T1 mapping of the liver and the spleen in patients with liver fibrosis-does normalization to the blood pool increase the predictive value?

Native hepatic T1-time as a non-invasive predictor of diastolic dysfunction and a monitoring tool for disease progression and treatment response in patients with pulmonary hypertension

AIMS

Hepatic T1-time derived from cardiac magnetic resonance imaging (cMRI) reflects venous congestion and may provide a simple alternative to invasive end-diastolic elastance (Eed) for assessment of right ventricular (RV) diastolic function. We investigated the association of native hepatic T1-time with single-beat Eed and the value of hepatic T1-time for longitudinal monitoring in pulmonary hypertension (PH).

METHODS AND RESULTS

We retrospectively enrolled 85 patients with suspected PH (59% female; 78 with PH diagnosed; 7 with PH excluded) who underwent standard right heart catheterization and cMRI within 24 h between 2015 and 2020. Hepatic T1-time showed moderate to strong correlations (rho >0.3, P ≤ 0.002) with pulmonary vascular resistance, native myocardial T1-time, Eed, RV size and function, brain natriuretic peptide (BNP) level, and 6-min walk distance, and a significant association with functional class (Kruskal-Wallis P < 0.001). Eed, myocardial T1-time, and BNP were independently linked to hepatic T1-time in multivariable regression. Hepatic T1-time > 598 ms predicted elevated Eed with 72.9% sensitivity and 82.1% specificity. Hepatic T1-time was superior to Eed in predicting clinical worsening. In 16 patients with follow-up assessments, those with decreasing hepatic T1-time (7 patients) showed significant hemodynamic improvements, whereas those with increasing hepatic T1-time (9 patients) did not. In a second retrospective cohort of 27 patients with chronic thromboembolic PH undergoing balloon pulmonary angioplasty, hepatic T1-time decreased significantly and hemodynamics improved after the procedure.

CONCLUSIONS

Hepatic T1-time predicts RV diastolic dysfunction and prognosis, and may be useful for monitoring disease progression and treatment response in PH.

The diagnostic performance of T1 mapping in the assessment of breast lesions: A preliminary study

PURPOSE

To assess T1 mapping performance in distinguishing between benign and malignant breast lesions and to explore its correlation with histopathologic features in breast cancer.

METHODS

This study prospectively enrolled 103 participants with a total of 108 lesions, including 25 benign and 83 malignant lesions. T1 mapping, diffusion-weighted imaging (DWI), and dynamic contrast-enhanced (DCE) were performed. Two radiologists independently outlined the ROIs and analyzed T1 and apparent diffusion coefficient (ADC) values for each lesion, assessing interobserver reliability with the intraclass correlation coefficient (ICC). T1 and ADC values were compared between benign and malignant lesions, across different histopathological characteristics (histological grades, estrogen, progesterone and HER2 receptors expression, Ki67, N status). Receiver operating characteristic (ROC) analysis and Pearson correlation coefficient (ρ) were performed.

RESULTS

T1 values showed statistically significant differences between benign and malignant groups (P < 0.001), with higher values in the malignant (1817.08 ms ± 126.64) compared to the benign group (1429.31 ms ± 167.66). In addition, T1 values significantly increased in the ER (-) group (P = 0.001). No significant differences were found in T1 values among HER2, Ki67, N status, and histological grades groups. Furthermore, T1 values exhibited a significant correlation (ρ) with ER (P < 0.01) and PR (P = 0.03). The AUC for T1 value in distinguishing benign from malignant lesions was 0.69 (95 % CI: 0.55 - 0.82, P = 0.005), and for evaluating ER status, it was 0.75 (95 % CI: 0.62 - 0.87, P = 0.002).

CONCLUSIONS

T1 mapping holds the potential as an imaging biomarker to assist in the discrimination of benign and malignant breast lesions and assessing the ER expression status in breast cancer.

Laterality of CT-measured hepatic extracellular volume fraction in patients with chronic thromboembolic pulmonary hypertension

PURPOSE

This study examines the hepatic extracellular volume fraction (ECV) disparity between the left and right lobes (ECV_left and ECV_right) in patients with chronic thromboembolic pulmonary hypertension (CTEPH), its association with right heart catheterization (RHC) metrics, and with intolerance to increased pulmonary hypertension (PH)-targeted medication dosages.

METHODS

We retrospectively analyzed 72 CTEPH-diagnosed patients who underwent equilibrium-phase abdominal dual-energy CT (DECT) and RHC. Hepatic ECVs, derived from DECT's iodine maps using circular regions of interest in the liver and aorta, were correlated with RHC parameters via Spearman's rank correlation and lobe differences through the Wilcoxon signed-rank test. Logistic regression assessed cases with ECV_left exceeding ECV_right by > 0.05, while receiver operating characteristic curve analysis gauged ECVs' predictive power for medication intolerance.

