What Is the Best Technique for Treating Carotid Disease?

This is a comprehensive review of carotid artery revascularization techniques: Carotid Endarterectomy (CEA), Transfemoral Carotid Artery Stenting (TFCAS), and Transcarotid Artery Revascularization (TCAR). CEA is the gold standard and is particularly effective in elderly and high-risk patients. TFCAS, introduced as a less invasive alternative, poses increased periprocedural stroke risks. TCAR, which combines minimally invasive benefits with CEA's neuroprotection principles, emerges as a safer option for high-risk patients, showing comparable results to CEA and better outcomes than TFCAS. The decision-making process for carotid revascularization is complex and influenced by the patient's medical comorbidities and anatomic factors.

Aphasia due to right hemisphere infarction in a patient with situs inversus after carotid artery stenting: a case report.

BACKGROUND: Situs inversus (SI) is a rare congenital anomaly in which systemic organs and vessels are positioned in a mirror image of their normal positions. An interesting issue regarding individuals with such a condition is whether they also have reversed brain asymmetries. Most of studies on this issue indicate that, similarly to many people with normal visceral alignment, patients with SI have a left hemispheric dominance for language functions. CASE PRESENTATION: We report a rare occurrence of anomalous cerebral dominance for language in a patient with complete situs inversus. The right-handed patient developed aphasia after carotid stenting, and brain magnetic resonance imaging showed cerebral infarction in the right parietal lobe. CONCLUSION: Anomalous cerebral dominance for language and visceral situs inversus in our patient both may result from a single, genetically coded atypicality of developmental gradient.

Influence of Carotid Artery Stenting on the Retina and Choroid.

Purpose: The effect of carotid artery stenting in patients with unilateral carotid artery stenosis on the retina and choroid was evaluated using swept-source optical coherence tomography angiography (SS-OCTA). Methods: SS-OCTA examination was conducted before stenting and 4 days and 3 months after stenting. The retinal nerve fiber layer, ganglion cell-inner plexiform layer (GCIPL), inner nuclear layer, superficial vascular complex (SVC), deep vascular complex (DVC), choroidal vascular volume (CVV), and choroidal vascular index were measured. Repeated-measures analysis of variance was performed to assess the impact of carotid artery stenting on optical coherence tomography angiography (OCTA) metrics. Results: At baseline, 303 eyes from 160 patients (61.82 ± 9.98 years; 85.29% males) were enrolled. SVC and DVC densities and CVV were lower in ipsilateral eyes (stenosed side) compared to contralateral eyes (all P < 0.05). Four days after stenting, a significant increase was seen in SVC density in ipsilateral eyes (P < 0.05) while a significant increase was seen in CVV in ipsilateral eyes and contralateral eyes (both P < 0.05). Three months after stenting (63 patients with 114 eyes), a significant decrease was seen in the GCIPL thickness of ipsilateral and contralateral eyes (all P < 0.001). Conclusions: Short term after carotid artery stenting, ipsilateral eyes showed a rapid and significant increase in SVC density and CVV. Translational Relevance: Optical coherence tomography (OCT)/OCTA measurements may have the potential to detect retinal and choroidal changes after stenting. Future research on the long-term effect of stenting on the retina and choroid will be guided by these findings.

Comparison of optical coherence tomography angiography results in patients with internal carotid artery stenosis who underwent carotid artery stenting and carotid endarterectomy.

It is important to examine the ocular hemodynamic changes after carotid artery stenting (CAS) and carotid endarterectomy (CEA) in patients with internal carotid artery stenosis (ICAS). We aimed to compare the differences in retinal and optic nerve head blood flow after 2 surgical methods. The ipsilateral eyes of 34 patients who had over 50% ICAS with no ocular findings and 30 healthy controls were included in the study. Foveal avascular zone vessel density in the superficial retinal capillary plexus, deep retinal capillary plexus (DCP), and radial peripapillary capillary plexus (RPCP) were measured with an optical coherence tomography angiography device. These measurements were repeated 1 month after CAS or CEA in patients with ICAS. The preoperative and postoperative values of the patients were compared both within themselves and with the control group. When patients with ICAS were compared with the control group, lower vessel density values were found in the DCP parafovea, RPCP whole image, and peripapillary regions both before and after the procedure. There was no significant difference in terms of other parameters. Furthermore, there was no significant difference in any parameter examined between the pre- and postprocedural values of the patients who underwent CAS and CEA. DCP and RPCP are mostly affected in patients with ICAS. We observed that after application of the CAS and CEA methods, the effects on ocular blood flow were similar.

