Identification of potential biomarkers associated with meat tenderness in Hanwoo (Korean cattle): An expression quantitative trait loci analysis.

Meat tenderness is considered the most important trait contributing to beef quality, level of consumer satisfaction, willingness to pay premium prices and industry profit. Genomic selection method would be helpful for genetic improvement of traits with low heritability and that are difficult to measure. The identification of core genes can aid genomic selection for complex traits with low heritability that are difficult to measure. We performed statistical analysis of associations between longissimus dorsi muscle tenderness and gene expression in 20 Hanwoo cattle, using Warner-Bratzler shear force and RNAseq data, respectively. We found a total of 166 core genes, from which six (ASAP1, CAPN5, ELN, SUMF2, TTC8 and MGAT4A) were regulated by 16 cis-expression quantitative trait loci (eQTL) SNPs. Notably, we found that a cis-eQTL SNP of the ELN gene contained an MFZ-1 binding site in its putative promoter region. These findings provide useful information for genomic prediction of beef tenderness in Hanwoo cattle.

Role of Apparent Diffusion Coefficient Gradient Within Diffusion Lesions in Outcomes of Large Stroke After Thrombectomy.

BACKGROUND AND PURPOSE: The outcome of endovascular treatment in stroke patients with a large ischemic core is not always satisfactory. We evaluated whether the severity of baseline diffusion-weighted imaging abnormalities, as assessed by different apparent diffusion coefficient (ADC) thresholds, correlates with the clinical outcome in these patients after successful endovascular treatment. METHODS: In 82 consecutive patients with a large vessel occlusion in the anterior circulation admitted ≤24 hours after onset, a baseline diffusion lesion volume (ADC ≤620×10-6 mm2/s [ADC620]) ≥50 mL and successful recanalization by endovascular treatment were retrospectively investigated. Lesion volumes of 3 ADC thresholds (ADC620, ADC ≤520×10-6 mm2/s [ADC520], and ADC ≤540×10-6 mm2/s [ADC540]) were measured using an automated Olea software program. The performance of the ADC520/ADC620 and ADC540/ADC620 ratios in predicting the functional outcome was assessed by receiver operating characteristic curve analysis. The ADC ratio with optimal threshold showing better receiver operating characteristic performance was dichotomized at its median value into low versus high subgroup and its association with the outcome subsequently evaluated in a multivariable logistic regression model. RESULTS: The median baseline diffusion lesion volume was 80.8 mL (interquartile range, 64.4-105.4). A good functional outcome (modified Rankin Scale score, ≤2) was achieved in 35 patients (42.7%). The optimal threshold for predicting the functional outcome was identified as ADC540/ADC620 (area under the curve, 0.833) and dichotomized at 0.674. After adjusting for age, baseline National Institutes of Health Stroke Scale score, intravenous tissue-type plasminogen activator, baseline diffusion lesion volume, and onset-to-recanalization time, a low ADC540/ADC620 was independently associated with a good functional outcome (adjusted odds ratio, 10.72 [95% CI, 3.06-37.50]; P<0.001). CONCLUSIONS: A low ADC540/ADC620, which may reflect less severe ischemic stress inside a diffusion lesion, may help to identify patients who would benefit from endovascular treatment despite having a large ischemic core.

Usefulness of combination usage of balloon guide catheter with contact aspiration thrombectomy.

BACKGROUND: Angiographic outcomes of contact aspiration thrombectomy (CAT), a frontline thrombectomy strategy, can vary depending on balloon guide catheter (BGC) usage, stroke etiology, and occlusion location. The purpose of this study was to analyze conditional outcomes of CAT to determine which result in maximum angiographic benefits. METHODS: Patients who received CAT for anterior circulation occlusive stroke between January 2017 and December 2018 were included. Angiographic and clinical outcomes were compared relative to BGC use, stroke etiology, and occlusion location. Multivariable analyses for first-pass reperfusion (FPR) and favorable clinical outcome were performed. RESULTS: Of 160 included patients, the rates of FPR, successful reperfusion after CAT, final successful reperfusion, and favorable clinical outcome were 43.1%, 58.1%, 81.9%, and 60.6%, respectively. BGC use was associated with a higher rate of FPR, successful reperfusion after CAT, a lower rate of distal embolization, and faster reperfusion. Based on subgroup analysis, BGC usage in ICA, MCA M1 occlusion, and cardioembolism were associated with higher FPR, successful reperfusion after CAT, and lower distal embolization. Faster reperfusion was achieved in ICA occlusions and cardioembolisms. BGC usage was an independent predictor of FPR. Favorable clinical outcome was associated with male gender, low initial NIHSS score, fast onset to reperfusion, and FPR. CONCLUSIONS: In CAT, BGC usage was associated with better angiographic outcomes, including higher FPR, successful reperfusion after CAT, prevention of distal embolization, and faster reperfusion, especially in proximal occlusions and cardioembolisms. These conditions may play a role in maximizing the benefits of CAT.

