Search Results (86)

Background: Interstitial myocardial fibrosis is a crucial pathological feature of many cardiovascular disorders. Myocardial fibrosis resulting in extracellular volume (ECV) expansion can be quantified via cardiac MRI (CMR) with T₁ mapping before and after minimally invasive gadolinium (Gd) contrast agent administration. However, longitudinal repetitive ECV measurements are challenging in rodents due to the prolonged scan time with cardiac and respiratory gating that is required for conventional T₁ mapping and the invasive nature of the rodent intravenous lines. Methods: To address these challenges, the objective of this study is to establish a fast, free-breathing, and gating-free ECV procedure using a minimally invasive subcutaneous catheter for in-scanner Gd administration that can allow longitudinal repetitive ECV evaluations in rodent models. This is achieved by the (1) IntraGate sequence for free-breathing, gating-free cardiac imaging; (2) minimally invasive subcutaneous in-scanner Gd administration; and (3) fast T₁ mapping with a varied flip angle (VFA) in conjunction with (4) triple jugular vein blood T₁ normalization. Additionally, full cine CMR (multi-slice short-axis, long-axis 2-chamber, and long-axis 4-chamber) was acquired during the waiting period to assess comprehensive cardiac function and strain. Results: We successfully established a minimally invasive fast ECV quantification protocol to enable longitudinal repetitive ECV quantifications in rodents. Minimally invasive subcutaneous Gd bolus administration induced a reasonable dynamic contrast enhancement (DCE) time course, reaching a steady state in ~20 min for stable T₁ quantification. The free-breathing gating-free VFA T₁ quantification scheme allows for rapid cardiac (~2.5 min) and jugular vein (49 s) T₁ quantification with no motion artifacts. The triple jugular vein T₁ acquisitions (1 pre-contrast and 2 post-contrast) immediately flanking the heart T₁ acquisitions enable accurate myocardial ECV quantification. Our data demonstrated that left-ventricular myocardial ECV quantification was highly reproducible with repeated scans, and the ECV values (0.25) are comparable to reported ranges among humans and rodents. This protocol was successfully applied to the ischemia–reperfusion injury model to detect myocardial fibrosis, which was validated by histopathology. Conclusions: We established a simple, fast, minimally invasive, and robust CMR protocol in rodents that can enable longitudinal repetitive ECV quantification for cardiovascular disease progression. It can be used to monitor disease regression with interventions. Full article

Cine (dynamic) MRI is a non-invasive MRI technique that captures moving images and can be valuable in evaluating inflammatory bowel disease (IBD). This sequence shows emerging potential in providing functional data to assess bowel motility patterns, to aid in the differentiation between predominantly inflammatory (showing reduced peristalsis) and fibrotic strictures (rigid, non-motile segments) and detecting functional obstructions in Crohn’s disease (CD). Unlike static MRI, cine MRI enables clinicians to observe peristaltic movements, aiding in disease characterization and treatment monitoring. Its non-invasive nature and lack of ionizing radiation make it especially useful for repeated assessments in CD. Studies indicate it improves diagnostic accuracy when used with conventional MRI sequences, providing a complementary, functional dimension to the comprehensive management of this chronic condition. While the functional assessment offered by cine MRI presents a significant advantage over conventional static imaging, its clinical translation is currently challenged by high technical variability. Specifically, there is a distinct lack of standardized acquisition protocols (such as field strength, sequence parameters), post-processing software, and universally validated quantitative motility metrics (such as motility index). Therefore, a primary objective of this review is not only to summarize the evolving diagnostic and monitoring applications of cine MRI but also to critically address the methodological inconsistencies and reproducibility hurdles that must be overcome before this technique can be fully integrated into clinical guidelines for precision management of CD. Full article