[Treatment of tandem occlusions of the common and internal carotid arteries]. / Behandlung von Tandemstenosen der A. carotis communis und A. carotis interna.

BACKGROUND: Proximal carotid tandem lesions are defined as multilevel lesions with significant (> 50%) atherosclerotic disease involving the internal carotid artery (ICA) in combination with the proximal ipsilateral common carotid artery (CCA) or innominate artery (IA). It is a relatively rare disease with an incidence of less than 5% in all patients with carotid stenosis at the level of the bifurcation. METHODS: These patients are at high surgical risk and were, therefore, excluded from current randomized controlled trials. Although the effectiveness of carotid endarterectomy (CEA) and carotid stenting (CAS) in stroke prevention for patients is established, the optimal treatment approach for the subgroup of patients with a proximal tandem lesion is still controversial. Treatment of this condition is not well understood because it is difficult to determine the risk of each individual lesion becoming symptomatic. Therefore, concurrent treatment of severe (> 70% stenosis) proximal lesions is recommended when treating severe stenosis at the carotid bifurcation. CONCLUSION: This disease can lead to embolic ischemic strokes or hemodynamic compromise. It is not possible to determine diagnostically which lesion led to the clinical symptoms, which is why both lesions should be corrected.

Hybrid Surgery for symptomatic chronic internal carotid artery occlusion: a single-center experience.

BACKGROUND: Patients with symptomatic chronic internal carotid artery occlusion (ICAO) face a high risk of recurrent stroke despite receiving aggressive medical therapy. This study aimed to evaluate the effectiveness and safety of hybrid surgery in treating symptomatic chronic ICAO. METHODS: This retrospective case series was conducted at a single center. From January 2019 to December 2022, patients with symptomatic chronic ICAO who underwent hybrid surgery were included. We collected baseline data, lesion characteristics, revascularization rates, perioperative complications, and follow-up outcomes. RESULTS: The study enrolled 27 patients, comprising 22 males and 5 females, with symptomatic chronic ICAO. The hybrid surgery achieved a technical success rate of 100% for revascularization (n = 27), with a perioperative complication rate of 14.8% (n = 4). Following a median follow-up of 6.0 months (IQR, 4-10), 21 patients underwent a DSA or CT angiography reexamination, confirming a vascular patency rate of 90.5% (n = 19). One patient required surgery for severe in-stent restenosis, and another experienced asymptomatic occlusion. Clinical follow-ups were conducted for all 26 patients; no new strokes were reported in the qualifying artery territory, with 13 patients scoring 0, 12 scoring 1, and 1 scoring 2 on the mRS. CONCLUSION: Although hybrid surgery represent a promising option for treating chronic ICAO, they are also associated with a relatively high incidence of treatment-related complications. The application of composite surgery should be based on standardized technical guidelines and the careful selection of patients who are genuinely at high risk for recurrent strokes.

How i do it: individualized bypass strategy with tentative clamping method.

BACKGROUND: Cerebral Revascularization (CR) remained an indispensable arm in the neurosurgical arsenal, especially managing symptomatic hemisphere with misery perfusion (SHMP). METHOD: We described an a mid-aged gentleman diagnosed with progressive middle cerebral steno-occlusion following carotid endarterectomy by employing individualized arterial reconstruction with tentative clamping method (TCM) under supervision of intraoperative monitoring. An operative video was also accompanied to demonstrate further details. CONCLUSION: The optimal treatment strategy for SHMP should be tailored by individuals. The risk of postoperative adverse sequel can be minimized and improved neuro-cognitive status was accomplished with an aid of TCM for such prophylactic procedure. CLINICAL TRIAL REGISTRATION: NA.