Predicting Endovascular Treatment Outcomes in Acute Vertebrobasilar Artery Occlusion: A Model to Aid Patient Selection from the ASIAN KR Registry.

Background The decision to perform endovascular treatment (EVT) for stroke related to vertebrobasilar occlusion (VBO) remains controversial. Purpose To identify preprocedural predictors of good outcomes and to develop a model to aid patient selection for VBO. Materials and Methods For this retrospective study using a Korean multicenter registry, a predictive model for good outcomes (modified Rankin scale score, 0-2) was generated based on a derivation sample of patients with VBO (January 2011-February 2016). Preprocedural parameters, including onset-to-puncture time, infarct volume, occlusion type as a surrogate marker of intracranial atherosclerotic stenosis-related occlusion or embolic occlusion (truncal-type occlusion vs branching site occlusion), and collateral status, were analyzed. Continuous variables were dichotomized based on receiver operating characteristic analysis. Multiple logistic regression analysis was performed to generate a predictive model. The model was internally validated with the bootstrap method and was externally validated with a single-center sample (April 2016-December 2018). Results A predictive model was generated from 71 patients (mean age, 67 years ± 11 [standard deviation]; 41 [58%] men) and was externally validated in 32 patients (mean age, 72 years ± 13; 19 [59%] men). The composite of initial DW imaging volume of less than 10 mL (odds ratio [OR], 19.3; 95% confidence interval [CI]: 3.0, 126.4; P = .002), onset-to-puncture time of less than 8 hours (OR, 8.7; 95% CI: 1.8, 42.0; P = .007), and branching-site occlusion (OR, 6.1; 95% CI: 1.5, 26.0; P = .01) could be used to predict good outcomes, with a median area under the receiver operating characteristic curve of 0.86 (interquartile range [IQR], 0.77-0.95; bootstrap optimism-corrected C statistic, 0.837) in the derivation sample and 0.78 (IQR, 0.62-0.95) in the validation sample. Results failed to show an association between collateral status and outcome (P = .67). Conclusion When selecting patients with vertebrobasilar occlusion for endovascular treatment, the combination of onset-to-puncture time of less than 8 hours, initial infarct volume of less than 10 mL, and presence of branching-site occlusions is indicative of a good outcome. © RSNA, 2020 Online supplemental material is available for this article.

Local tirofiban infusion for remnant stenosis in large vessel occlusion: tirofiban ASSIST study.

BACKGROUND: Compared with embolic occlusions, intracranial atherosclerotic stenosis (ICAS)-related large vessel occlusions (LVOs) often require rescue treatment following mechanical thrombectomy (MT). Herein, we hypothesized that local tirofiban infusion can be effective and safe for remnant stenosis in LVO during endovascular treatment and can improve clinical outcomes. METHODS: This observational multicenter registry study (January 2011 to February 2016) included patients with ICAS who underwent endovascular treatment for LVO within 24 h after stroke onset. An underlying fixed focal stenosis at the occlusion site observed on cerebral angiography during and after MT was retrospectively determined as a surrogate marker of ICAS. Procedural and clinical outcomes were compared between the tirofiban and non-tirofiban groups. RESULTS: Of 118 patients, 59 received local tirofiban infusion. Compared to the non-tirofiban group, patients were older (non-tirofiban group versus tirofiban group; median, 63 years vs. 71 years, p = 0.015) and the onset-to-puncture time was longer (median, 275 min vs. 395 min, p = 0.036) in the tirofiban group. The median percent of residual stenosis prior to rescue treatment tended to be higher in the tirofiban group (80 [71-86] vs. 83 [79-90], p = 0.056). Final reperfusion success (modified Treatment In Cerebral Ischemic 2b-3) was more frequent (42.4%vs. 86.4%, p = 0.016) and post-procedure parenchymal hematoma type 2 and/or thick subarachnoid hemorrhages were less frequent (15.3%vs. 5.1%, p = 0.068) in the tirofiban group. The frequency of favorable outcomes 3 months after endovascular treatment (modified Rankin Scale 0-2) was significantly higher in the tirofiban group (32.2% vs. 52.5%, p = 0.025), and tirofiban administration was an independent predictor of favorable outcomes (odds ratio, 2.991; 95% confidence interval, 1.011-8.848; p = 0.048). CONCLUSIONS: Local tirofiban infusion can be a feasible adjuvant treatment option for patients with ICAS-LVO.

