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Among the various intraoperative neurophysiologic monitoring (IONM) techniques, transcranial motor-evoked potential (Tc-MEP) has recently become the most widely used method to monitor motor function. However, we often find that Tc-MEP is not sufficiently detected at the start of surgery. Therefore, we aimed to analyze the reasons and risk factors for not detecting sufficient baseline signal of Tc-MEP from the beginning of spinal surgery.We categorized IONM data from 1058 patients who underwent spine surgeries at a single institution from 2014 to 2020 and categorized them into 2 groups: 1) "poor MEP" if Tc-MEP could not be sufficiently obtained and 2) "normal MEP" if Tc-MEP could be sufficiently obtained from the surgery. We analyzed the patient's age, gender, underlying disease, operation type, level numbers, baseline motor function, existence of pathologic reflex, myelopathy, and duration from the onset and clinical diagnosis.The rate of failure to obtain sufficient baseline Tc-MEP signals in spine surgery was 21.8% (231/1058). Multivariate analysis showed significant associations of existence of diabetes mellitus, myelopathy, thoracic spine surgery, baseline motor deficit and tumor, and trauma disease with loss of meaningful and interpretable signals in baseline Tc-MEP (P0.05). Only 15 of 231 patients (6.4%) showed a trend of signal recovery after decompression procedures.Various factors (myelopathy, diabetes mellitus, thoracic surgery, baseline motor deficit, tumor, and trauma) were closely related to not obtaining sufficient baseline signals for Tc-MEP. When operating on patients with these considerations, we need to consider the efficacy and usefulness of Tc- MEP.

Neurovascular compression syndrome is generally caused by vascular compression at the root entry or exit zone of the corresponding cranial nerve. Trigeminal neuralgia is the most frequent syndrome, followed by hemifacial spasm. Despite ongoing debate in the literature, pulsatile tinnitus is also known to be a neurovascular compression syndrome resulting from vascular compression of the vestibulocochlear nerve. Combined manifestations of neurovascular compression symptoms are very rare. We report a case with a simultaneous manifestation of trigeminal neuralgia, hemifacial spasm, and pulsatile tinnitus as neurovascular compression syndrome with separate offending vessels. A 53-year-old female presented with lancinating pain in the left face, left hemifacial spasm, and ipsilateral pulsatile tinnitus for 2 years. Trigeminal neuralgia and hemifacial spasm were diagnosed after a neurological examination, imaging study, and electromyography. Microvascular decompression via a retrosigmoid approach for separate offenders, including the superior cerebellar artery, anterior inferior cerebellar artery, and posterior inferior cerebellar artery was performed using Teflon sponges. The patient’s hemifacial spasm, pulsatile tinnitus, and hemifacial pain improved immediately after microvascular decompression.

Our study's purpose was to determine the most reliable Hounsfield unit (HU) measurement method to reflect bone mineral density (BMD) on cervical spine computed tomography (CT) and to identify any factors that influence these results.We retrospectively analyzed 439 consecutive patients with mild head and neck injuries. Mean HU values of the C2-C7 vertebra were determined on each sagittal, coronal, and axial CT image. Correlation patterns were analyzed between the HU value and corresponding dual-energy X-ray absorptiometry (DXA) in the lumbar vertebra (T-score) and femoral neck (T-score). A sub-group analysis was performed according to patient age, sex, and degree of spinal degeneration.The correlation coefficients for HU and DXA ranged from 0.52 to 0.65 in all cervical segments. A simple linear regression analysis revealed the following formula: T-score = 0.01 × (HU) - 4.55. The mean HU values for osteopenia and osteoporosis were 284.0 ± 63.3 and 231.5 ± 52.8, respectively. The ROC curve indicated that the HU method has a sensitivity of 89.2% and specificity of 88.7% to diagnose osteoporosis. The HU measurement showed a high correlation value (range: r = 0.64-0.70) with spine DXA score regardless of the degree of degeneration or patient age or sex.HU values using the upper two cervical vertebrae (C2 and C3) reflected a more reliable BMD level than other segments. Additionally, the HU of cervical CT provided reliable information regardless of measurement plane, age or sex, and degree of degeneration.

Objective : Accurate measurement of T1 slope (a component of T1s minus cervical lordosis [CL]) is often constrained by anatomical limitations. In this situation, efforts should be made to find the exact meaning of T1s-CL and whether there are any alternatives to it.Methods : We enrolled 117 patients who received two-level anterior cervical discectomy and fusion (ACDF). Occipital slope, C2 slope (C2s), C7 slope (C7s), T1, O-C2 angle (O-C2A), C2-7 angle (C2-7A), O-C7 angle (O-C7A), T1s-CL, C7-T1 angle (C7-T1A), and C2-7 sagittal vertical axis were measured. We determined 16° (T1s-CL) as the reference point for dividing subjects into the mismatch group and the balance group, and a comparative analysis was performed.Results : The mean value of C7-T1A was constantly maintained within 2.6° peri-operatively. In addition, C2s and T1s-CL showed the same absolute change (Δ|0.8|°). The mean values of T1s-CL of the mismatch and balance groups were 23.0° and 7.6°, respectively. The five factors with the largest differences between the two groups were as follows : C2s (Δ13.3°), T1s-CL (Δ15.4°), O-C2A (Δ8.7°), C2-7A (Δ14.7°), and segmental angle (Δ7.9°) before surgery. Only four factors showed statistically significant change between the two groups after ACDF : T1s-CL (Δ4.0° vs. Δ0.2°), C2s (Δ3.2° vs. Δ0.7°), O-C2A (Δ2.6° vs. Δ1.3°), C2-7A (Δ6.3° vs. Δ1.3°). A very strong correlation between T1s-CL and C2s was also found (r=|0.88–0.96|).Conclusion : C2s itself may be the essential key to represent T1s-CL. The amounts and directions of change of these two factors (T1s-CL and C2s) were also almost identical. The above phenomenon was re-confirmed once again through the correlation analysis.

BACKGROUND Modified orbitozygomatic craniotomy is characterized by simplicity and wide exposure. The purpose of the present study was to describe a modified orbitozygomatic approach without resecting the zygomatic arch for large parasellar tumor surgeries. METHODS Between April 2016 and December 2019, seven patients with parasellar tumor underwent surgiest with a modified orbitozygomatic approach. Surgical procedures, clinical outcomes, and complications were analyzed. RESULTS This study included 3 meningiomas, 2 pituitary adenomas, 1 chondrosarcoma, and 1 schwannoma. Modified orbitozygomatic craniotomy provides a wider surgical freedom in the opticocarotid and prechiasmatic cistern than frontotemporal craniotomy without orbitotomy, Total, subtotal, and partial resections were achieved for 3, 2, and 2 patients, respectively. Reasons for partial resections were tight adhesion to the carotid artery and encasing of the carotid artery. Permanent morbidities developed in one patient with 3rd nerve palsy and one patient with hemiparesis. CONCLUSION Modified orbitozygomatic approach can provide the shortest access to the interpeduncular cistern with a minimum brain retraction. Surgeons who experience surgical challenge during the conventional approach for parasellar tumor resection are recommended to learn the modified orbitozygomatic approach.

