Keywords: Liver, Liver, Obesity, Metabolic dysfunction-associated steatohepatitis (MASH), Metabolic dysfunction-associated steatotic liver disease (MASLD), vibration-controlled transient elastography (VCTE)

Motivation: Metabolic dysfunction-associated steatohepatitis (MASH) represents a growing pandemic with obese patients at higher risk. However, obesity limits vibration-controlled transient elastography (VCTE) in frontline screening.

Goal(s): We aimed to compare the effect of body mass index (BMI) on diagnostic performance of VCTE and abbreviated MRI.

Approach: Patients (N=229) were enrolled into a prospective study with VCTE and a subset (N=59) underwent same-day abbreviated MRI.

Results: Patients with BMI > 32 had a higher failure rate of VCTE at 33%, but MRI was diagnostic in all patients. Obese patients with BMI > 32 benefit from proceeding directly to MRI for hepatic evaluation.

Impact: Obesity correlates with higher liver fibrosis in metabolic dysfunction-associated steatohepatitis (MASH), but also increases failure of vibration-controlled transient elastography (VCTE) in frontline screening. Abbreviated MRI should be considered a frontline screening modality in obese patients with BMI >32.

Keywords: Liver, Vessels, Budd-Chiari syndrome; inferior vena cava; phase contrast

Motivation: It is critical to determine whether the inferior vena cava (IVC) is occluded in Budd-Chiari syndrome (BCS) patients before interventional treatment. Magnetic resonance venography (MRV) has high sensitivity, but the specificity needs to be further improved.
 

Goal(s): This prospective study aims to compare the accuracy of IVC occlusion assessment using phase contrast MRI (PC-MRI) and MRV.
 

Approach: The Kappa coefficient test was used to evaluate the agreement, using digital subtraction angiography (DSA) as the gold standard.

Results: Intergroup agreement was excellent between PC-MR and DSA (κ=0.904), which was higher than that between MRV and DSA (κ=0.716).  

Impact: Our results suggest that PC-MR is a more accurate method for assessing IVC obstruction. However, reproducibility tests still need to be performed. In addition, the hepatic vein was not evaluated, which could be investigated in future studies.

Keywords: Liver, Tissue Characterization

Motivation: To ensure successful integration of hepatic T2 mapping into clinical workflow it is critical to establish normal reference values.

Goal(s): We defined normal ranges for hepatic T2 values using a 1.5T General Electric scanner.

Approach: Multi-echo fast-spin-echo sequences were acquired in 100 healthy volunteers and T2 values were quantified in the visible hepatic segments.

Results: Segmental and global liver T2 values exhibited a good intra- and inter-observer reproducibility. No significant regional T2 variability was detected. Global T2 values were not associated with aging but were significantly lower in males than in females.

Impact: In healthy subjects liver T2 mapping is feasible and reproducible and T2 values are influenced by gender, suggesting the need for the use of normative values differentiated by gender.

Keywords: Liver, Body

Motivation: The gold standard for clinical diagnosing varices is invasive gastroscopy.  However, there is a need for a non-invasive method to accurately assess the risk of varices in cirrhotic patients.

Goal(s): Exploring the potential of 4D Flow MRI flow quantification technique in predicting the risk of varices in patients with cirrhosis.

Approach: Fifty-three patients with liver cirrhosis and twenty-seven healthy volunteers underwent clinically relevant examinations and 4D Flow MRI imaging. The hemodynamic parameters obtained from the imaging data were analyzed.

Results: The combined index of main portal vein and splenic vein hemoflow effectively predicted the occurrence of varices in cirrhotic patients.

Impact: The use of 4D Flow MRI for predicting varices risk in liver cirrhosis patients offers a non-invasive alternative to invasive gastroscopy, improving patient comfort and reducing risks. Additionally, this study  advanced non-invasive diagnostics and personalized treatment strategies.

Keywords: Liver, Magnetization transfer

Motivation: Liver fibrosis is likely to progress into cirrhosis, which affect the patient’s quality of life. Magnetization transfer (MT) imaging  can indirectly reflect the content of structural macromolecular substances.

Goal(s): To evaluate the diagnostic accuracy of MTR imaging in staging of liver fibrosis and probe the sarcopenia in liver fibrosis stage.

Approach: 74 chronic liver diseases patients and 24 health control underwent MR examinations, MTR and 
all the patients’ MTR value, APRI and FIB-4 value were recorded.

Results: MTR -Muscle was higher than MTR-Liver in any fibrosis stages except S1. And as the liver fibrosis stages increased, the MTR-Musle decreased accordingly. 

Impact: MTR appeared may not serve as a specific marker for detecting the different liver fibrosis stages.

