG mutation) and 19 had HHT2 (ACVRL1 mutation); the other two patients were negative for ENG, ACVRL1, and SMAD4 mutations.

Conclusion

The prevalence of HHT is underestimated in Korea. The rate of phenotypic presentation seems to be similar to that found worldwide. Korean health insurance coverage is limited to representative genetic analysis to detect ENG and ACVRL1 mutations. Further genetic analyses to detect HHT3, HHT4, and other forms of HHT should be implemented.

Cigarette Smoking Preferentially Affects Intracranial Vessels in Young Males: A Propensity-Score Matching Analysis

Purpose

Cigarette smoking (CS) is one of the major risk factors of cerebral atherosclerotic disease, however, its level of contribution to extracranial and intracranial atherosclerotic stenosis (ECAS and ICAS) was not fully revealed yet. The purpose of our study was to assess the association of CS to cerebral atherosclerosis along with other risk factors.

Materials and Methods

All consecutive patients who were angiographically confirmed with severe symptomatic cerebral atherosclerotic disease between January 2002 and December 2012 were included in this study. Multivariate logistic regression analyses were performed to identify risk factors for ECAS and ICAS. Thereafter, CS group were compared to non-CS group in the entire study population and in a propensity-score matched population with two different age-subgroups.

Results

Of 1709 enrolled patients, 794 (46.5%) had extracranial (EC) lesions and the other 915 (53.5%) had intracranial (IC) lesions. CS group had more EC lesions (55.8% vs. 35.3%, P<0.001) whereas young age group (<50 years) had more IC lesion (84.5% vs. 47.6%, P<0.001). In multivariate analysis, seven variables including CS, male, old age, coronary heart disease, higher erythrocyte sedimentation rate, multiple lesions, and anterior lesion were independently associated with ECAS. In the propensity-score matched CS group had significant more EC lesion compared to non-CS group (65.7% vs. 47.9%) only in the old age subgroup.

Conclusion

In contrast to a significant association between CS and severe symptomatic ECAS shown in old population, young patients did not show this association and showed relatively higher preference of ICAS.

DWI-pc-ASPECT score in basilar artery occlusion: is 6 points or less always indicative of a bad outcome?

BACKGROUND AND PURPOSE

The prognosis of patients with acute basilar arterial occlusion after endovascular reperfusion therapy with diffusion-weighted imaging - posterior circulation-Alberta Stroke Program Early Computed Tomography Score (DWI-pc-ASPECTS) of 6 or less remains unclear. We aimed to assess the characteristics and prognosis of endovascular reperfusion therapy in patients with acute basilar arterial occlusion and DWI-pc-ASPECTS of 6 or less.

METHODS

We analysed data collected from 1 January 2012 to 31 January 2018 in a prospective neuro-interventional registry of consecutive patients treated with endovascular reperfusion therapy. Clinical and imaging data on patients with DWI-pc-ASPECTS of 6 or less who underwent endovascular reperfusion therapy for acute basilar arterial occlusion were collected for this study. A good clinical outcome was defined as a modified Rankin scale of 2 or less at 90 days.

RESULTS

Forty-five acute basilar arterial occlusion patients with DWI-pc-ASPECTS of 6 or less were included. Among them, 11 (24.4%) patients had a good clinical outcome at 90 days. Patients with a good clinical outcome had less severe neurological symptoms at presentation (National Institutes of Health Stroke Scale (NIHSS) 19.0 (12.0-25.0) vs. 8.0 (6.0-11.5); P = 0.003) and were younger (72.5 years (57.0-80.0 years) vs. 63.0 years (55.5-69.0 years), P = 0.096) than those with a poor clinical outcome. The symptomatic intracranial haemorrhage rate was significantly higher in the poor clinical outcome group (13 (38.2%)) than in the good clinical outcome group (0 (0.0%)) (P = 0.045). In particular, in patients aged over 70 years, a favourable outcome was low (18 (52.9%) vs. 1 (9.1%); P = 0.027) even after successful recanalisation. In a multivariate model, a low initial NIHSS score (odds ratio 1.21; 95% confidence interval 1.07-1.44; P = 0.0093) and age over 70 years (odds ratio 15.27; 95% confidence interval 1.85-379.79; P = 0.0321) were independent predictors of poor clinical outcome.

