Improvement of cerebral blood flow after balloon angioplasty and stenting for symptomatic middle cerebral artery stenosis.

OBJECTIVE: Although reports of endovascular treatment for intracranial arterial stenosis have been increasing recently, their efficacy remains to be elucidated. This study aimed to investigate the changes in cerebral hemodynamics of severe middle cerebral artery (MCA) stenosis patients by performing CT perfusion (CTP) after endovascular treatment. METHODS: Subjects were those who underwent balloon angioplasty and stenting for symptomatic MCA M1 stenosis refractory to medical therapy at our hospital between 2008 and 2022. We included 36 patients (mean age 63.69 ± 15.24 years, 20 males) who underwent CTP before and within three weeks after treatment. The CTP parameters such as relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), and relative mean transit time (rMTT) were calculated as ipsilateral values divided by contralateral value. RESULTS: Endovascular treatment consisted of 26 balloon angioplasty and 10 stenting procedures performed at an average of 1 month from onset. CTP was performed at an average of 5.5 days postoperatively. The mean overall stenosis rate decreased from 79.0% to 30.3%. In the balloon angioplasty group, it decreased from 77.6% to 35.3%, and in the stent group, it decreased from 82.7% to 17.5%. After treatment, rCBF and rMTT measured by CTP improved significantly (both p < 0.001), whereas there was no significant change in rCBV. The improvement rates of rCBF and rMTT were mild higher in the stent group, but not significantly so. CONCLUSION: Balloon angioplasty and stenting for symptomatic MCA improved cerebral hemodynamics, resulting in significantly increased rCBF and decreased rMTT.

Ischemic stroke patients with low DWI ASPECTS scores require puncture to recanalization within 30 min for large vessel occlusion.

BACKGROUND: The clinical benefits of faster recanalization in acute large vessel occlusion are well recognized, but the optimal procedure time remains uncertain. The aim of this study was to identify patient characteristics that necessitate puncture-to-recanalization (P-R) time within 30 min to achieve favorable outcome. METHODS: We evaluated the patients from a prospective, multicenter, observational registry of acute ischemic stroke patients. The study included patients who underwent endovascular therapy for ICA or MCA M1 occlusion and achieved successful recanalization. Patients were categorized into subgroups based on pre-treatment characteristics and the frequency of favorable outcomes was compared between P-R time < 30 min and ≥ 30 min. Interaction terms were incorporated into the models to assess the correlation between each patient characteristic and P-R time. RESULTS: A total of 1053 patients were included in the study. Univariate analysis within each subgroup revealed a significant association between P-R < 30 min and favorable outcomes in patients with DWI ASPECTS ≤6, age > 85 and NIHSS ≥16. In the multivariable analysis, NIHSS, age, time from symptom recognition to puncture, and DWI ASPECTS were significant independent predictors of favorable outcomes. Notably, only DWI ASPECTS exhibited interaction terms with P-R < 30 min. The multivariable analysis indicated that P-R < 30 min was an independent predictor for favorable outcome in DWI ASPECTS ≤6 group, whereas not in DWI ≥7. CONCLUSIONS: P-R time < 30 min is predictive of favorable outcomes; however, the effect depends on DWI ASPECTS. Target P-R time < 30 min is appropriate for patients with DWI ASPECTS ≤6.

Primary results of mechanical thrombectomy for acute ischemic stroke: The K-NET registry in the Japanese metropolitan area.

BACKGROUND: Endovascular treatment (EVT) for acute large vessel occlusion has proven to be effective in randomized controlled trials. We conducted a prospective cohort study to evaluate the real-world efficacy of EVT in a metropolitan area with a large number of comprehensive stroke centers and to compare it with the results of other registries and randomized controlled trials (RCTs). METHODS: We analyzed the Kanagawa Intravenous and Endovascular Treatment of Acute Ischemic Stroke registry, a prospective, multicenter observational study of patients treated by EVT and/or intravenous tissue-type plasminogen activator (tPA). Of the 2488 patients enrolled from January 2018 to June 2020, 1764 patients treated with EVT were included. The primary outcome was a good outcome, which was defined as a modified Rankin Scale (mRS) of 0-2 at 90 days. Secondary analysis included predicting a good outcome using multivariate logistic regression analysis. RESULTS: The median age was 77 years, and the median National Institute of Health Stroke Scale (NIHSS) score was 18. Pretreatment mRS score 0-2 was 87%, and direct transport was 92%. The rate of occlusion in anterior circulation was 90.3%. Successful recanalization was observed in 88.7%. The median time from onset to recanalization was 193 min. Good outcomes at 90 days were 43.3% in anterior circulation and 41.9% in posterior circulation. Overall mortality was 12.6%. Significant predictors for a good outcome were as follows: age, male, direct transfer, NIHSS score, Alberta Stroke Program Early Computed Tomography Score, intravenous tPA, and successful recanalization. CONCLUSION: EVT in routine clinical use in a metropolitan area showed comparable good outcomes and lower mortality compared to previous studies, despite the high proportion of patients with older age, pretreatment mRS score of >2, posterior circulation occlusion, and higher NIHSS. Those results may have been associated with more direct transport and faster onset-to-recanalization times.