A novel approach to generate left ventricular (LV) pressure–volume (PV) loops from combined 4D Flow MRI and computational fluid dynamics (CFD) is presented. Pressure was calculated from person-specific three-dimensional (3D) CFD models created from LV segmentations and peak-systolic pressure from the one-dimensional 111-artery CFD model, with aortic flow from 4D Flow MRI as input. Ten healthy volunteers underwent scan–rescan MRI. Additionally, one patient without cardiovascular abnormalities underwent MRI and invasive catheter measurement for single-case comparison. Scan–rescan reproducibility was very good overall, with no significant differences in any parameters and ICCs of all parameters but minimum pressure were significant and high (0.55–0.99). Aortic flow of 3D CFD model correlated well with 4D Flow (ICC = 0.74) and stroke volume of LV segmentation (ICC = 0.90). Segmentation volume variability resulted in 12% difference in stroke work and mean external power, while aortic flow variability resulted in 10–11% difference in most parameters. Single-case comparison is promising, with only 1.8 mmHg and 0.005 mmHg/mL difference in minimum pressure and EDPVR, and <10% differences for other parameters. Noninvasive pressure–volume loops can therefore reproducibly be generated from only aortic flow, cine short axis MRI, and brachial pressure measurement. Single-case comparison shows promise, but larger validation studies are needed. Full article

Background: Myocardial scar and fibrosis predict adverse cardiac outcomes. Late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) is the reference standard for detection. However, it requires gadolinium-based contrast agents (GBCAs), which may be unsuitable for some patients. Cine balanced steady-state free precession (bSSFP) sequences are universally acquired in routine CMR. They may enable contrast-free scar detection via radiomics analysis. Aim: To systematically review the diagnostic accuracy of cine CMR radiomics for myocardial scar or fibrosis detection. The reference standard is visual or threshold-based LGE. Methods: This review followed PRISMA guidelines and was registered in PROSPERO (CRD420251121699). We searched MEDLINE, Embase, and Cochrane Library up to 8 August 2025. Eligible studies compared cine CMR radiomics with LGE-based assessment in patients with suspected or known scar/fibrosis. Quality was assessed using QUADAS-2 and Radiomics Quality Score (RQS). Results: Five retrospective studies (n = 1484) were included. Two focused on myocardial infarction, two on hypertrophic cardiomyopathy, and one on ischaemic versus dilated cardiomyopathy. Diagnostic performance was good to excellent (AUC 0.74–0.96). Methodological heterogeneity was substantial in reference standards, segmentation, preprocessing, feature selection, and modelling. Only one study used external validation. QUADAS-2 showed high bias risk in patient selection and index test domains. RQS scores were low (30–42%), indicating limited reproducibility and validation. Conclusions: Cine CMR radiomics shows promise as a non-contrast alternative for detecting myocardial scar and fibrosis. However, methodological standardisation, multicentre validation, and prospective studies are needed before clinical adoption. Full article

Pulse wave velocity (PWV) is a key marker of aortic stiffness and cardiovascular risk, yet current methods typically offer only global or regional estimates and lack the possibility to measure local variations along the thoracic aorta. This study aimed to develop and evaluate a pipeline for assessing local aortic PWV using the flow–area (QA) method (PWV_QA) by combining high-resolution 4D MRI techniques. A 3D cine balanced steady-state free precession (bSSFP) sequence was used to capture dynamic changes in aortic geometry, while 4D flow MRI measured time-resolved blood flow. The QA method was applied during the reflection-free early systolic phase. Scan–rescan reproducibility was assessed in six healthy volunteers, and feasibility was additionally explored in Marfan syndrome patients. The mean ± SD values of the Pearson correlation coefficients for per-slice maximum area, velocity, flow, and PWV_QA were 0.99 ± 0.00, 0.82 ± 0.11, 0.96 ± 0.01, and 0.20 ± 0.35, respectively. The median (Q1–Q3) average PWV_QA was 6.6 (5.4–9.4) m/s for scan 1 and 9.1 (6.7–11.3) m/s for scan 2 (p = 0.16) in healthy volunteers and 7.1 (6.9–8.0) m/s in Marfan patients. Combining 4D bSSFP and 4D flow MRI is technically feasible, but the derived PWV_QA maps show high variability, particularly in the aortic root and descending aorta, requiring further optimization. Full article