Using Machine Learning to Predict Outcomes Following Transfemoral Carotid Artery Stenting.

BACKGROUND: Transfemoral carotid artery stenting (TFCAS) carries important perioperative risks. Outcome prediction tools may help guide clinical decision-making but remain limited. We developed machine learning algorithms that predict 1-year stroke or death following TFCAS. METHODS AND RESULTS: The VQI (Vascular Quality Initiative) database was used to identify patients who underwent TFCAS for carotid artery stenosis between 2005 and 2024. We identified 112 features from the index hospitalization (82 preoperative [demographic/clinical], 13 intraoperative [procedural], and 17 postoperative [in-hospital course/complications]). The primary outcome was 1-year postprocedural stroke or death. The data were divided into training (70%) and test (30%) sets. Six machine learning models were trained using preoperative features with 10-fold cross-validation. The primary model evaluation metric was area under the receiver operating characteristic curve. The algorithm with the best performance was further trained using intra- and postoperative features. Model robustness was assessed using calibration plots and Brier scores. Overall, 35 214 patients underwent TFCAS during the study period and 3257 (9.2%) developed 1-year stroke or death. The best preoperative prediction model was extreme gradient boosting, achieving an area under the receiver operating characteristic curve of 0.94 (95% CI, 0.93-0.95). In comparison, logistic regression had an AUROC of 0.65 (95% CI, 0.63-0.67). The extreme gradient boosting model maintained excellent performance at the intra- and postoperative stages, with area under the receiver operating characteristic curve values of 0.94 (95% CI, 0.93-0.95) and 0.98 (95% CI, 0.97-0.99), respectively. Calibration plots showed good agreement between predicted/observed event probabilities with Brier scores of 0.11 (preoperative), 0.11 (intraoperative), and 0.09 (postoperative). CONCLUSIONS: Machine learning can accurately predict 1-year stroke or death following TFCAS, performing better than logistic regression.

Outcomes in acute carotid-related stroke eligible for mechanical reperfusion: SAFEGUARD-STROKE Registry.

BACKGROUND: Carotid-related strokes (CRS) are largely unresponsive to intravenous thrombolysis and are often large and disabling. Little is known about contemporary CRS referral pathways and proportion of eligible patients who receive emergency mechanical reperfusion (EMR). METHODS: Referral pathways, serial imaging, treatment data, and neurologic outcomes were evaluated in consecutive CRS patients presenting over 18 months in catchment area of a major carotid disease referral center with proximal-protected CAS expertise, on-site neurology, and stroke thrombectomy capability (Acute Stroke of CArotid Artery Bifurcation Origin Treated With Use oF the MicronEt-covered CGUARD Stent - SAFEGUARD-STROKE Registry; companion to SAFEGUARD-STROKE Study NCT05195658). RESULTS: Of 101 EMR-eligible patients (31% i.v.-thrombolyzed, 39.5% women, age 39-89 years, 94.1% ASPECTS 9-10, 90.1% pre-stroke mRS 0-1), 57 (56.4%) were EMR-referred. Referrals were either endovascular (Comprehensive Stroke Centre, CSC, 21.0%; Stroke Thrombectomy-Capable CAS Centre, STCC, 70.2%) or to vascular surgery (VS, 1.8%), with >1 referral attempt in 7.0% patients (CSC/VS or VS/CSC or CSC/VS/STCC). Baseline clinical and imaging characteristics were not different between EMR-treated and EMR-untreated patients. EMR was delivered to 42.6% eligible patients (emergency carotid surgery 0%; STCC rejections 0%). On multivariable analysis, non-tandem CRS was a predictor of not getting referred for EMR (OR 0.36; 95%CI 0.14-0.93, P=0.03). Ninety-day neurologic status was profoundly better in EMR-treated patients; mRS 0-2 (83.7% vs. 34.5%); mRS 3-5 (11.6% vs. 53.4%), mRS 6 (4.6% vs. 12.1%); P<0.001 for all. CONCLUSIONS: EMR-treatment substantially improves CRS neurologic outcomes but only a minority of EMR-eligible patients receive EMR. To increase the likelihood of brain-saving treatment, EMR-eligible stroke referral and management pathways, including those for CSC/VS-rejected patients, should involve stroke thrombectomy-capable centres with endovascular carotid treatment expertise.

