BACKGROUND: The accuracy of traditional knee MR imaging in diagnosing anterior cruciate ligament tears, especially partial tears, is relatively low, which may lead to misdiagnosis and missed diagnosis. This study aimed to assess the diagnostic performance of a novel imaging method, high-resolution oblique coronal MRI at an optimal flexed-knee Angle, for ACL tears.
METHODS: 50 healthy volunteers were scanned with a scan-assisted device for the optimal flexion angle of ACL. For 92 knee trauma patients selected strictly according to inclusion and exclusion criteria, conventional extended-knee scans (control group) and high-resolution oblique coronal scans based on the optimal flexed-knee angle (experimental group) were conducted. Two observers rated ACL visibility blindly on a 5-point scale. Arthroscopy-defined outcomes determined diagnostic metrics for each method and sensitivity, specificity, positive predictive value, negative predictive value and accuracy were calculated.
RESULTS: The average optimal flexion angle for healthy volunteers was approximately 30° (30.3° ± 5.0°). Imaging demonstrated complete visualization of the ACL in 96.7% of images in the experimental group versus 12.0% in the control group. The diagnostic indicators of the experimental group surpassed those of the control group: sensitivity (94.9% vs. 76.3%), specificity (97.0% vs. 81.8%), positive predictive value (98.2% vs. 88.2%), negative predictive value(91.4% vs. 65.9%), and accuracy (95.7% vs. 78.3%). ROC analysis indicated superior diagnostic performance in the experimental group, with an AUC of 0.945 compared with 0.776 for the control group (p < 0.0001).
CONCLUSIONS: High-resolution oblique coronal imaging at the optimal 30° flexed-knee angle improved ACL visualization and diagnostic performance compared with conventional techniques.

UNASSIGNED: To identify the correlation between thrombosis and atherosclerosis in systemic lupus erythematosus (SLE) patients with antiphospholipid antibodies (aPLs) (SLE/aPLs) through high-resolution magnetic resonance imaging (HR-MRI) of the carotid artery.
UNASSIGNED: A single-center, cross-sectional study was conducted. We collected consecutive patients with SLE/aPLs and healthy controls who underwent carotid HR-MRI examinations. The morphometric characteristics of the common carotid artery (CCA), internal carotid artery (ICA), external carotid artery (ECA), and carotid bulb (Sinus) were measured, and the differences in morphometric parameters between different groups were analyzed.
UNASSIGNED: A total of 144 carotid arteries were analyzed. Compared with the control group, the wall area, wall thickness (WT and WTmax), and normalized wall index of CCA, ICA, ECA, and Sinus were increased in patients with SLE/aPLs, and the total vascular area (TVA) of CCA, ICA, and Sinus, and the bifurcation angle (BIFA) of ICA-ECA were also increased. A negative lupus anticoagulant (LAC) (with or without positive anticardiolipin antibody (aCL) or anti-β2glycoprotein antibody (aβ2GPI)) contributed to illustrating lower increased TVA and thickened vessel walls of CCA and ICA in SLE/aPLs patients without thrombotic events. Logistic regression analysis showed that WTmaxSinus and WTmaxGlobal were independent risk factors for thrombotic events in SLE/aPLs patients. The receiver operator characteristic curve showed that the cut-off value of WTmaxSinus was 2.855 mm, and WTmaxGlobal was 3.370 mm.
UNASSIGNED: HR-MRI ensures the complete and accurate measurement of carotid morphometric parameters. Compared with the control group, the carotid artery in patients with SLE/aPLs is mainly characterized by diffusely thickened vessel walls, and the patients with thrombotic events showed additional higher vascular area of CCA and ICA, and BIFA of ICA-ECA without significant change in lumen area. The carotid arteries of SLE/aPLs patients with thrombotic events exhibited significant vessel wall thickening in all segments except ECA compared to those without thrombotic events. LAC-negative and non-thrombotic events distinguish relatively early atherosclerosis in the carotid arteries in patients with SLE/aPLs. Patients with SLE/aPLs that possess circumscribed thickened carotid vessel walls (>3.370 mm), particularly thickened at the Sinus (>2.855 mm), may require management strategies for the risk of thrombotic events.