Inflammation plays a pivotal role in acute ischemic stroke, and various inflammatory markers are known to predict prognosis of acute ischemic stroke. This study aimed to evaluate the prognostic value of systemic inflammation response index (SIRI) and systemic immune-inflammation index (SII) after mechanical thrombectomy (MT) for acute ischemic stroke caused by large artery occlusion.The study enrolled 440 patients who underwent MT for large artery occlusion. SIRI and SII were calculated using laboratory data on admission. Prognosis was estimated with modified Rankin Scale at 3 months, and favorable clinical outcome was defined by a modified Rankin Scale score of 0-2. Receiver operating characteristic analysis was used to calculate the optimal cutoff values of SIRI and SII for predicting clinical outcome. Multivariate analysis was used to assess the relationship of SIRI and SII with clinical outcome.In receiver operating characteristic analysis, the optimal cutoff values for SIRI and SII were 2.9 and 853, respectively (area under the curve 0.799, 95% confidence interval [CI] 0.756-0.843, P0.001 and area under the curve 0.679, 95% CI 0.643-0.745, P0.001, respectively). Multivariate analysis revealed that SIRI2.9 (odds ratio 2.27, 95% CI 1.29-5.17, P = 0.019) and SII853 (OR 1.82, 95% CI 1.16-3.10, P = 0.031) were independent predictors of favorable clinical outcome after MT.Decreased SIRI and SII were associated with favorable clinical outcome after MT. SIRI and SII represent potential prognostic factors in patients undergoing MT for large artery occlusion.

Introduction: Susceptibility-Eeighted Imaging (SWI) enables visualization of thrombotic material in acute ischemic stroke. We analyzed the association between thrombus length on SWI and the success rate of recanalization in stent-retriever mechanical thrombectomy. Methods: A retrospective study was performed on 128 patients with Middle Cerebral Artery (MCA) thrombus on pretreatment SWI. The patients were divided into 2 groups, the successful recanalization and the failed recanalization group. Thrombus visibility and location on SWI were compared to those on Maximum Intensity Projection (MIP) in Computed Tomography (CT) angiography. A comparative analysis was performed in terms of clinical and radiologic outcomes as well as complications with respect to multiple categories. Results: No significant differences were noted in terms of baseline characteristics and clinical outcomes between the 2 groups. However, compared with the successful recanalization group, the failed recanalization group had a larger number of stent-retriever passages and a longer thrombus length (p = 0.027 and 0.014, respectively). Multivariate analyses revealed that a larger mean number of stent-retriever passages was a predictive factor for failure of recanalization (odds ratio [OR] 1.60; 95% confidence Interval [CI] 1.12-2.08; p = 0.04). Thrombus length (OR 9.91; 95% CI 3.89-13.87; p < 0.001) and atrial fibrillation (OR 5.38; 95% CI 1.51-9.58; p = 0.008) were separately associated with more than 3 stent-retriever passages. Conclusions: Thrombus length has been identified as a predictor of recanalization failure in mechanical thrombectomy. A significant decline in the success rate of recanalization was associated with longer thrombus length.

Objective: Mechanical thrombectomy (MT) is an effective treatment for large vessel occlusion (LVO) with a high successful recanalization (SR) rate. However, MT fails in a proportion of patients, leading to poor clinical outcomes. We analyzed the factors associated with the failure of MT. Methods: Failed MT was observed in 97 patients (14.3%). Among them, 69 patients (10.2% of the entire cohort, 71.1% of the failed MT group) were included in the RF group. Propensity matching analysis with 69 patients in each group showed that the RF group had a higher rate of residual intracranial atherosclerotic stenosis (ICAS) than the SR group (30.4% vs. 14.5% P = 0.003). The rates of 4 or more passages and no change of method were significantly higher in the RF group than in the SR group (34.8% vs. 13.0%; P = 0.001 and 28.9% vs. 8.7%; P = 0.001). Results: Failed MT was observed in 97 patients (14.3%). Among them, 69 patients (10.2% of the entire cohort, 71.1% of the failed MT group) were included in the RF group. Propensity matching analysis with 69 patients in each group showed that the RF group had a higher rate of residual intracranial atherosclerotic stenosis (ICAS) than the SR group (30.4% vs. 14.5% P = 0.003). The rates of 4 or more passages and no change of method were significantly higher in the RF group than in the SR group (34.8% vs. 13.0%; P = 0.001 and 28.9% vs. 8.7%; P = 0.001). Conclusion: The failure rate for all of the MT was approximately 15%, and RF accounted for more than 70% of the failed MT. RF was associated with residual ICAS. In cases with RF, even in repeated attempts for recanalization, an alteration of the thrombectomy method should be considered.

Although Neuroform Atlas stent is commonly used in stent-assisted coiling (SAC) to treat ruptured intracranial aneurysms (RIA), its safety and efficacy remain controversial.To assess the safety and efficacy of SAC using Neuroform Atlas for treating RIA compared with coiling alone by performing a propensity score matching analysis.RIA treated with coiling alone and SAC between January 2017 and May 2021 were retrospectively reviewed. Demographics, periprocedural complication rates, angiographic outcomes, and clinical outcomes of the SAC using Neuroform Atlas group and the coiling-alone group were analyzed with 1:1 propensity score matching.A total of 375 aneurysms were enrolled, and 274 (63.1%) aneurysms were treated with coiling alone. In total, 101 (26.9%) aneurysms were treated with SAC, and Neuroform Atlas stent was used in 71 aneurysms. In propensity score matching, the SAC using Neuroform Atlas group showed higher incidence of complete occlusion (69.0% vs 56.3%, P = .029), lower rate of recanalization (11.3% vs 25.4%, P = .011), and lesser need for retreatment (7.0% vs 16.9%, P = .016) compared with the coiling-alone group. However, there were no significant differences in periprocedural complications such as intraprocedural thrombosis or postprocedural cerebral infarct between the 2 groups.The use of Neuroform Atlas is safe and effective for SAC in RIA with comparable procedure-related complication rates but better angiographic outcome in comparison with coiling alone.

Objective: Mechanical thrombectomy (MT) is an effective treatment for patients suffering from acute ischemic stroke secondary to large vessel occlusion. However, recanalization failure rates of interventions were about 20% in literature studies. We report our experience of unsuccessful MT with a focus on technical reasons.Methods: From December 2010 to June 2021, six hundred eight patients with acute ischemic stroke due to large artery occlusion received MT using a stent retriever with or without an aspiration catheter in our institution. We divided the reasons for failure into six categories. We analyzed the reasons for failure by dividing our experience time into 3 periods.Results: A total of 608 cases of thrombectomy for large vessel occlusion were identified in the study period. The successful recanalization rate was 90.4%. In most of the cases (20/57, 35%), the thrombus persisted despite several passes, and the second most common cause was termination of the procedure even after partial recanalization (10/57, 18%). Similar proportions of in-stent occlusion, distal embolization, and termination due to vessel rupture were observed. On analysis of three periods, the successful recanalization rate improved over time.Conclusions: MT fails due to various reasons, and intracranial artery stenosis is the main cause of MT failure. With the development of rescue techniques, the failure rate has gradually decreased. Further development of new devices and techniques could improve the recanalization rates.