Long-term outcome and factors associated with restenosis after combination therapy of balloon angioplasty and stenting for symptomatic intracranial stenosis.

BACKGROUND: The optimal treatment for intracranial artery stenosis (ICAS) has not been established. We retrospectively examined the initial and long-term outcomes associated with restenosis of a combination therapy of balloon angioplasty and stenting for symptomatic atherosclerotic ICAS. METHODS: Consecutive patients who underwent balloon angioplasty and/or stenting for ≥ 70% ICAS between 2006 and 2020 were analyzed. Patients within 48 h of stroke onset were excluded. The following procedures were established as standards at our institution: (1) primary balloon angioplasty alone was initially performed; (2) stenting for insufficient dilatation, recoiling, or dissection was conducted; and (3) stenting was considered for restenosis. Intracranial ischemic and hemorrhagic complications within 30 days after treatment were used to evaluate periprocedural safety. Recurrent ischemic events, restenosis and restenosis related factors were used to be evaluate the long-term outcome. RESULTS: A total of 160 patients were recruited. Initial treatment consisted of balloon angioplasty (n = 101) and stenting (n = 59). Intracranial complications within 30 days after treatment were ischemic in five (3.1%) and hemorrhagic in four patients (2.5%). The incidence of these complication was 3.1% in the stenting group and 2.5% in the balloon angioplasty group. The mean follow-up period was 53.9 months. Restenosis was found in 42 patients (26%). Recurrent ischemic events during follow-up were noted in 14 patients (8.8%), of which six patients had TIA and eight patients had ischemic stroke. Restenosis-associated factors included diabetes, coronary artery disease, percent stenosis after treatment, and balloon angioplasty in logistic univariate analysis. Multivariate Cox regression analysis showed that diabetes (HR: 2.084, CI: 1.039-4.180, p = 0.0386), length of lesion (HR; 1.358, CI: 1.174-1.571, p < 0.0001), and balloon angioplasty (HR: 4.194, CI: 1.083-16.239, p = 0.0379) were independent predictors for restenosis. CONCLUSION: Combination therapy of balloon angioplasty and stenting for symptomatic ICAS had a low perioperative stroke rate and may improve long-term outcome. Balloon angioplasty, diabetes, and length of lesion were significantly associated with restenosis.

The Influence of Experience on Gazing Patterns during Endovascular Treatment: Eye-Tracking Study.

Objective: In various fields, differences in eye-gazing patterns during tasks between experts and novices have been evaluated. The aim of this study was to investigate gazing patterns during neuro-endovascular treatment using an eye-tracking device and assess whether gazing patterns depend on the physician's experience or skill. Methods: Seven physicians performed coil embolization for a cerebral aneurysm in a silicone vessel model under biplane X-ray fluoroscopy, and their gazing patterns were recorded using an eye-tracking device. The subjects were divided into three groups according to experience, highly experienced (Expert) group, intermediately experienced (Trainee) group, and less experienced (Novice) group. The duration of fixation on the anterior-posterior (AP) view screen, lateral (LR) view, and out-of-screen were compared between each group. Results: During microcatheter navigation, the Expert and Trainee groups spent a long time on fixation to AP, while the Novice group split their attention between each location. In coil insertion, the Expert group gazed at both the AP and the LR views with more saccades between screens. In contrast, the Trainee group spent most of their time only on the AP view screen and the Novice group spent longer out-of-screen. Conclusion: An eye-tracking device can detect different gazing patterns among physicians with several experiences and skill levels of neuroendovascular treatment. Learning the gazing patterns of experts using eye tracking may be a good educational tool for novices and trainees.

A Case Report of Contrast-Induced Encephalopathy after Repeated Percutaneous Transluminal Angioplasty for Acute Middle Cerebral Artery Occlusion.

Objective: We report a case of contrast-induced encephalopathy (CIE) after repeated percutaneous transluminal angioplasty (PTA) for acute middle cerebral artery (MCA) occlusion. Case Presentation: An 88-year-old woman with left hemiparesis was transferred to our hospital by ambulance. MRI revealed acute MCA M1 occlusion. We performed intravenous tissue plasminogen activator therapy and PTA for right MCA occlusion, leading to complete recanalization and improvement in hemiparalysis. After approximately one week, restenosis of right MCA developed and PTA was performed again on day 11. However, her left hemiparesis exacerbated shortly thereafter. CT demonstrated leakage of contrast medium, and an extensive high-intensity area (HIA) on the white matter in the right cerebral hemisphere was noted on MRI FLAIR. The HIA on MRI and neurological deficits gradually improved after conservative treatment, but diffuse atrophy of the right cerebral hemisphere occurred and higher brain dysfunction remained. Conclusion: Repeated ischemia and reperfusion, and the frequent use of contrast media were considered the causes of CIE.