Background/Objectives: Spontaneous intracranial hypotension (SIH), caused by spinal cerebrospinal fluid (CSF) leakage, commonly presents with orthostatic headache and CSF hypovolemia. While CSF dynamics in the cerebral aqueduct are well studied, alterations in spinal CSF flow remain less defined. We aimed to quantitatively assess spinal CSF flow at C2 using phase-contrast (PC) MRI enhanced by artificial intelligence (AI) and to evaluate its utility for diagnosing SIH and predicting responses to epidural blood patch (EBP). Methods: We enrolled 31 patients with MRI-confirmed SIH and 26 age- and sex-matched healthy volunteers (HVs). All participants underwent ECG-gated cine PC-MRI at the C2 level and whole-spine MR myelography. AI-based segmentation using YOLOv4 and a pulsatility-based algorithm was used to extract quantitative CSF flow metrics. Between-group comparisons were analyzed using Mann–Whitney U tests, and receiver operating characteristic (ROC) analysis was used to evaluate diagnostic and predictive performance. Results: Compared to HVs, SIH patients showed significantly reduced CSF flow parameters across all metrics, including upward/downward mean flow, peak flow, total flow per cycle, and absolute stroke volume (all p < 0.001). ROC analysis revealed excellent diagnostic accuracy for multiple parameters, particularly downward peak flow (AUC = 0.844) and summation of peak flow (AUC = 0.841). Importantly, baseline CSF flow metrics significantly distinguished patients who required one versus multiple epidural blood patches (EBPs) (all p < 0.001). ROC analysis demonstrated that several parameters achieved near-perfect to perfect accuracy in predicting EBP success, with AUCs up to 1.0 and 100% sensitivity/specificity. Conclusions: AI-enhanced PC-MRI enables the robust, quantitative evaluation of spinal CSF dynamics in SIH. These flow metrics not only differentiate SIH patients from healthy individuals but also predict response to EBP treatment with high accuracy. Quantitative CSF flow analysis may support both diagnosis and personalized treatment planning in SIH. Full article

(1) Objective: The objective was to test the hypothesis that cine MRI-derived radiomic features can detect functional tricuspid regurgitation (FTR) in the context of pulmonary hypertension (PH). (2) Materials and methods: In total, 53 PH patients were retrospectively enrolled. Thirty-three patients had echocardiography-defined mild-to-severe FTR, while the other twenty patients had no or trivial regurgitation. For all participants, 93 radiomic features were extracted from four-chamber cine MRI using a fixed-size region of interest (ROI) located in the right atrium (RA), 0.5–1 cm above the tricuspid valve. The levels of radiomic features were averaged over the ventricular systole and compared between patients with and without FTR using t tests. In patients with FTR, radiomic features were related to hemodynamic parameters in the right heart using the Pearson correlation coefficient (r). (3) Results: There were no significant differences in demographic information, right heart catheterization (RHC) results, and most cine MRI-derived cardiac function indices between the two subject groups. Eight of ninety-three radiomic features were significantly different between PH patients with and without FTR. Radiomic features can be used to discriminate two subject groups (AUC = 0.77). In patients with FTR, multiple radiomic features are related to the pressure in the RA, right ventricle (RV), and pressure difference between RA and RV (r: 0.4 to 0.55), p values < 0.05. (4) Conclusion: Cine MRI-derived radiomic features of the cardiac blood pool differ between PH patients with and without FTR. Cine MRI shows promise as a method for assessing FTR in the context of complex cardiovascular diseases (CVDs). Full article