RESULTS

Of the 72 patients (57 females; median age 69), ECV_total (0.24, IQR 0.20-0.27) moderately correlated with RHC parameters (rs = 0.28, -0.24, 0.3 for mean pulmonary arterial pressure, cardiac index [CI], and pulmonary vascular resistance index, respectively). ECV_left significantly surpassed ECV_right (0.25 vs. 0.22, p < 0.001), with a greater ECV_left by > 0.05 indicating notably lower CI (p < 0.001). In 27 patients on PH medication, ECV_left effectively predicted medication intolerance (AUC = 0.84).

CONCLUSION

In CTEPH patients, hepatic ECV correlated with RHC metrics, where elevated left lobe ECV suggested reduced CI and potential medication intolerance.

Magnetic resonance imaging T1 mapping of the liver, pancreas and spleen in children

PURPOSE

To characterize T1 relaxation times of the pancreas, liver, and spleen in children with and without abdominal pathology.

METHODS

This retrospective study included pediatric patients (< 18-years-old). T1 mapping was performed with a Modified Look-Locker Inversion Recovery sequence. Patients were grouped based on review of imaging reports and electronic medical records. The Kruskal-Wallis test with Dunn's multiple comparison was used to compare groups.

RESULTS

220 participants were included (mean age: 11.4 ± 4.2 years (1.5 T); 10.9 ± 4.5 years (3 T)). Pancreas T1 (msec) was significantly different between subgroups at 1.5 T (p < 0.0001). Significant pairwise differences included: normal (median: 583; IQR: 561-654) vs. acute pancreatitis (731; 632-945; p = 0.0024), normal vs. chronic pancreatitis (700; 643-863; p = 0.0013), and normal vs. acute + chronic pancreatitis (1020; 897-1099; p < 0.0001). Pancreas T1 was also significantly different between subgroups at 3 T (p < 0.0001). Significant pairwise differences included: normal (779; 753-851) vs. acute pancreatitis (1087; 910-1259; p = 0.0012), and normal vs. acute + chronic pancreatitis (1226; 1025-1367; p < 0.0001). Liver T1 was significantly different between subgroups only at 3 T (p = 0.0011) with pairwise differences between normal (818, 788-819) vs. steatotic (959; 848-997; p = 0.0017) and normal vs. other liver disease (882; 831-904; p = 0.0455). Liver T1 was weakly correlated with liver fat fraction at 1.5 T (r = 0.39; 0.24-0.52; p < 0.0001) and moderately correlated at 3 T (r = 0.64; 0.49-0.76; p < 0.0001). There were no significant differences in splenic T1 relaxation times between subgroups.

CONCLUSION

Pancreas T1 relaxation times are higher at 1.5 T and 3 T in children with pancreatitis and liver T1 relaxation times are higher in children with steatotic and non-steatotic chronic liver disease at 3 T.

Utility of dual-energy CT and advanced multiparametric MRI based imaging biomarkers of pancreatic fibrosis in grading the severity of chronic pancreatitis

PURPOSE

To non-invasively quantify pancreatic fibrosis and grade severity of chronic pancreatitis (CP) on dual-energy CT (DECT) and multiparametric MRI (mpMRI).

METHODS

We included 72 patients (mean age:30years; 59 men) with suspected or confirmed CP from December 2019 to December 2021 graded as equivocal(n = 20), mild(n = 18), and moderate-marked(n = 34) using composite imaging and endoscopic ultrasound criteria. Study patients underwent multiphasic DECT and mpMRI of the abdomen. Normalized iodine concentration(NIC) and fat fraction(FF) on 6-minute delayed DECT, and T1 relaxation time(T1Rt), extracellular volume fraction(ECVf), intravoxel incoherent motion-based perfusion fraction(PF), and magnetization transfer ratio(MTR) on mpMRI of pancreas were compared. 20 renal donors(for DECT) and 20 patients with renal mass(for mpMRI) served as controls.

