Symptomatic Middle Cerebral Artery Stenosis Research Articles

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.

Abstract WP142: Investigating the Association of Intracranial Stenosis With Low Wall Shear Stress

Background: Intracranial atherosclerotic disease (ICAD) is associated with high recurrence rates of stroke despite aggressive medical management. Low wall shear stress (WSS) alters endothelial function and changes in WSS within the post-stenotic region of ICAD lesions is a potential driver of stroke recurrence. Methods: Using the SAMMPRIS imaging dataset, we identified medically managed patients with symptomatic middle cerebral artery (MCA) stenosis measured by CTA. WSS was calculated by creating a 3D volumetric mesh from CTA source imaging. Pulsatile flow profile reference standard boundary conditions were applied at pressure outlets to simulate normal hemodynamics. Arterial segments extending from the stenosis to the MCA bifurcation were captured and quantified. Contralateral arterial segments were matched by length and area. The ratio of area with low WSS (<4 dyne/cm 2 ) on both sides was then calculated. Differences in the mean arterial area with low WSS and ratio of area with low WSS were compared using paired Student’s t-test with data presented as mean ± SD. Results: Of 451 cases in SAMMPRIS, the medical management arm had 105 MCA cases of which 47 cases had CTA available and 33 cases were able to be analyzed by computational flow dynamics. Symptomatic ICAD lesions demonstrated significant differences in post stenosis area with low WSS (24.7±43.4 mm 2 vs 2.8±3.4 mm 2 p=0.003) and differences in the low WSS ratio (0.25±0.26 vs0.04±0.05 p<0.001). There was no statistically significant difference in the length and area of the arterial segment post stenosis to the bifurcation and the control length on the contralateral side (11.6±7.4 mm vs 10.6±6.1 mm p=0.566; 80.7±55.0 mm 2 vs 95.4±58.3 mm 2 p=0.298). Conclusion: Area with low WSS after ICAD stenoses is increased in the SAMMPRIS imaging dataset and may be a marker of symptomatic ICAD. Further studies are needed to evaluate the association of post stenotic WSS with symptomatic recurrent stroke.

Drug-Coated Balloon-Oriented Angioplasty for Severe Symptomatic Atherosclerotic MCA Stenosis in Young Adults.

PurposeThe clinical significance of endovascular therapy in young patients with symptomatic intracranial atherosclerotic stenosis is not clear. We aimed to report our preliminary findings on the safety and effectiveness of a new endovascular treatment strategy, drug-coated balloon (DCB)-oriented angioplasty for young adults with severe symptomatic atherosclerotic middle cerebral artery (MCA) stenosis.MethodsWe retrospectively retrieved the data of seven young patients aged 21–32 years old with severe symptomatic atherosclerotic MCA stenosis treated with DCB-oriented angioplasty from January 2018 to October 2020. We collected clinical presentations, perioperative complications, and clinical and radiological outcomes.ResultsThe DCB was successfully dilated at the lesions in all seven patients and good antegrade perfusion was achieved in five. The other two patients underwent remedial stent implantation due to residual stenosis >50% and unstable antegrade perfusion after DCB dilatation. However, none of the patients had perioperative complications. There were no recurrent ischemic symptoms after a mean clinical follow-up period of 15.4 ± 6.9 months. Repeat vascular images of the patients showed no restenosis at 3- or 6-month imaging follow-up periods. High-resolution MRI (HRMRI) was completed in all the patients before the angioplasty procedure and at follow-up. Focal eccentric wall thickening was present at the site of stenosis preoperatively; however, the plaques had disappeared by the time of follow-up for all patients.ConclusionDCB-oriented angioplasty may be safe and effective for young patients with severe symptomatic atherosclerotic MCA stenosis.

Hemodynamic Versus Anatomic Assessment of Symptomatic Atherosclerotic Middle Cerebral Artery Stenosis: the Relationship Between Pressure Wire Translesional Gradient and Angiographic Lesion Geometry.