Objective Cerebral edema is the predominant mechanism of secondary inflammation after intracerebral hemorrhage (ICH). Pioglitazone, peroxisome proliferator-activated receptor gamma agonist has been shown to play a role in regulation of central nervous system inflammation. Here, we examined the pharmacological effects of pioglitazone in an ICH mouse model and investigated its regulation on NLRP3 inflammasome and glucose metabolism. Methods The ICH model was established in C57 BL/6 mice by the stereotactical inoculation of blood (30 µL) into the right frontal lobe. The treatment group was administered i.p. pioglitazone (20 mg/kg) for 1, 3, and 6 days. The control group was administered i.p. phosphate-buffered saline for 1, 3, and 6 days. We investigated brain water contents, NLRP3 expression, and changes in the metabolites in the ICH model using liquid chromatography-tandem mass spectrometry. Results On day 3, brain edema in the mice treated with pioglitazone was decreased more than that in the control group. Expression levels of NLRP3 in the ICH model treated with pioglitazone were decreased more than those of the control mice on days 3 and 7. The pioglitazone group showed higher levels of glycolytic metabolites than those in the ICH mice. Lactate production was increased in the ICH mice treated with pioglitazone. Conclusion Our results demonstrated less brain swelling following ICH in mice treated with pioglitazone. Pioglitazone decreased NLRP3-related brain edema and increased anaerobic glycolysis, resulting in the production of lactate in the ICH mice model. NLRP3 might be a therapeutic target for ICH recovery.

Objective The Solitaire Platinum 4×40 mm stent retriever contains radiopaque markers with a long length. We evaluated the effect of Solitaire Platinum 4×40 mm stent retriever in Solumbra technique thrombectomy, and compared it with shorter Solitaire stent retrievers. Methods A total of 70 patients who underwent Solumbra technique thrombectomy with equal diameter (4 mm) and different length (40 vs. 20 mm) Solitaire stent retrievers were divided into two groups : the Solitaire Platinum 4×40 mm stent (4×40) group and the Solitaire FR 4×20 mm stent or Solitaire Platinum 4×20 mm stent (4×20) group. The clinical outcomes, Thrombolysis in Cerebral Infarction score, the first pass reperfusion status, and complications were evaluated and compared between the two groups. Multivariate analysis was performed to evaluate the predictive factors for reperfusion and complete reperfusion from the first pass. Results Higher first-pass reperfusion and complete reperfusion were achieved in the 4×40 group (68.0% and 48.0%) than in the 4×20 group (46.7% and 33.3%; p=0.004 and 0.007, respectively). In multivariate analysis, radiopaque device and longer stent retriever were correlated with first-pass reperfusion (p=0.014 and 0.008, respectively) and first-pass complete reperfusion (p=0.022 and 0.012, respectively). Conclusion Our study demonstrated the usefulness of the Solitaire Platinum 4×40 mm stent retriever, which led to higher firstpass reperfusion and complete reperfusion rates than the Solitaire FR 4×20 mm stent or the Solitaire Platinum 4×20 mm stent, especially in Solumbra technique thrombectomy.

Objective: We investigated whether intravenous thrombolysis (IVT) affected the outcomes and complications of mechanical thrombectomy (MT), specifically focusing on thrombus fragmentation. Methods: The patients who underwent MT for large artery occlusion (LAO) were classified into two groups: MT with prior IVT (MT+IVT) group and MT without prior IVT (MT-IVT) group. The clinical outcome, successful recanalization with other radiological outcomes, and complications were compared, between two groups. Subgroup analysis was also performed for patients with simultaneous application of stent retriever and aspiration. Results: There were no significant differences in clinical outcome and successful recanalization rate, between both groups. However, the ratio of pre- to peri-procedural thrombus fragmentation was significantly higher in the MT+IVT group (14.6% and 16.2%, respectively; P=0.004) compared to the MT-IVT group (5.1% and 6.8%, respectively; P=0.008). The MT+IVT group required more second stent retriever (16.2%), more stent passages (median value = 2), and more occurrence of distal emboli (3.9%) than the MT-IVT group (7.9%, median value = 1, and 8.1%, respectively) (P=0.004, 0.008 and 0.018, respectively). In subgroup analysis, the results were similar to those of the entire patients. Conclusion: Thrombus fragmentation of IVT with t-PA before MT resulted in an increased need for additional rescue therapies, and it could induce more distal emboli. The use of IVT prior to MT does not affect the clinical outcome and successful recanalization, compared with MT without prior IVT. Therefore, we need to reconsider the need for IVT before MT.

The absolute value of the cervical sagittal parameters cannot be guaranteed with certainty on all follow-up cervical radiographs. With the assumption that neck posture changes can occur at any time at each follow-up radiographic session, we examined whether the sagittal parameters change meaningfully and identified the factors most closely related to the C2-C7 sagittal vertical axis (SVA).We enrolled 200 patients who had undergone either anterior cervical fusion (n = 100) or posterior cervical fusion (n = 100). The craniovertebral angle (CVA), mandible angle (MA), occipital slope (Os), C2 slope (C2s), C7 slope (C7s), and C2-C7 SVA were measured on 2 different follow-up radiographs after surgery. The C2-C7 angle (C2-C7A) and changes (Δ) in the sagittal parameters between the 2 radiographs were then calculated.The ΔC2s and ΔCVA showed a very strong correlation with the ΔC2-C7 SVA (r = |0.70-0.93|). An independent t test showed a statistically significant difference for multiple sagittal parameters (i.e., ΔMA, ΔOs, ΔC2s, ΔC7s, and ΔCVA) between the large and small ΔC2-C7 SVA groups. In contrast, the change in the C2-C7A was without statistical significance. A stepwise multivariate regression analysis revealed a high adjusted R2 value (0.841) between the ΔC2-C7 SVA and 2 parameters (standardized coefficient: ΔCVA, -0.563; ΔC2s, -0.398).During cervical fusion surgery, the CVA was the most predictable parameter reflecting the C2-C7 SVA in various analyses. The upper cervical parameters (Os and C2s) provided more explanatory power regarding the C2-C7 SVA changes than did the lower cervical parameter (C7s) or the presence of cervical lordosis (C2-C7A).

