Precision and Test-Retest Repeatability of Stiffness Measurement with MR Elastography: A Multicenter Phantom Study.

Background MR elastography (MRE) has been shown to have excellent performance for noninvasive liver fibrosis staging. However, there is limited knowledge regarding the precision and test-retest repeatability of stiffness measurement with MRE in the multicenter setting. Purpose To determine the precision and test-retest repeatability of stiffness measurement with MRE across multiple centers using the same phantoms. Materials and Methods In this study, three cylindrical phantoms made of polyvinyl chloride gel mimicking different degrees of liver stiffness in humans (phantoms 1-3: soft, medium, and hard stiffness, respectively) were evaluated. Between January 2021 and January 2022, phantoms were circulated between five different centers and scanned with 10 MRE-equipped clinical 1.5-T and 3-T systems from three major vendors, using two-dimensional (2D) gradient-recalled echo (GRE) imaging and/or 2D spin-echo (SE) echo-planar imaging (EPI). Similar MRE acquisition parameters, hardware, and reconstruction algorithms were used at each center. Mean stiffness was measured by a single observer for each phantom and acquisition on a single section. Stiffness measurement precision and same-session test-retest repeatability were assessed using the coefficient of variation (CV) and the repeatability coefficient (RC), respectively. Results The mean precision represented by the CV was 5.8% (95% CI: 3.8, 7.7) for all phantoms and both sequences combined. For all phantoms, 2D GRE achieved a CV of 4.5% (95% CI: 3.3, 5.7) whereas 2D SE EPI achieved a CV of 7.8% (95% CI: 3.1, 12.6). The mean RC of stiffness measurement was 5.8% (95% CI: 3.7, 7.8) for all phantoms and both sequences combined, 4.9% (95% CI: 2.7, 7.0) for 2D GRE, and 7.0% (95% CI: 2.9, 11.2) for 2D SE EPI (all phantoms). Conclusion MRE had excellent in vitro precision and same-session test-retest repeatability in the multicenter setting when similar imaging protocols, hardware, and reconstruction algorithms were used. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Tang in this issue.

Screening for exclusion of high-risk bleeding features of esophageal varices in cirrhosis through CT and MRI.

BACKGROUND & AIM: Esophageal varices (EV) screening guidelines have evolved with improved risk stratification to avoid unnecessary esophagogastroduodenoscopy (EGD) in individuals with low bleeding risks. However, uncertainties persist in the recommendations for certain patient groups, particularly those with hepatocellular carcinoma (HCC) and/or receiving non-selective beta-blockers (NSBB) without prior endoscopy. This study assessed the efficacy of imaging in ruling out EVs and their high-risk features associated with bleeding in patients with cirrhosis and with HCC. We also evaluated the impact of NSBB on the detection of these characteristics. METHODS: A total of 119 patients undergoing EGD with CT and/or MRI within 90 days of the procedure were included. 87 patients had HCC. A new imaging grading system was developed utilizing the size of EVs and the extent of their protrusion into the esophagus lumen. The negative predictive value (NPV) of EVimaging(-) versus EVimaging (+) (grades 1-3) in ruling out the presence of EV and/or high-risk features by EGD was calculated. The predictive performance of imaging was determined by logistic regression. RESULTS: The NPV of imaging for detecting EV and high-risk features was 81 % and 92 %, respectively. Among HCC patients, the NPV for EV and high-risk features was 80 % and 64 %, respectively. Being on NSBB didn't statistically impact the imaging detection of EV. Imaging was a better predictor of high-risk EGD findings than Child-Turcotte-Pugh scores. CONCLUSIONS: Our results suggest that imaging can effectively rule out the presence of EV and high-risk features during EGD, even in patients with HCC and/or receiving NSBB.

SPONTANEOUS REGRESSION OF HEPATOCELLULAR CARCINOMA: FOCUSING IN THE ASSOCIATED RISK FACTORS.