RESULTS

NIC of pancreas in controls and progressive grades of CP were 0.24 ± 0.05, 0.80 ± 0.18, 1.06 ± 0.23, 1.40 ± 0.36, FF were 9.28 ± 5.89, 14.19 ± 5.29, 17.31 ± 5.99, 29.32 ± 12.22, T1Rt were 590.11 ± 61.13, 801.93 ± 211.01, 1006.79 ± 352.18, 1388.01 ± 312.23ms, ECVf were 0.07 ± 0.03, 0.30 ± 0.12, 0.41 ± 0.12, 0.53 ± 0.13, PF were 0.38 ± 0.04, 0.28 ± 0.07, 0.25 ± 0.09, 0.21 ± 0.05 and MTR were 0.12 ± 0.03, 0.15 ± 0.06, 0.21 ± 0.07, 0.26 ± 0.06, respectively. There were significant differences for all quantitative parameters between controls and mild CP; for NIC, PF, and ECVf between controls and progressive CP grades (p < 0.05). Area under curve for NIC, FF, T1Rt, ECVf, PF, and MTR in differentiating controls and mild CP were 1.00, 0.86, 0.95, 1.00, 0.90 and 0.84 respectively and for NIC, FF, ECVf and PF in differentiating controls and equivocal CP were 1.00, 0.76, 0.95 and 0.92 respectively.

CONCLUSION

DECT and mpMRI were useful in quantifying pancreatic fibrosis and grading the severity of CP. NIC was the most accurate marker.

Noninvasive diagnosis of liver cirrhosis: qualitative and quantitative imaging biomarkers

A diagnosis of cirrhosis initiates a shift in the management of chronic liver disease and affects the diagnostic workflow and treatment decision of primary liver cancer. Liver biopsy remains the gold standard for cirrhosis diagnosis, but it is invasive and susceptible to sampling bias and observer variability. Various qualitative and quantitative imaging biomarkers based on ultrasound, CT and MRI have been proposed for noninvasive diagnosis of cirrhosis. Qualitative imaging features are easy to apply but have moderate diagnostic sensitivity. Elastography techniques allow quantitative assessment of liver stiffness and are highly accurate for cirrhosis diagnosis. Ultrasound elastography are widely used in clinical practice, while MR elastography has narrower availability. Although not applicable in clinical practice yet, other quantitative imaging features, including liver surface nodularity, linear and volumetric measurement, extracellular volume fraction, liver enhancement on hepatobiliary phase, and parameters derived from diffusion-weighted imaging, can provide additional information of liver morphology, perfusion, and function, thus may increase diagnosis performance. The introduction of radiomics and deep learning has further improved diagnostic accuracy while reducing subjectivity. Several imaging features may also help to assess liver function and outcomes in patients with cirrhosis. In this review, we summarize the qualitative and quantitative imaging biomarkers for noninvasive cirrhosis diagnosis, and the assessment of liver function and outcomes, and discuss the challenges and future directions in this field.

Radiomic Features at Contrast-Enhanced CT Predict Virus-Driven Liver Fibrosis: A Multi-Institutional Study

INTRODUCTION

Liver fibrosis is a major cause of morbidity and mortality among in patients with chronic hepatitis. Radiomics, particularly of the spleen, may improve diagnostic accuracy and treatment strategies. External validations are necessary to ensure reliability and generalizability.

METHODS

In this retrospective study, we developed 3 radiomics models using contrast-enhanced computed tomography scans from 167 patients with liver fibrosis (training group) between January 2020 and December 2021. Radiomic features were extracted from arterial venous, portal venous, and equilibrium phase images. Recursive feature selection random forest and the least absolute shrinkage and selection operator logistic regression were used for feature selection and dimensionality reduction. Performance was assessed by area under the curve, C-index, calibration plots, and decision curve analysis. External validation was performed on 114 patients from 2 institutions.

RESULTS

Twenty-five radiomic features were significantly associated with fibrosis stage, with 80% of the top 10 features originating from portal venous phase spleen images. The radiomics models showed good performance in the validation cohort (C-indices 0.723-0.808) and excellent calibration. Decision curve analysis indicated clinical benefits, with machine learning-based radiomics models (Random Forest score and support vector machine based radiomics score) providing more significant advantages.

DISCUSSION

Radiomic features offer significant benefits over existing serum indices for staging virus-driven liver fibrosis, underscoring the value of radiomics in enhancing diagnostic accuracy. Specifically, radiomics analysis of the spleen presents additional noninvasive options for assessing fibrosis, highlighting its potential in improving patient management and outcomes.

Post-hoc standardisation of parametric T1 maps in cardiovascular magnetic resonance imaging: a proof-of-concept

BACKGROUND

In cardiovascular magnetic resonance imaging parametric T1 mapping lacks universally valid reference values. This limits its extensive use in the clinical routine. The aim of this work was the introduction of our self-developed Magnetic Resonance Imaging Software for Standardization (MARISSA) as a post-hoc standardisation approach.