BackgroundAntiplatelet therapy, where regimens are tailored based on platelet function testing, has been introduced into neurointerventional surgery. This nationwide registry study evaluated the effect and safety of tailored antiplatelet therapy in stent assisted coiling for unruptured aneurysms compared with conventional therapy using a standard regimen.MethodsThis study enrolled 1686 patients in 44 participating centers who received stent assisted coiling for unruptured aneurysms between January 1, 2019 and December 31, 2019. The standard regimen (aspirin and clopidogrel) was used for all patients in the conventional group (924, 19 centers). The regimen was selected based on platelet function testing (standard regimen for clopidogrel responders; adding cilostazol or replacing clopidogrel with other thienopyridines (ticlopidine, prasugrel, or ticagrelor) for clopidogrel non-responders) in the tailored group (762, 25 centers). The primary outcome was thromboembolic events. Secondary outcomes were bleeding and poor outcomes (increase in modified Rankin Scale score). Outcomes within 30 days after coiling were compared using logistic regression analysis.ResultsThe thromboembolic event rate was lower in the tailored group than in the conventional group (30/762 (3.9%) vs 63/924 (6.8%), adjusted OR 0.560, 95% CI 0.359 to 0.875, P=0.001). The bleeding event rate was not different between the study groups (62/762 (8.1%) vs 73/924 (7.9%), adjusted OR 0.790, 95% CI 0.469 to 1.331, P=0.376). Poor outcomes were less frequent in the tailored group (12/762 (1.6%) vs 34 (3.7%), adjusted OR 0.252, 95% CI 0.112 to 0.568, P=0.001).ConclusionTailored antiplatelet therapy in stent assisted coiling for unruptured aneurysms reduced thromboembolic events and poor outcomes without increasing bleeding.

Background This study aims to evaluate the safety and effects of using argatroban, immediately after mechanical thrombectomy (MT) with large artery occlusion. Methods A total of 302 patients were divided into 2 groups: the MT with post argatroban (MT+ARG) group and the MT without post argatroban (MT–ARG) group. Baseline characteristics, time interval categories, and results of MT were reviewed. Outcome assessment with the National Institutes of Health Stroke Scale, modified Rankin Scale, TICI, reocclusion, and various complications were evaluated and compared between the 2 groups. Subgroup analysis was also performed for patients using tissue plasminogen activator or tirofiban. Results Baseline characteristics and time intervals were similar for the 2 groups. The MT+ARG group showed significantly less occurrence of reocclusion at 24 hours and 7 days compared with the MT–ARG group (2.5% vs. 6.0%, P = 0.018; 4.2% vs. 8.2%, P = 0.020). However, there were no significant differences in incidence of complications such as brain hemorrhage between the 2 groups. In subgroup analysis with tissue plasminogen activator, the MT+ARG group showed less occurrence of reocclusion at 24 hours and 7 days compared with the MT–ARG group (P = 0.008 and P = 0.018, respectively). In subgroup analysis with tirofiban, reocclusion at 7 days occurred less in the MT+ARG group (P = 0.040). Conclusions This study showed the safety and usefulness of argatroban immediately after MT, indicating that using argatroban after MT could prevent reocclusion of target artery without increasing bleeding complications.

Objective Since less invasive endovascular treatment was introduced to South Korea in 1994, a considerable proportion of endovascular treatments have been performed by neuroradiology doctors, and endovascular treatments by vascular neurosurgeons have recently increased. However, few specific statistics are known regarding how many endovascular treatments are performed by neurosurgeons. Thus, authors compared endovascular treatments collaboratively performed by vascular neurosurgeons with all cases throughout South Korea from 2013 to 2017 to elucidate the role of neurosurgeons in the field of endovascular treatment in South Korea. Methods The Society of Korean Endovascular Neurosurgeons (SKEN) has issued annual reports every year since 2014. These reports cover statistics on endovascular treatments collaboratively or individually performed by SKEN members from 2013 to 2017. The data was requested and collected from vascular neurosurgeons in various hospitals. The study involved 77 hospitals in its first year, and 100 in its last. National statistics on endovascular treatment from all over South Korea were obtained from the Healthcare Bigdata Hub website of the Health Insurance Review & Assessment Service based on the Electronic Data Interchange (EDI) codes (in the case of intra-arterial (IA) thrombolysis, however, statistics were based on a combination of the EDI and I63 codes, a cerebral infarction disease code) from 2013 to 2017. These two data sets were directly compared and the ratios were obtained. Results Regionally, during the entire study period, endovascular treatments by SKEN members were most common in Gyeonggido, followed by Seoul and Busan. Among the endovascular treatments, conventional cerebral angiography was the most common, followed by cerebral aneurysmal coiling, endovascular treatments for ischemic stroke, and finally endovascular treatments for vascular malformation and tumor embolization. The number of endovascular treatments performed by SKEN members increased every year. Conclusion The SKEN members have been responsible for the major role of endovascular treatments in South Korea for the recent 5 years. This was achieved through the perseverance of senior members who started out in the midst of hardship, the establishment of standards for the training/certification of endovascular neurosurgery, and the enthusiasm of current SKEN members who followed. To provide better treatment to patients, we will have to make further progress in SKEN.

Background We report the experience of the FlowGate2 (FG2) as a new balloon guide catheter in endovascular stroke intervention. Methods We evaluated the various outcomes and complications of patients with intracranial large artery occlusion undergoing endovascular stroke intervention with FG2 at our center. Baseline characteristics (failure rate of device application, sex, age, risk factors, arterial occlusion sites, and time intervals) were reviewed. Outcomes were evaluated according to National Institutes of Health Stroke Scale score, modified Rankin Scale (mRS) score, number of stent passages required, and Thrombolysis in Cerebral Infarction score. The incidence of hemorrhage, vessel damage, distal emboli, and mortality rate were evaluated as indicators of complications. Results Overall, 70 patients were enrolled, except the 2 patients with application failure of FG2. Seventy patients with a median age of 69 years were treated with FG2. Arterial occlusion involved the M1 (50%) and M2 (14.3%) segments, internal carotid artery (25.7%), and posterior circulation (10%). Median value of mRS at 90 days was 2.8, and 37 patients (52.8%) had a mRS score ≤2. The recanalization rate in patients with a Thrombolysis in Cerebral Infarction score of 2b or 3 was 91.4%. The hemorrhage rate was 5.7%, but none were symptomatic. In terms of complications, distal emboli occurred in 4.3% of cases. Conclusions Endovascular stroke intervention with the FG2 is safe and effective with good accessibility and less occurrence of distal emboli. Its trackability, stability, and luminal size make the FG2 suitable for stroke intervention.

Objective The purpose of this study was to investigate neck movement and various conditions of the aortic arch that may hinder access to the carotid artery during neurointerventional procedures. Methods We reviewed 230 patients who underwent internal carotid artery angiography between February 2016 and October 2016. Use of a Davis catheter (DC) was first attempted and if not possible, movement (right, left, flexion, and extension) of the patient's head was tried before catheter exchange. We analyzed the success rate after neck motion in relation to various aortic arch factors. Results Only extension of the patient's neck was effective. Of the 209 patients with right side angiography, 23 had failed access with a DC, but neck extension was effective in 3 patients (13%). Failure to insert a DC was significantly correlated with age, male sex, acute angle, arch elongation, aortic calcification, and carotid artery angulation on the right side, whereas access was not gained in 24 out of 208 patients who underwent left side angiography, and neck extension was successful in 7 patients (29.2%). Also, significant factors determining the catheter exchange were age, male sex, acute angle, arch elongation, and aortic calcification.In the DC access failure group, neck extension was significantly more effective for younger aged patients (P = 0.011). Conclusions Factors such as older age, acute arch angle, higher elongation type, arch calcification, and carotid artery angulation were verified as factors affecting access by a simple catheter; however, neck extension was shown to facilitate access in about 10%-30% of patents.