BACKGROUND: There has been an increasing demand for imaging methods that provide a comprehensive evaluation of intracranial clot and collateral circulation, which are helpful for clinical decision-making and predicting functional outcomes. We aimed to quantitatively evaluate acute intracranial clot burden and collaterals on high-resolution magnetic resonance imaging (HR-MRI).
METHODS: We analyzed acute ischemic stroke patients with internal carotid artery or middle cerebral artery occlusion in a prospective multicenter study. The clot burden was scored on a scale of 0-10 based on the clot location on HR-MRI. The collateral score was assigned on a scale of 0-3 using the minimum intensity projection from HR-MRI. Uni- and multivariable logistic regression analyses were performed to assess their correlation with clinical outcome (modified Rankin Scale >2 at 90 days). Thresholds were defined to dichotomize into low- and high-score groups, and predictive performances were assessed for clinical and radiologic outcomes.
RESULTS: Ninety-nine patients (mean age of 60.77 ± 11.54 years) were included in the analysis. The interobserver correlation was 0.89 (95% CI: 0.77-0.95) for the clot burden score and 0.78 (95% CI: 0.53-0.90) for the collateral score. Multivariable logistic regression analysis demonstrated that the collateral score (odds ratio: 0.41, 95% CI: 0.19-0.90) was significantly associated with clinical outcomes. A better functional outcome was observed in the group with clot burden scores greater than 7 (p = 0.011). A smaller final infarct size and a higher diffusion-weighted imaging-based Alberta Stroke Program Early Computed Tomography Score were observed in the group with collateral scores greater than 1 (all p < 0.05).
CONCLUSIONS: HR-MRI offers a new tool for quantitative assessment of clot burden and collaterals simultaneously in future clinical practices and research endeavors.

In vivo studies on association between wall shear stress (WSS) and intracranial plaque are deficient. Based on the three-dimensional T1-weighted high-resolution magnetic resonance imaging (3DT1 HR-MRI) data of patients with low-grade stenotic (<50%) atherosclerotic middle cerebral artery (MCA) and subjects with normal MCA, we built a three-dimensional reconstructed WSS model by computational fluid dynamics (CFD) technique. Three-dimensional registration of the CFD model to the HR-MRI was performed with projections based on the resolution and thickness of the images. The relationships between the WSS at each side of the vessel wall and plaque location were analyzed. A total of 94 MCA plaques from 43 patients and 50 normal MCAs were analyzed. In the normal MCAs, WSS was lower at the ventral-inferior wall than at the dorsal-superior wall (proximal segment, p < 0.001; middle segment, p < 0.001) and lower at the inner wall than at the outer wall of the MCA curve (p < 0.001). In atherosclerotic MCAs, similar low WSS regions were observed where plaques developed. The WSS ratio of the ventral-inferior wall to the dorsal-superior wall in atherosclerotic MCAs was lower than that in normal MCAs (p = 0.002). The WSSinner-outer ratio in atherosclerotic MCAs was lower than that in normal MCAs (p = 0.002). Low WSS was associated with MCA atherosclerosis formation and occurred mainly at the ventral-inferior wall, which was anatomically opposite the orifices of penetrating arteries, and at the inner wall of the MCA curve. Overall, the results were well consistent with the low WSS theory in atherosclerosis formation. The reconstructed WSS model is a promising novel method for assessing an individualized vascular profile once validated by further studies.

UNASSIGNED: This study aimed to investigate the predictive value of the thyroid-stimulating hormone to high-density lipoprotein cholesterol ratio (THR) in identifying specific vulnerable carotid artery plaques.
UNASSIGNED: In this retrospective analysis, we included 76 patients with carotid plaques who met the criteria for admission to Zhejiang Hospital from July 2019 to June 2021. High-resolution magnetic resonance imaging (HRMRI) and the MRI-PlaqueView vascular plaque imaging diagnostic system were utilized to analyze carotid artery images for the identification of specific plaque components, including the lipid core (LC), fibrous cap (FC), and intraplaque hemorrhage (IPH), and recording of the area percentage of LC and IPH, as well as the thickness of FC. Patients were categorized into stable plaque and vulnerable plaque groups based on diagnostic criteria for vulnerable plaques derived from imaging. Plaques were categorized based on meeting one of the following consensus criteria for vulnerability: lipid core area over 40% of total plaque area, fibrous cap thickness less than 65 um, or the presence of intraplaque hemorrhage. Plaques meeting the above criteria were designated as the LC-associated vulnerable plaque group, the IPH-associated group, and the FC-associated group. Multivariate logistic regression was employed to analyze the factors influencing carotid vulnerable plaques and specific vulnerable plaque components. Receiver operating characteristic (ROC) curves were used to assess the predictive value of serological indices for vulnerable carotid plaques.
UNASSIGNED: We found that THR (OR = 1.976; 95% CI = 1.094-3.570; p = 0.024) and TSH (OR = 1.939, 95% CI = 1.122-3.350, p = 0.018) contributed to the formation of vulnerable carotid plaques. THR exhibited an area under the curve (AUC) of 0.704 (95% CI = 0.588-0.803) (p = 0.003), and the AUC for TSH was 0.681 (95% CI = 0.564-0.783) (p = 0.008). THR was identified as an independent predictor of LC-associated vulnerable plaques (OR = 2.117, 95% CI = 1.064-4.212, p = 0.033), yielding an AUC of 0.815. THR also demonstrated diagnostic efficacy for LC-associated vulnerable plaques.
UNASSIGNED: This study substantiated that THR and TSH have predictive value for identifying vulnerable carotid plaques, with THR proving to be a more effective diagnostic indicator than TSH. THR also exhibited predictive value and specificity in the context of LC-associated vulnerable plaques. These findings suggest that THR may be a promising clinical indicator, outperforming TSH in detecting specific vulnerable carotid plaques.

