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Purpose To investigate if aortic stiffening as detected with cardiac MRI is an early phenomenon in the development and progression of heart failure with preserved ejection fraction (HFpEF). Materials and Methods Both clinical and preclinical studies were performed. The clinical study was a secondary analysis of the prospective HFpEF stress trial (August 2017 through September 2019) and included 48 participants (median age, 69 years [range, 65-73 years]; 33 female, 15 male) with noncardiac dyspnea (NCD, n = 21), overt HFpEF at rest (pulmonary capillary wedge pressure [PCWP] ≥ 15 mm Hg, n = 14), and masked HFpEF at rest diagnosed during exercise stress (PCWP ≥ 25 mm Hg, n = 13) according to right heart catheterization. Additionally, all participants underwent echocardiography and cardiac MRI at rest and during exercise stress. Aortic pulse wave velocity (PWV) was calculated. The mechanistic preclinical study characterized cardiac function and structure in transgenic mice with induced arterial stiffness (Runx2-smTg mice). Statistical analyses comprised nonparametric and parametric comparisons, Spearman correlations, and logistic regression models. Results Participants with HFpEF showed increased PWV (NCD vs masked HFpEF: 7.0 m/sec [IQR: 5.0-9.5 m/sec] vs 10.0 m/sec [IQR: 8.0-13.4 m/sec], P = .005; NCD vs overt HFpEF: 7.0 m/sec [IQR: 5.0-9.5 m/sec] vs 11.0 m/sec [IQR: 7.5-12.0 m/sec], P = .01). Increased PWV correlated with higher PCWP (P = .006), left atrial and left ventricular long-axis strain (all P < .02), and N-terminal pro-brain natriuretic peptide levels (P < .001). Participants with overt HFpEF had higher levels of myocardial fibrosis, as demonstrated by increased native T1 times (1199 msec [IQR: 1169-1228 msec] vs 1234 msec [IQR: 1208-1255 msec], P = .009). Aortic stiffness was independently associated with HFpEF on multivariable analyses (odds ratio, 1.31; P = .049). Runx2-smTG mice exhibited an \"HFpEF\" phenotype compared with wild-type controls, with preserved left ventricular fractional shortening but an early and late diastolic mitral annulus velocity less than 1 (mean, 0.67 ± 0.39 [standard error of the mean] vs 1.45 ± 0.47; P = .004), increased myocardial collagen deposition (mean, 11% ± 1 vs 2% ± 1; P < .001), and increased brain natriuretic peptide levels (mean, 171 pg/mL ± 23 vs 101 pg/mL ± 10; P < .001). Conclusion This study provides translational evidence that increased arterial stiffness might be associated with development and progression of HFpEF and may facilitate its early detection. Keywords: MR Functional Imaging, MR Imaging, Animal Studies, Cardiac, Aorta, Heart ClinicalTrials.gov identifier NCT03260621 Supplemental material is available for this article. © RSNA, 2024.

Brain metastases (BMs) are the most common central nervous system (CNS) neoplasms, with an increasing incidence that is due in part to an overall increase in primary cancers, improved neuroimaging modalities leading to increased detection, better systemic therapies, and longer patient survival.
OBJECTIVE: To identify cancer patients at a higher risk of developing CNS metastases and to evaluate associated prognostic factors.
METHODS: Review of imaging referral guidelines, response criteria, interval imaging assessment, modality of choice, as well as the association of clinical, serological, and imaging findings as per various cancer societies.
RESULTS: Quantitative response assessment of target and non-target brain metastases as well as an interval imaging protocol set up based on primary histological diagnosis and therapy status are discussed as per various cancer societies and imaging programs.
CONCLUSIONS: Predictive factors in the primary tumor as well as independent variables of brain metastases like size, number, and response to therapy are necessary in management. The location of CNS metastases, symptomatic disease, as well as follow up imaging findings form a skeletal plan to prognosticate the disease, keeping in mind all the available new advanced therapy options of surgery, radiation, and immunotherapy that improve patient outcome significantly.