CONCLUSIONS

Even with DWI-pc-ASPECTS of 6 or less, good clinical outcome can be achieved after endovascular reperfusion therapy. Relatively mild initial symptoms and younger age can predict a better outcome in acute basilar arterial occlusion patients with DWI-pc-ASPECTS of 6 or less.

Osseous versus Nonosseous Spinal Epidural Arteriovenous Fistulas: Experiences of 13 Patients

BACKGROUND AND PURPOSE

Spinal epidural arteriovenous fistulas are rare vascular malformations. We present 13 patients with spinal epidural arteriovenous fistulas, noting the various presenting symptom patterns, imaging findings related to bone involvement, and outcomes.

MATERIALS AND METHODS

Among 111 patients with spinal vascular malformations in the institutional data base from 1993 to 2017, thirteen patients (11.7%) had spinal epidural arteriovenous fistulas. We evaluated presenting symptoms and imaging findings, including bone involvement and mode of treatment. To assess the treatment outcome, we compared initial and follow-up clinical status using the modified Aminoff and Logue Scale of Disability and the modified Rankin Scale.

RESULTS

The presenting symptoms were lower back pain (n = 2), radiculopathy (n = 5), and myelopathy (n = 7). There is overlap of symptoms in 1 patient (No. 11). Distribution of spinal epidural arteriovenous fistulas was cervical (n = 3), thoracic (n = 2), lumbar (n = 6), and sacral (n = 2). Intradural venous reflux was identified in 7 patients with congestive venous myelopathy. The fistulas were successfully treated in all patients who underwent treatment (endovascular embolization, n = 10; operation, n = 1) except 2 patients who refused treatment due to tolerable symptoms. Transarterial glue (n = 7) was used in nonosseous types; and transvenous coils (n = 3), in osseous type. After 19 months of median follow-up, the patients showed symptom improvement after treatment.

CONCLUSIONS

Although presenting symptoms were diverse, myelopathy caused by intradural venous reflux was the main target of treatment. Endovascular treatment was considered via an arterial approach in nonosseous types and via a venous approach in osseous types.

Cannulation of Occluded Inferior Petrosal Sinuses for the Transvenous Embolization of Cavernous Sinus Dural Arteriovenous Fistulas: Usefulness of a Frontier-Wire Probing Technique

BACKGROUND AND PURPOSE

Pursuing an alternative access route for transvenous embolization of cavernous sinus dural arteriovenous fistulas can be challenging in patients with an occluded inferior petrosal sinus. We found that cannulation of even a completely occluded inferior petrosal sinus is feasible, especially when using a standard hydrophilic-polymer-jacketed 0.035-inch guidewire as a frontier-wire for probing.

MATERIALS AND METHODS

From 2002 to 2017, the frontier-wire technique was tried in 52 patients with occluded inferior petrosal sinuses for transvenous embolization of cavernous sinus dural arteriovenous fistulas at our center. Technical success was defined as access into the affected cavernous sinus compartment with a microcatheter through the occluded inferior petrosal sinus and deployment of at least 1 coil. The complications and treatment outcomes were analyzed.

RESULTS

The frontier-wire technique was applied in 52 patients with 57 occluded inferior petrosal sinuses (52 ipsilateral and 5 contralateral inferior petrosal sinuses). Technical success rates were 80.8% (42/52) of patients and 73.7% (42/57) of inferior petrosal sinuses. Alternative transvenous routes were used in 3 patients, and transarterial access was used in 7 patients. Complete embolization of fistulas was achieved in 82.2% (37/45) of patients in the transvenous embolization group and in 14.3% (1/7) of patients in the transarterial group. No procedure-related morbidity or mortality was observed.