Immediate effects of first-line thrombectomy devices for intracranial atherosclerosis-related occlusion: stent retriever versus contact aspiration.

BACKGROUND: Although stent retriever (SR) is recommended as a frontline device of endovascular treatment (EVT) for embolic large artery occlusion causing acute ischemic stroke, contact aspiration (CA) device showed similar efficacy in the recent trials. However, the efficacy of the both devices as first-line therapy for intracranial atherosclerotic stenosis (ICAS)-related large vessel occlusion has not yet been established. Therefore, we compared the immediate effects and final outcomes of SR and CA as first-line devices for treating ICAS-related occlusions. METHODS: We retrospectively analyzed the data of patients who underwent EVT for acute ischemic stroke from the registry of three Korean hospitals. Patients with ICAS-related occlusion who were treated within 24 h of onset of the symptoms were included. We investigated immediate reperfusion performance, immediate safety outcomes, and 3-month clinical outcomes for the two first-line devices. RESULTS: Of the 720 registered patients, 111 were eligible for this study. Forty-nine patients (44.1%) used SR and 62 (55.9%) used CA as the first-line device. Achieving successful reperfusion immediately after first-line thrombectomy was more frequent in the SR group than that in the CA group (77.6% vs. 43.5%, p = 0.001), with fewer additional rescue treatments (12.2% vs. 59.7%, p < 0.001). The incidence of iatrogenic dissection or rupture was lower in the SR group than that in the CA group (8.2% vs. 29.0%, p = 0.012). After additional rescue treatments, however, the final successful reperfusion rate did not differ between the two groups (SR 87.8% vs. CA 77.4%, p = 0.247), and there was no significant difference in the 3-month good outcomes (modified Rankin Scale, p = 0.524). CONCLUSIONS: First-line SR thrombectomy showed higher immediate reperfusion and less vessel injury for ICAS-related occlusions than CA. However, there was no significant difference in the final reperfusion status or 3-month outcomes from additional rescue treatments.

A Retrieved Sparganum of Spirometra erinaceieuropaei from a Korean Man during Mechanical Thrombectomy.

Human sparganosis is a zoonotic disease caused by infection and migration of the plerocercoid of Spirometra spp. Although sparganosis were reported from most parts of the body, the sparganum parasitizing inside cerebral artery is remarkably uncommon. We report a case of cerebral intravascular sparganosis in an elderly patient with acute ischemic stroke who was diagnosed by retrieving sparganum during mechanical thrombectomy. Finally, the parasites were identified as Spirometra erinaceieuropaei using multiplex PCR and cox1 gene sequencing.

Ischemic Diffusion Lesion Reversal After Endovascular Treatment.

Background and Purpose- Several studies have reported partial reversal of diffusion-weighted imaging (DWI) lesions after acute stroke reperfusion treatment. However, factors associated with DWI reversal have not yet been systematically investigated. We evaluated the factors associated with DWI reversal after endovascular treatment (EVT). Methods- We retrospectively analyzed consecutively encountered patients with acute ischemic stroke who underwent EVT at 3 comprehensive stroke centers in Korea from January 2011 to February 2016. Patients who received EVT within 24 hours of anterior circulation infarction and had both baseline and follow-up DWIs were included. DWI reversal was defined as a decrease in DWI volume from baseline to follow-up. We compared the characteristics and outcomes between patients with and without DWI reversal and assessed independent factors associated with DWI reversal. Results- Of 720 patients encountered during the time period, 404 patients (56.1%) met the study criteria, with 63 patients (15.5%) showing DWI reversal after EVT. The mean time interval between baseline and follow-up DWI was 4.7±2.4 days. Mean baseline DWI volumes of patients with and without DWI reversal were 30.1±36.7 versus 22.0±30.7 mL ( P=0.106), and follow-up DWI volumes were 17.8±24.9 versus 68.7±77.5 mL ( P<0.001). Patients with DWI reversal showed better functional outcomes at 3 months than those without DWI reversal (modified Rankin Scale [interquartile range], 1 [0-3] versus 2 [1-4]; P=0.001). In a multivariate analysis, complete reperfusion (odds ratio, 1.954; 95% CI, 1.063-3.582) and shorter time from baseline DWI to final reperfusion (odds ratio, 0.991; 95% CI, 0.983-0.998) were independently associated with DWI reversal. Conclusions- Complete reperfusion and shorter imaging time to recanalization were independently associated with DWI reversal among patients with acute ischemic stroke who received EVT.

