Intraprocedural Plaque Protrusion during Carotid Artery Stenting with a CASPER Stent: A Case Report.

Objective: Plaque protrusion (PP) during carotid artery stenting (CAS) is considered to be associated with periprocedural ischemic stroke. A new double-layer micromesh stent, the CASPER stent (CS), was approved for use in Japan in 2020. The expectation is that this micromesh stent system will reduce the risk of PP, but we report a case of PP during CAS despite the use of a CS. Case Presentation: An 87-year-old man presented with left hemiparesis. MRI showed right brain infarction and angiography showed right internal carotid artery stenosis with thrombus. Follow-up angiography after medical treatment showed that thrombus disappeared. We therefore performed CAS for right internal carotid artery stenosis with unstable plaque. CAS was performed under local anesthesia with Mo.Ma Ultra and FilterWire EZ protection using a CS placed to sufficiently cover the stenotic region. Conservative post-dilatation was then performed. Intravascular ultrasonography (IVUS) after post-dilatation showed the presence of PP. A second CS was then added using the stent-in-stent technique. No postoperative neurological abnormalities were found and the patient was discharged without postoperative complications. No stroke or restenosis has been observed as of 16 months after CAS. Conclusion: PP can occur even when CAS is performed using the CS for carotid artery stenosis with unstable plaque. The importance of checking for PP using IVUS is suggested.

Symptomatic Intracranial Hemorrhage after Mechanical Thrombectomy - the Difference between Iso-Osmolar and Low-Osmolar Contrast Media.

Objective: Symptomatic intracranial hemorrhage (SICH) after mechanical thrombectomy (MT) is generally considered a critical complication. Hemorrhagic transformation after ischemic stroke has also been associated with contrast media administration. The objective of our study was to evaluate correlations between contrast media type and incidence of SICH after MT. Methods: Ninety-three consecutive patients (41 men; mean age, 80.2 years; range, 44-98 years) underwent MT reperfusion (expanded thrombolysis in cerebral infarction score, 2a-3) for acute large-vessel occlusion ischemic stroke within 8 h after symptom onset between April 2020 and July 2023 were retrospectively reviewed. Correlations between contrast media type (iso-osmolar or low-osmolar medium) and incidence of SICH were assessed. Results: Contrast media were iso-osmolar in 60 cases or low-osmolar in 33 cases. The overall incidence of SICH was 5.5%. The frequency of SICH was significantly lower in the iso-osmolar group (1.7%) than in the low-osmolar group (12.1%; P = 0.033). Conclusion: Iso-osmolar contrast media was associated with a lower incidence of SICH compared with low-osmolar contrast media in patients after MT.

Carotid Artery Stenting for Near Occlusion with Full Collapse.

OBJECTIVE: Carotid near occlusions show a lower risk of stroke than other types of severe stenosis. However, emerging evidence suggests that near occlusion with full collapse differs from that without full collapse. The results of treatment with carotid artery stenting for near occlusion with full collapse are presented. METHODS: Between March 2007 and December 2020, 18 of 477 carotid artery stenting procedures were performed in patients with near occlusion with full collapse (3.8%). A total of 17 men and one woman with a mean age of 76.1 years were included. Eleven patients (61%) were symptomatic. The technical success rate, incidence of symptomatic stroke within 30 days, new ipsilateral ischemic lesions on diffusion tensor imaging within 48 hours after carotid artery stenting, and follow-up results (ipsilateral stroke rate and restenosis rate) were retrospectively assessed. RESULTS: The technical success rate was 100%. All carotid artery stenting procedures were performed using embolic protection devices. No symptomatic stroke occurred within 30 days. New ipsilateral ischemic lesions on magnetic resonance imaging were observed in 16.7% (3/18) of patients. Asymptomatic minor cerebral hemorrhage occurred in 2 patients (11.1%) with cerebral hyperperfusion syndrome. The median follow-up period was 77 months. Asymptomatic restenosis of 50% occurred in one patient (5.5%), and asymptomatic occlusion occurred in one patient (5.5%). During follow-up, no patients experienced ipsilateral stroke. Three patients (16.7%) died from nonneurological causes. CONCLUSIONS: Carotid artery stenting for near occlusion with full collapse seems to be a feasible and safe procedure that can be performed by an experienced neuro-interventional team.