CONCLUSIONS

Transvenous embolization of cavernous sinus dural arteriovenous fistulas, even through a completely occluded inferior petrosal sinus, is feasible. The difficulty of passing the microcatheter can be minimized by prior probing of the occluded inferior petrosal sinus using a standard 0.035-inch guidewire; the trace of the guidewire on the roadmap image serves as a guide for microcatheter navigation through the inferior petrosal sinus on fluoroscopy.

Loop microcatheter technique for coil embolization of paraclinoid aneurysms

BACKGROUND

Although paraclinoid aneurysms do not exhibit a high risk of rupture, coil embolization is not always easy because of unstable microcatheter position. We present a technique that allows a stable microcatheter position for coil embolization of paraclinoid aneurysms.

METHODS

We enrolled 34 consecutive patients who underwent coil embolization for paraclinoid aneurysms. A loop of distal microcatheter was shaped based on three-dimensional rotational angiography. The basic concept is to keep the proximal loop abutting the opposite wall of the aneurysm while using the distal loop for coiling. Then, a proximal curve was made to accommodate the shape of the carotid siphon, which may decide the direction of the loop. Stent-assisted coil embolization was performed in 19 wide-necked aneurysms. Immediate radiological outcomes were analyzed with Raymond classification and clinical outcomes were evaluated with modified Rankin Scale (mRS) scores.

RESULTS

Satisfactory occlusion of aneurysm was achieved in 94.1% (32/34) of patients with a Raymond score of 1 or 2. Packing density of ≥ 31% was achieved in 71% (24/34) of patients. No significant differences were observed between stent-assisted coiling and coiling-only groups. Follow-up magnetic resonance angiography and/or angiogram showed stable coil position, except in one patient with tiny recurrence (from Raymond scores 1 to 2) that did not require retreatment at the 6-month follow-up. mRS scores of 0-1 were obtained in all patients at 6 months.

CONCLUSIONS

Loop microcatheter technique allowed safe and stable coil packing for paraclinoid aneurysms. The same procedural concept is also being used for aneurysms in other vascular territories.

Low-Dose Prasugrel in Patients with Resistance to Clopidogrel for the Treatment of Cerebral Aneurysms

Thromboembolism is one of the major complications of stent assisted coiling in treatment of cerebral aneurysm. Clopidogrel resistance is so common and prasugrel is more effective in its rapid and potent effect. We investigated changes in the value of P2Y12 resistance unit (PRU) when prasugrel was administered to patients with clopidogrel resistance. One hundred mg of aspirin and 75 mg of clopidogrel were administered for 5 days before the procedure, and PRU were examined. The resistance to clopidogrel was defined as the inhibition of PRU was less than 20%. PRU was re-examined after loading 20 mg of prasugrel. We treated 98 consecutive patients between January 2018 and July 2018, and 24 patients (24.5%) had resistance to clopidogrel. Nineteen patients were female. The mean PRU value at admission was 238.5±36.9 and the percentage inhibition value was 4.8±6.3%. After the use of prasugrel, the mean PRU and percentage inhibition values were measured as 124.9±49.9 and 48.0±19.24, respectively. All patients except one patient had a PRU inhibition value as a responder. There was no hemorrhage or thromboembolic complication during mean 1.5 months follow-up after embolization procedure. In conclusion, in patients resistant to clopidogrel, the low dose prasugrel seems to be effective in keeping the percentage inhibition value of PRU within the normal range in treatment of cerebral aneurysm. Further study will be needed to determine the optimal dose of prasugrel to enhance prevention effect of thromboembolism and to reduce hemorrhagic complications during stent assisted coiling.

Diagnosis of Cerebral Aneurysm Via Magnetic Resonance Angiography Screening: Emphasis on Legal Responsibility Increases False Positive Rate

Purpose

False positive diagnoses of cerebral aneurysm via magnetic resonance angiography (MRA) screening may increase unnecessary cerebral catheter angiography. The purpose of this study was to investigate the effects of medical liability on medical decision-making during radiologic interpretation.