Balloon Guide Catheter Is Beneficial in Endovascular Treatment Regardless of Mechanical Recanalization Modality.

Background and Purpose- Based on its mechanism, the use of balloon guide catheters (BGCs) may be beneficial during endovascular treatment, regardless of the type of mechanical recanalization modality used-stent retriever thrombectomy or thrombaspiration. We evaluated whether the use of BGCs can be beneficial regardless of the first-line mechanical endovascular modality used. Methods- We retrospectively reviewed consecutive acute stroke patients who underwent stent retriever thrombectomy or thrombaspiration from the prospectively maintained registries of 17 stroke centers nationwide. Patients were assigned to the BGC or non-BGC group based on the use of BGCs during procedures. Endovascular and clinical outcomes were compared between the BGC and non-BGC groups. To adjust the influence of the type of first-line endovascular modality on successful recanalization and favorable outcome, multivariable analyses were also performed. Results- This study included a total of 955 patients. Stent retriever thrombectomy was used as the first-line modality in 526 patients (55.1%) and thrombaspiration in 429 (44.9%). BGC was used in 516 patients (54.0%; 61.2% of stent retriever thrombectomy patients; 45.2% of thrombaspiration patients). The successful recanalization rate was significantly higher in the BGC group compared with the non-BGC group (86.8% versus 74.7%, respectively; P<0.001). Furthermore, the first-pass recanalization rate was more frequent (37.0% versus 14.1%; P<0.001), and the number of device passes was fewer in the BGC group (2.5±1.9 versus 3.3±2.1; P<0.001). The procedural time was also shorter in the BGC group (54.3±27.4 versus 67.6±38.2; P<0.001). The use of BGC was an independent factor for successful recanalization (odds ratio, 2.18; 95% CI, 1.54-3.10; P<0.001) irrespective of the type of first-line endovascular modality used. The use of BGC was also an independent factor for a favorable outcome (odds ratio, 1.40; 95% CI, 1.02-1.92; P=0.038) irrespective of the type of first-line endovascular modality used. Conclusions- Regardless of the first-line mechanical endovascular modality used, the use of BGC in endovascular treatment was beneficial in terms of both recanalization success and functional outcome.

Frontline contact aspiration thrombectomy using SOFIA catheter for acute ischemic stroke: period-to-period comparison with Penumbra catheter.

BACKGROUND: Recent aspiration thrombectomy devices tend to have a more flexible distal tip and larger bore for easy target access and effective reperfusion. Here, this study primarily focused on the efficacy and safety of the SOFIA catheters when it was used as a frontline contact aspiration thrombectomy (CAT) tool for acute intracranial large vessel occlusion in comparison with the data from a period when the Penumbra catheter was used. METHODS: The subjects comprised 189 patients who underwent CAT (90 with Penumbra Max family and 99 with SOFIA/SOFIA plus). Patients' data were retrospectively analyzed to evaluate overall clinical and angiographic outcomes and compared between the devices. RESULTS: Baseline characteristics were similar between groups. But, intravenous alteplase was more frequently administered in the Penumbra group (43.3% vs. 29.3%, p = 0.045), while incidence of ICA occlusion was higher in SOFIA group (18.9% vs. 38.4%, p = 0.013). The modified thrombolysis in cerebral infarction 2b-3 of reperfusion was 94.4% for the Penumbra group and 92.9% for the SOFIA group (p = 0.656). The first-pass effect was more frequently achieved in the SOFIA group (20.0% vs. 39.4%, p = 0.004) and endovascular procedure time was significantly shorter (55.5 min vs. 36 min, p < 0.001). However, clinical outcomes did not differ significantly regarding mortality (11.1% vs. 6.1%, p = 0.213), hemorrhagic complications, and mRS 0-2 at 3 months (63.3% vs. 58.6%; p = 0.504). CONCLUSION: CAT using SOFIA may be safe and comparable to thrombectomy using the Penumbra reperfusion catheter. And, the SOFIA catheter could be advantageous for rapid reperfusion and first-pass effect without any significant complications.