BACKGROUND: Spontaneous regression (SR) is defined as the partial or complete disappearance of a tumor, in the absence of a specific treatment. Evidence of the SR in hepatocellular carcinoma (HCC) is rare. OBJECTIVE: The authors aimed to review all the cases of SR of HCC in two reference centers of Southern Brazil, highlighting the main characteristics. METHODS: Data of all patients with HCC were retrospectively reviewed looking for the occurrence of SR in patients from two tertiary centers in Southern Brazil, in the last five years. The diagnosis of cirrhosis was established according to clinical, laboratory and imaging data, as well as upper endoscopy or histopathological examination when necessary. The diagnosis of HCC was based on typical findings according to radiologic criteria (LIRADS) or histopathological examination. Spontaneous regression was defined as a partial or complete involution of a HCC in the absence of a specific therapy. RESULTS: From all cases of HCC in the last 5 years (n=433), there were five cases of SR. Three (60%) were men, the mean age was 62.6 (50.0-76.0) years, and the etiology was HCV in 3 (60%). Complete regression was observed in three patients (60%), one patient (20%) presented partial regression, and one (20%) relapesed and died. The time of follow-up varied between 12 and 21 months. In this presentation, it was highlighted one case of SR observed after COVID-19 infection in a patient with cirrhosis. The possible mechanisms involved in this situation were reviewed, emphasizing the most common like hypoxia and immunological. There were also one patient submitted to a surgical procedure as a possible fator involved and three patients without obvious risk factors. CONCLUSION: This phenomenon will possibly contribute to a better understanding of the pathophysiological mechanisms of HCC.

Validation of Diagnostic Thresholds for Compensated Advanced Chronic Liver Disease Using Supersonic Shear Imaging.

Background The Society of Radiologists in Ultrasound (SRU) has proposed thresholds for acoustic radiation force impulse techniques to diagnose compensated advanced chronic liver disease (cACLD). However, the diagnostic performance of these thresholds has not been extensively validated. Purpose To validate the SRU thresholds in patients with chronic liver disease who underwent supersonic shear imaging and, if suboptimal diagnostic performance is observed, to identify optimal values for diagnosing cACLD. Materials and Methods This retrospective single-center study included high-risk patients with chronic liver disease who had liver stiffness (LS) measurements and had undergone endoscopy or liver biopsy between January 2018 and December 2021. Patients were randomly allocated to test and validation sets. cACLD was defined as varices at endoscopy and/or severe fibrosis or cirrhosis at liver biopsy. The diagnostic performance of the SRU guidelines was evaluated, and optimal threshold values were identified using receiver operating characteristic (ROC) curve analysis. Results A total of 1180 patients (median age, 57 years [IQR, 50-64 years]; 761 men), of whom 544 (46%) had cACLD, were included. With the SRU recommended thresholds of less than 9 kPa and greater than 13 kPa in the test set (n = 786), the sensitivity and specificity for ruling out and ruling in cACLD were 81% (303 of 374 patients; 95% CI: 77, 85) and 92% (380 of 412 patients; 95% CI: 89, 94), respectively. In ROC curve analysis, the identified optimal threshold values were less than 7 kPa and greater than 12 kPa, showing 91% sensitivity (340 of 374 patients; 95% CI: 88, 93) for ruling out cACLD and 91% specificity (373 of 412 patients; 95% CI: 87, 93) for ruling in cACLD, respectively. In the validation set (n = 394), the optimal thresholds showed 91% sensitivity (155 of 170 patients; 95% CI: 86, 95) and 92% specificity (206 of 224 patients; 95% CI: 88, 95). Conclusion Compared with the SRU guidelines, the dual LS threshold values of less than 7 kPa and greater than 12 kPa were better for diagnosing cACLD. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Barr in this issue.

Role of radiomics in staging liver fibrosis: a meta-analysis.