A Case of Intraprocedural Plaque Protrusion during Carotid Artery Stenting Using the Stent-in-Stent Technique for Carotid Artery Stenosis with Unstable Plaque.

Objective: Carotid artery stenting (CAS) using the stent-in-stent technique was reported to prevent intraprocedural plaque protrusion (PP) in patients with carotid artery stenosis with unstable plaque. We report a case of intraoperative PP after CAS despite the use of stent-in-stent technique. Case Presentation: A 63-year-old man presented with rapid progression of right carotid artery stenosis with unstable plaque during follow-up and was admitted to undergo CAS. Under local anesthesia with Mo.Ma Ultra and FilterWire EZ protection, CAS was performed using the stent-in-stent technique. The first 8 mm × 29 mm Carotid Wallstent (CWS) was placed. The second CWS (6 mm × 22 mm) was placed in a stent-in-stent manner to match the stenotic lesion, and conservative postdilation was performed. Then the third CWS (6 mm × 22 mm) was added due to the presence of PP on intravascular ultrasonography (IVUS). No postoperative neurological abnormalities were found, and no new high-signal areas were observed on diffusion-weighted MRI the day after surgery. The patient was discharged without postoperative complications. No stroke and restenosis were observed at 3 months after CAS. Conclusion: PP can occur even with stent-in-stent technique, suggesting the importance of diagnosis by IVUS.

Hypocapnia Induced by Hyperventilation with Indocyanine Green Kinetics Detects the Effect of Staged Carotid Angioplasty to Avoid Hyperperfusion in Patients with Impaired Cerebral Hemodynamic Reserve.

Cerebral hyperperfusion syndrome (CHS) is a serious complication following carotid artery stenting (CAS). Staged angioplasty (AP) could potentially prevent CHS and hyperperfusion phenomenon (HPP) after revascularization. However, methods for measuring the effects of staged AP on cerebral hemodynamic reserve have not been established. Here, we evaluated whether indocyanine green kinetics and near-infrared spectroscopy (ICG-NIRS) with hypocapnia induced by hyperventilation can detect the effects of staged AP on hemodynamic reserve to prevent CHS after CAS. Participants comprised 44 patients at high risk of CHS, whose ipsilateral cerebrovascular reactivity (CVR) was impaired on preoperative single photon emission computed tomography (SPECT). Patients were divided into a staged AP group (n=13) and a regular CAS group (n=31). In the staged AP group, stenting was performed 3 weeks after staged AP. In the regular CAS group, 16 cases (52%) showed HPP, and five (16%) presented with CHS after CAS, while no HPP or CHS occurred in the staged AP group (p=0.001). Changes in blood flow index (BFI) and time to peak (TTP) ratio during hypocapnia calculated from ICG-NIRS indicated a significant linear relationship with preprocedural CVR on SPECT (r=-0.710, 0.632, respectively; p<0.0001 each). BFI and TTP ratios during hypocapnia were significantly improved after staged AP (p<0.001 each). Furthermore, significant linear correlations were observed between BFI and TTP ratio during hypocapnia and postoperative asymmetry index AI (r=0.405, -0.475, respectively; p<0.01 each). Hypocapnia induced by hyperventilation under ICG-NIRS appears useful for detecting the effects of staged AP on hemodynamic reserve in patients at high risk of CHS.

Low relative diffusion weighted image signal intensity can predict good prognosis after endovascular thrombectomy in patients with acute ischemic stroke.