Outcomes of Balloon Angioplasty and Stenting for Symptomatic Intracranial Atherosclerotic Stenosis at a High Volume Center.

PURPOSE: This study investigated the periprocedural complication rates, long-term outcome, and restenosis of endovascular treatment for intracranial atherosclerotic stenosis (ICS) at our hospital. METHODS: We retrospectively analyzed the clinical data of 217 patients comprising 256 endovascular treatments for high-grade symptomatic ICS. The lesion was located in the internal carotid artery in 77, the middle cerebral artery in 111, the basilar artery in 29, and the vertebral artery in 39. Patients were divided into two groups, before (early-phase group, 1999-2013) and after approval of Wingspan (late-phase group, 2014-2017). RESULTS: In the early-phase group (n = 163), 157 lesions were treated by balloon angioplasty and 31 (17%) by coronary stenting. In the late-phase group (n = 54), 33 lesions were treated by balloon angioplasty and 35 (52%) by Wingspan stenting. Overall technical success rates were 96% in the balloon angioplasty and 100% in stenting groups. The 30-day rate of stroke, TIA, and death were 4.8% in the early-phase group and 4.4% in the late-phase group. There was one minor stroke and two TIAs during the follow-up period in the late-phase group. CONCLUSIONS: Endovascular treatment for symptomatic ICS in this study appeared to be safe and effective if patients are properly selected. However, future well-designed randomized trials with different techniques and modified patients selection criteria are certainly warranted.

Successful Endovascular Thrombectomy for Acute M1 Occlusion in a Patient with Situs Inversus: A Case Report.

Situs inversus is a rare congenital anomaly which has the mirror image of systemic organs and vessels from their normal position. We report a case of endovascular thrombectomy for acute middle cerebral artery (MCA) M1 occlusion in a patient with complete situs inversus. A right-handed man in his 70s presented to our hospital with loss of consciousness, right-sided hemiplegia, and total aphasia. Endovascular thrombectomy was undertaken for left M1 occlusion. Guide catheter advanced through right aortic arch and injection showed innominate artery was on the left side. Left common carotid artery arose from left innominate artery. Using aspiration catheter and stent retriever, successful recanalization was achieved after three passes. For treatment of acute stroke with large vessel occlusion in patients with situs inversus, understanding anatomy and clinical features of situs inversus is important.

A Case of Acute Ischemic Stroke Treated with Endovascular Treatment for Tandem Occlusion of the Common Carotid Artery and Internal Carotid Artery Terminal Portion Related to Takayasu Arteritis.

Objective: This report presents a case of mechanical thrombectomy for left internal carotid artery (ICA) terminal portion occlusion performed by left common carotid artery recanalization during hospitalization after diagnosing bilateral common carotid artery occlusion due to Takayasu arteritis. Case Presentation: A 25-year-old woman with fever and cervix pain a few months ago visited our department after repeated transient aphasic attacks. Magnetic resonance imaging (MRI) demonstrated diffuse infarction in the left middle cerebral artery (MCA) area, and she was diagnosed with Takayasu arteritis due to bilateral common carotid artery occlusion and left subclavian artery stenosis. On the 20th day of hospitalization, the terminal portion of the left ICA was occluded and thrombectomy was performed after balloon dilation of the left common carotid artery. Lastly, left common carotid artery stenting was performed. Aphasia and sensory disturbance remained, but she was transferred to a rehabilitation hospital with a modified Rankin Scale (mRS) of 2 on the 65th day of hospitalization. Antithrombotic and immunosuppressive therapy were performed, and restenosis did not develop. Conclusion: Angioplasty and stenting of common carotid artery occlusion can be effective treatments in thrombectomy for intracranial occlusion due to Takayasu disease.

Preprocedural Carotid Plaque Echolucency as a Predictor of In-Stent Intimal Restenosis after Carotid Artery Stenting.