BACKGROUND: Fibrosis has important pathoetiological and prognostic roles in chronic liver disease. This study evaluates the role of radiomics in staging liver fibrosis. METHOD: After literature search in electronic databases (Embase, Ovid, Science Direct, Springer, and Web of Science), studies were selected by following precise eligibility criteria. The quality of included studies was assessed, and meta-analyses were performed to achieve pooled estimates of area under receiver-operator curve (AUROC), accuracy, sensitivity, and specificity of radiomics in staging liver fibrosis compared to histopathology. RESULTS: Fifteen studies (3718 patients; age 47 years [95% confidence interval (CI): 42, 53]; 69% [95% CI: 65, 73] males) were included. AUROC values of radiomics for detecting significant fibrosis (F2-4), advanced fibrosis (F3-4), and cirrhosis (F4) were 0.91 [95%CI: 0.89, 0.94], 0.92 [95%CI: 0.90, 0.95], and 0.94 [95%CI: 0.93, 0.96] in training cohorts and 0.89 [95%CI: 0.83, 0.91], 0.89 [95%CI: 0.83, 0.94], and 0.93 [95%CI: 0.91, 0.95] in validation cohorts, respectively. For diagnosing significant fibrosis, advanced fibrosis, and cirrhosis the sensitivity of radiomics was 84.0% [95%CI: 76.1, 91.9], 86.9% [95%CI: 76.8, 97.0], and 92.7% [95%CI: 89.7, 95.7] in training cohorts, and 75.6% [95%CI: 67.7, 83.5], 80.0% [95%CI: 70.7, 89.3], and 92.0% [95%CI: 87.8, 96.1] in validation cohorts, respectively. Respective specificity was 88.6% [95% CI: 83.0, 94.2], 88.4% [95% CI: 81.9, 94.8], and 91.1% [95% CI: 86.8, 95.5] in training cohorts, and 86.8% [95% CI: 83.3, 90.3], 94.0% [95% CI: 89.5, 98.4], and 88.3% [95% CI: 84.4, 92.2] in validation cohorts. Limitations included use of several methods for feature selection and classification, less availability of studies evaluating a particular radiological modality, lack of a direct comparison between radiology and radiomics, and lack of external validation. CONCLUSION: Although radiomics offers good diagnostic accuracy in detecting liver fibrosis, its role in clinical practice is not as clear at present due to comparability and validation constraints.

Successful therapy with tenofovir disoproxil fumarate (TDF) in patients with chronic hepatitis B (CHB) does not guarantee amelioration of liver damage assessing by transient elastography. A retrospective - prospective multicenter study.

BACKGROUND: Preventing disease progression and viral suppression are the main goals of antiviral therapy in chronic hepatitis B (CHB). Liver stiffness measurement (LSM) by transient elastography is a reliable non-invasive method to assess liver fibrosis in patients with CHB. Our aim was to explore factors that may affect changes in LSMs during long term tenofovir (TDF) monotherapy in a well characterized cohort of patients with compensated CHB. METHODS: We analyzed serial LSMs in 103 adult patients with CHB who were on TDF monotherapy and had at least three LSMs over a period of 90 months. RESULTS: Twenty-five (24%) patients had advanced fibrosis at baseline. A significant decline in mean LSM between baseline and last visit (8.7 ± 6.2 kPa vs. 6.7 ± 3.3, p = 10- 3) was observed. Twenty-four (23%) patients had progression of liver fibrosis with mean increase in liver stiffness of 2.8 kPa (range: 0.2-10.2 kPa). Multivariate analysis showed that BMI ≥ 25 (OR, 0.014; 95% CI, 0.001-0.157; p = 0.001) and advanced fibrosis (OR, 5.169; 95% CI, 1.240-21.540; p = 0.024) were independently associated with a fibrosis regression of > 30% of liver stiffness compared to baseline value. CONCLUSIONS: In CHB patients TDF monotherapy resulted in liver fibrosis regression, especially in patients with advanced fibrosis. Despite the successful antiviral effect of TDF, 1 out of 4 patients had liver fibrosis progression. Obesity and advanced fibrosis at baseline were independently associated with significant liver fibrosis regression.

Multiparametric ultrasound as a new concept of assessment of liver tissue damage.

Liver disease accounts for approximately 2 million deaths per year worldwide. All chronic liver diseases (CLDs), whether of toxic, genetic, autoimmune, or infectious origin, undergo typical histological changes in the structure of the tissue. These changes may include the accumulation of extracellular matrix material, fats, triglycerides, or tissue scarring. Noninvasive methods for diagnosing CLD, such as conventional B-mode ultrasound (US), play a significant role in diagnosis. Doppler US, when coupled with B-mode US, can be helpful in evaluating the hemodynamics of hepatic vessels and detecting US findings associated with hepatic decompensation. US elastography can assess liver stiffness, serving as a surrogate marker for liver fibrosis. It is important to note that interpreting these values should not rely solely on a histological classification. Contrast-enhanced US (CEUS) provides valuable information on tissue perfusion and enables excellent differentiation between benign and malignant focal liver lesions. Clinical evaluation, the etiology of liver disease, and the patient current comorbidities all influence the interpretation of liver stiffness measurements. These measurements are most clinically relevant when interpreted as a probability of compensated advanced CLD. B-mode US offers a subjective estimation of fatty infiltration and has limited sensitivity for mild steatosis. The controlled attenuation parameter requires a dedicated device, and cutoff values are not clearly defined. Quan-titative US parameters for liver fat estimation include the attenuation coefficient, backscatter coefficient, and speed of sound. These parameters offer the advantage of providing fat quantification alongside B-mode evaluation and other US parameters. Multiparametric US (MPUS) of the liver introduces a new concept for complete noninvasive diagnosis. It encourages examiners to utilize the latest features of an US machine, including conventional B-mode, liver stiffness evaluation, fat quantification, dispersion imaging, Doppler US, and CEUS for focal liver lesion characterization. This comprehensive approach allows for diagnosis in a single examination, providing clinicians worldwide with a broader perspective and becoming a cornerstone in their diagnostic arsenal. MPUS, in the hands of skilled clinicians, becomes an invaluable predictive tool for diagnosing, staging, and monitoring CLD.