BACKGROUND: It is vital to identify a surrogate last-known-well time to perform proper endovascular thrombectomy in acute ischemic stroke; however, no established imaging biomarker can easily and quickly identify eligibility for endovascular thrombectomy and predict good clinical prognosis. OBJECTIVE: To investigate whether low relative diffusion-weighted imaging (DWI) signal intensity can be used as a predictor of good clinical outcome after endovascular thrombectomy in patients with acute ischemic stroke. METHODS: We retrospectively identified consecutive patients with acute ischemic stroke who were treated with endovascular thrombectomy within 24 hours of the last-known-well time and achieved successful recanalization (modified Thrombolysis in Cerebral Infarction score ≥2b). Relative DWI signal intensity was calculated as DWI signal intensity in the infarcted area divided by DWI signal intensity in the contralateral hemisphere. Good prognosis was defined as a modified Rankin Scale score of 0-2 at 90 days after stroke onset (good prognosis group). RESULTS: 49 patients were included in the analysis. Relative DWI signal intensity was significantly lower in the group with good prognosis than in the those with poor prognosis (median (IQR) 1.32 (1.27-1.44) vs 1.56 (1.43-1.66); p<0.01), and the critical cut-off value for predicting good prognosis was 1.449 (area under the curve 0.78). Multiple logistic regression analysis revealed association of good prognosis after endovascular thrombectomy with low relative DWI signal intensity (OR=6.84; 95% CI 1.13 to 41.3; p=0.04). CONCLUSIONS: Low relative DWI signal intensity was associated with good prognosis after endovascular thrombectomy. Its ability to predict good clinical outcome shows potential for determining patient suitability for endovascular thrombectomy.

Endovascular therapy for cerebral infarction due to Trousseau syndrome in a patient with non-small cell lung cancer.

We describe a case of Trousseau's syndrome in a patient with lung carcinoma. A 69-year-old man presented with pleural effusion. Further evaluation revealed EGFR mutation-positive non-small cell carcinoma in the upper lobe with extensive lymph node, bone, and brain metastases. Administration of osimertinib, an EGFR tyrosine kinase inhibitor, resulted in partial tumor response, but caused osimertinib-induced pneumonitis 10 weeks later. Prednisolone restrained lung injury progression and was gradually tapered. However, he presented with impaired consciousness and right hemiplegia. Magnetic resonance imaging revealed a left middle cerebral artery M1 segment occlusion. D-dimer level was elevated to 19.5 µg/mL. In the absence of atherosclerotic or cardiogenic thrombi, these findings led to the diagnosis of Trousseau syndrome. Endovascular therapy, but not tissue plasminogen activator, improved his condition with no recurrences. These treatment strategies are crucial to restore function in patients with potentially disabling cerebral infarction due to Trousseau syndrome.

Treatment of Coral Reef Aorta by Endovascular VIABAHN VBX Balloon-Expandable Stent-Graft Placement.

Coral reef aorta (CRA) has been described as a rare disease characterized by the presence of dense calcifications of the aorta. In this study, we report on two patients with CRA caused by intermittent claudication (IC) who underwent endovascular VIABAHN VBX balloon-expandable stent-graft (VVBX) placement. Both patients underwent successful endovascular VVBX placement via transfemoral artery approach, and hemostasis was achieved via vascular closure device. Their symptoms were observed to disappear completely after treatment, and they were discharged without serious adverse events. No symptoms were noted at 1.5-year and 1-year follow-up.

Remarkable shrinkage of a thrombosed giant aneurysm by stent-assisted jam-packed coil embolization.

BACKGROUND: Large and giant aneurysms are known to involve intra-aneurysmal thrombosis and present a poor prognosis because of compression of the surrounding brain tissue with enlargement of the aneurysm. These aneurysms are difficult to cure by endovascular treatment due to involvement of the vasa vasorum in their pathology. We report this technical note to describe stent-assisted jam-packed coil embolization for the treatment of a giant thrombosed aneurysm. CASE DESCRIPTION: A 62-year-old man presented with right homonymous hemianopsia, and magnetic resonance imaging (MRI) showed a giant thrombosed aneurysm with poor wall contrast enhancement, which indicates little involvement of the vasa vasorum, at the terminal part of the left internal carotid artery. To block blood flow into the aneurysmal dome, stent-assisted "jam-packed" coil embolization was performed. For this, a braided stent was shortened to enhance metal coverage ratio and tight aneurysmal coil packing was performed using a hydrogel coil. Our technique resulted in complete obliteration of the aneurysm, and MRI performed 1 year later showed remarkable shrinkage of the aneurysm dome. CONCLUSION: Stent-assisted jam-packed coil embolization technique might be effective in shrinking the dome of giant thrombosed aneurysms with poor wall contrast enhancement.