Background: Intracranial cerebral atherosclerosis (ICAS) is a leading etiology of ischemic stroke. The diagnosis and assessment of intracranial stenosis are shifting from anatomic to hemodynamic for better risk stratification. However, the relationships between lesion geometry and translesional pressure gradient have not been clearly elucidated.Methods: Patients with symptomatic unifocal M1 middle cerebral artery (M1-MCA) stenosis were consecutively recruited. The translesional pressure gradient was measured with a pressure wire and was recorded as both mean distal/proximal pressure ratios (Pd/Pa) and translesional pressure difference (Pa–Pd). Lesion geometry measured on angiography was recorded as diameter stenosis, minimal lumen diameter, and lesion length. The correlations between pressure-derived and angiography-derived indices were then analyzed.Results: Forty-three patients were analyzed. A negative correlation was found between Pd/Pa and diameter stenosis (r = −0.371; p = 0.014) and between Pa – Pd and minimal lumen diameter (r = −0.507; p = 0.001). A positive correlation was found between Pd/Pa and minimal lumen diameter (r = 0.411; p = 0.006) and between Pa – Pd and diameter stenosis (r = 0.466; p = 0.002).Conclusions: In a highly selected ICAS subgroup, geometric indices derived from angiography correlate significantly with translesional pressure gradient indices. However, the correlation strength is weak-to-moderate, which implies that anatomic assessment could only partly reflect hemodynamic status. Translesional pressure gradient measured by pressure wire may serve as a more predictive marker of ICAS severity. More factors need to be identified in further studies.

A Comparison of Safety and Effectiveness Between Wingspan and Neuroform Stents in Patients With Middle Cerebral Artery Stenosis.

Background: Percutaneous transluminal angioplasty and stenting with the Wingspan stent has proven safe and effective in patients with middle cerebral artery stenosis (MCAS), but the off-label use of the Neuroform stent might be an alternative treatment. This study aimed to compare the safety and effectiveness of the above two intracranial stents in patients with MCAS.Methods: We retrospectively analyzed consecutive patients with symptomatic MCAS who had been treated with the Neuroform EZ or the Wingspan stent. A propensity score was generated to control for differences in baseline characteristics. The endpoints were the rate of peri-procedural complications within 30 days after stenting, the in-stent restenosis rate, and any target-vessel-related stroke or deaths during follow-up.Results: After matching for propensity score, the peri-procedural complication rate in the Wingspan group was 7.4% compared with 5.6% in the Neuroform group (p = 1.00), while the follow-up in-stent restenosis rates were 23.3 vs. 14.3%, respectively (p = 0.41). In the restenosis group, the patients tended to be younger (p < 0.01) and the degree of artery stenosis before stenting was higher (p < 0.01).Conclusion: This study indicated that in patients with symptomatic MCAS, Neuroform EZ stents are an alternative to Wingspan. Moreover, younger age and higher degree of artery stenosis before stenting might be a risk factor of in-stent restenosis.

Evaluating the Velocity and Extent of Cortical Venous Filling in Patients With Severe Middle Cerebral Artery Stenosis or Occlusion.

Objective: To investigate the velocity and extent of cortical venous filling (CVF) and its association with clinical manifestations in patients with severe stenosis or occlusion of the middle cerebral artery (MCA) using dynamic computed tomography angiography (CTA).Methods: Fifty-eight patients (36 symptomatic and 22 asymptomatic) with severe unilateral stenosis (≥70%) or occlusion of the MCA M1 segment who underwent dynamic CTA were included. Collateral status, antegrade flow, and CVF of each patient were observed using dynamic CTA. Three types of cortical veins were selected to observe the extent of CVF, and the absence of CVF (CVF-) was recorded. Based on the appearance of CVF in the superior sagittal sinus, instances of CVF, including early (CVF1), peak (CVF2), and late (CVF3) venous phases, were recorded. The differences in CVF times between the affected and contralateral hemispheres were represented as rCVFs, and CVF velocity was defined compared to the median time of each rCVF.Results: All CVF times in the affected hemisphere were longer than those in the contralateral hemisphere (p < 0.05). Patients with symptomatic MCA stenosis had more ipsilateral CVF- (p = 0.02) and more delayed CVF at rCVF2 and rCVF21 (rCVF2-rCVF1) (p = 0.03 and 0.001, respectively) compared to those with asymptomatic MCA stenosis. For symptomatic patients, fast CVF at rCVF21 was associated with poor collateral status (odds ratio [OR] 6.42, 95% confidence interval [CI] 1.37–30.05, p = 0.02), and ipsilateral CVF- in two cortical veins was associated with poor 3-month outcomes (adjusted OR 0.025, 95% CI 0.002–0.33, p = 0.005).Conclusions: Complete and fast CVF is essential for patients with symptomatic MCA stenosis or occlusion. The clinical value of additional CVF assessment should be explored in future studies to identify patients with severe MCA stenosis or occlusion at a higher risk of stroke occurrence and poor recovery.