Evaluation of spleen stiffness by 2D shear wave elastography for ruling out high risk varices in patients with chronic advanced liver disease. A systematic review and meta-analysis.

OBJECTIVES: To systematically review the accuracy of spleen stiffness measurement (SSM) by 2D- Shear Wave Elastography (2D-SWE) in predicting high risk for bleeding varices (HRV) in cirrhotic patients. METHODS: PubMed, Embase, Web of Science, Medline, Cochrane, and Google Scholar databases were searched up to 31/05/2023 for all human studies using 2D-SWE to estimate SSM and endoscopy to detect HRV. Meta-analysis was performed using a generalized linear mixed model. Publication bias was evaluated using the funnel plot asymmetry test. The Area Under the Summarized Receiver Operating Characteristic curve (AUSROC) was estimated using the "mada" package. RESULTS: A total of 13 studies and 1970 patients were included. Of them, 27.8 % had HRV. The pooled sensitivity and polled specificity of SSM in detecting HRV were 90 % (95 %CI:87-92 %) and 68 % (95 %CI:58-77 %), respectively, with an AUSROC at 0.86 (95 %CI:0.82-0.90). The median cutoff value of SSM in detecting HRV was 34.2 kPa. In studies including exclusively HBV cirrhotic patients, SSM's polled sensitivity and specificity in predicting HRV was 88 % (95 %CI:82-92 %) and 73 % (95 %CI:68-78 %), respectively. The AUSROC was 0.84 (95 %CI:0.81-0.87). The number of repeated measurements per patient (<5 or ≥ 5) did not affect the method's capability. Using Aixplorer to evaluate SSM had a higher sensitivity in ruling out HRV than other 2D-SWE devices. CONCLUSIONS: Our meta-analysis supports that SSM by 2D-SWE has a good diagnostic performance for ruling out HRV in cirrhosis.

Association between nonalcoholic fatty liver disease and left ventricular diastolic dysfunction: A 7-year retrospective cohort study of 3,380 adults using serial echocardiography.

AIM: Left ventricular diastolic dysfunction (LVDD) has been observed in people with nonalcoholic fatty liver disease (NAFLD) in cross-sectional studies but the causal relationship is unclear. This study aimed to investigate the impact of NAFLD and the fibrotic progression of the disease on the development of LVDD, assessed by serial echocardiography, in a large population over a 7-year longitudinal setting. METHODS: This retrospective cohort study included the data of 3,380 subjects from a medical health check-up program. We defined subjects having NAFLD by abdominal ultrasonography and assessed significant liver fibrosis by the aspartate transaminase (AST) to platelet ratio index (APRI), the NAFLD fibrosis score (NFS), and the fibrosis-4 (FIB-4) index. LVDD was defined using serial echocardiography. A parametric Cox proportional hazards model was used. RESULTS: During 11,327 person-years of follow-up, there were 560 (16.0 %) incident cases of LVDD. After adjustment for multiple risk factors, subjects with NAFLD showed an increased adjusted hazard ratio (aHR) of 1.21 (95 % confidence interval [CI]=1.02-1.43) for incident LVDD compared to those without. The risk of LV diastolic dysfunction increased progressively with increasing degree of hepatic steatosis (P< 0.001). Compared to subjects without NAFLD, the multivariable-aHR (95 % CI) for LVDD in subjects with APRI < 0.5 and APRI ≥ 0.5 were 1.20 (1.01-1.42) and 1.36 (0.90-2.06), respectively (P= 0.036), while other fibrosis prediction models (NFS and FIB-4 index) showed insignificant results. CONCLUSIONS: This study demonstrated that NAFLD was associated with an increased risk of LVDD in a large cohort. More severe forms of hepatic steatosis and/or significant liver fibrosis may increase the risk of developing LVDD.