The value of axial loading three dimensional (3D) CT as a substitute for full weightbearing (standing) 3D CT: Comparison of reproducibility according to degree of load.

BACKGROUND: Full weightbearing (WB) three dimensional computed tomography (3D CT) is an excellent imaging tool. However, due to its high cost, it is only used in a few hospitals. We evaluated the usefulness and cost-effectiveness of axial loading (AL) 3D CT by comparing bony alignments with standing radiographs, and assessed reproducibility according to the degree of AL. METHODS: Eighty patients (156 feet), who underwent standing radiographs and 3D CT with an AL device from January 2016 to May 2017, were investigated. According to the degree of AL (AL force×100/body weight), the patients were randomly assigned to three groups: Group A (30-50%; n=21, 40 feet), Group B (50-70%; n=32, 63 feet), and Group C (70-100%; n=27, 53 feet). The following angles were measured three times by two orthopedists: hallux valgus (HVA), 1st-2nd intermetatarsal (IMA1-2), and talo-navicular coverage (TNCA), calcaneal pitch (CPA), talo-1st metatarsal (T1MA), and talo-calcaneal angle (TCA). Agreements between the two imaging methods were analyzed and compared according to the degree of axial loading in each group. RESULTS: Intra- and interobserver reliability was excellent (>0.75). In Group A (30-50% AL), all of the angles except HVA and IMA1-2 differed (p<.05). In Group B (50-70%), TNCA (p=.023), T1MA (p=.017), and TCA (p=.035) differed. In Group C (70-100%), none of the angles differed between the two imaging methods (p>.05). Higher agreement between the two imaging methods was realized when 70% or more(>70%) AL was applied. CONCLUSIONS: AL 3D CT with >70% axial load has full WB effects and can be substituted for expensive full WB 3D CT.

Dorsal suspension for Morton's neuroma: A comparison with neurectomy.

BACKGROUND: The purpose of this study was to investigate and compare the clinical outcomes of dorsal suspension with those of neurectomy for the treatment of Morton's neuroma. METHODS: We conducted a retrospective study of dorsal suspension and neurectomy group. The dorsal suspension was performed by dorsal transposition of neuroma over the dorsal transverse ligament after neurolysis. The visual analog scale (VAS), the Foot and Ankle Ability Measure (FAAM), postoperative satisfaction, and complications were evaluated. RESULTS: Both groups reported significant pain relief, and there were no significant differences between the groups with respect to postoperative pain. The postoperative FAAM outcomes showed no significant between-group differences. Satisfaction analysis showed 'excellent' and 'good' results in the dorsal suspension and neurectomy groups (95% and 77.7%, respectively). Complications of numbness and paresthesia reported in the dorsal suspension group (5% and 5%, respectively) were significantly fewer than those of neurectomy group (61.1% and 33.3%, respectively) (both, p<.05). CONCLUSIONS: With its favorable results, dorsal suspension can be another operative option for the treatment of Morton's neuroma. LEVEL OF EVIDENCE: Level III, retrospective comparative case series.

Efficacy, safety, and clinical outcome of modern mechanical thrombectomy in elderly patients with acute ischemic stroke.

BACKGROUND: The average life expectancy is increasing worldwide, surpassing 80 years in some countries. Recently, mechanical thrombectomy (MT) using modern devices and techniques has led to improved clinical outcomes following acute ischemic stroke. However, thus far, it remains uncertain whether MT is effective in elderly patients aged over 80 years. METHODS: Between July 2013 and June 2016, 207 patients with acute ischemic stroke in the anterior circulation received MT at our center. The applied MT strategies were forced arterial suction thrombectomy (FAST) and stent retriever thrombectomy. Patients were divided into those <80 years (n = 173) and those ≥80 years (n = 34). We compared clinical and angiographic parameters between groups. RESULTS: The median age was 67.5 in the younger group and 82 in the elderly group; 92.5% of the younger group and 70.6% of the elderly group received MT via the FAST technique. Angiographic outcomes, including procedural time, mTICI 2b-3 reperfusion (85.5% vs. 82.4%, p = 0.633), and symptomatic intracranial hemorrhage, were not different between the groups. A favorable clinical outcome rate was significantly higher in the younger group (62.4% vs. 44.1%, p = 0.047). Younger age, a low NIHSS score, and fast onset to reperfusion time were favorable prognostic factors in elderly patients. CONCLUSION: Modern MT in elderly patients with acute ischemic stroke is safe and effective compared to younger patients despite a lower favorable clinical outcome. Our findings may suggest that an appropriate MT strategy with respect to the location of the target occlusion and vascular tortuosity might be helpful to achieve fast reperfusion and improved outcomes for elderly patients.