Abstract P575: Impaired Distal Perfusion Predicts In-Hospital Outcome in Patients With Symptomatic Middle Cerebral Artery Stenosis

Background: Perfusion imaging is increasingly used to risk stratify patients with symptomatic intracranial stenosis. Length of hospital stay (LOS) in patients with ischemic stroke is a surrogate marker of increased morbidity. We aim to determine the association between perfusion delay on T max (&lt; 4 sec, 4-6 sec, and &gt; 6 sec) on perfusion weighted imaging and LOS in patients with symptomatic middle cerebral artery (MCA) stenosis. Methods: We included consecutive patients with left MCA stenosis admitted with ischemic stroke or TIA &lt;7 days from onset who underwent perfusion imaging (CT or MR perfusion) processed with RAPID software. We excluded patients with core infarct ≥ 30 mL. Perfusion mismatch was divided into three groups: mismatch volume ≥ 15 mL based on T max &gt; 6 sec delay, mismatch volume ≥ 15 mL based on T max 4-6 sec delay, and neither of the above mismatch patterns. The primary outcome was LOS, both as a continuous variable and categorical (≥ 7 days (prolonged LOS) vs. &lt;7 days). Results: 179 out of 194 patients met the inclusion criteria; mean age was 70.2 ± 15.4 years, 53.1% were women, median (IQR) NIHSS was 4 (1-9); 83.2% underwent MR perfusion; 38.5% had a mismatch volume ≥ 15 mL based on T max &gt; 6 sec and 31.3% had a mismatch volume ≥ 15 mL based on T max 4-6 sec and the median (IQR) LOS was 4 days (2-8). After adjusting for age and NIHSS, T max &gt; 6 sec mismatch definition was associated with prolonged LOS (OR 2.90 95% CI 1.06-8.18; p=0.039) but T max 4-6 sec definition was not (OR 1.45 95% CI 0.46-4.58, p=0.528), without any interaction based on perfusion imaging modality (p interaction = 0.568). We found similar associations when LOS was considered as a continuous variable for T max &gt; 6 sec (β coefficient=2.01, 95% CI 0.05-3.97, p=0.044) and T max 4-6 sec (β coefficient=1.24, 95% CI -0.85-3.34, p=0.244). In receiver operating curves, the optimal mismatch volume for T max &gt; 6 sec was 10 mL (sensitivity 0.61 and specificity 0.63) whereas for T max 4-6 sec it was 39 mL (sensitivity 0.61 specificity 0.56). Conclusion: In patients with recently symptomatic MCA stenosis, the T max &gt; 6 sec definition for mismatch, but not T max 4-6 sec, is associated with prolonged LOS. Prospective studies are needed to validate our findings and define the optimal mismatch threshold in patients with symptomatic MCA stenosis.

Impaired Distal Perfusion Predicts Length of Hospital Stay in Patients with Symptomatic Middle Cerebral Artery Stenosis.