Keywords: Liver, Diffusion/other diffusion imaging techniques

Motivation: One of the limitations of current abdominal DWI is to obtain robust image quality, especially for SNR and image sharpness.

Goal(s): Our goal was to compare a combination of different reconstruction and averaging methods for abdominal DWI and to explore which combination is the best.

Approach: We compared five combinations of reconstruction and averaging methods and image quality was evaluated by visual evaluation and quantitative evaluation.

Results: We demonstrated the image quality of abdominal DWI could be improved by using either Ssh-DWI or CS-Complex averaging with comparable ADC values to conventional methods.

Impact: For the next step, a combination of CS reconstruction and Ssh-IRIS would be desirable for further improvement of image quality

Keywords: Liver, Contrast Agent, FLIS, chronic liver disease, Gd-EOB-DTPA, Child-Pugh score, SPSS

Motivation: To evaluate the diagnostic value of functional liver imaging score (FLIS) and spontaneous portosystemic shunt (SPSS) in patients with chronic liver disease.

Goal(s): We expect FLIS and SPSS to have a good correlation with Child-Pugh (CP) class in patients with chronic liver disease.

Approach: Analyzed the correlation between MRI parameters and CP class. ROC curves of different indexes were calculated to distinguish CP class.

Results: FLIS and three FLIS parameters showed strong to very strong correlation with CP class. The AUC of FLIS is higher than other metrics. The correlation between SPSS and the CP class of CLD patients is not significant.

Impact: The presence of SPSS can serve as an imaging biomarker for further stage of cirrhosis, and can indicate cirrhosis patients with SPSS need closer monitoring. We will keep following up the relationship between SPSS and occurrence of malignant liver events.

Keywords: Liver, Cancer

Motivation: The quality of the dynamic contrast enhanced images affects the quantification of physiological parameters.

Goal(s): We aim to quantitatively investigate the impact of reconstruction quality on the accurate estimation of physiological parameters. 

Approach: Quantitative performance of two reconstruction methods was investigated using aleatoric (i.e., inherent ambiguity) and epistemic (i.e., mismatch between high quality training data and application data) uncertainties calculated with a DL approach. 

Results: Quantitative parameter estimates for tumor sub-structures were affected by the reconstruction quality. Aleatoric and epistemic uncertainties for $$$k_{trans}$$$  and $$$v_{e}$$$ were sensitive to reconstruction quality. This metrics served as quantitative markers for assessing the quality of reconstruction methods.  

Impact: The quality of the reconstructed images can impair diagnostic accuracy of quantitative parameters. The proposed approach allows to quantify the impact of image quality on the obtained quantitative DCE parameters without the need for a ground truth information.

Keywords: Hepatobiliary, Liver, Chronic liver disease; Impaired Glucose Tolerance;T1-mapping Magnetic Resonance Imaging; Eextracellular Volume Fraction

Motivation: The mechanism of impaired glucose tolerance (IGT) in chronic liver disease (CLD) may be related to reduced insulin secretion caused by pancreatic fibrosis.

Goal(s): This study aims to evaluating the value of T1-mapping MRI in quantifying pancreatic ECV fraction for predicting IGT in CLD.

Approach: A total of 184 CLD patients were recruited in this study. Univariate and multivariate logistic regression analysis was conducted to identify independent predictors of IGT in CLD.

Results: After adjusting for age, gender, body mass index(BMI), hypertension,estimated glomerular filtration rate(eGFR), cholesterol and triglycerides, pancreatic ECV fraction was identified as an independent predictor for IGT in CLD.

Impact: The results suggest that pancreatic ECV fraction, quantified by T1-mapping MRI, may help elucidate the pathophysiological mechanisms of IGT in CLD.

Keywords: Liver, Liver

Motivation:
Research on hepatic vascular phenotypes in human populations is  currently limited. Investigating thevariations in hepatic vascular tissues across groups of  diverse ages holds significant potential for identifying innovative biomarkers  associated with aging and various diseases.

Goal(s):
To establish a comprehensive understanding of how hepatic vascular phenotypes evolve in relation to the aging process and differ between genders.

Approach:
First,  skeletonize the branches of the vessel network via a fast-marching approach.  And then Organization and Morphology phenotypes were extracted from mDixon imaging.

Results:
The study revealed 21 phenotypes exhibited a declining trend as individuals age, while 15 phenotypes showed a positive correlation with age.

Impact: These findings highlight the complex link between vascular traits and  aging, revealing subtle vascular changes over time. The study's  implications are transformative, identifying novel aging-related  biomarkers with potential applications in liver diseases.

Keywords: Liver, Liver

Motivation:  UTE-MT can non-invasively quantify the macromolecular content changes of short T2 tissues, which has the potential to assess non-alcoholic fatty liver disease (NAFLD).