METHODS

Our standardisation approach minimises the bias of confounding parameters (CPs) on the base of regression models. 214 healthy subjects with 814 parametric T1 maps were used for training those models on the CPs: age, gender, scanner and sequence. The training dataset included both sex, eleven different scanners and eight different sequences. The regression model type and four other adjustable standardisation parameters were optimised among 240 tested settings to achieve the lowest coefficient of variation, as measure for the inter-subject variability, in the mean T1 value across the healthy test datasets (HTE, N = 40, 156 T1 maps). The HTE were then compared to 135 patients with left ventricular hypertrophy including hypertrophic cardiomyopathy (HCM, N = 112, 121 T1 maps) and amyloidosis (AMY, N = 24, 24 T1 maps) after applying the best performing standardisation pipeline (BPSP) to evaluate the diagnostic accuracy.

FINDINGS

The BPSP reduced the COV of the HTE from 12.47% to 5.81%. Sensitivity and specificity reached 95.83% / 91.67% between HTE and AMY, 71.90% / 72.44% between HTE and HCM, and 87.50% / 98.35% between HCM and AMY.

INTERPRETATION

Regarding the BPSP, MARISSA enabled the comparability of T1 maps independently of CPs while keeping the discrimination of healthy and patient groups as found in literature.

FUNDING

This study was supported by the BMBF / DZHK.

Clinical Application of Quantitative MR Imaging in Nonalcoholic Fatty Liver Disease

Viral hepatitis was previously the most common cause of chronic liver disease. However, in recent years, nonalcoholic fatty liver disease (NAFLD) cases have been increasing, especially in developed countries. NAFLD is histologically characterized by fat, fibrosis, and inflammation in the liver, eventually leading to cirrhosis and hepatocellular carcinoma. Although biopsy is the gold standard for the assessment of the liver parenchyma, quantitative evaluation methods, such as ultrasound, CT, and MRI, have been reported to have good diagnostic performances. The quantification of liver fat, fibrosis, and inflammation is expected to be clinically useful in terms of the prognosis, early intervention, and treatment response for the management of NAFLD. The aim of this review was to discuss the basics and prospects of MRI-based tissue quantifications of the liver, mainly focusing on proton density fat fraction for the quantification of fat deposition, MR elastography for the quantification of fibrosis, and multifrequency MR elastography for the evaluation of inflammation.

Quantitative MRI of diffuse liver diseases: techniques and tissue-mimicking phantoms

Quantitative magnetic resonance imaging (MRI) techniques are emerging as non-invasive alternatives to biopsy for assessment of diffuse liver diseases of iron overload, steatosis and fibrosis. For testing and validating the accuracy of these techniques, phantoms are often used as stand-ins to human tissue to mimic diffuse liver pathologies. However, currently, there is no standardization in the preparation of MRI-based liver phantoms for mimicking iron overload, steatosis, fibrosis or a combination of these pathologies as various sizes and types of materials are used to mimic the same liver disease. Liver phantoms that mimic specific MR features of diffuse liver diseases observed in vivo are important for testing and calibrating new MRI techniques and for evaluating signal models to accurately quantify these features. In this study, we review the liver morphology associated with these diffuse diseases, discuss the quantitative MR techniques for assessing these liver pathologies, and comprehensively examine published liver phantom studies and discuss their benefits and limitations.

Conventional and artificial intelligence-based computed tomography and magnetic resonance imaging quantitative techniques for non-invasive liver fibrosis staging

Chronic liver disease (CLD) ultimately develops into liver fibrosis and cirrhosis and is a major public health problem globally. The assessment of liver fibrosis is important for patients with CLD for prognostication, treatment decisions, and surveillance. Liver biopsies are traditionally performed to determine the stage of liver fibrosis. However, the risks of complications and technical limitations restrict their application to screening and sequential monitoring in clinical practice. CT and MRI are essential for evaluating cirrhosis-associated complications in patients with CLD, and several non-invasive methods based on them have been proposed. Artificial intelligence (AI) techniques have also been applied to stage liver fibrosis. This review aimed to explore the values of conventional and AI-based CT and MRI quantitative techniques for non-invasive liver fibrosis staging and summarized their diagnostic performance, advantages, and limitations.

Performance of native and gadoxetate-enhanced liver and spleen T1 mapping for noninvasive diagnosis of clinically significant portal hypertension: preliminary results

PURPOSE

In this preliminary study, our aim was to assess the utility of quantitative native-T₁ (T₁-pre), iron-corrected T₁ (cT₁) of the liver/spleen and T₁ mapping of the liver obtained during hepatobiliary phase (T₁-HBP) post-gadoxetate disodium, compared to spleen size/volume and APRI (aspartate aminotransferase-to-platelet ratio index) for noninvasive diagnosis of clinically significant portal hypertension [CSPH, defined as hepatic venous pressure gradient (HVPG) ≥ 10 mm Hg].