OBJECTIVES: In-stent intimal restenosis (ISR) caused by neointimal hyperplasia can develop <24 months after carotid artery stenting (CAS). The utility of plaque imaging by carotid ultrasonography (US) or magnetic resonance imaging (MRI) has been investigated for the prediction of ipsilateral stroke. We aimed to investigate whether these imaging techniques are useful for detecting carotid plaques prone to ISR. MATERIALS AND METHODS: We examined 133 patients (mean age of 72.1 ± 8.4 years old) that received CAS at a single hospital from 2014 to 2018. A pre-CAS carotid plaque evaluation was performed by carotid angiography, duplex carotid US, and black-blood carotid artery MRI (BB-MRI). The mean stenosis rate was 71.0 ± 12.3% by the North American Symptomatic Carotid Endarterectomy Trial (NASCET) methods. Follow-up carotid angiography was performed 6 months after CAS in all patients according to a predefined protocol. ISR was defined as in-stent intimal hyperplasia more than 50% stenosed based on the NASCET criteria. The selection of the stent type was at the discretion of the treating physician. Predictors of ISR were determined by multivariate logistic regression analysis. RESULTS: Follow-up angiography demonstrated ISR in 33 patients (24.8%). In 44 patients, more than two stents were deployed. Univariate logistic regression analyses demonstrated echolucent lesion, floating plaque, complete occlusive or pseudo-occlusive lesion, and closed-cell stent use as significantly associated with ISR (>50%). Multivariate logistic regression analysis demonstrated that echolucent lesion (OR 4.667, 95% CI 1.849-11.779) and closed-cell stent use (OR .378, 95% CI .148-.968) were significantly associated with ISR. CONCLUSIONS: Preprocedural plaque characterization by carotid US appeared to be useful to predict ISR 6 months after CAS.

Effects of Aspiration and Re-transfusion Technique with Carotid Artery Stenting.

Objective: Embolic stroke is the most serious complication after carotid artery stenting (CAS). The incidence rate of embolic stroke is reduced by the use of embolic protection devices (EPDs); however, there is no consensus on which EPD is the most effective. The aspiration and re-transfusion technique (ART) with CAS under distal balloon protection was adopted at our center to reduce the incidence of embolic complications. This retrospective study investigated the effects of ART. Methods: From November 2010, 243 consecutive patients treated by CAS under distal balloon protection were included. ART was performed on 202 patients (ART group) and the other 40 patients only received distal balloon protection (non-ART group). In ART, the blood from the aspiration catheter was continuously returned through a filter to the femoral vein. The amount of debris was assessed intermittently using a small blood sample and the rest was returned. We investigated the diffusion-weighted imaging (DWI)-positive rate and symptomatic ischemic stroke one day after CAS. Results: Compared with the non-ART group, the incidence of DWI-positive lesions (22.7% vs 37.5%, P = 0.07) and frequency of symptomatic ischemic stroke (0.9% vs 5.0%, P = 0.12) were reduced in the ART group. The hemoglobin reduction rate was significantly reduced by ART (11.1% vs 14.9%, P <0.01). In the ART group, the frequency of multiple lesions (more than 5) and large lesions (more than 10 mm) was lower than that in the non-ART group (P <0.01, P = 0.14). Conclusion: CAS under distal balloon protection with ART was effective at reducing the incidence of DWI-positive lesions and may be useful to reduce the incidence of symptomatic ischemic stroke.

Discrepancy in T1 and T2 shortening of the globus pallidus in hepatic insufficiency: evaluation by susceptibility-weighted imaging.

PURPOSE: We assessed the signal of the globus pallidus (GP) in cases of hepatic insufficiency, especially to evaluate the degree of discrepancy in paramagnetic effects on shortening of T(1) and T(2)* using susceptibility-weighted images (SWI). MATERIALS AND METHODS: Seven patients with hepatic insufficiency underwent magnetic resonance (MR) examinations that included T(1)-weighted images (T(1)WI), T(2)-weighted images (T(2)WI), and SWI on a 1.5-tesla MR imager, and we compared their results to those of controls. On T(1)WI and T(2)WI, we measured signal intensity in the GP and posterior segment of the putamen (Put) to obtain a signal ratio (GP/Put ratio), and on SWI, we classified signal intensity into 4 grades: A, higher than the cortex; B, lower than the cortex and higher than the cerebrospinal fluid (CSF); C, lower than the CSF and higher than the red nucleus; and D, lower than the red nucleus. RESULTS: In the 7 patients with hepatic insufficiency, the mean GP/Put ratio was significantly higher on T(1)WI and T(2)WI than those values in controls. On SWI, we classified 2 cases each as Grade A, Grade B, and Grade C, and one as Grade D. Although the signal of the GP was elevated on T(1)WI, there was no decrease in signal on T(2)WI. On SWI, we obtained no low signal intensity. CONCLUSION: In patients with hepatic insufficiency, the globus pallidus did not show low signal intensity on either T(2)WI or SWI. Hyperintensity of the GP on T(1)WI without hypointensity on T(2)WI, or even SWI, suggests a discrepancy between paramagnetic effect on T(1) and T(2) shortening that reflects the accumulation of manganese and the presence of hepatic insufficiency.