Goal(s): To utilize the quantitative UTE-MT technique to assess NAFLD.

Approach: Sixteen mice (8 control mice and 8 mice with NAFLD) underwent liver scans using UTE-MT sequence on a 3T MRI scanner. 

Results: The liver UTE-MTR values of mice in the NAFLD group were significantly lower than those in the normal group. High AUC values (AUC=0.955) obtained from the ROC analysis demonstrate that the UTE-MTR could differentiate the normal and NAFLD cohorts.

Impact: The UTE-MTR can detect the macromolecular changes in the liver. Liver UTE-MTR may serve as a promising imaging biomarker to assess NAFLD.

Keywords: Liver, Liver

Motivation: MRI stands as the gold standard for diagnosing liver diseases. Ensuring widespread access to this technology is of critical importance to combat the prevalence of liver disease.

Goal(s): Our goal is to decrease the prevalence of liver disease by making the diagnostic precision of MRI broadly available.

Approach: We present a compact and open Magnetic Resonance device that employs the gold standard principles of MRI to accurately measure liver disease biomarkers.

Results: The accuracy of Proton Density Fat Fraction is shown in recent clinical studies using a point-of-care non-imaging magnetic resonance device. 

Impact: The development and implementation of a portable, cost-effective device for liver disease diagnosis can transform clinical care, improve diagnosis efficiency, and address health disparities. The technology may enhance global research and facilitate treatment monitoring and earlier intervention.

Keywords: Digestive, Challenges

Motivation: Imaging gastrointestinal obstructions and adhesions forms part of the 2024 Challenge on Unmet Clinical Needs. 

Goal(s): The goal is to investigate an analysis of tissue motion that may be able to distinguish adhering regions of tissue from normally-moving tissue. 

Approach: Time frames are non-rigidly registered giving a series of deformation fields. From these fields, a shear strain can be calculated at each pixel for each time frame. Summing over all the frames gives a single map of shear strain.  

Results: There is a visual correspondence between regions that are static, or move rigidly, and regions identified as having a low shear strain.

Impact: Shear strain is presented as a color overlay over a cine gastrointestinal motility sequence. This visualisation may aid radiological detection of adhesions and subsequently direct more appropriate surgical intervention. 

Keywords: Pancreas, Pancreas

Motivation: A clinical 3T MR system is preferably utilized due to higher image quality and better recognition of lesions and anatomy compared to 1.5T MR.

Goal(s): Our goal was to show improved abilities of 1.5T with deep learning reconstruction (DL) in evaluation of the pancreatobiliary regions comparing 3T without DL. 

Approach: In 9 patients, image qualities and information of vasculatures and soft tissues of dynamic Gd-contrast images of pancreatobiliary regions on 1.5T with DL were compared to those previously obtained on 3T without DL.

Results: 1.5T systems with DL can provide competitive information to those with 3T systems without DL for the pancreatobiliary regions.

Impact: DL reconstruction can fully utilize a 1.5T MR, providing competitive information to a 3T MR without DL for dynamic contrast studies in the pancreatobiliary regions. This can enhance patient-throughput without major socio-economic investment.

Keywords: Liver, Body

Motivation: The image quality of free-breathing sequence (4D FreeBreathing) is not stable.

Goal(s): To identify the relative factors for degraded image quality in 4D FreeBreathing.

Approach: Images using 4D FreeBreathing sequence were retrospectively obtained from 73 patients and logistic regression analysis was conducted.

Results: The presence of cirrhosis and unacceptable image quality on pre-contrast images were the relative factors for degraded image quality in 4D FreeBreathing.

Impact: It is not preferable to perform 4D FreeBreathing in patients with cirrhosis and unacceptable image quality in pre-contrast scanning. Using the information of cirrhosis and image quality at pre-contrast, we may be able to select the appropriate candidates.

Keywords: Liver, Liver, DCE

Motivation: To address the pain points in clinical abdomen DCE, including sacrifice of spatial resolution for temporal resolution, repeated breath-hold, risk of missing contrast arrival, and the need for separate T1 mapping scan.

Goal(s): To develop an all-in-one, push-button abdomen DCE technique that improves kinetic mapping.

Approach: It was developed using MR multitasking joint reconstruction and tested on volunteer and phantom.

Results: Its feasibility was proven. Its feature includes free-breathing, high spatial and temporal resolution, and embedded T1 and B1 mapping for kinetic modeling correction. 

Impact: Abdomen DCE with the proposed MR multitasking joint reconstruction approach can make clinical liver DCE more accessible, more accurate and hassle-free, allowing further researches on DCE in liver disease diagnosis.