Next-generation transcarotid artery revascularization: TransCarotid flOw Reversal Cerebral Protection And CGUARD MicroNET-Covered Embolic Prevention Stent System To Reduce Strokes - TOPGUARD Study.

BACKGROUND: Stent-assisted carotid artery revascularization employing surgical cutdown for transcervical access and dynamic flow reversal (TCAR) is gaining popularity. TCAR, despite maximized intra-procedural cerebral protection, shows a marked excess of 30-day neurologic complications in symptomatic vs. asymptomatic stenoses. The TCAR conventional single-layer stent (free-cell area 5.89mm2) inability to seal embologenic lesions may be particularly relevant after the flow reversal neuroprotection is terminated. METHODS: We evaluated peri-procedural and 30-day major adverse cerebral and cardiac events (MACCE) of TCAR (ENROUTE, SilkRoad Medical) paired with MicroNET-covered neuroprotective stent (CGuard, InspireMD) in consecutive patients at elevated risk of complications with transfemoral/transradial filter-protected stenting (increased lesion-related and/or access-related risk). CGuard (MicroNET free cell area ≈0.02-0.03 mm2) has level-1 evidence for reducing intra- and abolishing post-procedural lesion-related cerebral embolism. RESULTS: One hundred and six increased-risk patients (age 72 [61-76] years, median [Q1-Q3]; 60.4% symptomatic, 49.1% diabetic, 36.8% women, 61.3% left-sided index lesion) were enrolled in three vascular surgery centers. Angiographic stenosis severity was 81 (75-91)%, lesion length 21 (15-26)mm, increased-risk lesional characteristics 87.7%. Study stent use was 100% (no other stent types). 74.5% lesions were predilated; post-dilatation rate was 90.6%. Flow reversal duration was 8 (5-11)min. One stroke (0.9%) occurred in an asymptomatic patient prior to establishing neuroprotection (index lesion disruption with the sheath insertion wire); there were no other peri-procedural MACCE. No further adverse events occurred by 30-days. 30-day stent patency was 100% with normal velocities and absence of any in-stent material by Duplex Doppler. CONCLUSIONS: Despite a high proportion of increased-risk lesions and clinically symptomatic patients in this study, TCAR employing the MicroNET-covered anti-embolic stent showed 30-day MACCE rate <1%. This suggests a clinical role for combining maximized intra-procedural prevention of cerebral embolism by dynamic flow reversal with anti-embolic stent prevention of peri- and post-procedural cerebral embolism (TOPGUARD NCT04547387).

Carotid artery stenting with flow inversion cerebral protection and MicroNet-covered stent.

BACKGROUND: The study aims to evaluate the association of proximal flow-inversion cerebral protection and MicroNet-covered CGuard stents in reducing early and late embolic events in carotid artery stenting procedures. METHODS: From 2018 to 2023, we performed 204 procedures in 180 patients with flow inversion cerebral protection and CGuard stents at the Vascular Surgery Unit of Sant'Eugenio Hospital in Rome. Cerebral protection was achieved with a Flow-Gate2 catheter connected to a peripheral vein. The tip balloon is inflated in the CCA to obtain an effective endoclamping, the pressure difference between the carotid bifurcation and the venous compartment ensures a constant back flow with wash-out in the venous compartment. Inclusion criteria were: life expectancy of >12 months, target lesions indicating treatment according to ESVS Guidelines, increased surgical risk due to comorbidities or anatomic issues. ECD follow-up was performed immediately postoperatively, at 30 days, 6 and 12 months, and subsequently annually. RESULTS: The treatment protocol was successfully implemented in 99% of cases. No major strokes occurred, while one minor stroke (0.5%) occurred within 8 hours of the procedure, regressing in the following months. One perioperative death (0.5%) due to cerebral hemorrhage occurred three hours after the procedure. All patients remained asymptomatic, with no short or medium-term neurological score deterioration. One hemodynamically significant restenosis (0.5%) was detected at the 6-month follow-up. All patients completed the 6 months follow-up, though 6 (3%) were lost at the 12-month appointment. CONCLUSIONS: Our prospective monocentric study has demonstrated the effectiveness and safety of the FlowGate2 flow inversion cerebral protection system in association with MicroNet covered CGuard stent.