Background: Stereotactic body radiation therapy (SBRT) has proven effective in controlling spinal lesions with minimal toxicity, primarily due to its ability to limit spinal cord dose. Recent advances in MR-linac (MRL) technology offer superior spinal cord visualization and real-time gating, which can facilitate dose escalation in spinal tumor treatment while maintaining safety. Purpose: This study aimed to optimize motion management for spine SBRT on an MRL by analyzing patient-specific motion dynamics and evaluating the most effective registration structures. We hypothesized that baseline shifts (BLS) would improve delivery efficiency while maintaining spinal cord dose constraints. The goal was to establish displacement thresholds and assess the role of baseline shift correction adaptative planning in improving treatment delivery efficiency. Methods: Twelve patients underwent two MRI sessions on the MRL. The optimal registration structure was identified, and intrafraction motion was assessed to calculate delivery efficiency. Baseline shift (BLS) simulations were applied for five cases that showed significant motion and suboptimal delivery efficiency, and the dosimetric impact of the BLS was evaluated. The simulated BLS-based plan adaptation was implemented via a segment aperture morphing adapt-to-position workflow. Results: The most stable registration structure was the spinal canal plus three adjacent vertebrae. Cine imaging revealed average intrafraction motion (95th to 5th percentiles) of 0.8 ± 0.5 mm in the right-left (RL) direction, 0.9 ± 0.6 mm in the anterior–posterior (AP) direction, and 0.7 ± 0.5 mm in the SI direction. Simulated BLS improved delivery efficiency to >80% in all but one case, with a ±1 mm displacement threshold tolerance. While target coverage remained consistent after BLS simulation, the spinal cord dose increased by 7–60%, exceeding the 14 Gy constraint in three of the five simulated cases. Conclusions: Cine imaging and BLS can enhance delivery efficiency in spine SBRT but may increase spinal cord dose. These findings underscore the need for careful patient selection, advanced motion management, and patient-specific BLS protocols. Full article

Background/Objectives: Static image captures (SICs) are the prevailing methodology for documenting thyroid nodules (TNs) on ultrasound examinations. Ultrasound cine-loop (CL) video sequences of the thyroid enable the storage and review of the entire organ in PACS, analogous to sectional imaging modalities such as CT or MRI. Expanding on SIC, the collection of more extensive datasets is possible, with the potential to enhance diagnostic performance. However, there is an absence of reliable data concerning this process. Methods: This retrospective, tertiary care, single-center study included all patients with cytologically and histopathologically diagnosed TNs from 01/16 to 12/23. A standardized CL protocol was routinely acquired in addition to conventional SIC. The diagnostic performance of ACR and Kwak TIRADS was examined for both CL and SIC in a PACS. Advantages, challenges, and limitations of CL were analyzed. Conclusions: In total, 189 patients with 329 TNs (78% females, aged 54 ± 15 years; 76% diagnosed via surgery; 14% malignant) were included. On SIC, 58 TNs (18%) were not identified (all benign). When comparing CL with SIC, a strong correlation was observed for nearly all ultrasound features (echogenicity, composition, margin, and foci; each p < 0.001) and both TIRADSs (each p < 0.001). The diagnostic accuracy of CL was slightly superior, with maximum values of 85% for ACR and 87% for Kwak TIRADS, respectively. Rating confidence and image quality exhibited superiority on SIC (each p < 0.001). The occurrence of image artifacts was more prevalent in CL (p < 0.001). The integration of cine loops into thyroid ultrasound was found to be a seamless process, thereby enhancing the risk stratification of nodules. Image quality impairments manifested more frequently in cine loops, while static image captures demonstrated higher levels of assessment confidence. Full article

In clinical practice, left ventricle hypertrophy (LVH) continues to pose a considerable challenge, highlighting the need for more reliable diagnostic approaches. This study aims to propose an automated framework for the quantification of LVH extent and the classification of myocardial segments according to hypertrophy severity using a deep learning-based algorithm. The proposed method was validated on 133 subjects, including both healthy individuals and patients with LVH. The process starts with automatic LV segmentation using U-Net and the segmentation of the left ventricle cavity based on the American Heart Association (AHA) standards, followed by the division of each segment into three equal sub-segments. Then, an automated quantification of regional wall thickness (RWT) was performed. Finally, a convolutional neural network (CNN) was developed to classify each myocardial sub-segment according to hypertrophy severity. The proposed approach demonstrates strong performance in contour segmentation, achieving a Dice Similarity Coefficient (DSC) of 98.47% and a Hausdorff Distance (HD) of 6.345 ± 3.5 mm. For thickness quantification, it reaches a minimal mean absolute error (MAE) of 1.01 ± 1.16. Regarding segment classification, it achieves competitive performance metrics compared to state-of-the-art methods with an accuracy of 98.19%, a precision of 98.27%, a recall of 99.13%, and an F1-score of 98.7%. The obtained results confirm the high performance of the proposed method and highlight its clinical utility in accurately assessing and classifying cardiac hypertrophy. This approach provides valuable insights that can guide clinical decision-making and improve patient management strategies. Full article

