BACKGROUND AND PURPOSE: 3D high-resolution black-blood MRI or MR vessel wall imaging allows evaluation of the intracranial arterial wall and extraluminal pathology. We investigated the diagnostic accuracy and reliability of black-blood MRI for the intraluminal detection of large-vessel arterial occlusions. MATERIALS AND METHODS: We retrospectively identified patients with intracranial arterial occlusions, confirmed by CTA or DSA, who also underwent 3D black-blood MRI with nonenhanced and contrast-enhanced T1 sampling perfection with application-optimized contrasts by using different flip angle evolution (T1 SPACE) sequences. Black-blood MRI findings were evaluated by 2 independent and blinded neuroradiologists. Large-vessel intracranial arterial segments were graded on a 3-point scale (grades 0–2) for intraluminal baseline T1 hyperintensity and contrast enhancement. Vessel segments were considered positive for arterial occlusion if focal weak (grade 1) or strong (grade 2) T1-hyperintense signal and/or enhancement replaced the normal intraluminal black-blood signal. RESULTS: Thirty-one patients with 38 intracranial arterial occlusions were studied. The median time interval between black-blood MRI and CTA/DSA reference standard studies was 2 days (range, 0–20 days). Interobserver agreement was good for T1 hyperintensity (κ = 0.63) and excellent for contrast enhancement (κ = 0.89). High sensitivity (100%) and specificity (99.8%) for intracranial arterial occlusion diagnosis was observed with either intraluminal T1 hyperintensity or contrast-enhancement imaging criteria on black-blood MRI. Strong grade 2 intraluminal enhancement was maintained in >80% of occlusions irrespective of location or chronicity. Relatively increased strong grade 2 intraluminal T1 hyperintensity was noted in chronic/incidental versus acute/subacute occlusions (45.5% versus 12.5%, P = .04). CONCLUSIONS: Black-blood MRI with or without contrast has high diagnostic accuracy and reliability in evaluating intracranial large-vessel arterial occlusions with near-equivalency to DSA and CTA.

Objectives: We sought to determine the effect of acute electrolyte and osmolar shifts on brain volume and neurologic function in patients with liver failure and severe hepatic encephalopathy. Design: Retrospective analysis of brain CT scans and clinical data. Setting: Tertiary care hospital ICUs. Patients: Patients with acute or acute-on-chronic liver failure and severe hepatic encephalopathy. Interventions: Clinically indicated CT scans and serum laboratory studies. Measurements and Main Results: Change in intracranial cerebrospinal fluid volume between sequential CT scans was measured as a biomarker of acute brain volume change. Corresponding changes in serum osmolality, chemistry measurements, and Glasgow Coma Scale were determined. Associations with cerebrospinal fluid volume change and Glasgow Coma Scale change for initial volume change assessments were identified by Spearman’s correlations (r _s) and regression models. Consistency of associations with repeated assessments was evaluated using generalized estimating equations. Forty patients were included. Median baseline osmolality was elevated (310 mOsm/Kg [296–321 mOsm/Kg]) whereas sodium was normal (137 mEq/L [134–142 mEq/L]). Median initial osmolality change was 9 mOsm/kg (5–17 mOsm/kg). Neuroimaging consistent with increased brain volume occurred in 27 initial assessments (68%). Cerebrospinal fluid volume change was more strongly correlated with osmolality (r = 0.70; p = 4 × 10^–7) than sodium (r = 0.28; p = 0.08) change. Osmolality change was independently associated with Glasgow Coma Scale change (p = 1 × 10^–5) and cerebrospinal fluid volume change (p = 2.7 × 10^–5) in initial assessments and in generalized estimating equations using all 103 available assessments. Conclusions: Acute decline in osmolality was associated with brain swelling and neurologic deterioration in severe hepatic encephalopathy. Minimizing osmolality decline may avoid neurologic deterioration.

Little is known about the prognostic significance of specific characteristics of magnetic resonance imaging (MRI) measured plaque in the superficial femoral artery (SFA). Associations of MRI-measured plaque quantity, lumen area, and plaque composition in the SFA with subsequent mobility loss were studied in people with lower extremity peripheral artery disease (PAD). Participants with an ankle–brachial index (ABI) < 1.00 were identified from Chicago medical centers and underwent direct visualization of atherosclerotic plaque in the SFA using MRI. Participants were followed annually for up to 4 years. Mobility loss was defined as becoming unable to walk up and down a flight of stairs or walk one-quarter of a mile without assistance among participants without mobility impairment at baseline. Analyses adjusted for age, sex, race, comorbidities, ABI, physical activity, and other confounders. Of 308 PAD participants without baseline mobility impairment, 100 (32.5%) developed mobility loss during follow-up. Compared to the lowest mean plaque area tertile at baseline, participants in the highest (worst) plaque area tertile had a higher rate of mobility loss (hazard ratio (HR) = 2.08, 95% confidence interval (CI) = 1.14–3.79, p = 0.018). Compared to the highest mean lumen area tertile, the smallest (worst) mean lumen area tertile was associated with greater mobility loss (HR = 2.18, 95% CI = 1.20–3.96, p = 0.011). Neither lipid rich necrotic core nor calcium in the SFA were associated with mobility loss. In conclusion, greater plaque quantity and smaller lumen area in the proximal SFA, but not lipid rich necrotic core or calcium, were associated with higher mobility loss in people with PAD.