Materials and Methods

We included 56 consecutive patients who were referred with suspected aneurysm based on MRA or computed tomography angiography (CTA) and showed no aneurysm on subsequent digital subtraction angiography (DSA). MRA and CTA were reviewed twice by two neuroradiology fellows who were blind as to whether the suspected lesions were true aneurysms or not. The second review was repeated after proposing that their decision was subject to legal liability and they would be responsible for medico-legal problems related to their diagnoses. Diagnostic differences based on each review were analyzed, focusing on changes in false positive diagnosis rates.

Results

A total of 63 suspected aneurysmal lesions detected via MRA or CTA were found to be negative based on DSA. At first review, 32 lesions were diagnosed as true aneurysms by observer 1 and 27 by observer 2, corresponding to false positive rates of 51% and 43% respectively. At the second review, 39 lesions (62%) were diagnosed by observer 1, and 30 (48%) by observer 2. Thus, there was an overall increase in false positive aneurysm diagnosis of 11% for observer 1 and 5% for observer 2, after emphasizing their responsibilities in the context of medical litigation.

Conclusion

Concerns about medical liability could result in increased false positive diagnoses of cerebral aneurysms via MRA screening. Whether repeated follow-up of the suspected lesion or catheter angiographic confirmation is better with regard to long-term patient outcomes requires further study.

Adjuvant Coil Assisted Glue Embolization of Vein of Galen Aneurysmal Malformation in Pediatric Patients

Purpose

Adjuvant coils may offer advantages in flow control during glue embolization of high flow vein of Galen aneurysmal malformation (VGAM) patients but involves specific issues such as feasibility, durability and coil mass effect. The purpose of this study is to assess the outcome of adjuvant coils in addition to transarterial glue embolization for treatment of these patients.

Materials and Methods

Five pediatric VGAM patients (age range; 11 weeks to 2 yrs 2 mos) with high flow fistulous angioarchitecture were treated with adjuvant coils 1) in the distal feeding artery and/or 2) in the vein of Galen followed by glue embolization of the shunt. The angiographic / clinical outcomes were assessed.

Results

Adjuvant coils were deployed in the distal feeding artery (n=3), vein of Galen pouch plus distal feeding artery (n=2). Additional transarterial glue embolization of the fistulae was successfully performed (n=4). Complete occlusion was achieved with coils in one case. Complete occlusion was achieved for all mural type cases (n=4). Residual feeders remained in a case of choroidal type of VGAM. No complications were noted related to the treatment. All patients showed normal development on follow up (range: 7.6 to 88.8 mo, mean 49.3 mo). Initial hydrocephalus improved on follow up despite coil mass effect in dilated vein of Galen.

Conclusion

Adjuvant coils for flow control with glue embolization may be a safe and effective treatment method for VGAM patients with high flow fistulous feeders.

Development of New Endovascular Devices for Aneurysm Treatment

Since the first use of the Guglielmi detachable coil system for cerebral aneurysm embolization in 1990, various endovascular methods have been developed to treat large numbers of aneurysms. The main strategic and technical modifications introduced to date include balloon-assisted coil embolization, stent-assisted coil embolization, flow diverters, and flow disrupters. The development and introduction of such devices have been so persistent and rapid that new devices are being approved worldwide even before the earlier ones become available in some countries. However, even if some patient populations may possibly benefit from earlier introduction of new devices, the approval authorities should balance the available evidence of the safety and effectiveness of novel devices. This review aims to provide an overview of the recent innovations in endovascular treatment of cerebral aneurysms and a brief review of market access policies and regulations for importing high-risk medical devices, such as those used for endovascular aneurysm management, which correspond to class III devices, as defined by the U.S. Food and Drug Administration. We focus on the current situation in Korea and compare it with that in other Asian countries, such as China and Japan.

A new retrieval method for an already detached coil mass in the aneurysm sac: 'Thread and catch' technique

During endovascular coiling, unexpected procedure-related complications such as coil misplacement have been reported, and these complications may induce emboli or thrombotic vessel occlusion. A malpositioned detached coil contained and immobilized within an intracranial aneurysm is difficult to remove using current methods. We report an effective retrieval technique for detached coils. The 'thread and catch technique' can be used when the malpositioned detached coil is immobilized within the aneurysm.