Lipid Core Burden Index Assessed by Near-Infrared Spectroscopy of Symptomatic Carotid Plaques: Association with Magnetic Resonance T1-Weighted Imaging.

INTRODUCTION: Vulnerable plaques are a strong predictor of cerebrovascular ischemic events, and high lipid core plaques (LCPs) are associated with an increased risk of embolic infarcts during carotid artery stenting (CAS). Recent developments in magnetic resonance (MR) plaque imaging have enabled noninvasive assessment of carotid plaque vulnerability, and the lipid component and intraplaque hemorrhage (IPH) are visible as high signal intensity areas on T1-weighted MR images. Recently, catheter-based near-infrared spectroscopy (NIRS) has been shown to accurately distinguish LCPs without IPH. This study aimed to determine whether the results of assessment of high LCPs by catheter-based NIRS correlate with the results of MR plaque imaging. METHODS: We recruited 82 consecutive symptomatic carotid artery stenosis patients who were treated with CAS under NIRS and MR plaque assessment. Maximum lipid core burden index (max-LCBI) at minimal luminal areas (MLA), defined as max-LCBIMLA, and max-LCBI for any 4-mm segment in a target lesion, defined as max-LCBIAREA, were assessed by NIRS. Correlations were investigated between max-LCBI and MR T1-weighted plaque signal intensity ratio (T1W-SIR) and MR time-of-flight signal intensity ratio (TOF-SIR) in the same regions as assessed by NIRS. RESULTS: Both T1W-SIRMLA and T1W-SIRAREA were significantly lower in the high LCP group (max-LCBI >504, p < 0.001 for both), while TOF-SIRMLA and TOF-SIRAREA were significantly higher in the high LCP group (p < 0.001 and p = 0.004, respectively). A significant linear correlation was present between max-LCBIMLA and both TIW-SIRMLA and TOF-SIRMLA (r = -0.610 and 0.452, respectively, p < 0.0001 for both). Furthermore, logistic regression analysis revealed that T1W-SIRMLA and TOF-SIRMLA were significantly associated with a high LCP assessed by NIRS (OR, 44.19 and 0.43; 95% CI: 6.55-298.19 and 0.19-0.96; p < 0.001 and = 0.039, respectively). CONCLUSIONS: A high LCP assessed by NIRS correlates with the signal intensity ratio of MR imaging in symptomatic patients with unstable carotid plaques.

Active management of the target P2Y12 reaction unit range in patients undergoing stent-assisted coil embolization for unruptured cerebral aneurysms.

BACKGROUND: Platelet function tests have been increasingly adopted to measure patient responses to antiplatelet drugs, and to predict complications. However, no established optimal antiplatelet management for stent-assisted coil embolization (SAC) have been established. The purpose of the present study was to investigate the efficacy and feasibility of clopidogrel dose adjustment for active target P2Y12 reaction unit (PRU). METHODS: A total of 202 consecutive patients undergoing SAC to treat unruptured intracranial aneurysms were prospectively recruited. All patients were given two antiplatelet agents starting 7 days prior to the procedure, and platelet function was measured with the VerifyNow test. Clopidogrel hyper-responsive patients received reduced dosing according to the values of follow-up PRUs before and 7, 14, 30, and 90 days after the procedure. Patients were divided into three groups according to clopidogrel responsiveness before treatment, and clinical outcomes and time in target PRU ranges (TTR) were analyzed. RESULTS: No delayed ischemic or hemorrhagic events occurred that were associated with out-of-range PRU. PRU values in the hypo-responsive and hyper-responsive groups significantly improved 7 days after treatment with active target PRU management (p=0.05,<0.001, respectively). PRU values were controlled within the target PRU range with drug adjustment (p=0.034), and the time in TTR for all patients was 97% (4.8%-100%), which showed the feasibility of optimal control of PRU values with the protocol. CONCLUSION: Active target PRU management can achieve control of optimal PRU values and may decrease perioperative ischemic and hemorrhagic events among patients undergoing SAC.