Perfusion imaging can risk stratify patients with symptomatic intracranial stenosis. We aim to determine the association between perfusion delay and length of hospital stay (LOS) in symptomatic middle cerebral artery (MCA) stenosis patients. This is a retrospective study of consecutive patients admitted to a comprehensive stroke center over 5 years with ischemic stroke or transient ischemic attack (TIA) within 7 days of symptom onset due to MCA stenosis (50-99%) and underwent perfusion imaging. Patients were divided into three groups: mismatch volume ≥ 15 cc based on T max > 6 second delay, T max 4-6 second delay, and <4second delay. The outcome was LOS, both as a continuous variable and categorical (≥7 days [prolonged LOS] vs. <7days). We used adjusted regression analyses to determine the association between perfusion categories and LOS. One hundred and seventy eight of 194 patients met the inclusion criteria. After adjusting for age and NIHSS, T max >6 second mismatch was associated with prolonged LOS (OR 2.94 95% CI 1.06-8.18; P = .039), but T max 4-6 second was not (OR 1.45 95% CI .46-4.58, P = .528). We found similar associations when LOS was a continuous variable for T max > 6 second (β coefficient = 2.01, 95% CI .05-3.97, P = .044) and T max 4-6 second (β coefficient = 1.24, 95% CI -.85 to 3.34, P = .244). In patients with symptomatic MCA stenosis, T max > 6 second perfusion delay is associated with prolonged LOS. Prospective studies are needed to validate our findings.

Improvement of Cerebrovascular Reserve by Percutaneous Transluminal Angioplasty for Symptomatic Middle Cerebral Artery Stenosis.

The purpose of this study was to investigate the efficacy of percutaneous transluminal angioplasty (PTA) for symptomatic middle cerebral artery stenosis by analyzing cerebral blood flow (CBF). Between January 2016 and December 2018, six patients with symptomatic middle cerebral artery stenosis underwent CBF analysis by single-photon emission computed tomography (SPECT) with acetazolamide challenge before and after PTA for stenosis. They were retrospectively reviewed, and the blood flow in the area of the affected middle cerebral artery before and after angioplasty was compared. The mean stenosis rate and length of lesion before angioplasty were 76.4 ± 5.4% and 6.5 ± 2.1 mm, respectively. Balloon angioplasty without stenting was performed on all patients. The mean residual stenosis rate just after angioplasty was 45.4 ± 9.3%. No periprocedual complications developed, and there were no notable cerebral ischemic events during the postprocedural follow-up period. One patient underwent repeat angioplasty for restenosis. Although there was only a mild decrease in blood flow at rest, the cerebrovascular reserve (CVR) in the area of the affected middle cerebral artery was markedly decreased before angioplasty (mean, 3.6 ± 4.3%). After angioplasty, the CVR was significantly improved (mean, 18.0 ± 4.7%, p <0.01). PTA for symptomatic middle cerebral artery stenosis can be safely performed using appropriate interventional techniques for select patients. Reduced CVR due to stenosis can be improved after angioplasty, which may reduce the risk of cerebral ischemic events.

Application value of preoperative high-resolution magnetic resonance vessel wall imaging evaluation on symptomatic middle cerebral artery stenosis stenting

Objective To investigate the value of preoperative high-resolution magnetic resonance vessel wall imaging (HRMR-VWI) in stenosis stenting for symptomatic middle cerebral artery. Methods The clinical data of 35 patients with atherosclerotic stenosis in middle cerebral artery (MCA) M1 segment who were treated with stenting therapy (stenting angioplasty) at Department of Neurosurgery, Tianjin Huanhu Hospital from August 2011 to May 2019 were analyzed retrospectively. HRMR-VWI results were used to evaluate the location, composition and stability of plaques before operation. The mortality and morbidity at 30 days post operation were determined by clinical follow-up. The ischemic stroke and restenosis rates at 12 months post operation were confirmed by imaging follow-up. Results The preoperative HRMR-VWI of 35 patients showed that the plaques in 15 cases were located on the ventral vessel wall, those in 12 on the inferior, and those in 8 on the upper vessel wall. Seven patients had unstable plaques in the M1 segment of MCA. The stents were successfully placed in 35 patients and well adhered with smooth blood flow. Technical complications occurred in 2 (5.7%) patients. One patient (2.8%) died of cerebral hernia due to reperfusion hemorrhage in 30 days after surgery, although decompressive craniectomy and hematoma clearing were performed. One patient (2.8%) had residual neurological dysfunction. Twelve months after the operation, no ischemic stroke occurred in 34 patients, and no restenosis occurred in the 5 patients who were followed up by imaging. Conclusion HRMR-VWI has a high diagnostic value for the location and stability of plaques in stenotic sites of MCA, which could improve the safety and effectiveness of stenting of MCA M1 segment stenosis. Key words: Middle cerebral artery; Endovascular procedures; Stents; Atherosclerotic stenosis; High resolution magnetic resonance vessel wall imaging