BACKGROUND: Relatively little is known about the plaque characteristics of border-zone infarcts and how they differ between cortical border-zone (CBZ) and internal border-zone (IBZ) infarcts.
METHODS: We conducted a retrospective observational cohort study of patients with intracranial atherosclerotic disease who underwent high-resolution magnetic resonance imaging (HR-MRI) examination. Individuals with border-zone infarcts in the middle cerebral artery (MCA) territory, detected by diffusion-weighted imaging, were enrolled. Plaque morphological and compositional parameters of both IBZ and CBZ groups were compared. Independent predictors were identified using a binary logistic regression model, and the sensitivity and specificity of the model were assessed using a receiver operating characteristic curve. Kaplan-Meier survival analysis further explored differences in stroke recurrence between BZ patients with mono or dual antiplatelet therapy.
RESULTS: We reviewed 101 symptomatic patients with border-zone infarcts (BZ) within the MCA territory in the study. Out of the patients meeting the imaging eligibility criteria, we detected 34 cases with isolated IBZ, 23 cases with isolated CBZ, and six cases with both IBZ and CBZ infarcts. Those with IBZ infarcts had a higher plaque burden than those without (p < 0.001), and those with CBZ infarcts exhibited a complicated plaque less frequently than those without (37.9% vs 67.6%, p = 0.018). In those with isolated IBZ or CBZ infarcts, plaque burden was independently associated with isolated IBZ infarcts (odd ratio=1.08; 95% CI, 1.02-1.15; p = 0.023). During the median follow-up period of 37 (27, 50) months, 13.8% of patients receiving early dual antiplatelet treatment and 30.4% of those on single antiplatelet therapy experienced stroke recurrence (p = 0.182).
CONCLUSIONS: Intracranial atherosclerotic plaque morphology and composition differ between patients with IBZ and those with CBZ infarcts. Higher plaque burden is more associated with IBZ infarcts.

OBJECTIVE: The clinical characteristics and mechanisms of stroke caused by anterior circulation atherosclerotic plaques (ACAPs) and posterior circulation atherosclerotic plaques (PCAPs) are distinct. We aimed to compare the differences in vulnerability, morphology, and distribution between ACAPs and PCAPs based on hign-resolution magnetic resonance imaging (HR-MRI).
METHODS: The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang database were retrieved from inception through May 2023. Meta-analysis was performed by R 4.2.1 software. The quality of the literature was assessed by the Agency for Healthcare Research and Quality (AHRQ). Subgroup analysis was conducted to explore the heterogeneity of the pooled results.
RESULTS: There were a total of 13 articles, including 1194 ACAPs and 1037 PCAPs. The pooled estimates demonstrated that the incidence of intraplaque hemorrhage in the PCAPs was higher (OR 1.72, 95%CI 1.35-2.18). The plaque length (SMD 0.23, 95%CI 0.06-0.39) and remodeling index (SMD 0.29, 95%CI 0.14-0.44) of PCAPs were larger than those in ACAPs. However, there were no evident differences in significant enhancement or stenosis degree between the two groups.
CONCLUSIONS: There were more unstable features in PCAPs, highlighting an elevated risk of recurrent ischemic stroke in the posterior circulation. Furthermore, PCAPs were prone to developing penetrating artery disease due to their wider distribution. Nevertheless, posterior circulation arteries exhibited a greater propensity for outward remodeling, which may lead treatment team to miss the optimal intervention stage by being overlooked on angiographic detection.