Stereotactic radiosurgery for intracranial dural arteriovenous fistulas: its clinical and angiographic perspectives.

BACKGROUND: To assess the efficacy of stereotactic radiosurgery (SRS) for intracranial dural arteriovenous fistulas (DAVFs), the authors retrospectively reviewed our 7-year experience. We evaluated the obliteration rate, improvement in clinical symptoms, and complications. METHODS: Thirty patients with DAVF underwent SRS using a Gamma Knife between 2009 and 2015. Twenty-three patients were treated with SRS alone, and seven patients underwent SRS for residual or recurrent DAVFs after embolization or surgery. Chemosis, diplopia, and pulsating tinnitus were the most common symptoms. Median target volume was 2.9 cm3 (range, 0.8-13.6 cm3), and median radiation dose to the target was 17 Gy (range, 12-20 Gy). Median follow-up period was 33 months (range, 6-82 months). RESULTS: At the last neuroimaging follow-up, DAVFs were totally obliterated in 23 patients (77%) and subtotally in 7 (23%). At the last clinical follow-up, 21 patients (70%) showed complete recovery, and 9 (30%) showed incomplete recovery in symptoms or signs. None experienced worsening symptoms or signs. Asymptomatic perilesional edema after SRS occurred in one patient (3%). Total obliteration rates after SRS were 43% at 1 year, 79% at 2 years, and 95% at 5 years. Improvement rates of neurological function after SRS were 12% at 1 month, 52% at 2 months, 72% at 3 months, and 96% at 6 months. A multivariate analysis revealed that Borden type 1 (p = 0.019, hazard ratio, 3.254, 95% confidence interval, 1.216-8.707) was significantly associated with symptom improvement. CONCLUSIONS: SRS for intracranial DAVFs provided a high obliteration rate and a relatively low risk of radiation-induced complications. In selected benign cases without cortical venous drainage, SRS is a safe and effective treatment for symptom relief and fistula obliteration, even though the time course of improvement is longer than those of embolization and surgery.

Impact of Target Arterial Residual Stenosis on Outcome After Endovascular Revascularization.

BACKGROUND AND PURPOSE: Acute intracranial occlusion can be associated with in situ thrombo-occlusion in relation to preexisting intracranial atherosclerotic disease. We aimed to assess residual stenosis at the site of a target arterial lesion (TAL) to determine whether residual stenosis at the TAL is associated with underlying intracranial atherosclerotic disease. METHODS: One hundred and sixty-three patients who underwent endovascular therapy for M1 middle cerebral artery occlusion and achieved angiographic reperfusion were selected for analysis. The presence of residual stenosis at the TAL was classified using the Arterial Occlusive Lesion (AOL) scale at postprocedural angiography, and the severity of stenosis was grouped into none, mild (<50%), moderate (50%-69%), severe (70%-99%), and occlusion on postprocedural and follow-up angiography. We also recorded the incidence of instant reocclusion occurring during the procedure and delayed reocclusion detected on follow-up angiography. RESULTS: Seventy-four patients (45.5%) showed target arterial residual stenosis (AOL 2). As to the TAL pathogenesis, 40 patients were classified into in situ thrombo-occlusion (54.1% of AOL 2 and 24.5% of M1 occlusion). The occurrence of instant or delayed reocclusion was independently associated with a low chance of favorable 3-month outcome. Furthermore, the occurrence of delayed reocclusion was associated with excellent pretreatment collateral flow and early neurological worsening, but not the severity of residual stenosis at the TAL. CONCLUSIONS: In population with a high prevalence of intracranial atherosclerotic disease, residual stenosis may be attributed to in situ thrombo-occlusion with underlying intracranial atherosclerotic disease in ≈25% of cases, hindering functional recovery via the occurrence of instant or delayed reocclusion.

The efficacy of gamma knife radiosurgery alone as a primary treatment for intracranial dural arteriovenous fistulas.