Double stenting in T configuration with safety micro-guidewire technique in a complex middle cerebral artery stenosis

Intracranial arterial stenosis is a frequently misdiagnosed cause of ischemic stroke, associated with high rates of recurrence under medical therapy alone. Endovascular intracranial angioplasty and stenting has increasingly been used worldwide for treatment of symptomatic intracranial stenoses, despite controversial results of the first randomized trials. Lesion morphology and etiology must be considered during endovascular treatment planning. Complex morphologies can lead to serious complications during the endovascular procedure. We present a case of a symptomatic complex middle cerebral artery stenosis that was successfully treated with a double stenting in T configuration, using a safety micro-guidewire technique. During follow-up, intracranial Doppler revealed a non-significant residual stenosis and the patient remained asymptomatic.

Vascular Morphology has No Direct Relationship with Atherosclerotic Plaque Burden in Patients with Symptomatic Middle Cerebral Artery Stenosis.

The vascular morphology and the characteristics of atherosclerotic plaques in the middle cerebral artery (MCA) have not been fully studied with high-resolution magnetic resonance imaging (HR-MRI). HR-MRI was applied to investigate vascular morphology and atherosclerotic plaque in patients with symptomatic MCA stenosis. A total of 343 patients with symptomatic MCA stenosis were enrolled in this study. All the patients were examined by HR-MRI to analyze the morphology of MCA and the M1 segment (MCA-M1), the characteristics and the location of the plaques. The proportion of L-shaped MCA-M1 decreased, while the proportion of S-shaped MCAM1 increased with age. The anterior plaques were the most common in all the patients. The superior plaques were relatively common in patients with L-shaped and U-shaped MCA-M1, while the inferior plaques were relatively common in patients with inverted U-shaped and S-shaped MCAM1. Among all the plaques, the majority were isointense or heterogeneous. The MCA-M1 morphology had no direct relationship with the common risk factors of atherosclerosis and the clinical outcomes of the patients after 12 months of follow up. The morphology of MCA-M1 is not directly related to the plaque burden or the degree of stenosis in patients with symptomatic MCA stenosis. The morphology of MCA-M1 is not associated with the risk factors of atherosclerosis, or the clinical outcomes of the patients.

Perfusion and plaque evaluation to predict recurrent stroke in symptomatic middle cerebral artery stenosis

Background and purposeWe investigated the baseline demographics of patients with severe unilateral atherosclerotic stenosis of the middle cerebral artery (MCA) using multimodal MRI and evaluated the haemodynamic impairments and plaque...

Combination of Plaque Characteristics, Pial Collaterals, and Hypertension Contributes to Misery Perfusion in Patients With Symptomatic Middle Cerebral Artery Stenosis.

