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In recent years, ultra-high-field magnetic resonance imaging (MRI) applications have been rapidly increasing in both clinical research and practice. Indeed, 7-Tesla (7T) MRI allows improved depiction of smaller structures with high signal-to-noise ratio, and, therefore, may improve lesion visualization, diagnostic capabilities, and thus potentially affect treatment decision-making. Incremental evidence emerging from research over the past two decades has provided a promising prospect of 7T magnetic resonance angiography (MRA) in the evaluation of intracranial vasculature. The ultra-high resolution and excellent image quality of 7T MRA allow us to explore detailed morphological and hemodynamic information, detect subtle pathological changes in early stages, and provide new insights allowing for deeper understanding of pathological mechanisms of various cerebrovascular diseases. However, along with the benefits of ultra-high field strength, some challenges and concerns exist. Despite these, ongoing technical developments and clinical oriented research will facilitate the widespread clinical application of 7T MRA in the near future. In this review article, we summarize technical aspects, clinical applications, and recent advances of 7T MRA in the evaluation of intracranial vascular disease. The aim of this review is to provide a clinical perspective for the potential application of 7T MRA for the assessment of intracranial vascular disease, and to explore possible future research directions implementing this technique. [ABSTRACT FROM AUTHOR]

Background: Trans‐stenotic pressure gradient (TPG) measurement is essential for idiopathic intracranial hypertension (IIH) patients with transverse sinus (TS) stenosis. Four‐D flow MRI may provide a noninvasive imaging method for differentiation of IIH patients with different TPG. Purpose: To investigate the associations between 4D flow parameters and TPG, and to evaluate the diagnostic performance of 4D flow parameters in differentiating patients with high TPG (GroupHP) from low TPG (GroupLP). Study type: Prospective. Population: 31 IIH patients with TS stenosis (age, 38 ± 12 years; 23 females) and 5 healthy volunteers (age, 25 ± 1 years; 2 females). Field Strength/Sequence: 3T, 3D phase contrast MR venography, and gradient recalled echo 4D flow sequences. Assessment: Scan‐rescan reproducibility of 4D flow parameters were performed. The correlation between TPG and flow parameters was analyzed. The netflow and velocity difference between inflow plane, outflow plane, and the stenosis plane were calculated and compared between GroupHP and GroupLP. Statistical Tests: Pearson's correlation or Spearman's rank correlation coefficient, Independent samples t‐test or Wilcoxon rank‐sum test, Intra‐class correlation coefficient (ICC), Bland–Altman analyses, Receiver operating characteristic curves. A P value <0.05 was considered significant. Results: Significant correlations were found between TPG and netflow parameters including Favg,out‐s, Favg,in‐s, Fmax,out‐s, and Fmax,in‐s (r = 0.525–0.565). Significant differences were found in Favg,out‐s, Fmax,out‐s, Favg,in‐s, and Fmax,in‐s between GroupHP and GroupLP. Using the cut‐off value of 2.19 mL/sec, the Favg,out‐s showed good estimate performance in distinguishing GroupHP from GroupLP (AUC = 0.856). The ICC (ranged 0.905–0.948) and Bland–Altman plots indicated good scan‐rescan reproducibility. Data Conclusions: 4D flow MRI derived flow parameters showed good correlations with TPG in IIH patients with TS stenosis. Netflow difference between outflow and stenosis location at TS shows the good performance in differentiating GroupHP and GroupLP cases. Level of Evidence: 2 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Objectives: The new daily persistent headache (NDPH) is a rare primary headache disorder. However, the underlying mechanisms of NDPH remain incompletely understood. This study aims to apply seed‐based analysis to explore the functional connectivity (FC) of brainstem nuclei in patients with NDPH using resting‐state functional magnetic resonance imaging (MRI). Methods: The FC analysis from the region of interest (ROI) to whole brain voxels was used to investigate 29 patients with NDPH and 37 well‐matched healthy controls (HCs) with 3.0 Tesla MRI. The 76 nuclei in the brainstem atlas were defined as ROIs. Furthermore, we explored the correlations between FC and patients' clinical characteristics and neuropsychological evaluations. Results: Patients with NDPH exhibited reduced FC in multiple brainstem nuclei compared to HCs (including right inferior medullary reticular formation, right mesencephalic reticular formation, bilateral locus coeruleus, bilateral laterodorsal tegmental nucleus‐central gray of the rhombencephalon, median raphe, left medial parabrachial nucleus, periaqueductal gray, and bilateral ventral tegmental area‐parabrachial pigmented nucleus complex) and increased FC in periaqueductal gray. No significant correlations were found between the FC of these brain regions and clinical characteristics or neuropsychological evaluations after Bonferroni correction (p > 0.00016). Conclusions: Our results demonstrated that patients with NDPH have abnormal FC of brainstem nuclei involved in the perception and regulation of pain and emotions. [ABSTRACT FROM AUTHOR]

Background: Lenticulostriate artery (LSA) obstruction is a potential cause of subcortical infarcts. However, MRI LSA evaluation at 3T is challenging. Purpose: To investigate middle cerebral artery (MCA) plaque characteristics and LSA morphology associated with subcortical infarctions in LSA territories using 7‐T vessel wall MRI (VW‐MRI) and time‐of‐flight MR angiography (TOF‐MRA). Study Type: Prospective. Population: Sixty patients with 80 MCA atherosclerotic plaques (37 culprit and 43 non‐culprit). Field Strength/Sequence: 7‐T with 3D TOF‐MRA and T1‐weighted 3D sampling perfection with application‐optimized contrast using different flip angle evolutions (SPACE) sequences. Assessment: Plaque distribution (superior, inferior, ventral, or dorsal walls), LSA origin involvement, LSA morphology (numbers of stems, branches, and length), and plaque characteristics (normalized wall index, maximal wall thickness, plaque length, remodeling index, intraplaque hemorrhage, and plaque surface morphology (regular or irregular)) were assessed. Statistical Tests: Least absolute shrinkage and selection operator regression, generalized estimating equations regression, receiver operating characteristic curve, independent t‐test, Mann–Whitney U test, Chi‐square test, Fisher's exact test, and intra‐class coefficient. A P value <0.05 was considered statistically significant. Results: Plaque irregular surface, superior wall plaque, longer plaque length, LSA origin involvement, fewer LSA stems, and shorter total and average lengths of LSAs were significantly associated with culprit plaques. Multivariable logistic analysis confirmed that LSA origin involvement (OR, 28.51; 95% CI, 6.34–181.02) and plaque irregular surface (OR, 8.32; 95% CI, 1.41–64.73) were independent predictors in differentiating culprit from non‐culprit plaques. A combination of LSA origin involvement and plaque irregular surface (area under curve = 0.92; [95% CI, 0.86–0.98]) showed good performance in identifying culprit plaques, with sensitivity and specificity of 86.5% and 86.0%, respectively. Data Conclusion: 7‐T VW‐MRI and TOF‐MRA can demonstrate plaque involvement with LSA origins. MCA plaque characteristics derived from 7‐T VW‐MRI showed good diagnostic accuracy in determining the occurrence of subcortical infarctions. Evidence Level: 2 Technical Efficacy: Stage 3 [ABSTRACT FROM AUTHOR]