Objective In presurgical planning for intracranial meningiomas, the relationship between tumors and adjacent vasculature must be identified. The purpose of this study was to evaluate the usefulness of 3-dimensional digital subtraction angiography (3D-DSA) with dual-volume visualization (DVV). Methods Between February 2013 and April 2016, 26 patients with intracranial meningiomas enrolled in this study. Two or 3 days before surgery, 3D-DSA with DVV was performed for presurgical planning. If necessary, the tumor was simultaneously embolized. Results Vascular supply and disfiguration observed by preoperative 3D-DSA with DVV closely resembled those actually observed during surgery. All but 2 patients had total tumor resection (Simpson grade 1 or 2). Three of 26 patients had new neurologic deficits. Conclusions 3D-DSA with DVV may be useful for preoperative planning by allowing the surgeon to identify the relationship between a tumor and peritumoral vasculature before meningioma surgery. Young neurosurgeons with little experience may benefit most from this technique.

Objective Globus pallidus interna (GPi) is acknowledged as an essential treatment for advanced Parkinson's disease (PD). Nonetheless, the neurotransmitter study about its results is undiscovered. The goal of this research was to examine influences of entopeduncular nucleus (EPN) stimulation, identical to human GPi, in no-lesioned (NL) rat and 6-hydroxydopamine (6-HD)-lesioned rat on glutamate change in the striatum. Methods Extracellular glutamate level changes in striatum of NL category, NL with deep brain stimulation (DBS) category, 6-HD category, and 6-HD with DBS category were examined using microdialysis and high-pressure liquid chromatography. Tyrosine hydroxylase (TH) immunoreactivities in substantia nigra and striatum of the four categories were also analyzed. Results Extracellular glutamate levels in the striatum of NL with DBS category and 6-HD with DBS category were significantly increased by EPN stimulation compared to those in the NL category and 6-HD category. EPN stimulation had no significant effect on the expression of TH in NL or 6-HD category. Conclusion Clinical results of GPi DBS are not only limited to direct inhibitory outflow to thalamus. They also include extensive alteration within basal ganglia.

Objectives Inflammatory response plays a pivotal role in the progress of aneurysmal subarachnoid hemorrhage (aSAH). As novel inflammatory markers, systemic inflammation response index (SIRI) and systemic immune-inflammation (SII) index could reflect clinical outcomes of patients with various diseases. The aim of this study was to ascertain whether initial SIRI and SII index were associated with prognosis of aSAH patients. Methods A total of 680 patients with aSAH were enrolled. Their prognosis was evaluated with modified Rankin Scale (mRS) at 3 months, and unfavorable clinical outcome was defined as mRS score of 3-6. Receiver operating characteristic (ROC) curve analysis was performed to identify cutoff values of SIRI and SII index for predicting clinical outcomes. Univariate and multivariate regression analyses were performed to explore relationships of SIRI and SII index with prognosis of patients. Results Optimal cutoff values of SIRI and SII index to discriminate between favorable and unfavorable clinical outcomes were 3.2 × 109/L and 960 × 109/L, respectively (P Conclusions SIRI and SII index values are associated with clinical outcomes of patients with aSAH. Elevated SIRI and SII index could be independent predicting factors for a poor prognosis after aSAH.

The aim of study was aimed to investigate associations of platelet-to-neutrophil ratio (PNR) and platelet-to-lymphocyte ratio (PLR) on admission with clinical outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH). A retrospective analysis was performed on patients who were treated for aSAH. Unfavorable clinical outcome was defined as Modified Rankin Scale (mRS) score of 3-6 at 90-days. Receiver operating characteristic curve analysis was performed to detect optimal cutoff values of PNR and PLR for predicting clinical outcomes. Logistic regression was used to explore associations of PNR and PLR with clinical outcomes. A total of 544 patients with aSAH were enrolled. Of them, 152 (29.9%) had unfavorable clinical outcome. Optimal cutoff values of PNR and PLR to predict clinical outcomes at 90 days after aSAH were 25 and 130, respectively (P 0.001 and 0.001, respectively). In multivariate logistic regression analysis, PNR 25 and PLR ≥ 130 were associated with unfavorable clinical outcome at 90 days after aSAH (odds ratio [OR]: 1.81; 95% confidence interval [CI]: 1.23-3.69; P = 0.018 and OR: 1.56; 95% CI: 1.18-2.62; P = 0.031, respectively). PNR and PLR as novel inflammatory biomarkers could predict the clinical outcome after aSAH. PNR 22 and PLR ≥ 130 were associated with unfavorable clinical outcome at 90 days after aSAH.

Purpose To evaluate image features and diagnostic performance of susceptibility-weighted image (SWI) in detection of intracranial vertebral artery dissection (VAD) and unruptured intracranial aneurysm (UIA). Materials and methods From January 2015 to December 2021, symptomatic patients who underwent 3.0 T MR SWI were recruited. For study group, transfemoral cerebral angiography-proven lesions were included, while 1:1 matched control group with MR angiography were included. Image features of SWI were evaluated. Diagnostic performance and interobserver agreements were calculated for detecting VAD with stenosis and UIA greater than 7 mm. Results Total of 110 patients (mean age: 60.92 years, female: 60/110) were included. In the study group (N = 55), 21 patients (38.2%) had VAD, while 34 patients (61.8%) had UIA. For SWI-detectable VAD, larger parent artery (PA)-dilatation ratio was observed (1.36 vs. 1.84, p = 0.034). For SWI-detectable UIA, larger PA-dome ratio (1.32 vs. 1.90, p = 0.020) and larger PA-height ratio (1.25 vs. 1.77, p = 0.005) were observed. The diagnostic performance and kappa values for VAD with stenosis were as follow: sensitivity: 91.7 (95% CI: 61.5–99.8); specificity: 93.9 (95% CI: 87.2–97.7); к: 0.80. The diagnostic performance for UIA larger than 7 mm were as follow: sensitivity: 87.5 (95% CI: 47.4–99.7); specificity: 95.1 (95% CI: 88.9–98.4); к: 0.73. Conclusion SWI-detectable lesions were VAD with larger PA-dilatation ratio, and UIA with larger PA-dome ratio, and PA-height ratio. SWI was able to accurately detect VAD with stenosis and UIA larger than 7 mm with substantial interobserver agreements.