Introduction The prevalence and clinical significance of fetal posterior cerebral artery (FPCA) variants are studied using magnetic resonance imaging (MRI) at Saveetha Medical College. This research focuses on the fetal origin of the posterior cerebral artery (PCA), a condition where the posterior communicating artery (PComA) is larger than the P1 segment of the PCA, affecting cerebral hemodynamics and associated with various cerebrovascular pathologies. Materials and methods This retrospective analysis employed MRI records from the Department of Radio Diagnosis at Saveetha Medical College, conducted between January 2013 and December 2023. The study included patients undergoing MRI for various neurological indications, with specific imaging protocols including T1- and T2-weighted sequences, diffusion-weighted imaging, and magnetic resonance angiography (MRA). Results The study confirmed a prevalence rate of FPCA variants within the expected range of 20%-30%. MRI findings were systematically analyzed by experienced radiologists to assess the presence and characteristics of FPCA variants. The relationship between these variants and clinical symptoms was explored, revealing significant correlations that emphasize the variants\' impact on patient outcomes, particularly in the context of cerebrovascular events. Conclusion The study underlines the importance of recognizing FPCA variants due to their significant implications in neurovascular health and cerebrovascular accident (CVA) outcomes. These variants alter cerebral hemodynamics and can complicate neurosurgical and diagnostic procedures. Therefore, personalized treatment and management strategies are crucial for optimizing patient care.

OBJECTIVE: Although the Boston criteria version 2.0 facilitates the sensitivity of cerebral amyloid angiopathy (CAA) diagnosis, there are only limited data about precursor symptoms. This study aimed to determine the impact of neurological and imaging features in relation to the time of CAA diagnosis.
METHODS: Patients diagnosed with probable CAA according to the Boston criteria version 1.5, treated between 2010 and 2020 in our neurocentre, were identified through a keyword search in our medical database. Neuroimaging was assessed using Boston criteria versions 1.5 and 2.0. Medical records with primary focus on the clinical course and the occurrence of transient focal neurological episodes were prospectively evaluated.
RESULTS: Thirty-eight out of 81 patients (46.9%) exhibited transient focal neurological episodes, most often sensory (13.2%) or aphasic disorders (13.2%), or permanent deficits at a mean time interval of 31.1 months (SD ±26.3; range 1-108 months) before diagnosis of probable CAA (Boston criteria version 1.5). If using Boston criteria version 2.0, all patients receiving magnetic resonance imaging (MRI) met the criteria for probable CAA, and diagnosis could have been made on average 44 months earlier. Four patients were younger than 50 years, three of them with supporting pathology. Cognitive deficits were most common (34.6%) at the time of diagnosis.
CONCLUSIONS: Non-haemorrhagic MRI markers enhance the sensitivity of diagnosing probable CAA; however, further prospective studies are proposed to establish a minimum age for inclusion. As the neurological overture of CAA may occur several years before clinical diagnosis, early clarification by MRI including haemosensitive sequences are suggested.

This article highlights the crucial role of various imaging techniques in the diagnosis and monitoring of rheumatologic diseases. It provides an overview of the different modalities available for imaging rheumatic diseases, the disease processes they are able to demonstrate, and their utility in the monitoring response to therapy. It emphasizes the need for a multifaceted approach that combines radiography, ultrasound, MR imaging, and PET imaging to gain a comprehensive understanding of disease progression and treatment response. Standardized grading systems along with quantitative imaging techniques are playing an increasing role in monitoring disease activity and assessing response to therapy.

Purpose To investigate free-breathing thoracic bright-blood four-dimensional (4D) dynamic MRI (dMRI) to characterize aeration of parenchymal lung tissue in healthy children and patients with thoracic insufficiency syndrome (TIS). Materials and Methods All dMR images in patients with TIS were collected from July 2009 to June 2017. Standardized signal intensity (sSI) was investigated, first using a lung aeration phantom to establish feasibility and sensitivity and then in a retrospective research study of 40 healthy children (16 male, 24 female; mean age, 9.6 years ± 2.1 [SD]), 20 patients with TIS before and after surgery (11 male, nine female; mean age, 6.2 years ± 4.2), and another 10 healthy children who underwent repeated dMRI examinations (seven male, three female; mean age, 9 years ± 3.6). Individual lungs in 4D dMR images were segmented, and sSI was assessed for each lung at end expiration (EE), at end inspiration (EI), preoperatively, postoperatively, in comparison to normal lungs, and in repeated scans. Results Air content changes of approximately 6% were detectable in phantoms via sSI. sSI within phantoms significantly correlated with air occupation (Pearson correlation coefficient = -0.96 [P < .001]). For healthy children, right lung sSI was significantly lower than that of left lung sSI (at EE: 41 ± 6 vs 47 ± 6 and at EI: 39 ± 6 vs 43 ± 7, respectively; P < .001), lung sSI at EI was significantly lower than that at EE (P < .001), and left lung sSI at EE linearly decreased with age (r = -0.82). Lung sSI at EE and EI decreased after surgery for patients (although not statistically significantly, with P values of sSI before surgery vs sSI after surgery, left and right lung separately, in the range of 0.13-0.51). sSI varied within 1.6%-4.7% between repeated scans. Conclusion This study demonstrates the feasibility of detecting change in sSI in phantoms via bright-blood dMRI when air occupancy changes. The observed reduction in average lung sSI after surgery in pediatric patients with TIS may indicate postoperative improvement in parenchymal aeration. Keywords: MR Imaging, Thorax, Lung, Pediatrics, Thoracic Surgery, Lung Parenchymal Aeration, Free-breathing Dynamic MRI, MRI Intensity Standardization, Thoracic Insufficiency Syndrome Supplemental material is available for this article. © RSNA, 2024.