Objectives: We compared changes in hepatic and cardiac iron levels, left ventricular (LV) and right ventricular (RV) dimensions and function, and bi-atrial areas, all assessed through magnetic resonance imaging (MRI), between patients with non-transfusion-dependent thalassemia (NTDT) and those with neo-transfusion-dependent thalassemia (neo-TDT) over an 18-month follow-up period. Methods: We included 32 NTDT patients (42.78 ± 12.62 years, 53.1% females) and 58 neo-TDT (>4 transfusions per year) patients (44.08 ± 14.13 years, 46.6% females), consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia project. Iron overload was quantified by T2* technique, biventricular function and atrial areas by cine images. Macroscopic myocardial fibrosis was detected by the late gadolinium enhancement technique. Results: Changes in cardiac and hepatic iron levels, in biventricular ejection fractions, in LV mass index, and bi-atrial areas were comparable between the two groups. A trend of worsening biventricular dimensions was observed in the NTDT group, while the neo-TDT group showed an improvement (decrease) in biventricular size (LV stroke volume index: p = 0.036; LV cardiac index: p = 0.031; RV end-diastolic volume index: p = 0.034; RV stroke volume index: p = 0.033). The inter-group comparison showed significant differences in the changes of biventricular end-diastolic volume indexes (LV: p = 0.011 and RV: p = 0.034) and stroke volume indexes (LV: p = 0.036 and RV: p = 0.033) and in the cardiac index (p < 0.0001). At both MRI scans, the frequency of replacement myocardial fibrosis was comparable between the two groups. Conclusions: Our 18-month longitudinal data revealed distinct patterns of cardiac remodeling in NTDT and neo-TDT patients. The progressive ventricular dilation observed in NTDT patients highlights the need for careful MRI monitoring and potential interventions to address the long-term cardiac consequences of anemia. Full article

Background/Objectives: While T₂^* mapping effectively assesses cerebral blood oxygenation, its utility for capturing cardiac phase-dependent myocardial changes in hypertrophic cardiomyopathy (HCM) is underexplored. This study investigates T₂^* dynamics in an HCM mouse model, to validate T₂^* as a clinically relevant biomarker for improved HCM diagnosis and treatment monitoring. Methods: A cardiac-specific Mybpc3 genetic mouse model, closely mirroring human HCM, was used with 12 young mice (6–11 weeks old), including both male and female wild-type (WT) and Mybpc3-KI (HCM) groups. The cardiac function was assessed using self-gated multi-slice 2D CINE imaging. To investigate myocardial T₂^* variations across the cardiac cycle, multi-gradient echo (MGE) imaging was employed. This approach used retrospective gating and continuous acquisition synchronization with pulse oximetry at 9.4 T small animal MRI. Results: Mybpc3-KI mice demonstrated left-ventricular (LV) hypertrophy compared to WT (HCM = 50.08 ± 4.68 µm/g vs. WT = 45.80 ± 20.07 µm/g, p < 0.01) and reduced ejection fraction (HCM = 38.55 ± 5.39% vs. WT= 72.53 ± 3.95%, p < 0.01). Myocardial T₂^* was significantly elevated in HCM across all cardiac phases (HCM = 12.14 ± 1.54 ms vs. WT = 7.93 ± 1.57 ms, p = 0.002). Strong correlations were observed between myocardial T₂^* and LV mass (rho = 0.88, p = 0.03). Conclusions: T₂^* was elevated in HCM with increased LV mass, highlighting the potential of T₂^* MRI as a sensitive biomarker for distinguishing healthy mice from those with HCM and revealing possible myocardial abnormalities. Full article