BACKGROUND: The application of gamma knife radiosurgery (GKRS) alone has been expanded for dural arteriovenous fistulas (DAVFs). However, a standardized protocol delineating the appropriate circumstances for GKRS alone in cases of DAVF has yet to be determined. The purpose of this study was to report a single center's treatment algorithm for GKRS alone as a primary treatment for intracranial DAVFs and assess related clinical and radiological data. METHOD: Among 31 DAVF patients treated according to our institute's treatment algorithm between February 2009 and November 2014, 20 patients underwent GKRS alone. DAVF patients treated with GKRS alone fell in two main subgroups: DAVF patients without cortical venous reflux (CVR) but with symptoms (n = 8) and DAVF patients with CVR but without a high bleeding risk (defined as CVR with aggressive symptoms including hemorrhage or non-hemorrhagic neurological deficit, n = 11). One DAVF patient with a high bleeding risk had GKRS alone because of difficult endovascular access. Mean radiation volume was 4.8 cc (range, 0.7-14.2 cc), and mean maximal dose was 33.5 Gy (range, 28-38 Gy). RESULTS: At mean follow-up of 29.1 months (range, 8-69 months), radiological findings demonstrated complete cures in 18 patients (90 %) and subtotal cures in 2 patients (10 %). One patient had a transient complication, but no neurologic sign. All symptomatic patients showed complete resolution. CONCLUSIONS: Our treatment algorithm showed GKRS alone may serve as a primary treatment for patients with DAVFs regardless of location and presence of CVR, unless there is a high bleeding risk. However, a multicenter, prospective study is necessary to generalize our treatment algorithm.

Microembolic signal monitoring and the prediction of thromboembolic events following coil embolization of unruptured intracranial aneurysms: diffusion-weighted imaging correlation.

INTRODUCTION: Microembolic signal (MES) monitoring with transcranial Doppler ultrasonography (TCD) may allow for early prediction of thromboembolisms following endovascular coiling of unruptured intracranial aneurysms (UIAs). However, the method has not gained widespread use and may benefit from correlation with diffusion-weighted imaging (DWI) of acute ischemic lesions after coiling. This purposed to evaluate the relationship between MESs and DWI-positive lesions more precisely. METHODS: We conducted a prospective study on 45 consecutive patients. TCD was performed over the artery that is dependent on the site of aneurysm, but seven patients (15.6%) could not be examined due to the lack of an adequate cranial window. Consequently, 38 patients were available to detect MESs immediately (MES-1) and 24 h (MES-2) after coiling for UIAs. We also checked DWI 1 day after the coiling and analyzed correlations between the TCD and DWI findings. RESULTS: MES-1 and MES-2 were positive in 25 (65.7%) and 14 (36.8%) patients, respectively. DWI-positive lesions were seen in 20 (52.6%) patients, and only 1 (2.6%) patient was symptomatic. MES-1 and MES-2 were strongly correlated with the number of DWI-positive lesions (Spearman's correlation coefficient = 0.79 and 0.70, P < 0.01 and P < 0.01, respectively). Additionally, there was a significant correlation between MES-1 and MES-2 (Spearman's correlation coefficient = 0.70). CONCLUSION: Based upon the significant correlation between MES and DWI findings, MES may have a role for early detection of ischemic complications after coiling of UIAs. In addition, future study for further validation with clinical application seems requiring.

Instant reocclusion following mechanical thrombectomy of in situ thromboocclusion and the role of low-dose intra-arterial tirofiban.

BACKGROUND: An in situ thromboocclusion (IST) is defined as an infarct extensively involving all or most of a stenosed arterial territory, which is one major stroke mechanism related to intracranial atherosclerosis (ICAS). We focused on ISTs occurring in major cerebral arteries and analyzed their rate of instant reocclusion during mechanical thrombectomy (MT) compared with non-ISTs. Also, we introduced a treatment strategy of low-dose intra-arterial tirofiban administration to prevent such reocclusion following repeat recanalization, and evaluated its safety and efficacy. METHODS: We analyzed 168 consecutive patients treated with MT over a 2-year period from May 2011 to April 2013. During MT, if angiography following a successful recanalization showed stenosis at the occlusion site, we performed additional angiographic runs every 10 min for 30 min after the recanalization. Then, if angiography revealed reocclusion, we performed a repeat recanalization, using the same MT technique but additionally followed by low-dose intra-arterial tirofiban infusion. Time-of-flight MR angiography or CT angiography was performed to confirm any underlying ICAS at the occlusion site 5-7 days after the procedure. The patients who had confirmed underlying ICAS were included in the IST cohort. RESULTS: Of 168 enrolled patients, we excluded 36 who could not be checked for underlying ICAS at the occlusion site for one of the following reasons: recanalization failure (n = 11), rescue stenting after tirofiban failure (n = 5) and lack of follow-up vascular imaging (n = 20). The incidence of IST was 30.3% (40/132). All IST patients were confirmed to have underlying ICAS by follow-up vascular imaging. Instant reocclusion after successful recanalization was significantly more frequent in the IST cohort [26/40 (65%) vs. 3/92 (3.3%); p < 0.001]. Regarding the efficacy of low-dose intra-arterial tirofiban infusion, 85.7% of the reocclusion patients finally achieved a thrombolysis in cerebral infarction score 2/3 recanalization, but in the remaining 14.3% of the cases, the condition was refractory to the procedure and required rescue stenting. There were no cases of symptomatic intracranial hemorrhage following the procedure. CONCLUSIONS: In situ thromboocclusion was characterized by a significantly higher chance of instant reocclusion during MT. In such cases, low-dose intra-arterial tirofiban administration may be effective and safe. However, future confirmation by prospective multicenter trials seems necessary.