Prevalence and predictive features of metabolic dysfunction-associated steatotic liver disease in type 1 diabetes.

AIMS/HYPOTHESIS: The prevalence and severity of metabolic dysfunction-associated steatotic liver disease (MASLD) in type 1 diabetes remain unclear. Therefore, we investigated the prevalence and severity of MASLD in type 1 diabetes and assessed which clinical features are most important in predicting MASLD severity. METHODS: A total of 453 individuals with type 1 diabetes (41.6 ± 15.0 years, 64% female, body mass index [BMI] 25.4 ± 4.2 kg/m2, and HbA1c 55.6 ± 12 mmol/mol) underwent vibration-controlled transient elastography (VCTE), with a controlled attenuation parameter (CAP) score for steatosis (≥280.0 dB/m) and a liver stiffness measurement (LMS) for fibrosis (≥8.0 kPa). A machine learning Extra-Trees classification model was performed to assess the predictive power of the clinical features associated with type 1 diabetes with respect to steatosis and fibrosis. RESULTS: The prevalence of hepatic steatosis and fibrosis was 9.5% (95% CI, 6.8-12.2) and 3.5% (95% CI, 1.8-5.2). Higher LMS was associated with a longer duration of type 1 diabetes (median 30.5 [IQR 18.0-39.3] years vs 15.0 [IQR 6.0-27.0] years), and individuals were older, had a higher BMI (mean 27.8 ± 5.2 vs 25.3 ± 4.1 kg/m2), and a higher CAP score (mean 211.4 ± 51.7 dB/m vs 241.4 ± 75.6 dB/m). The most important predictive features of fibrosis were duration of type 1 diabetes, age, and systolic blood pressure, with a mean ± SD area under the curve of 0.73 ± 0.03. CONCLUSION: Individuals with type 1 diabetes and high blood pressure, older age, higher BMI, and longer duration of disease could be considered at high-risk for developing MASLD.

Comparison of the efficacy of the gadoxetic acid MRI-derived relative enhancement index (REI) and functional liver imaging score (FLIS) in predicting liver function: validation with Albumin-Bilirubin (ALBI) grade.

PURPOSE: This study compared the predictive performance of the relative enhancement index (REI) derived from gadoxetic acid (GA)-enhanced MRI with that of the functional liver imaging score (FLIS) in estimating liver function among patients with chronic liver disease (CLD) or liver cirrhosis (LC) by validating them with the albumin-bilirubin (ALBI) grade. MATERIALS AND METHODS: We retrospectively examined 166 patients (79 women, 87 men; 57.4 years) who were diagnosed with LC or CLD and underwent GA-enhanced MRI between August 2020 and September 2023. The enhancement ratio (ER) is calculated using the formula: ER = [hepatobiliary phase liver signal (SI HBP20)-precontrast liver signal (SI pre)]/SI pre. The REI is calculated using the formula: REI = Liver Volume (LV) × ER. FLIS was assigned from the sum of three HBP image features, each scored between 0 and 2: liver parenchymal enhancement, biliary contrast excretion, and portal vein sign. Receiver operating characteristic (ROC) curve analysis was performed to determine the optimal cutoff values of ER, REI, and FLIS in differentiating between ALBI grades. The area under the curve (AUC), accuracy, sensitivity, and specificity were calculated for REI and FLIS to distinguish the ALBI grades. Spearman's rank correlation was used to evaluate the ER, REI, and FLIS correlations between the ALBI grades. To evaluate inter-reader reliability for LV, ER, REI, and FLIS, intraclass correlation coefficient (ICC) was used. RESULTS: ROC curve analysis showed that the optimal cutoff value of REI for predicting ALBI Grade 1 was 899-905 for readers 1 and 2 and 461-477 for ALBI Grade 3, respectively. REI performed best in predicting ALBI Grade 1, achieving an accuracy range of 94%-92.2%, sensitivity of 94.9%-94.1%, and specificity of 91.7%-87.5% for readers 1 and 2, respectively. All parameters showed high accuracy in distinguishing ALBI Grade 3 from other grades. However, REI outperformed the others, showing an accuracy range of 98.8%-97.6%, sensitivity of 94.4%-94.4%, and specificity of 99.3%-98% for readers 1 and 2, respectively. REI showed the best and very strong correlation with ALBI for both readers. CONCLUSION: REI showed a very strong correlation with the ALBI grades for assessing liver function. It outperformed FLIS in predicting the ALBI grades, indicating its potential as a radiologic tool comparable to or better than FLIS in predicting liver function, especially given its dependence on liver volume.