Atherosclerotic plaque in the middle cerebral artery (MCA) is linked to ischemic stroke events, but the relationship between plaque characteristics and cerebral perfusion is unclear. To investigate MCA plaque characteristics between intracranial atherosclerotic patients with and without hypoperfusion area, and to identify the variables affecting hypoperfusion volume. Retrospective. Seventy-one patients with MCA stenosis (>50%), and all with ischemic onset in recent 2 weeks. 3.0T MRI / diffusion-weighted imaging (DWI), time-of-flight magnetic resonance angiography (TOF-MRA), inversion-recovery prepared sampling perfection with application-optimized contrast using different flip angle evolutions (IR-SPACE), dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI). Plaque characteristics including eccentric index (EI), eccentricity, plaque length, and enhancement on MCA were measured on IR-SPACE. Pial collaterals (PCs) were evaluated on axial TOF-MRA source images. Time-to-maximum (Tmax) maps with a threshold more than 6 seconds were assessed by rapid processing of perfusion and diffusion (RAPID) software. Two independent-samples t-tests, Mann-Whitney U-test, chi-square test, Z test, univariate and multivariate logistic analysis, and receiver operating characteristic (ROC) curve were used. Patients with hypoperfusion had fewer eccentric plaque, lower EI, longer plaque length, and poor PCs compared with those without (P = 0.002, 0.016, 0.003, and 0.001). Eccentricity, plaque length, PCs, and hypertension were the factors independently associated with the occurrence of hypoperfusion after adjustment for risk factors of cerebrovascular disease (P = 0.014, 0.017, 0.035, and 0.018). The area under the curve (AUC) (95% confidence interval) was 0.865 (0.763-0.934) for a combination of the above four variables, which was significantly higher than any variable alone (P < 0.001, 0.016, < 0.001, and < 0.001). Patients with lower EI, concentric morphology, and grade 2 enhancement trended to have larger hypoperfusion volume (P = 0.028, 0.037, and 0.009). Plaque eccentricity, plaque length, PCs, and hypertension showed an association with the occurrence of hypoperfusion. 4 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:195-204.

A comparison of transcranial Doppler and magnetic resonance imaging for long term changes in middle cerebral artery stenosis

ObjectivesIntracranial arterial stenosis may progress or regress, of which the diagnosis is important to predict the risk of stroke or to evaluate the response of treatment. Transcranial Doppler (TCD) seems to be useful for this purpose, however, optimal diagnostic criteria have not been validated yet. Our study was designed to compare TCD changes with magnetic resonance angiography (MRA) to validate optimal TCD criteria for progression or regression of middle cerebral artery (MCA). Patients and methodsWe prospectively enrolled patients who visited our neurology department due to MCA stenosis on TCD examination. Brain MRA was used to identify patients with stenosis of the same site of MCA. Progression or regression was defined by change of MRA grading (normal, mild, moderate, severe or occlusion). Various criteria of mean flow velocity (MFV) difference and percent change were assessed. To register more patients for reliable analysis, additional patients with the same inclusion criteria were recruited retrospectively. All patients enrolled in the study were symptomatic or asymptomatic atherosclerotic MCA stenosis. ResultsEighteen patients were enrolled and 21 MCAs with completed follow-up TCD and MRA were analyzed (mean age 68.4 years, mean follow-up 17.8 months). In addition, 40 MCAs from 30 retrospective patients were also analyzed (mean age 65.7 years, mean follow-up 22.3 months). Among assessed criteria, the most optimal cutoff value for the progression of stenosis was 20 cm/s, at which the sensitivity and specificity were 100% and 91% in prospective group, and were 80% and 93% in retrospective group. In the % difference analysis, prospective group showed sensitivity 100% and specificity 82% in the 20% cutoff. The retrospective group showed sensitivity 80% and specificity 93% in the 15% cutoff. However, results of the regression group were not consistent. ConclusionsDiagnosis of progression of MCA stenosis with serial TCD examination is feasible and MFV change of 20 cm/s and % change of 15–20% are suggested as optimal cut-off value but not in the regression. These criteria would be useful for the clinical research and real-world practice.