Comparative analysis of carotid artery stenting practice and outcomes across operator specialties: insights from a prespecified subanalysis of a large real-world patient cohort (ROADSAVER Study).

BACKGROUND: In contemporary clinical practice, carotid artery stenting (CAS) is increasingly becoming a multispecialty field, joining operators of various training backgrounds, which bring forth their unique expertise, patient management philosophies, and procedural preferences. The best practices and approaches, however, are still debated. Therefore, real-world insights on different operator preferences and related outcomes are of utmost value, yet still rather scarce in the available literature. METHODS: Using the data collected in the ROADSAVER observational, European multicenter CAS study, a prespecified comparative analysis evaluating the impact of the operator's specialization was performed. We used major adverse event (MAE) rate at 30-day follow-up, defined as the cumulative incidence of any death or stroke, and its components as outcome measures. RESULTS: A total of 1965 procedures were analyzed; almost half 878 (44.7%) were performed by radiologists (interventional/neuro), 717 (36.5%) by cardiologists or angiologists, and 370 (18.8%) by surgeons (vascular/neuro). Patients treated by surgeons were the oldest (72.9±8.5), while radiologists treated most symptomatic patients (58.1%) and more often used radial access (37.2%). The 30-day MAE incidence achieved by cardiologists/angiologists was 2.0%, radiologists 2.5%, and surgeons 1.9%; the observed differences in rates were statistically not-significant (P=0.7027), even when adjusted for baseline patient/lesion and procedural disparities across groups. The corresponding incidence rates for death from any cause were 1.0%, 0.8%, and 0.3%, P=0.4880, and for any stroke: 1.4%, 2.3%, and 1.9%, P=0.4477, respectively. CONCLUSIONS: Despite the disparities in patient selection and procedural preferences, the outcomes achieved by different specialties in real-world, contemporary CAS practice remain similar when using modern devices and techniques.

Navigating complexity with low-crossing profile dual-layer micromesh carotid stent: implications for contemporary carotid artery stenting outcomes (ROADSAVER study insights).

BACKGROUND: The safety and efficacy of carotid artery stenting (CAS) can be affected by certain technical and anatomical factors. However, it is not known whether the use of a dual-layer micromesh stent (DLMS) with a low-crossing profile could reduce the risks associated with complex vascular anatomies during CAS. METHODS: This study involved 1965 asymptomatic or symptomatic carotid artery stenosis patients who received the Roadsaver DLMS during CAS, as part of a prospective, multicenter observational ROADSAVER study, conducted from January 2018 to February 2021. The primary outcome was the 30-day rate of major adverse events (MAE; i.e. any death or stroke) after CAS. Procedural details and outcomes were compared between patients with complex anatomical features and those without. RESULTS: One or more complex anatomical characteristics were identified in 1639 (83.4%) patents. Patients with complex anatomies were older and had a higher prevalence of arterial hypertension, cardiovascular disease, and prior stroke. Between patients with or without complex anatomical features, no significant differences were found either in procedural techniques, or in 30-day MAE (age-adjusted odds ratio (95% CI) for complexities vs. no complexities: 0.76 (0.35, 1.66); p=0.4905) and any stroke (age-adjusted odds ratio (95% CI) for complexities vs. no complexities: 0.89 (0.37, 2.17); p=0.8032) incidence. Furthermore, neither the presence of specific types of anatomic complexity nor their number (per patient) markedly influenced the 30-day MAE and any stroke incidence. CONCLUSIONS: In this real-world cohort of patients undergoing CAS with the Roadsaver DLMS, no significant difference in the occurrence of 30-day MAE and any stroke was observed between patients with or without high-risk anatomical features.