Detection of significant liver fibrosis in Chinese psoriasis patients receiving methotrexate: a comparison between transient elastography and liver histology.

INTRODUCTION: Methotrexate (MTX) is effective for treating psoriasis and psoriatic arthritis, but its potential hepatoxicity remains a concern. Liver biopsy, the gold standard for detecting MTX-induced liver injury, is invasive and carries considerable risk. Transient elastography (TE) offers a non-invasive alternative for detecting advanced liver fibrosis. This study investigated the performance of TE in detecting MTX-induced liver fibrosis among Chinese psoriasis patients, compared with liver biopsy. METHODS: This study included adult patients with clinical psoriasis. Liver stiffness measurement using TE was performed in patients receiving MTX. Exclusion criteria were known liver cirrhosis, positive viral hepatitis carrier status, or conditions influencing TE performance. Liver biopsy was performed when liver stiffness was ≥7.1 kilopascals (kPa) or when the total cumulative dose (TCD) of MTX was ≥3.5 g. RESULTS: A total of 228 patients were screened; among 34 patients who met the inclusion criteria, nine (26.5%) had significant liver fibrosis (Roenigk grade ≥3a). The area under the receiver operating characteristic curve was 0.76 (95% confidence interval=0.59-0.93; P=0.021), indicating that TE had satisfactory performance in detecting liver fibrosis. A cut-off value of 7.1 kPa of liver stiffness yielded 100% sensitivity and 68% specificity. Liver fibrosis was not correlated with the TCD of MTX or the duration of MTX use; it was significantly correlated with obesity and diabetes status (body mass index ≥30 kg/m2, waist circumference ≥138 cm, and glycated haemoglobin level ≥7.8%). CONCLUSION: Transient elastography is reliable and superior to the TCD for detecting liver fibrosis in Chinese psoriasis patients receiving MTX. Liver biopsy should be reserved for high-risk patients or patients with liver stiffness ≥11.7 kPa on TE.

Staging liver fibrosis with various diffusion-weighted magnetic resonance imaging models.

BACKGROUND: Diffusion-weighted imaging (DWI) has been developed to stage liver fibrosis. However, its diagnostic performance is inconsistent among studies. Therefore, it is worth studying the diagnostic value of various diffusion models for liver fibrosis in one cohort. AIM: To evaluate the clinical potential of six diffusion-weighted models in liver fibrosis staging and compare their diagnostic performances. METHODS: This prospective study enrolled 59 patients suspected of liver disease and scheduled for liver biopsy and 17 healthy participants. All participants underwent multi-b value DWI. The main DWI-derived parameters included Mono-apparent diffusion coefficient (ADC) from mono-exponential DWI, intravoxel incoherent motion model-derived true diffusion coefficient (IVIM-D), diffusion kurtosis imaging-derived apparent diffusivity (DKI-MD), stretched exponential model-derived distributed diffusion coefficient (SEM-DDC), fractional order calculus (FROC) model-derived diffusion coefficient (FROC-D) and FROC model-derived microstructural quantity (FROC-µ), and continuous-time random-walk (CTRW) model-derived anomalous diffusion coefficient (CTRW-D) and CTRW model-derived temporal diffusion heterogeneity index (CTRW-α). The correlations between DWI-derived parameters and fibrosis stages and the parameters' diagnostic efficacy in detecting significant fibrosis (SF) were assessed and compared. RESULTS: CTRW-D (r = -0.356), CTRW-α (r = -0.297), DKI-MD (r = -0.297), FROC-D (r = -0.350), FROC-µ (r = -0.321), IVIM-D (r = -0.251), Mono-ADC (r = -0.362), and SEM-DDC (r = -0.263) were significantly correlated with fibrosis stages. The areas under the ROC curves (AUCs) of the combined index of the six models for distinguishing SF (0.697-0.747) were higher than each of the parameters alone (0.524-0.719). The DWI models' ability to detect SF was similar. The combined index of CTRW model parameters had the highest AUC (0.747). CONCLUSION: The DWI models were similarly valuable in distinguishing SF in patients with liver disease. The combined index of CTRW parameters had the highest AUC.

US-based Sequential Algorithm Integrating an AI Model for Advanced Liver Fibrosis Screening.