Quantitative score of the vessel morphology in middle cerebral artery atherosclerosis

BackgroundWe aimed to quantitatively assess the vessel morphology of middle cerebral artery (MCA) atherosclerosis and explore its value in discriminating plaque types. MethodsPatients were selected from a high-resolution magnetic resonance imaging (HRMRI) study from January 2007 to December 2015. One hundred and three patients with acute cerebral infarcts due to MCA stenosis (>50%) and eighty-nine patients with asymptomatic MCA stenosis (>50%) were included. Quantitative measurements of MCA morphology, including lumen area, outer-wall and wall area at stenotic site and reference site, stenotic degree, plaque length, remodeling index and plaque eccentricity, were performed on HRMRI with observers blinded to clinical presentations. Firth's penalized logistic regression analysis was used to construct a symptomatic plaque score (SPS) model. Then, the HRMRI data of 39 patients prospectively enrolled from January 2016 to January 2017 were used to validate the SPS model. ResultsThe HRMRI data of 103 patients with symptomatic MCA stenosis and 89 patients with asymptomatic MCA stenosis in the construction cohort were analyzed. Four main factors were found to be associated with symptomatic plaques: stenotic lumen area ≥ 2.28 mm2, stenotic wall area ≥ 8.88 mm2, plaque length and presence of an eccentric plaque. Summation of each logistic regression coefficient multiplying the corresponding score produced the SPS with an area under curve (AUC) of 0.890 on receiver operating characteristics analysis. Validation of the score of 39 plaques (19 symptomatic and 20 asymptomatic) revealed an AUC of 0.862, confirming the continued diagnostic ability. When the data were pooled in all 235 plaques, the optimal cutoff score of discriminating symptomatic and asymptomatic plaques was 2.79 (SPS ≥ 2.79 indicating a symptomatic plaque) with AUC = 0.886, sensitivity 81.1% and specificity 80.5%. ConclusionsThe quantitative analysis of MCA morphology can independently and accurately discriminate plaque types, suggesting its close association with the underlying pathophysiology. Further prospective studies are required to verify whether the SPS model is clinically valuable in monitoring plaque progression and assessing the vulnerability.

Balloon-Mounted versus Self-Expanding Stent Outcomes in Symptomatic Middle Cerebral Artery Stenosis Combined with Poor Collaterals in China: A Multicenter Registry Study

To compare the technical and 1-year clinical outcome in balloon-mounted versus self-expanding stenting for symptomatic severe stenosis of the middle cerebral artery combined with poor collaterals in China. Ninety-one patients with severe middle cerebral artery atherosclerotic stenosis combined with poor collaterals were recruited in the study. Balloon-mounted stent or self-expanding stent were selected to treat patients following a guideline. The baseline characteristics, cerebral angiography, and outcomes were compared between the patients treated with balloon-mounted stent and self-expanding stent. The mean degree of stenosis was 85.5% ± 6.37% in the balloon-mounted stenting group and 85.4% ± 7.73% in the self-expanding stenting group before treatment (P= 0.930). A longer operative time occurred in patients treated with self-expanding stent than in those treated with balloon-mounted stent (96.7 vs. 68.6 minutes, respectively; P= 0.002). Patients with self-expanding stent had a higher rate of residual stenosis than those with balloon-mounted stent (67.3% vs. 38.9%, respectively; P= 0.014). The patients in balloon-mounted stenting group was less likely to have restenosis (6.1% vs. 26.5%, P= 0.019) and had a lower degree of stenosis (5.0% ± 0.0% vs. 26.9% ± 29.2%, P= 0.019) compared with patients in the self-expanding stenting group. During the 1-year follow-up, the recurrence rate of ischemic stroke, transient ischemic attack, hemorrhage stroke, and death was not significantly different between the 2 groups (1/33 vs. 2/49, P= 0.804; 1/33 vs. 1/49, P= 0.776; 0/33 vs. 2/49, P= 0.240; 1/33 vs. 0/49, P= 0.220, respectively). Balloon-mounted stents may have a shorter operative time and lower restenosis occurrence than self-expanding stents. No significant difference in 1-year outcome was observed between the 2 groups.

Hemodynamic ischemia of the anterior choroidal artery and reversal by carotid artery stenting 10 years after ipsilateral superficial temporal artery-middle cerebral artery bypass for symptomatic left middle cerebral artery stenosis.