Background and Purpose: Brain cavernous angiomas with symptomatic hemorrhage (CASH) have a high risk of neurological disability from recurrent bleeding. Systematic assessment of baseline features and multisite validation of novel magnetic resonance imaging biomarkers are needed to optimize clinical trial design aimed at novel pharmacotherapies in CASH. Methods: This prospective, multicenter, observational cohort study included adults with unresected, adjudicated brain CASH within the prior year. Six US sites screened and enrolled patients starting August 2018. Baseline demographics, clinical and imaging features, functional status (modified Rankin Scale and National Institutes of Health Stroke Scale), and patient quality of life outcomes (Patient-Reported Outcomes Measurement Information System-29 and EuroQol-5D) were summarized using descriptive statistics. Patient-Reported Outcomes Measurement Information System-29 scores were standardized against a reference population (mean 50, SD 10), and one-sample t test was performed for each domain. A subgroup underwent harmonized magnetic resonance imaging assessment of lesional iron content with quantitative susceptibility mapping and vascular permeability with dynamic contrast-enhanced quantitative perfusion. Results: As of May 2020, 849 patients were screened and 110 CASH cases enrolled (13% prevalence of trial eligible cases). The average age at consent was 46±16 years, 53% were female, 41% were familial, and 43% were brainstem lesions. At enrollment, ≥90% of the cohort had independent functional outcome (modified Rankin Scale score ≤2 and National Institutes of Health Stroke Scale score 30% of patients (EuroQol-5D). Patients had significantly worse Patient-Reported Outcomes Measurement Information System-29 scores for anxiety ( P =0.007), but better depression ( P =0.002) and social satisfaction scores ( P =0.012) compared with the general reference population. Mean baseline quantitative susceptibility mapping and permeability of CASH lesion were 0.45±0.17 ppm and 0.39±0.31 mL/100 g per minute, respectively, which were similar to historical CASH cases and consistent across sites. Conclusions: These baseline features will aid investigators in patient stratification and determining the most appropriate outcome measures for clinical trials of emerging pharmacotherapies in CASH.

Background: In patients with mild ischemic stroke, small but eloquent infarcts may have devastating effects, particularly on health-related quality of life. Aim: This study investigates the association between acute infarct location and three-month health-related quality of life in patients with mild ischemic stroke. Methods: We evaluated consecutively enrolled patients from a single center between August 2012 and July 2013. Our primary outcome at three months was impairment in any health-related quality of life domain (upper extremity, lower extremity, executive function, and general concerns) defined by a T-score <45. We analyzed the association between acute infarct locations and impaired health-related quality of life at three months in univariate and multivariable analysis. Results: Among 229 patients (mean age 64.9 years, 55% male, 29.7% black, and median initial NIHSS score 1), impaired health-related quality of life was noted in 84 (36.2%) patients at three months. In univariate analysis, patients with subcortical infarcts (56.0% vs. 39.3%, p = 0.02) and brainstem infarcts (21.4% vs. 10.3%, p = 0.02) were more likely to have impaired health-related quality of life. In multivariable analysis, patients with subcortical and/or brainstem infarcts had increased odds of impaired health-related quality of life (adjusted OR 2.54, 95% CI 1.29–5.01, p = 0.01). Conclusions: After mild ischemic stroke, subcortical and brainstem infarct locations predict impairment in health-related quality of life.

Sufficient temporal resolution is required to image the dynamics of blood flow, which may be critical for accurate diagnosis and treatment of various intracranial vascular diseases, such as arteriovenous malformations (AVMs) and aneurysms. Highly‐constrained projection reconstruction (HYPR) has recently become a technique of interest for high‐speed contrast‐enhanced magnetic resonance angiography (CE‐MRA). HYPR provides high frame rates by preferential weighting of radial projections while maintaining signal‐to‐noise ratio (SNR) by using a high SNR composite. An analysis was done to quantify the effects of HYPR on SNR, contrast‐to‐noise ratio (CNR), and temporal blur compared to the previously developed radial sliding‐window technique using standard filtered backprojection or regridding methods. Computer simulations were performed to study the effects of HYPR processing on image error and the temporal information. Additionally, in vivo imaging was done on patients with angiographically confirmed AVMs to measure the effects of alteration of various HYPR parameters on SNR as well as the fidelity of the temporal information. The images were scored by an interventional radiologist in a blinded read and were compared with X‐ray digital subtraction angiography (DSA). It was found that with the right choice of parameters, modest improvements in both SNR and dynamic information can be achieved as compared to radial sliding‐window MRA. Magn Reson Med, 2009.