Mediation Analysis of Acute Carotid Stenting in Tandem Lesions: Effect on Functional Outcome in a Multicenter Registry.

BACKGROUND AND OBJECTIVES: Current evidence suggests that acute carotid artery stenting (CAS) for cervical lesions is associated with better functional outcomes in patients with acute stroke with tandem lesions (TLs) treated with endovascular therapy (EVT). However, the underlying causal pathophysiologic mechanism of this relationship compared with a non-CAS strategy remains unclear. We aimed to determine whether, and to what degree, reperfusion mediates the relationship between acute CAS and functional outcome in patients with TLs. METHODS: This subanalysis stems from a multicenter retrospective cohort study across 16 stroke centers from January 2015 to December 2020. Patients with anterior circulation TLs who underwent EVT were included. Successful reperfusion was defined as a modified Thrombolysis in Cerebral Infarction scale ≥2B by the local team at each participating center. Mediation analysis was conducted to examine the potential causal pathway in which the relationship between acute CAS and functional outcome (90-day modified Rankin Scale) is mediated by successful reperfusion. RESULTS: A total of 570 patients were included, with a median age (interquartile range) of 68 (59-76), among whom 180 (31.6%) were female. Among these patients, 354 (62.1%) underwent acute CAS and 244 (47.4%) had a favorable functional outcome. The remaining 216 (37.9%) patients were in the non-CAS group. The CAS group had significantly higher rates of successful reperfusion (91.2% vs 85.1%; p = 0.025) and favorable functional outcomes (52% vs 29%; p = 0.003) compared with the non-CAS group. Successful reperfusion was a strong predictor of functional outcome (adjusted common odds ratio [acOR] 4.88; 95% CI 2.91-8.17; p < 0.001). Successful reperfusion partially mediated the relationship between acute CAS and functional outcome, as acute CAS remained significantly associated with functional outcome after adjustment for successful reperfusion (acOR 1.89; 95% CI 1.27-2.83; p = 0.002). Successful reperfusion explained 25% (95% CI 3%-67%) of the relationship between acute CAS and functional outcome. DISCUSSION: In patients with TL undergoing EVT, successful reperfusion predicted favorable functional outcomes when CAS was performed compared with non-CAS. A considerable proportion (25%) of the treatment effect of acute CAS on functional outcome was found to be mediated by improvement of successful reperfusion rates.

A meta-analysis supporting the superiority of staged carotid artery stenting and coronary artery bypass grafting in patients with concurrent severe coronary and carotid artery stenosis.

BACKGROUND: This study sought to ascertain whether a staged approach involving carotid artery stenting (CAS) and coronary artery bypass grafting (CABG) holds superiority over the synchronous (Syn) strategy of CAS or carotid endarterectomy (CEA) and CABG in patients necessitating combined revascularization for concurrent carotid and coronary artery disease. METHOD: Studies were identified through 3 databases: PubMed, EMBASE, and the Cochrane Library. Statistical significance was defined as a P value of less than .05 for all analyses, conducted using STATA version 12.0. RESULTS: In the comparison between staged versus Syn CAS and CABG for patients with concomitant severe coronary and carotid stenosis, 4 studies were analyzed. The staged procedure was associated with a lower rate of 30-day stroke (OR = 8.329, 95% CI = 1.017-69.229, P = .048) compared to Syn CAS and CABG. In the comparison between staged CAS and CABG versus Syn CEA and CABG for patients with concomitant severe coronary and carotid stenosis, 5 studies were examined. The staged CAS and CABG procedure was associated with a lower rate of mortality (OR = 2.046, 95% CI = 1.304-3.210, P = .002) compared to Syn CEA and CABG. CONCLUSION: The Syn CAS and CABG was linked to a higher risk of peri-operative stroke compared to staged CAS and CABG. Additionally, patients undergoing staged CAS and CABG exhibited a significantly decreased risk of 30-day mortality compared to Syn CEA and CABG. Future randomized trials or prospective cohorts are essential to confirm and validate these findings.