Background Noninvasive tests can be used to screen patients with chronic liver disease for advanced liver fibrosis; however, the use of single tests may not be adequate. Purpose To construct sequential clinical algorithms that include a US deep learning (DL) model and compare their ability to predict advanced liver fibrosis with that of other noninvasive tests. Materials and Methods This retrospective study included adult patients with a history of chronic liver disease or unexplained abnormal liver function test results who underwent B-mode US of the liver between January 2014 and September 2022 at three health care facilities. A US-based DL network (FIB-Net) was trained on US images to predict whether the shear-wave elastography (SWE) value was 8.7 kPa or higher, indicative of advanced fibrosis. In the internal and external test sets, a two-step algorithm (Two-step#1) using the Fibrosis-4 Index (FIB-4) followed by FIB-Net and a three-step algorithm (Three-step#1) using FIB-4 followed by FIB-Net and SWE were used to simulate screening scenarios where liver stiffness measurements were not or were available, respectively. Measures of diagnostic accuracy were calculated using liver biopsy as the reference standard and compared between FIB-4, SWE, FIB-Net, and European Association for the Study of the Liver guidelines (ie, FIB-4 followed by SWE), along with sequential algorithms. Results The training, validation, and test data sets included 3067 (median age, 42 years [IQR, 33-53 years]; 2083 male), 1599 (median age, 41 years [IQR, 33-51 years]; 1124 male), and 1228 (median age, 44 years [IQR, 33-55 years]; 741 male) patients, respectively. FIB-Net obtained a noninferior specificity with a margin of 5% (P < .001) compared with SWE (80% vs 82%). The Two-step#1 algorithm showed higher specificity and positive predictive value (PPV) than FIB-4 (specificity, 79% vs 57%; PPV, 44% vs 32%) while reducing unnecessary referrals by 42%. The Three-step#1 algorithm had higher specificity and PPV compared with European Association for the Study of the Liver guidelines (specificity, 94% vs 88%; PPV, 73% vs 64%) while reducing unnecessary referrals by 35%. Conclusion A sequential algorithm combining FIB-4 and a US DL model showed higher diagnostic accuracy and improved referral management for all-cause advanced liver fibrosis compared with FIB-4 or the DL model alone. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Ghosh in this issue.

Continuous Shear Wave Elastography for Liver Using Frame-to-Frame Equalization of Complex Amplitude.

This study addresses a crucial necessity in the field of noninvasive liver fibrosis diagnosis by introducing the concept of continuous shear wave elastography (C-SWE), utilizing an external vibration source and color Doppler imaging. However, an application of C-SWE to assess liver elasticity, a deep region within the human body, arises an issue of signal instability in the obtained data. To tackle this challenge, this work proposes a method involving the acquisition of multiple frames of datasets, which are subsequently compressed. Furthermore, the proposed frame-to-frame equalization method compensates discrepancies in the initial phase that might exist among multiple-frame datasets, thereby significantly enhancing signal stability. The experimental validation of this approach encompasses both phantom tests and in vivo experiments. In the phantom tests, the proposed technique is validated through a comparison with the established shear wave elastography (SWE) technique. The results demonstrate a remarkable agreement, with an error in shear wave velocity of less than 4.2%. Additionally, the efficacy of the proposed method is confirmed through in vivo tests. As a result, the stabilization of observed shear waves using the frame-to-frame equalization technique exhibits promising potential for accurately assessing human liver elasticity. These findings collectively underscore the viability of C-SWE as a potential diagnostic instrument for liver fibrosis.

Chronological Course and Clinical Features after Denver Peritoneovenous Shunt Placement in Decompensated Liver Cirrhosis.