OBJECTIVE: Intracranial vessel wall enhancement (VWE) on high-resolution magnetic resonance imaging (HRMRI) is associated with the progression and poor prognosis of moyamoya disease (MMD). This study assessed potential risk factors for VWE in MMD.
METHODS: We evaluated MMD patients using HRMRI and traditional angiography examinations. The participants were divided into VWE and non-VWE groups based on HRMRI. Logistic regression was performed to compare the risk factors for VWE in MMD. The incidence of cerebrovascular events of the different subgroups according to risk factors was compared using Kaplan-Meier survival and Cox regression.
RESULTS: We included 283 MMD patients, 84 of whom had VWE on HRMRI. The VWE group had higher modified Rankin Scale scores at admission (p = 0.014) and a higher incidence of ischaemia and haemorrhage (p = 0.002) than did the non-VWE group. Risk factors for VWE included the ring finger protein 213 (RNF213) p.R4810K variant (odds ratio [OR] 2.01, 95% confidence interval [CI] 1.08-3.76, p = 0.028), hyperhomocysteinaemia (HHcy) (OR 5.08, 95% CI 2.34-11.05, p < 0.001), and smoking history (OR 3.49, 95% CI 1.08-11.31, p = 0.037). During the follow-up of 63.9 ± 13.2 months (median 65 months), 18 recurrent stroke events occurred. Cox regression showed that VWE and the RNF213 p.R4810K variant were risk factors for stroke.
CONCLUSIONS: The RNF213 p.R4810K variant is strongly associated with VWE and poor prognosis in MMD. HHcy and smoking are independent risk factors for VWE.
CONCLUSIONS: Vessel wall enhancement in moyamoya disease is closely associated with poor prognosis, especially related to the ring finger protein 213 p.R4810K variant, hyperhomocysteinaemia, and smoking, providing crucial risk assessment information for the clinic.
CONCLUSIONS: • The baseline presence of vessel wall enhancement is significantly associated with poor prognosis in moyamoya disease. • The ring finger protein 213 p.R4810K variant is strongly associated with vessel wall enhancement and poor prognosis in moyamoya disease. • Hyperhomocysteinaemia and smoking are independent risk factors for vessel wall enhancement in moyamoya disease.

BACKGROUND: This study aims to determine how atherosclerotic plaque prevalence and characteristics vary between individuals residing year-round at middle and high altitudes who have intracranial atherosclerotic disease.
METHODS: We conducted a retrospective analysis of patient data from our hospital, focusing on individuals with cerebrovascular symptoms who underwent high-resolution vessel wall imaging (HR-VWI). Patients who had lived at an altitude of <2500 meters for an extended period were classified in group A (n = 91), while those residing at an altitude of ≥2500 meters were placed in group B (n = 75). We examined the differences in plaque prevalence and characteristics between these two groups.
RESULTS: The detection rate of basilar artery plaque was higher in group A compared to group B (16% vs. 7.6%, p = 0.036). Conversely, the detection rate of anterior cerebral artery plaque was significantly lower in group A than in group B (4% vs. 11.8%, p = 0.016). The eccentricity index (EI) was greater in group B than in group A (0.72 ± 0.11 vs. 0.68 ± 0.12, p = 0.012). The prevalence of intraplaque hemorrhage (IPH) was lower in group B than in group A (39.5% vs. 58.7%, p = 0.002).
CONCLUSIONS: IPH prevalence was lower in patients residing at high altitudes than in those residing at middle altitudes. However, patients living at high altitudes had a higher EI compared to those residing at middle altitudes. These findings underscore the presence of disparities in the prevalence and characteristics of intracranial atherosclerotic plaques between individuals residing at medium and high altitudes. It is essential to account for these distinctions when diagnosing plaques.

BACKGROUND: The association between the degree of plaque enhancement and ischemic brain stroke recurrence remains unclear. We aimed to establish models to predict plaque enhancement and stroke recurrence.
METHODS: Seventy-eight participants with acute ischemic brain stroke due to intracranial arterial stenosis were recruited and divided into high enhancement (HE) and non-HE groups. The relationship between imaging characteristics (degree of stenosis, minimal lumen area, intraplaque hemorrhage, and plaque burden) and the degree of plaque contrast enhancement was analyzed. Inflammatory cytokine expression was examined by flow cytometry. Independent predictors of stroke recurrence were investigated via multivariate Cox proportional hazards regression analysis. Nomogram was used to construct a prediction model. Harrell\'s concordance indices (c-indices) and calibration curves were used to assess the discrimination of the nomogram. A risk prediction nomogram for prognosis was constructed.
RESULTS: Thirty-three participants were assigned to the HE group and 45 to the non-HE group. The degree of stenosis and plaque burden in the HE group was higher than that in the non-HE group (P<0.05). Multiple linear regression analysis showed the degree of stenosis was associated with HE (β=0.513; P=0.000). After adjusting for confounding factors, age (HR=1.115; 95%CI=1.034-1.203, P=0.005) and HE plaques (HR=10.457; 95%CI=1.176-93.018; P=0.035) were independent risk factors of stroke recurrence, whereas cytokine levels were not statistically significant between two group.
CONCLUSIONS: HE of intracranial atherosclerosis plaques is an independent factor for ischemic brain stroke recurrence.