Visualization of Soft Tissue Venous Malformations of Head and Neck with 4D Flow Magnetic Resonance Imaging

Evaluation of hemodynamics in venous malformation (VM) in the head and neck area is done by direct puncture venography before alcohol sclerotherapy, but it is difficult due to a variable degree of filling in from the artery and filling out into the draining vein. We present our preliminary experience of 4D MRI to evaluate VM hemodynamics. Four patients with venous malformation in the maxillofacial area underwent both 4D MRI and direct puncture venography before alcohol sclerotherapy. To find out appropriate velocity encoding (VENC) for VM, we applied 5-50 cm/sec VENC. Significant high-flow foci demonstrated by phase changes in magnitude images were compared with lesion types shown on a direct puncture venogram. Detection of flow in VM was possible in magnitude images or phase-difference images when VENC was set to less than 30 cm/sec. Appropriate VENC for VM was regarded as less than 5 cm/sec. High-flow areas in the dilated venous sac demonstrated focal spots or linear band-like areas on phase changes of 4D MRI. Appropriate VENC application was mandatory to detect flow in VM. Flow information on 4D MRI provided flow information in VM which was not detected on a direct puncture venogram in the compartmentalized lesion and thus can make alcohol sclerotherapy safer.

Evaluation of cerebral blood flow change after cigarette smoking using quantitative MRA

BACKGROUND AND OBJECTIVE

Changes in cerebral blood flow (CBF) immediately after cigarette smoking (CS) are still unclear. Our purpose was to evaluate the hemodynamic changes in each intracranial vessel after CS by using quantitative magnetic resonance angiography (MRA).

MATERIAL AND METHODS

Fifteen healthy male smokers less than 45 years old with more than 3 pack-year smoking history were enrolled in this study. The hemodynamic change in the vessels, represented by cerebral flow rate (CFR, ml/s) and flow velocity (FV, cm/s), was quantitatively measured in eleven vascular segments of the brain using phase-contrast MRA. Two sets of data at each vessel before and after CS were statistically analyzed by paired t-test. Three of 15 participants, as a control group, followed all the procedures but did not smoke.

RESULTS

Total CFR of the distal intracranial vessels (anterior, middle, and posterior cerebral arteries; ACA, MCA, and PCA) was significantly reduced after CS by 7.3% (847 vs. 785 ml/s, p = 0.024). Such flow changes were statistically more significant in the anterior circulation (ACA and MCA) compared to the posterior circulation (PCA). All distal intracranial vessels did not have significant FV change while peak systolic velocity and mean velocity dropped 7.4 and 4.3% and pulsatility index decreased 10.9% in the internal carotid artery. Regarding cross-sectional areas, all distal intracranial vessels showed diminished, and only MCA had a statistical significance (9.9 vs. 9.3 mm2, p = 0.016).

CONCLUSIONS

There was a significant decrease of CFR after CS especially in the anterior circulation of twelve young male smokers. Considering the changes of FV and cross-sectional area all together, it can be suggested that cerebrovascular impedance increased after CS especially at the main trunk level of the distal intracranial vessels (ACA, MCA, and PCA).

Subacute endovascular recanalization of symptomatic cerebral artery occlusion: a propensity score-matched analysis

BACKGROUND

The interval between the onset of cerebral vessel occlusion and recanalization has been shown to be an independent predictor of poor outcomes. However, endovascular recanalization of symptomatic cerebral vessel occlusion in the subacute period has not been well documented. We investigated the safety and efficacy of subacute recanalization of occluded cerebral vessels in patients with ischemic stroke or transient ischemic attacks (TIAs).