Objective: Our study investigated the association between the level of HbA1c (glycated hemoglobin) at admission and the prognosis of aneurysmal subarachnoid hemorrhage (SAH). Methods: A total of 510 patients treated with neuro-intervention for aneurysmal SAH and with data for admission HbA1c (glycated hemoglobin) were included. Favorable clinical outcome was defined as modified Rankin Scale (mRS) score of 0-2 at 3 months. Receiver operating characteristic (ROC) curve analysis was used to identify the optimal cutoff value of HbA1C for unfavorable clinical outcomes. Logistic regression was used to evaluate the association between HbA1C level and outcomes. Results: The optimal cutoff value of HbA1C was identified as 6.0% (P < 0.001), and patients with a high HbA1C (≥ 6.0%) had a lower prevalence of favorable clinical outcomes than patients with low HbA1C (< 6.0%) (P < 0.001). High HbA1C (≥ 6.0%) was independently associated with unfavorable clinical outcome (OR 2.84; 95% CI: 1.52-5.44; P = 0.004). The risk of unfavorable clinical outcome was significantly increased in patients with HbA1C (≥ 7.0%, < 8%) and HbA1C (≥ 8.0%) compared with lower baseline HbA1C (≥ 6.0%, < 7%) values (OR 2.17; 95% CI: 1.87-5.13; P = 0.011 and OR 4.25; 95% CI: 3.17-8.41; P = 0.005). Conclusions: Our study showed that HbA1C could be an independent predictor of worse outcomes following neuro-intervention for aneurysmal SAH. High HbA1C (≥ 6.0%) was associated with unfavorable clinical outcomes, and gradual elevation of HbA1C contributed to an increase in the risk of worse clinical outcomes after SAH.

BACKGROUND: Elevated blood viscosity has been reported as a risk factor for cerebrovascular disease. OBJECTIVE: The relationship between blood viscosity and outcomes of mechanical thrombectomy (MT) for large artery occlusion (LAO) were investigated in the present study. METHODS: A total of 238 patients were enrolled and systolic blood viscosity (SBV) and diastolic blood viscosity (DBV) were measured using the scanning capillary tube viscometer. Receiver operating characteristic (ROC) analysis was performed to specify the association of viscosity with the first-pass reperfusion (FPR). Multivariable and regression analyses were performed to evaluate the relationship of viscosity with FPR and various variables. RESULTS: Based on ROC analysis, the best DBV cutoff value was 10.55 (cP). In multivariable analysis, high DBV was associated with FPR failure (odds ratio 2.82, 95% confidence interval 1.64–4.22; p = 0.001). Increased DVB could be associated with elevated SBV, hematocrit level, and blood urea nitrogen/creatinine ratio (p =

Objective: Prognostic significance of inflammatory response has been reported in various diseases. The objective of this study was to analyze the association between inflammation- based scores and the prognosis of patients who underwent neuro-intervention for aneurysmal subarachnoid hemorrhage (SAH). Methods: Inflammation-based scores such as neutrophil to lymphocyte ratio (NLR), lymphocyte to monocyte ratio (LMR), and monocyte to high-density lipoprotein cholesterol (HDL-C) ratio (MHR) were analyzed for aneurysmal SAH patients who underwent endovascular intervention. Unfavorable functional outcome was defined as a modified Rankin Scale (mRS) score of 3-6. Receiver operating characteristic (ROC) curve analysis was performed to identify cut-off values of inflammation- based scores for predicting unfavorable functional outcome. Logistic regression analyses were performed to explore the relationship between inflammation-based scores and the prognosis of patients. Results: A total of 498 patients were enrolled. Optimal cutoff values of inflammation-based scores of NLR, LMR, and MHR for unfavorable functional outcome were 5.7, 4.2, and 1.5, respectively (p < 0.001, < 0.001, and 0.004, respectively). In multivariate analysis, NLR value ≥ 5.7 (odds ratio [OR] 1.92, 95% CI 1.42–3.42; P = 0.008), LMR value < 4.2 (OR 1.74, 95% CI 1.48–2.98; P = 0.018), and MHR value ≥ 1.5 (OR 1.44, 95% CI 1.22–2.82; P = 0.040) were independently associated with unfavorable functional outcome. Conclusion: Inflammation based scores were associated with functional outcome after endovascular intervention for aneurysmal SAH. Higher NLR and MHR with lower LMR could predict unfavorable outcomes of aneurysmal SAH patients who underwent endovascular intervention.

STUDY DESIGN This study was a retrospective review. OBJECTIVE The purpose of this study was to investigate the correlation analysis between Hounsfield units (HU) and dual x-ray absorptiometry (DXA) based on the clinical results of patients who underwent anterior cervical discectomy and fusion (ACDF) surgery. SUMMARY OF BACKGROUND DATA There is no technique to directly measure bone mineral density (BMD) in the cervical spine. As computed tomography is a very popular preoperative planning modality, using the HU value from that analysis to predict osteoporosis is important for patient outcomes and applications in the clinical field. MATERIALS AND METHODS We reviewed the records for 235 patients who underwent 1-level (n=120) or 2-level (n=115) ACDF surgery. In the 1-level ACDF group, the HU was measured from C3 to C6 vertebra, while that for the 2-level ACDF group was measured from 3 surgical index vertebrae. The correlation patterns were analyzed with the corresponding DXA (T-score) for each patient. Subsidence of fusion segment was defined as change in distance between plate-tip and upper (lower) margin of the vertebra (index level) after 4 months of follow-up. In addition, to determine the relevant factors that influence fusion segment subsidence, other preoperative (C2 slope, C7 slope, C2-C7 angle, and C2-C7 sagittal vertical axis) and postoperative parameters (coronal angle and segmental angle change) were measured. RESULTS The correlation coefficient between HU and DXA ranged from 0.57 to 0.71 in the 1-level ACDF group and from 0.59 to 0.66 in the 2-level ACDF group. The correlation between HU and DXA was statistically significant regardless of the degree of anterior osteophyte (r=-0.65 to 0.78). Total subsidence height was 3.8 mm after ACDF, and both HU and DXA were statistically correlated with total subsidence (r=0.26-0.28). In multivariate analysis, HU (middle vertebra) value was statistically associated with the degree of total subsidence. The high-subsidence group (≥4.5 mm) showed smaller HU values (284.1 vs. 316.0) and T-scores (-0.5 vs. 0.1) compared to the low-subsidence group (

Objective The low-profile Neuroform Atlas stent can be deployed directly without an exchange maneuver by navigating into the Gateway balloon. This retrospective study assessed the safety and efficacy of Neuroform Atlas stenting as a rescue treatment after failure of mechanical thrombetomy (MT) for large artery occlusion. Methods Between June 2018 and December 2019, a total of 31 patients underwent Neuroform Atlas stenting with prior Gateway balloon angioplasty after failure of conventional MT caused by residual intracranial atherosclerotic stenosis (ICAS). Primary outcomes were successful recanalization and patency of the vessel 24 hours after intervention. Secondary outcomes were vessel patency after 14 days and 3-month modified Rankin Scale. Peri-procedural complications, intracerebral hemorrhage (ICH), and 3-month mortality were reviewed. Results With a 100% of successful recanalization, median value of stenosis was reduced from 79.0% to 23.5%. Twenty-eight patients (90.3%) showed tolerable vessel patency after 14 days. New infarctions occurred in three patients (9.7%) over a period of 14 days; two patient (6.5%) underwent stent occlusion at 24 hours, and the other patient (3.2%) with delayed stent occlusion had a non-symptomatic dot infarct. There were no peri-procedural complications. Two patients (6.5%) developed an ICH immediately after the procedure with one of them is symptomatic. Conclusion Neuroform Atlas stenting seems to be an effective and safe rescue treatment modality for failed MT with residual ICAS, by its high successful recanalization rate with tolerable patency, and low peri-procedural complication rate. Further multicenter and randomized controlled trials are needed to confirm our findings.