Predicting impaired cerebrovascular reactivity and risk of hyperperfusion syndrome in carotid artery stenosis using BeamSAT magnetic resonance imaging.

Pencil-beam presaturation (BeamSAT) magnetic resonance imaging (MRI) produces selective magnetic resonance angiography (MRA) images of specific arteries, including the unilateral internal carotid artery (ICA-selective MRA) or vertebral artery (VA-selective MRA). We evaluate the influence of flow pattern, visualized using BeamSAT MRI, on preoperative cerebral hemodynamic status and postoperative hyperperfusion syndrome (HPS). Patients undergoing carotid artery stenting or carotid endarterectomy were categorized into two groups to evaluate flow pattern. Patients with neither crossflow on BeamSAT MRI nor mismatch in middle cerebral artery (MCA) signal intensity between ICA-selective and conventional MRA were classified into Group I, comprising 29 patients. Group II included all other patients comprising 19 patients, who were suspected of experiencing changes in intracranial flow patterns. Cerebral blood flow and cerebrovascular reactivity (CVR) were assessed using single-photon emission computed tomography, and potential HPS symptoms were retrospectively assessed by chart review. Preoperative ipsilateral CVR was significantly lower in Group II than in Group I (18.0% ± 20.0% vs. 48.3% ± 19.5%; P < 0.0001). Group II showed significantly impaired CVR (odds ratio 17.7, 95% confidence interval 1.82-171; P = 0.013) in multivariate analysis. The partial areas under the curve of the BeamSAT logistic model (0.843) were significantly larger than those of the conventional logistic model (0.626) over the range of high sensitivity (0.6-1) (P = 0.04). The incidence of postoperative HPS symptoms was significantly higher in Group II than in Group I (8/19 vs. 1/29; P = 0.001). BeamSAT MRI may be a valuable and non-invasive tool for assessing cerebral hemodynamics and predicting postoperative HPS.

Outcome of CAS under flow reversal and analysis for the intraprocedural flow of internal carotid artery.

OBJECTIVE: Carotid artery stenting (CAS) under flow reversal with dual protection using a proximal balloon and distal filter has been an established procedure for internal carotid artery (ICA) stenosis. This study investigates the effect of external carotid artery (ECA) occlusion on outcomes of CAS and ICA flow under flow reversal. METHODS: We reviewed 231 cases of CAS under flow reversal with ECA occlusion and 32 without. In the last 14 of 32 cases, the flow in the ICA under flow reversal was analyzed by ultrasound. The collateral index, which was defined as the total value of the maximum diameters of the ipsilateral anterior cerebral artery at the A1 segment and the anterior communicating artery, as well as those of the ipsilateral posterior cerebral artery at the P1 segment and the ipsilateral posterior communicating artery, and the maximum diameter of the ipsilateral ECA were correlated with the flow direction in the ICA. RESULTS: There was no significant difference in the outcome of CAS between the groups with or without ECA occlusion. Among the 14 cases without ECA occlusion, antegrade flow in the ICA was observed in 6 cases (42.9 %). The group with the antegrade flow in the ICA exhibited a significantly lower collateral index (5.08±0.33 vs 6.71±0.28, p=0.01) and a significantly larger ECA diameter (4.66±0.51 mm vs 3.21±1.24 mm, p=0.01) than the group with the stagnant or retrograde flow in the ICA. CONCLUSIONS: The outcomes of CAS under flow reversal were acceptable even without ECA occlusion. The ECA occlusion may not be necessary for CAS under dual protection; however, distal filter protection should be used even under flow reversal.