Carotid Artery Stenting Using a Closed-Cell Stent-in-Stent Technique for Unstable Plaque.

Purpose: To examine whether carotid artery stenting (CAS) of stenoses with unstable plaque using a closed-cell stent-in-stent technique prevents plaque protrusion. Materials and Methods: Between December 2014 and August 2018, 35 consecutive patients (mean age 75.8 years; 29 men) with carotid artery stenosis (20 symptomatic) and unstable plaque diagnosed by magnetic resonance imaging were prospectively analyzed. Mean diameter stenosis was 83.5%. All CAS procedures were performed with stent-in-stent placement of Carotid Wallstents using an embolic protection device and conservative postdilation. The technical success rate, incidence of plaque protrusion, ischemic stroke rate within 30 days, and new ipsilateral ischemic lesions on diffusion-weighted imaging (DWI) within 48 hours after CAS were prospectively assessed. Follow-up outcomes included the incidences of ipsilateral stroke and restenosis. Results: The technical success rate was 100%. No plaque protrusion or stroke occurred in any patient. New ischemic lesions were observed on DWI in 10 (29%) patients. During the mean 11.6-month follow-up, no ipsilateral strokes occurred. Two (6%) patients developed asymptomatic restenosis recorded as 53% lumen narrowing and occlusion, respectively. Conclusion: CAS using a closed-cell stent-in-stent technique for unstable plaque may be useful for preventing plaque protrusion and ischemic complications.

Carotid Artery Stenting: Investigation of Plaque Protrusion Incidence and Prognosis.

OBJECTIVES: This study sought to clarify the incidence and prognosis of PP in carotid artery stenting (CAS). BACKGROUND: Projections thought to be plaque may be observed inside the stent on angiography or intravascular ultrasound (IVUS) during CAS. Known as plaque protrusion (PP), the incidence and prognosis of this complication are unclear. METHODS: A total of 354 consecutive carotid atherosclerotic stenoses in 328 patients (285 men, 43 women; age range 51 to 97 years [mean age 73.6 years]; 158 symptomatic cases; stenosis rate, 50% to 99% [mean 81.0%]) who underwent CAS under IVUS between October 2007 and March 2016 were retrospectively analyzed. PP was defined as plaque seen inside the stent lumen on both digital subtraction angiography and IVUS. The incidence and prognosis (rate of stroke within 30 post-operative days) of PP and the rate of ischemic lesions on the treated side on diffusion-weighted imaging performed within 48 post-operative hours within the PP group were investigated. RESULTS: PP was observed in 9 cases (2.6%). Ischemic stroke occurred in 6 of 9 PP cases (66.7%; 1 major, 5 minor). Ischemic lesions were observed on diffusion-weighted imaging in 8 of 9 cases (88.9%). PP was strongly associated with perioperative ischemic stroke. A significant increase in PP susceptibility was observed with open-cell stent use and unstable plaque. CONCLUSIONS: The incidence of PP in CAS was 2.6%, with a high risk of ischemic complications if PP was observed. The present findings indicate the necessity of appropriate device selection to avoid PP.

Stent Placement for Severe Stenosis of the Left Common Carotid Artery with Internal-to-External Carotid Steal.

We report the case of a 64-year-old male with internal carotid artery (ICA)-to-external carotid artery (ECA) steal due to severe stenosis of the common carotid artery (CCA). Left CCA occlusion was initially diagnosed on 3-dimensional time-of-flight magnetic resonance angiography, but digital subtraction angiography revealed severe stenosis of the left CCA and retrograde flow through the left ICA feeding the left ECA. Diverted blood flow from ECA to ICA in cases with occlusion or severe stenosis of the CCA represents a well-known alternative collateral flow pattern called ECA-to-ICA steal. However, collateral flow from ICA to ECA is rarely observed and may be termed ICA-to-ECA steal. We treated CCA stenosis in our patient by carotid artery stenting (CAS) because his CCA stenosis had been gradually progressing since the initial ischaemic attack. Antegrade ICA flow subsequently recovered. To the best of our knowledge, this is the first report of ICA-to-ECA steal normalised by the treatment of CCA stenosis using CAS.