The present study reports on the usefulness of FlowGate(2) (FG2) as a novel balloon guide catheter (BGC) for mechanical thrombectomy (MT) treatment. MT using a BGC device was performed on 255 patients at the authors' institution (St. Vincent's hospital, Suwon, Korea and Hangang Sacred Heart Hospital, Seoul, Korea) between January 2014 and September 2018. A total of 235 patients underwent successful application of BGCs and were divided into two groups; an FG2 and a Merci group, and a comparative analysis was performed. The failure rate in the FG2 group (2.5%) was significantly lower than that in the Merci group (10.8%; P=0.016). Occurrence of distal emboli was significantly lower in the FG2 group (4.7%) than in the Merci group (7.3%; P=0.012). According to subgroup analysis of the BGC and the intermediate catheter, the incidence rate of the distal emboli in the FG2 with an intermediate catheter (2.3%) was significantly lower than that of the Merci with an intermediate catheter (6.6%; P=0.038). The ratio of thrombolysis in cerebral infarction (TICI) 3 recanalization in the first pass was higher in the FG2 group than in the Merci group, in both total (44.7 vs. 34.7%; P=0.033) and subgroup patients (46.5 vs. 34.4%; P=0.029). In the multivariate analysis, use of an intermediate catheter [odds ratio (OR), 0.75; 95% confidence interval (CI), 0.66-0.94; P=0.029] and FG2 application (OR, 0.59; 95% CI, 0.25-0.93; P=0.020) were the predictive factors for fewer distal emboli. In summary, FG2 BGC enables an effective MT with less application failures and occurrence of distal emboli, and higher TICI 3 recanalization at the first stent passage, compared with Merci BGC.

The objective of this study was to assess the relationship between inflammation-based scores and prognosis of patients who had undergone mechanical thrombectomy (MT) for large artery occlusion.A total of 411 patients were enrolled and inflammation-based scores, such as neutrophil/lymphocyte ratio (NLR), lymphocyte/monocyte ratio (LMR), and monocyte/high-density lipoprotein cholesterol ratio (MHR) were calculated based on laboratory data. Prognoses were evaluated with unfavorable outcome (modified Rankin Scale score of 3-6), symptomatic intracranial hemorrhage, hemorrhagic transformation of infarct, and mortality. Multivariate analyses were performed to explore the relationships of inflammation-based scores with various clinical outcomes.Patients with unfavorable outcome showed higher mean NLR and MHR but lower mean LMR than those with favorable outcome (NLR, 7.32 vs. 3.78, P ≤ 0.001; MHR, 1.42 vs. 1.15, P = 0.012; LMR, 2.76 vs. 3.70, P = 0.003). In multivariate analysis, higher NLR (≥5.1) (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.04-2.12; P = 0.014) and higher MHR (≥1.4) (OR, 1.32; 95% CI, 1.10-1.74; P = 0.028), lower LMR (2.5) (OR, 1.28; 95% CI, 1.08-1.58; P = 0.032) were independently associated with unfavorable outcome.After MT, higher NLR, higher MHR, and lower LMR were found in patients with unfavorable outcome. Inflammation-based scores, such as NLR, LMR, and MHR, might be independent factors that can predict outcomes in patients with MT.

Background Pulling a retriever stent after several minutes of waiting time is a popular technique in mechanical thrombectomy with a stent retriever, but little data exist on the actual effects of waiting after stent deployment. Methods We conducted a multicenter retrospective study of consecutive 210 patients separated into 2 groups, a waiting after stent deployment group and a nonwaiting group. A comparative analysis was performed in terms of clinical and radiologic outcomes and complications with respect to multiple categories. Results There were no significant differences in baseline characteristics and clinical outcomes between the 2 groups. However, compared with the nonwaiting group, the waiting group had a higher rate of one-pass procedures, a lower mean number of stent passages, and a shorter procedure time (P = 0.021, 0.014, and 0.004, respectively). The proportion of patients with successful recanalization was also higher in the waiting group (P = 0.038). In multivariate analysis, waiting after stent deployment was a predictive factor for successful recanalization (odds ratio, 1.60; 95% confidence interval, 1.110–2.090; P = 0.02). Conclusions Waiting after stent deployment can lead to a more successful recanalization with a smaller number of stent passages and less distal emboli. More randomized controlled trials are needed to support these findings.

Background There are few studies assessing the suitable stent size for mechanical thrombectomy in middle cerebral artery (MCA) occlusion. We attempted to determine what size of stent is suitable for thrombectomy in MCA occlusion through a comparison of Trevo XP 6 × 25 mm and 4 × 20 mm stents. Methods We changed Trevo XP 4 × 20 mm stents to Trevo XP 6 × 25 mm stents for thrombectomy in MCA occlusion with the hypothesis that a larger stent would have better outcomes. Retrospectively, 87 patients were divided into 2 groups: the Trevo XP 6 × 25 mm stent group and Trevo XP 4 × 20 mm stent group, and a comparative study was performed in terms of clinical and radiologic outcomes and complications. Results The proportion of patients with a good clinical outcome and successful recanalization was higher in the Trevo XP 6 × 25 mm stent group than in the Trevo XP 4 × 20 mm stent group, with statistical significance (P = 0.041, P = 0.036). In multivariate analysis, the use of the Trevo 6 × 25 mm stent was a predictive factor for a good clinical outcome (odds ratio, 1.22; 95% confidence interval, 1.06–1.38; P = 0.03) and successful recanalization (odds ratio, 1.89; 95% confidence interval, 1.25–2.87; P = 0.018). However, there was no statistically significant difference in complications between the 2 groups. Conclusions Our study showed that the Trevo XP 6 × 25 mm stent provides better clinical and radiologic outcomes than the Trevo XP 4 × 20 mm stent for MCA occlusion without an increase in the rate of complications.

Objective Chronic subdural hematoma is a common and relatively benign disease. However, recurrence is common after surgical treatment, and the recurrence rate varies from 5% to 33%. The aim of this study was to investigate the predictive factors for recurrence of chronic subdural hematoma. Methods We analyzed data from 248 patients with chronic subdural hematoma who were treated by burr-hole craniostomy with a closed drainage system for hematoma evacuation in this five-year retrospective study. Results Thirty-one (12.6%) patients underwent re-operation for recurrence of chronic subdural hematoma. Univariate analysis revealed that anticoagulation (p=0.0279), headache (p=0.0323), and preoperative midline shifting (p=0.0321) showed significant differences with respect to recurrent chronic subdural hematoma. We performed a multivariate logistic regression analysis and found that diabetes mellitus (odds ratio [OR], 2.618; 95% confidence interval [CI], 1.0899-6.2898; p=0.0314), anticoagulation (OR, 6.739; 95% CI, 1.1287-40.2369; p=0.0364), headache (OR, 2.951; 95% CI, 1.1464-7.5964; p=0.0249), and preoperative midline shifting (OR, 1.0838; 95% CI, 1.0040-1.1699; p=0.0391) were independent predictive factors for recurrence of chronic subdural hematoma. Conclusion We showed that diabetes mellitus, anticoagulation, headache, and preoperative midline shifting were independent predictors of recurrence of chronic subdural hematoma.