The pathogenesis of anterior choroidal artery (AChA) territory infarction includes various mechanisms, but hemodynamic causes are rare and difficult to diagnose. 77- year-old man, who had moderate left ICA stenosis and he had treated with STA-MCA bypass surgery for severe symptomatic left MCA stenosis 10 years earlier, was admitted with right hemiparesis and confused state. On admission, magnetic resonance imaging and angiography demonstrated patent bypass, but severe stenosis of left ICA with no opacification of the left AChA and A1 portion of the left ACA. Diffusionweighted imaging demonstrated ischemic lesion in the left corona radiata. Together with clinical findings, hemodynamic ischemia of the AChA region was suspected and left carotid artery stenting resulted in prompt improvement of symptoms. Hemodynamic ischemia of the AChA territory is rare, however, should be considered as a potential target of treatment when the ipsilateral ICA, A1 and M1 show stenoocclusive lesions.

Balloon-expandable stents for treatment of symptomatic middle cerebral artery stenosis: Clinical outcomes during long-term follow-up.

Insertion of a balloon-expandable stent (BES) in patients with symptomatic intracranial atherosclerosis is a treatment option for reperfusion therapy. In this study, we retrospectively reviewed clinical outcomes during long-term follow-up after insertion of balloon-expandable stents in patients with symptomatic middle cerebral artery (MCA) stenosis. Institutional review board approval was obtained for retrospective review of patient data. Thirty-four patients (15 men, 19 women; median age, 67.5 years) with symptomatic MCA stenosis underwent balloon-expandable stent insertion between June 2008 and December 2010. Patient records were reviewed for angiographic findings and clinical outcomes during long-term follow-up. Of these patients, 22 presented with acute ischemic stroke with underlying MCA atherosclerosis and had good clinical outcomes (modified Rankin Scale score (mRS): 0-2) after reperfusion therapy. Indications for stenting for the remaining 12 patients were recurrent transient ischemic attacks (TIAs) refractory to medical therapy and MCA stenosis greater than 70%. During the poststenting follow-up period, which ranged from 61 to 108 months (median, 67.5 months), a TIA occurred in five patients. Of these five patients, one experienced a complete reocclusion of the MCA stent, and three had symptomatic restenosis. The remaining 29 patients did not experience any further ischemic events or restenosis during the follow-up period. In our study, treatment with balloon-expandable stents in patients with symptomatic MCA stenosis resulted in low recurrence rates for both ischemic events and restenosis during long-term follow-up.

Long-Term Outcome of Balloon Angioplasty Without Stenting for Symptomatic Middle Cerebral Artery Stenosis

A recent randomized controlled trial demonstrated that aggressive medical management was superior to angioplasty with stenting for intracranial stenosis. The purpose of this study was to assess initial and long-term outcomes of balloon angioplasty without stenting for symptomatic middle cerebral artery (MCA) stenosis. We retrospectively analyzed the clinical data of 72 patients (mean age, 58.9 years old) with 84 balloon angioplasties without stenting for high-grade (>70%) atherosclerotic stenosis of the main trunk of the MCA. All patients had experienced recurrent transient ischemic attack or minor stroke resistant to medical treatment. We assessed perioperative and long-term outcomes such as restenosis and the recurrence of strokes. The follow-up period was a median of 63 months (range, 6-171 months). Balloon angioplasty was successful in 97% of procedures. During the 30-day perioperative period, a total of 3 patients suffered from stroke (4.2%) without death. A total of 23 (31.9%) patients had restenosis at a time point that varied from 6 to 111 months. Diabetes mellitus (DM) was noted significantly more often in the restenosis group (39%) than in the nonrestenosis group (13%). Multivariate logistic regression analysis revealed DM (odds ratio, 4.84; 95% confidence interval, 1.196-19.62; P = .027) as an independent predictor of restenosis. Restenosis and DM were indicated as independent predictors of the recurrence of ischemic stroke and transient ischemic attack. Balloon angioplasty without stenting for symptomatic MCA stenosis can be performed with a high successful rate and a low risk of complications. Long-term outcome data suggest that this procedure reduces the risk of further strokes.