Long-term treatment outcomes after intravascular ultrasound evaluation and stent placement for atherosclerotic subclavian artery obstructive lesions.

The objective of this study was to determine long-term outcomes after stent placement for subclavian artery (SA) obstructive lesions assisted by intraoperative intravascular ultrasound (IVUS). The study included 25 lesions in 24 patients who underwent stent placement assisted by intraoperative IVUS for subclavian artery stenosis or obstruction at our hospital between January 2003 and August 2010. Outcome was evaluated based on the results within 30 postoperative days (technical success rate, improvement in upper extremity ischemia, steal syndrome, left-right blood pressure difference, and perioperative complications) and the results after 30 postoperative days (incidence of vertebrobasilar artery territory infarction and restenosis). Stent placement and vessel dilatation were successful in all patients, without perioperative complications. Upper extremity ischemia, steal syndrome, and left-right blood pressure difference disappeared in all cases. During follow-up observation (6-96 months; median 51 months), no restenosis occurred at the stent placement site in any patient. In one case, four years after initial treatment, stenosis was noted proximal to the stent placement site. Satisfactory long-term as well as short-term outcomes were achieved after stent placement for SA obstructive lesions assisted by intraoperative IVUS evaluation.

Effect of pitavastatin on preventing ischemic complications with carotid artery stenting: a multicenter prospective study--EPOCH-CAS study.

PURPOSE: Periprocedural ischemic stroke is one problem associated with carotid artery stenting (CAS). This study was designed to assess whether preoperative statin therapy reduces the risk of periprocedural ischemic complications with CAS. METHODS: In this prospective study at 11 centers, patients with carotid artery stenosis (symptomatic ≥50%, asymptomatic ≥80%) and a high risk of carotid endarterectomy but without previous statin treatments were divided into two groups by low-density lipoprotein cholesterol (LDL-C) levels. With LDL-C ≥120 mg/dl, the pitavastatin-treated (PS) group received pitavastatin at 4 mg/day. With LDL-C <120 mg/dl, the non-PS group received no statin therapy. After 4 weeks, both groups underwent CAS. Frequencies of new ipsilateral ischemic lesions on diffusion-weighted imaging within 72 h after CAS and cerebrovascular events (transient ischemic attack, stroke, or death) within 30 days were assessed. RESULTS: Among the 80 patients enrolled, 61 patients (PS group, n = 31; non-PS group, n = 30) fulfilled the inclusion criteria. New ipsilateral ischemic lesions were identified in 8 of 31 patients (25.8%) in the PS group and 16 of 30 patients (53.3%) in the non-PS group (P = 0.028). Cerebrovascular events occurred in 0 patients in the PS group and in 3 of 30 patients (10.0%) in the non-PS group (P = 0.071). Multivariate analyses demonstrated the pitavastatin treatment (ß = 0.74, 95% confidence interval 0.070-1.48, P = 0.042) to be an independent factor for decreasing post-CAS ischemic lesions. CONCLUSION: Pretreatment with pitavastatin significantly reduced the frequency of periprocedural ischemic complications with CAS.

Carotid Wallstent placement difficulties encountered in carotid artery stenting.

PURPOSE: The present study aimed to identify the types of curved lesions that are difficult to place Carotid Wallstent (CWS). MATERIALS AND METHODS: The study targeted 31 consecutive carotid artery (CA) stenosis underwent carotid artery stenting using CWS. CWS placement success rate, stenosis location, lesion tortuosity, and relationship with stent placement failures were investigated. Lesion tortuosity was defined as the angle formed by 2 tangential lines between internal CA and common CA from the inflection point (IP) was defined as the center of lesion curvature. Stenosed lesions were classified into type A or B. Type A was defined as if the distal end of the stenosis was located proximal to the IP at a distance ≥0.5 of a vertebral body based on the posterior height of the 3rd vertebral body, otherwise was type B. RESULTS: The stent placement success rate was 93.5% (29/31). The 2 unsuccessfully stented lesions, both lesions were significantly different from other lesions by having a lesion tortuosity less than 90° and by belonging to type B. CONCLUSION: Since CWS placement is difficult in patients with CA stenosis located close to the IP at a lesion tortuosity ≤90°, open-cell stents should be considered as an alternative.