BACKGROUND: Refractory ascites affects the prognosis and quality of life in patients with liver cirrhosis. Peritoneovenous shunt (PVS) is a treatment procedure of palliative interventional radiology for refractory ascites. Although it is reportedly associated with serious complications (e.g., heart failure, thrombotic disease), the clinical course of PVS has not been thoroughly evaluated. OBJECTIVES: To evaluate the relationship between chronological course and complications after PVS for refractory ascites in liver cirrhosis patients. MATERIALS AND METHODS: This was a retrospective study of 14 patients with refractory ascites associated with decompensated cirrhosis who underwent PVS placement between June 2011 and June 2023. The clinical characteristics, changes in cardiothoracic ratio (CTR), and laboratory data (i.e., brain natriuretic peptide (BNP), D-dimer, platelet) were evaluated. Follow-up CT images in eight patients were also evaluated for ascites and complications. RESULTS: No serious complication associated with the procedure occurred in any case. Transient increases in BNP and D-dimer levels, decreased platelet counts, and the worsening of CTR were observed in the 2 days after PVS; however, they were improved in 7 days in all cases except one. In the follow-up CT, the amount of ascites decreased in all patients, but one patient with a continuous increase in D-dimer 2 and 7 days after PVS had thrombotic disease (renal and splenic infarction). The mean PVS patency was 345.4 days, and the median survival after PVS placement was 474.4 days. CONCLUSIONS: PVS placement for refractory ascites is a technically feasible palliative therapy. The combined evaluation of chronological changes in BNP, D-dimer, platelet count and CTR, and follow-up CT images may be useful for the early prediction of the efficacy and complications of PVS.

Association between sleep apnea and ultrasound-defined liver fibrosis: Results from NHANES 2017 to 2020.

Liver fibrosis is a critical factor in the advancement of nonalcoholic fatty liver disease towards cirrhosis. There is limited research exploring the association between obstructive sleep apnea (OSA) and liver fibrosis among community populations. The present study aimed to assess the association between sleep apnea (SA) and liver fibrosis based on the National Health and Nutrition Examination Survey (NHANES). Data were acquired from NHANES survey cycle 2017 to 2020. We assessed liver fibrosis by the median values of liver stiffness measurement (LSM). The diagnosis of SA was based on participants' response to sleep questionnaire. Univariate and multivariate logistic regression were used to validate the association of SA and liver fibrosis. A total of 7615 participants were included in this study. The LSM level of SA group was significantly higher than non-SA group. The proportion of liver fibrosis in SA group was markedly higher than that in non-SA group (14.0% vs 7.3%, P < .001). Univariate logistic analysis showed that SA was positively associated with liver fibrosis (OR = 2.068, 95%CI = 1.715-2.494, P < .001). Further multivariate logistic analysis revealed that SA was independently associated with increased risk of liver fibrosis after adjusting for confounding factors (OR = 1.277, 95%CI = 1.003-1.625, P = .048). The current study demonstrated an independent association between self-reported SA and increased risk of ultrasound-defined liver fibrosis in community-based sample.

Evaluation and clinical significance of contrast-enhanced ultrasound on changes in liver blood flow perfusion after TIPS surgery.

To investigate the clinical value of contrast-enhanced ultrasound in the prediction of hepatic encephalopathy (HE) in patients with hepatitis B cirrhosis after intrahepatic portal-systemic shunt via jugular vein. In this retrospective study, we collected data from 75 patients with hepatitis B, cirrhosis, and portal hypertension who underwent jugular intrahepatic portosystemic shunt from February 2019 to February 2022. The diagnostic instrument used was the TOSHIBA Aplio500 color Doppler ultrasound with contrast-enhanced ultrasound capabilities. The trial group comprised 20 patients with HE within 3 months postsurgery, while the control group (CG) included 55 patients without HE within the same postoperative period. All patients underwent various examinations before and within 48 hours after surgery, including observation of liver and spleen size and stent position, as well as assessment of blood flow direction in portal and hepatic veins. Subsequently, contrast-enhanced ultrasound was employed to examine and observe perfusion changes of contrast agents in hepatic veins, hepatic arteries, and portal veins (PV). Changes in PV pressure gradient, intrahepatic, and stent blood flow perfusion (BFP) were explored in both postoperative trials and CGs. The trial group exhibited higher BFP volume, PV pressure gradient difference, and percentage decrease compared to the CG. A weak positive correlation was observed between blood flow within the liver stent and PV pressure gradient difference, as well as the percentage decrease in PV pressure gradient. The correlation coefficient between blood flowing perfusion volume within the stent and the difference in PV pressure gradient was R = 0.415 (P = .000). The correlating coefficient between BFP amount within the stent and the percentage decrease in PV pressure gradient was R = 0.261 (P = .027). The area under the receiver operating characteristic curve for stent perfusion volume, difference in PV pressure gradient, and percentage decrease in PV pressure gradient was 0.691, 0.759, and 0.742, respectively. An increase in PV pressure gradient accelerates blood flow within the stent, predisposing to HE. Changes in hepatic BFP following transjugular intrahepatic portosystemic shunt can effectively predict the occurrence of HE, demonstrating significant clinical relevance.