METHODS

Between 2014 and 2015, 98 patients were admitted to the emergency room for ischemic stroke or TIA with a small infarct core, which was defined as modest early ischemic change on non-contrast CT or overt diffusion-perfusion mismatch. All patients underwent pre-transfemoral cerebral angiography and post-endovascular treatment. The patients were classified according to acute (onset-to-groin puncture time ≤6 hours) or subacute (onset-to-groin puncture time >6 hours) recanalization. Using propensity score analysis, recipients of acute and subacute recanalization underwent 1:1 matching.

RESULTS

Following 1:1 propensity score matching, 32 patients who underwent acute and 32 who underwent subacute intra-arterial thrombolysis were matched. There were no significant differences in National Institutes of Health Stroke Scale at discharge, modified Rankin scale (mRS), the proportion of patients with an mRS value of 0-2, mortality at discharge, intracerebral bleeding, postprocedural infarct extension, newly detected infarction, and hyperintense acute reperfusion marker on follow-up images between the acute and subacute recanalization groups.

CONCLUSIONS

In selected patients with clinically unstable cerebral artery occlusions, a diffusion-perfusion mismatch and small CT lesions, subacute and acute recanalization has comparable safety and efficacy rates.

Angiographic and clinical outcomes of balloon remodeling versus unassisted coil embolization in the ruptured aneurysm cohort of the GEL THE NEC study

BACKGROUND AND PURPOSE

GEL THE NEC (GTN) was a multicenter prospective registry developed to assess the safety and efficacy of HydroSoft coils in treating intracranial aneurysms. We compared the angiographic and clinical outcomes of aneurysms treated with balloon assisted coil embolization (BACE) versus unassisted coil embolization (CE) in the ruptured aneurysm cohort.

MATERIALS AND METHODS

GTN was performed at 27 centers in five countries. Patients aged 21-90 years with a ruptured aneurysm 3-15 mm in size were eligible for enrollment. We analyzed demographics/comorbidities, aneurysm location, and geometry, including maximum diameter, neck size, and dome to neck ratio, immediate and long term angiographic outcomes (graded by an independent core laboratory using the modified Raymond Scale), and procedure related adverse events. Angiographic and clinical outcomes were studied using χ²and t tests.

RESULTS

Of the 599 patients in the GTN, 194 met the inclusion criteria. 84 were treated with BACE and 110 with CE. There were more prior smokers in the BACE group (p=0.01). The BACE group also had more vertebrobasilar aneurysms (p=0.006) and a larger mean neck size (p=0.02). More aneurysms were immediately completely occluded in the BACE group (p=0.02) Procedure- related major morbidity and mortality were no different between the techniques (p=0.4 and p=1, respectively).

CONCLUSIONS

In this prospective ruptured aneurysm cohort from the GTN, BACE resulted in greater occlusion rates compared with unassisted CE with similar morbi-mortality.

Endovascular management of aneurysms associated with spinal arteriovenous malformations

Background

Spinal aneurysms are rare among spinal arteriovenous malformations (SAVMs). There are few reports of endovascular management of spinal aneurysms associated with SAVM.

Objective

To present endovascular management of aneurysms associated with SAVM.

Methods

Of 91 patients with SAVMs,eight (9%) presented with aneurysms. Of these, three were male and five were female with a median age of 18 years (range 11–38). We evaluated the presenting pattern, lesion level, type of the target aneurysm related to the presenting pattern and AVM nidus, and the result obtained after embolization or open surgery. Clinical status was evaluated by Aminoff–Logue (ALS) gait and micturition scale scores.

Results

The presenting patterns were subarachnoid hemorrhage (SAH, n=3) or mass effect caused by extrinsic (n=4) or intrinsic (n=1) cord compression. Aneurysms were located in four cervical, two thoracic, and two lumbar enlargement areas. There were two prenidal (arterial), three nidal, and three postnidal (venous) aneurysms. The mean diameter of the aneurysms was 9 mm (range 3–27). Glue embolization (n=6), open surgery (n=1), and combined surgery and embolization (n=1) was performed to obliterate the aneurysms. Obliteration of the target aneurysms resulted in improvement of symptoms and clinical stabilization of SAVMs in all patients during a mean of 55 months (range 7–228) of follow-up.