Various studies have been conducted to reduce the blurring caused by movement in cine magnetic resonance imaging (MRI) of the heart. This study proposed a blind deconvolution method using a total variation regularization algorithm to remove blurring in cardiac cine magnetic resonance (MR) images. The MR data were acquired using a rat cardiac cine sequence in an open format. We investigated a blind deconvolution method with a total variation regularization, incorporating a 3-dimensional point-spread function on cardiac cine MRI. The gradient of magnitude (GM) and perceptual sharpness index (PSI) were used to evaluate the usefulness of the proposed deblurring method. We confirmed that the proposed method can reduce temporal blur relatively efficiently compared with the generalized variation-based deblurring algorithm. In particular, the GM and PSI values of the cardiac cine MR image corrected using the proposed method were improved by approximately 7.59 and 4.18 times, respectively, compared with the degraded image. We achieved improved image quality by validating a blind deconvolution method using a total variation regularization algorithm on the cardiac cine MR images of small animals. Full article

Background/Objectives: Diabetes-related pancreatic changes on MRI remain unclear. Thus, we evaluated the pancreatic changes on MRI in patients with both type 1 diabetes (T1D) and type 2 diabetes (T2D) using multiparametric MRI. Methods: This prospective study involved patients with T1D or T2D who underwent upper abdominal 3-T MRI. Additionally, patients without impaired glucose metabolism were retrospectively included as a control. The imaging data included pancreatic anteroposterior (AP) diameter, pancreas-to-muscle signal intensity ratio (SIR) on fat-suppressed T1-weighted image (FS-T1WI), apparent diffusion coefficient (ADC) value, T1 value on T1 map, proton density fat fraction (PDFF), and mean secretion grade of pancreatic juice flow on cine-dynamic magnetic resonance cholangiopancreatography (MRCP). The MR measurements were compared using one-way analysis of variance and the Kruskal–Wallis test. Results: Sixty-one patients with T1D (n = 7) or T2D (n = 54) and 21 control patients were evaluated. The pancreatic AP diameters were significantly smaller in patients with T1D than in patients with T2D (p < 0.05). The average SIR on FS-T1WI was significantly lower in patients with T1D than in controls (p < 0.001). The average ADC and T1 values of the pancreas were significantly higher in patients with T1D than in patients with T2D (p < 0.01) and controls (p < 0.05). The mean secretion grade of pancreatic juice flow was significantly lower in patients with T1D than in controls (p = 0.019). The average PDFF of the pancreas was significantly higher in patients with T2D than in controls (p = 0.029). Conclusions: Patients with T1D had reduced pancreas size, increased pancreatic T1 and ADC values, and decreased pancreatic juice flow on cine-dynamic MRCP, whereas patients with T2D had increased pancreatic fat content. Full article

Background: Uterine contractility, also known as uterine peristalsis (UP), is a critical determinant of fertility, affecting sperm transport and embryo implantation. Increased uterine peristaltic activity has been associated with reduced pregnancy rates. However, data are heterogeneous and uterine contractility has not been widely translated into clinical practice. Cine-MRI, although limited by cost and heterogeneity in data reporting, has emerged as a promising tool to assess uterine dynamics and increase our knowledge of UP in physiological and pathological conditions. Objective: This systematic review and meta-analysis aimed to describe patterns of UP in physiological and pathological uterine conditions, including endometriosis and fibroids, using cine-MRI. Methods: A systematic literature search of the Medline, Embase, Cochrane and CENTRAL databases and Google Scholar was conducted up to May 2024, including studies evaluating UP by cine-MRI. Clinical studies evaluating uterine contractility were included, excluding those affected by therapeutic interventions or unrelated pathologies. This meta-analysis pooled data from studies comparing uterine contractility in patients with endometriosis. Results: In the 13 included studies (365 women), uterine contractility varied significantly according to menstrual cycle phases and pathological conditions. This meta-analysis showed that women with endometriosis had higher uterine contractility in the luteal phase (0.74; 95% CI: 0.27–1.21) but not in the periovulatory phase (SMD 0.8; 95% CI: −3.78–5.37). Conclusions: Cine-MRI is a promising diagnostic tool for the analysis of UP. Endometriosis is associated with impaired UP, which may be a cause of the decreased implantation rate and infertility in endometriosis. However, further research is needed to consolidate the effect of UP on implantation and fertility and to develop standardised and cost-effective tools to assess uterine contractility and tailor infertility treatment. Full article