Usefulness of contrast-enhanced magnetic resonance angiography for follow-up of coil embolization with the enterprise stent for cerebral aneurysms.

OBJECTIVE: The aim of this study was to determine the feasibility and usefulness of contrast-enhanced magnetic resonance angiography (CE-MRA) and 3-dimensional (3D) time-of-flight (TOF) MRA for follow-up of intracranial aneurysms treated using the Enterprise stent. METHODS: Five aneurysm cases using the Enterprise stent were prospectively analyzed and were followed up with CE-MRA, 3D TOF MRA, and digital subtraction angiography (DSA). Depictions of parent artery lumen and the aneurysm neck with 3D TOF MRA and CE-MRA were compared with those of DSA. RESULTS: In all cases, on 3D TOF MRA, it was difficult to evaluate the parent artery lumen and aneurysm neck owing to the significant artifacts from the stent. Contrast-enhanced MRA sufficiently demonstrated parent artery lumen and aneurysm neck distinctly and as clear as DSA did in all cases. CONCLUSIONS: For follow-up after coiling with an Enterprise stent, CE-MRA may be necessary to avoid susceptibility artifacts caused by the stent.

Initial experience of carotid artery stenting using the Carotid WALLSTENT and FilterWire EZ in Japan.

PURPOSE: The Carotid WALLSTENT (CWS) and Filter-Wire EZ (FWEZ) embolic protection devices for use in carotid arterial stenting (CAS) were newly approved for national health insurance coverage in Japan in April 2010. This article describes our initial experience of CAS using the CWS and FWEZ. MATERIAL AND METHODS: A group of 14 patients (12 men, 2 women; mean age 70.1 years, range 59-83 years) with 15 carotid artery stenoses at high risk for carotid endarterectomy were treated by CAS using the CWS and FWEZ. Of these stenoses, 5 were symptomatic with ≥50% stenosis of the common or internal carotid artery (ICA), and 10 were asymptomatic with ≥80% stenosis. The rates of technical success, ICA flow impairment during filter protection, periprocedural ischemic stroke, 30-day major adverse events (MAEs) (stroke, death, myocardial infarction), and development of new ischemic lesions on diffusion-weighted imaging (DWI) were assessed. RESULTS: CAS was successful in all cases. There was no ICA flow impairment, periprocedural ischemic stroke, or MAEs. DWI showed new ipsilateral ischemic lesions in only one patient (6.7%). CONCLUSION: Our initial clinical experience using the CWS and FEWZ for CAS was generally excellent, and the incidence of postprocedural ischemic lesions was low.

Magnetic resonance plaque imaging to predict the occurrence of the slow-flow phenomenon in carotid artery stenting procedures.

INTRODUCTION: The purpose is to investigate the feasibility of magnetic resonance (MR) plaque imaging in predicting the arterial flow impairment (slow-flow phenomenon) during carotid artery stenting (CAS) using a filter-type protection device. METHODS: Thirty-one carotid artery stenotic lesions in 30 patients (28 men and two women; mean age, 71.8 years) were evaluated by MR plaque imaging with black blood T1- and T2-weighted and time-of-flight sequences before CAS. Main plaque components were classified as vulnerable (intraplaque hemorrhage and lipid-rich/necrotic core) or stable (fibrous tissue and dense calcification) from the signal pattern. The plaque classification was statistically compared with the occurrence of slow-flow phenomenon. RESULTS: The slow-flow phenomenon was observed in ten CAS procedures (five flow arrests and five flow reductions). Flow arrests consisted of four vulnerable and one stable plaque, and flow reductions consisted of four vulnerable and one stable plaque. The slow-flow phenomenon occurred significantly (P<0.01) more frequently in patients with vulnerable plaque. CONCLUSIONS: Vulnerable carotid plaques have a significantly higher risk of slow-flow phenomenon than stable plaques. The occurrence of the slow-flow phenomenon can be predicted by MR plaque imaging before CAS.