Currently, endovascular coiling is a popular treatment for basilar tip aneurysms, which usually involve a wide neck. Serious complications can occur when the posterior cerebral artery (PCA) originating from a wide neck is not properly preserved. Accordingly, various adjunctive procedures using stents or a balloon have been introduced. Herein we report two cases of basilar tip aneurysms in which retrograde horizontal (from one PCA to the other PCA) stent-assisted coiling was successful, and we provide a summary of the important technical points.

The clinical benefit of endovascular stroke therapy has been demonstrated in several prospective randomized trials. However, in a relevant percentage of patients, mechanical thrombectomy bears the risk of causing new infarction in initially unaffected vascular territories through thrombus fragmentation and migration of clot debris. The goal of this study was to evaluate the use of the balloon guide catheter (BGC) to effectively achieve flow arrest and thrombus aspiration during the intervention to avoid distal embolization. A retrospective study was performed in 139 patients between October 2010 and May 2016 to analyze occlusions in the middle cerebral artery (MCA) or internal carotid artery (ICA) by using a stent retriever with a BGC (n = 73) or a non-BGC (n = 66). The following data were collected: patient age and gender, along with history of diabetes mellitus, hypertension, atrial fibrillation, smoking, obesity, dyslipidemia, and previous ischemic stroke. Data on procedure time, number of passes, and angiographic findings were also collected. The final reperfusion score was rated based on the Thrombolysis in Cerebral Infarction (TICI) grading scale. Successful recanalization was defined as TICI 3 or 2b. A total of 139 patients underwent mechanical thrombectomy with the stent retriever. Of the 139 patients, 73 (52.5%) underwent placement of a BGC. The mean age was 65.8 ± 13.5 years, and the median National Institutes of Health Stroke Scale (NIHSS) score was 11. The average initial NIHSS score was lower in the BGC group compared with the non-BGC group (mean, 11.2 ± 5.6 vs. 13.2 ± 5.6; P = 0.03). Patients with BGC had fewer incidences of previous ischemic stroke (12.3% vs. 28.8%; P = 0.01). The numbers of passes were similar between the two groups. The procedure time (99 ± 49.4 min vs. 124 ± 72.2 min; P = 0.02) and the time from onset of symptoms to procedure end (302 ± 102 min vs. 357.2 ± 136.1 min; P = 0.009) were shorter in the BGC group. TICI 3 or 2b recanalization scores were higher in the BGC group compared to the non-BGC group [63/73, 86.3% vs. 48/66, 72.7%; odds ratio (OR), 0.6; 95% confidence interval (CI), 0.2–1.4; P = 0.04]. Importantly, distal embolization was less frequent in the BGC group (5/73, 6.8% vs. 21/66, 31.8%; OR, 6.3; 95% CI, 2.2–18.0; P

Objective High frequency stimulation (HFS) of the subthalamic nucleus (STN) is recognized as an effective treatment of advanced Parkinson's disease. However, the neurochemical basis of its effects remains unknown. The aim of this study is to investigate the effects of STN HFS in intact and 6-hydroxydopamine (6-OHDA)-lesioned hemiparkinsonian rat model on changes of principal neurotransmitters, glutamate, and gamma-aminobutyric acid (GABA) in the striatum. Methods The authors examined extracellular glutamate and GABA change in the striatum on sham group, 6-OHDA group, and 6-OHDA plus deep brain stimulation (DBS) group using microdialysis methods. Results High-pressure liquid chromatography was used to quantify glutamate and GABA. The results show that HFS-STN induces a significant increase of extracellular glutamate and GABA in the striatum of 6-OHDA plus DBS group compared with sham and 6-OHDA group. Conclusion Therefore, the clinical results of STN-HFS are not restricted to the direct STN targets but involve widespread adaptive changes within the basal ganglia.

Objective: The safety and effect of intra-arterial (IA) tirofiban, a glycoprotein IIb/IIIa inhibitor, during the stent retriever mechanical thrombectomy (MT) was investigated. Methods: From January 2015 to May 2019, a total of 327 patients underwent mechanical thrombectomy of large artery occlusions (LAO). Patients were classified into two groups: MT with IA tirofiban (MTT) group and MT only (MTO, without IA tirofiban) group. Clinical outcomes, radiological results, and various complications, such as post thrombectomy hemorrhage, symptomatic hemorrhage, other systemic bleeding, and hemorrhagic transformation of infarct were evaluated by comparing the MTT group and MTO group. In addition, subgroup analysis was performed for patients who underwent MT with prior intravenous (IV) tissue plasminogen activator (t-PA). Results: The MTT group needed a lower mean number of stent passes and showed a re-occlusion rate as compared with the MTO group (P=0.038 and 0.022, respectively). Between the two groups, there were no statistically significant differences in post thrombectomy hemorrhage, symptomatic hemorrhage, other systemic bleeding complications, or hemorrhagic transformation of infarct (P = 0.511, 0.397, 0.429, and 0.355, respectively). In the subgroup analysis, similar findings were observed. Conclusion: The use of IA tirofiban during MT seems to be safe and potentially more effective than only MT without IA tirofiban, even in patients who used IV t-PA before MT.

Introduction Mechanical thrombectomy (MT) after intravenous thrombolysis (IVT) is recommended in acute ischemic stroke (AIS) patients with large artery occlusion (LAO). But in cases of ineligible for IVT, MT is the only option. The aim of this study is to evaluate the efficacy and outcome of MT in case of ineligible for IVT. Method Retrospective analysis was performed in consecutive patients treated between January 2016 and November 2018 for AIS with LAO. Patient demographic data were collected and clinical outcome, procedure details and complication rate were compared. Results During the period, 80 patients were visited within 4.5 hours from onset, but only 31 underwent MT alone due to contraindication (MT group). And 49 underwent MT combined IVT (MTIVT group). There was no significant difference in demographics and complication (distal emboli, mortality rate, symptomatic intracranial hemorrhage). The mean time from onset to groin puncture, successful reperfusion rate (defined thrombolysis in cerebral infarction 2b/3) and favorable functional outcome (determined by modified Rankin Scale score 0–2 at 90 days) also showed no significant statistically difference. But MT group had a significantly shorter mean procedure time (45.84 vs. 76.06 min; p = 0.001) and hospital stay (11.53 vs. 15.0 day; p = 0.042), and a lower 1-day NIHSS score (6.35 vs 10.88; p = 0.012). Conclusion In ineligible patient for IVT, MT alone isn’t inferior to MT combined with IVT. Disclosures J. Sung: None. M. Lee: None. D. Lee: None. H. Lee: None. S. Yang: None.