Conclusions

Identification of a symptomatic aneurysm should be associated with clinical presentation pattern. Targeted obliteration of the aneurysm by embolization and/or surgery resulted in improvement of symptoms and stabilization of SAVM.

Multidisciplinary Approach to Decrease In-Hospital Delay for Stroke Thrombolysis

Background and Purpose

Decreasing the time delay for thrombolysis, including intravenous thrombolysis (IVT) with tissue plasminogen activator and intra-arterial thrombectomy (IAT), is critical for decreasing the morbidity and mortality of patients experiencing acute stroke. We aimed to decrease the in-hospital delay for both IVT and IAT through a multidisciplinary approach that is feasible 24 h/day.

Methods

We implemented the Stroke Alert Team (SAT) on May 2, 2016, which introduced hospital-initiated ambulance prenotification and reorganized in-hospital processes. We compared the patient characteristics, time for each step of the evaluation and thrombolysis, thrombolysis rate, and post-thrombolysis intracranial hemorrhage from January 2014 to August 2016.

Results

A total of 245 patients received thrombolysis (198 before SAT; 47 after SAT). The median door-to-CT, door-to-MRI, and door-to-laboratory times decreased to 13 min, 37.5 min, and 8 min, respectively, after SAT implementation (P<0.001). The median door-to-IVT time decreased from 46 min (interquartile range [IQR] 36–57 min) to 20.5 min (IQR 15.8–32.5 min; P<0.001). The median door-to-IAT time decreased from 156 min (IQR 124.5–212.5 min) to 86.5 min (IQR 67.5–102.3 min; P<0.001). The thrombolysis rate increased from 9.8% (198/2,012) to 15.8% (47/297; P=0.002), and the post-thrombolysis radiological intracranial hemorrhage rate decreased from 12.6% (25/198) to 2.1% (1/47; P=0.035).

Conclusions

SAT significantly decreased the in-hospital delay for thrombolysis, increased thrombolysis rate, and decreased post-thrombolysis intracranial hemorrhage. Time benefits of SAT were observed for both IVT and IAT and during office hours and after-hours.

Preoperative embolization in patients with metastatic spinal cord compression: mandatory or optional?

Background

The contribution of preoperative embolization in reducing intraoperative blood loss and its clinical importance are unclear. So, we aimed to compare the perioperative clinical outcomes based on whether preoperative embolization was performed and assess the role and safety of preoperative embolization in metastatic spinal cord compression (MSCC) patients.

Methods

We enrolled 52 patients (men, 37; women, 15) who underwent palliative decompression for MSCC. Demographic data, neurologic status, surgery-related data (operation time, estimated blood loss, and transfusion), complications, and survival time were recorded. Patients were categorized based on whether they received preoperative embolization: groups E (embolization) (n = 18) and NE (non-embolization) (n = 34) and the clinical parameters were compared. Subgroup analysis was performed specifically for cases of hypervascular tumors (23/52, 44%).

Results

The transfusion degree was greater in the NE group (4.6 pints) than in the E group (2.5 pints, P = 0.025); the other parameters did not differ between the groups. However, massive bleeding (>2000 mL) was more frequent in the NE group (10/34) than in the E group (0/18, P = 0.010). Subgroup analysis indicated that intraoperative blood loss was greater in the NE group (1988 mL) than in the E group (1095 mL, P = 0.042) in hypervascular tumor patients. Although massive bleeding was more frequent among hypervascular tumor patients, 3 patients with non-hypervascularized tumors also exhibited massive bleeding (P = 0.087).

Conclusions

Intraoperative blood loss and perioperative transfusion can be reduced by preoperative embolization in MSCC patients. Neurologic recovery, operation time, and complications did not differ according to the application of embolization. As preoperative embolization is relatively safe and effective for controlling intraoperative bleeding without any neurologic deterioration, it is highly recommended for hypervascular tumors. Moreover, it may also be effective for non-hypervascular tumors as massive bleeding may be noted in some cases.