Critical age affecting 1-year functional outcome in elderly patients aged ≥ 70 years with aneurysmal subarachnoid hemorrhage.

BACKGROUND: While advanced age is already recognized as an independent risk factor for a poor functional outcome following an aneurysmal subarachnoid hemorrhage (SAH), it is also important to investigate the critical age for defining a higher risk population among elderly patients and the clinical grade at admission in order to provide a prognostic description and help guide the management of patients aged ≥ 70 years. METHODS: This retrospective study included 165 patients aged 70-90 years who underwent surgical or endovascular treatment for a ruptured aneurysm. In addition to medical and radiological data, telephone interviews were used to obtain the 1-year functional outcome. RESULTS: A multivariate analysis revealed age (p = 0.001) and the World Federation of Neurological Surgeons (WFNS) grade (p = 0.001), regardless of the treatment modalities (surgical versus endovascular), as significant risk factors for a poor outcome, while a receiver operating characteristic analysis revealed 75 years as an appropriate cutoff value for the patient age to predict a poor 1-year functional outcome (area under the curve: 0.683). For the patients aged 70-75 years with good (1-3) and poor (4-5) WFNS grades, 81.9 % and 42.9 % achieved a favorable outcome (modified Rankin Scale 0-3), respectively, whereas for the patients over the critical age (> 75 years) with good and poor WFNS grades, 54.8 % and 5.9 % achieved a favorable outcome, respectively. CONCLUSIONS: The long-term outcome for elderly patients with an aneurysmal SAH is affected primarily by the clinical condition at admission and the patient's age in relation to the critical age (> 75 years), regardless of the treatment modalities, including surgical clipping and endovascular coiling.

Minimally invasive and rapid surgical embolectomy (MIRSE) as rescue treatment following failed endovascular recanalization for acute ischemic stroke.

BACKGROUND: An intra-arterial (IA) mechanical thrombectomy has increased the recanalization rates for acute occlusion of proximal intracranial arteries. However, the current failure rate of endovascular recanalization remains at approximately 10%, resulting in the need for surgical rescue treatment. The authors applied a minimally invasive and rapid surgical embolectomy (MIRSE) as a final rescue treatment after the failure of endovascular recanalization, and investigated the incidence, technical feasibility, and treatment results. METHODS: For two years, from 2012 to 2013, a total of 131 patients with acute occlusion of proximal intracranial arteries underwent an IA mechanical thrombectomy using a Penumbra System and a Solitaire stent, yet ten (7.6%) patients still experienced final recanalization failure. Four (40%) of these ten patients subsequently underwent a MIRSE consisting of a superciliary keyhole approach, arteriotomy to remove the embolus, and arteriotomy repair techniques using aneurysm clips as the final repair material, or a temporary compartmentalizing clip. RESULTS: Four patients aged 39 to 78 years with an embolic occlusion in the middle cerebral artery (n = 1) and internal carotid artery (n = 3) were treated using a MIRSE. Complete recanalization was achieved in all four patients, and the time from skin incision to reperfusion was 40-50 minutes. The modified Rankin Scale (mRS) scores at 3 months after surgery were 1 (n = 2), 2 (n = 1), and 3 (n = 1), respectively. CONCLUSIONS: A MIRSE can be an effective rescue treatment after the failure of endovascular recanalization therapies for acute occlusion of proximal intracranial arteries if the patient is within the therapeutic time window.