UNASSIGNED: The radiology report is vital for providing imaging information to guide patient treatment, and template-based reporting can potentially increase the reporting completeness. In 2014, a national reporting template for radiological staging of rectal cancer using magnetic resonance imaging (MRI) was implemented in Sweden.
UNASSIGNED: To evaluate the impact of the national reporting template by comparing and analysing differences in content and completeness in MRI reports between 2010 and 2016. Focus was to compare reporting completeness (i) between different reporting years and (ii) between three defined reporting styles.
UNASSIGNED: 493 MRI reports were gathered from 10 hospitals in four healthcare regions in Sweden, comprising 243 reports from 2010 and 250 reports from 2016. Reports were classified into three reporting styles: Expanded structured, Minimised structured, and Unstructured, and analysed using qualitative content analysis based on the national template.
UNASSIGNED: In 2010, all reports adhered to Unstructured reporting. In 2016, 44, 42, and 164 reports were conformant to Expanded structured, Minimised structured, and Unstructured reporting, respectively. A comparison between the years revealed a reporting completeness of 48% for 2010 reports and 72% for 2016 reports. Among the 2016 reporting styles, Unstructured reporting had the largest gap compared to the national template, with completeness at 64% versus 77.5% for Minimised structured reporting and 93% for Expanded structured reporting.
UNASSIGNED: Implementation of template-based reporting according to Expanded structure is key to conform to national decided evidence-based practice for radiological staging of rectal cancer.

OBJECTIVE: To develop a self-supervised learning method to retrospectively estimate T1 and T2 values from clinical weighted MRI.
METHODS: A self-supervised learning approach was constructed to estimate T1, T2, and proton density maps from conventional T1- and T2-weighted images. MR physics models were employed to regenerate the weighted images from the network outputs, and the network was optimized based on loss calculated between the synthesized and input weighted images, alongside additional constraints based on prior information. The method was evaluated on healthy volunteer data, with conventional mapping as references. The reproducibility was examined on two 3.0T scanners. Performance in tumor characterization was inspected by applying the method to a public glioblastoma dataset.
RESULTS: For T1 and T2 estimation from three weighted images (T1 MPRAGE, T1 gradient echo sequences, and T2 turbo spin echo), the deep learning method achieved global voxel-wise error ≤9% in brain parenchyma and regional error ≤12.2% in six types of brain tissues. The regional measurements obtained from two scanners showed mean differences ≤2.4% and correlation coefficients >0.98, demonstrating excellent reproducibility. In the 50 glioblastoma patients, the retrospective quantification results were in line with literature reports from prospective methods, and the T2 values were found to be higher in tumor regions, with sensitivity of 0.90 and specificity of 0.92 in a voxel-wise classification task between normal and abnormal regions.
CONCLUSIONS: The self-supervised learning method is promising for retrospective T1 and T2 quantification from clinical MR images, with the potential to improve the availability of quantitative MRI and facilitate brain tumor characterization.

Low field MRI is safer and more cost effective than the high field MRI. One of the inherent problems of low field MRI is its low signal-to-noise ratio or sensitivity. In this work, we introduce a multimodal surface coil technique for signal excitation and reception to improve the RF magnetic field (B1) efficiency and potentially improve MR sensitivity. The proposed multimodal surface coil consists of multiple identical resonators that are electromagnetically coupled to form a multimodal resonator. The field distribution of its lowest frequency mode is suitable for MR imaging applications. The prototype multimodal surface coils are built, and the performance is investigated and validated through numerical simulation, standard RF measurements and tests, and comparison with the conventional surface coil at low fields. Our results show that the B1 efficiency of the multimodal surface coil outperforms that of the conventional surface coil which is known to offer the highest B1 efficiency among all coil categories, i.e., volume coil, half-volume coil and surface coil. In addition, in low-field MRI, the required low-frequency coils often use large value capacitance to achieve the low resonant frequency which makes frequency tuning difficult. The proposed multimodal surface coil can be conveniently tuned to the required low frequency for low-field MRI with significantly reduced capacitance value, demonstrating excellent low-frequency operation capability over the conventional surface coil.