METHODS

Forty-nine patients (M/F: 27/22, mean age 53y) with chronic liver disease, HVPG measurement and MRI were included. Breath-held T₁ and cT₁ measurements were obtained using an inversion recovery Look-Locker sequence and a T2* corrected modified Look-Locker sequence, respectively. Liver T₁-pre (n = 49), spleen T₁ (obtained pre-contrast, n = 47), liver and spleen cT₁ (both obtained pre-contrast, n = 30), liver T₁-HBP (obtained 20 min post gadoxetate disodium injection, n = 36) and liver T₁ uptake (ΔT₁, n = 36) were measured. Spleen size/volume and APRI were also obtained. Spearman correlation coefficients were used to assess the correlation between each of liver/spleen T₁/cT₁ parameters, spleen size/volume and APRI with HVPG. ROC analysis was performed to determine the performance of measured parameters for diagnosis of CSPH.

RESULTS

There were 12/49 (24%) patients with CSPH. Liver T₁-pre (r = 0.287, p = 0.045), liver T₁-HBP (r = 0.543, p = 0.001), liver ΔT₁ (r =  - 0.437, p = 0.008), spleen T₁ (r = 0.311, p = 0.033) and APRI (r = 0.394, p = 0.005) were all significantly correlated with HVPG, while liver cT₁, spleen cT₁ and spleen size/volume were not. The highest AUCs for the diagnosis of CSPH were achieved with liver T₁-HBP, liver ΔT₁ and spleen T₁: 0.881 (95%CI 0.76-1.0, p = 0.001), 0.852 (0.72-0.98, p = 0.002) and 0.781 (0.60-0.95, p = 0.004), respectively.

CONCLUSION

Our preliminary results demonstrate the potential of liver T₁ mapping obtained during HBP post gadoxetate disodium for the diagnosis of CSPH. These results require further validation.

Native T1 mapping for differentiating the histopathologic type, grade, and stage of rectal adenocarcinoma: a pilot study

Background

Previous studies have indicated that T1 relaxation time could be utilized for the analysis of tissue characteristics. T1 mapping technology has been gradually used on research of body tumor. In this study, the application of native T1 relaxation time for differentiating the histopathologic type, grade, and stage of rectal adenocarcinoma was investigated.

Methods

One hundred and twenty patients with pathologically confirmed rectal adenocarcinoma were retrospectively evaluated. All patients underwent high-resolution anatomical magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), and T1 mapping sequences. Parameters of T1 relaxation time and apparent diffusion coefficient (ADC) were measured between the different groups. The diagnostic power was evaluated though the receiver operating characteristic (ROC) curve.

Results

The T1 and ADC values varied significantly between rectal mucinous adenocarcinoma (MC) and non-mucinous rectal adenocarcinoma (AC) ([1986.1 ± 163.3 ms] vs. [1562.3 ± 244.2 ms] and [1.38 ± 0.23 × 10⁻³mm²/s] vs. [1.03 ± 0.15 × 10⁻³mm²/s], respectively; P < 0.001). In the AC group, T1 relaxation time were significantly different between the low- and high-grade adenocarcinoma cases ([1508.7 ± 188.6 ms] vs. [1806.5 ± 317.5 ms], P < 0.001), while no differences were apparent in the ADC values ([1.03 ± 0.14 × 10⁻³mm²/s] vs. [1.04 ± 0.18 × 10⁻³mm²/s], P > 0.05). No significant differences in T1 and ADC values were identified between the different T and N stage groups for both MC and AC (all P > 0.05).

Conclusions

Native T1 relaxation time can be used to discriminate MC from AC. The T1 relaxation time was helpful for differentiating the low- and high-grade of AC.

Gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid-enhanced magnetic resonance imaging for evaluating fibrosis regression in chronic hepatitis C patients after direct-acting antiviral

BACKGROUND

Direct acting antiviral (DAA) therapy has enabled hepatitis C virus infection to become curable, while histological changes remain uncontained. Few valid non-invasive methods can be confirmed for use in surveillance. Gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) is a liver-specific magnetic resonance imaging (MRI) contrast, related to liver function in the hepatobiliary phase (HBP). Whether Gd-EOB-DTPA-enhanced MRI can be used in the diagnosis and follow up of hepatic fibrosis in patients with chronic hepatitis C (CHC) has not been investigated.

AIM

To investigate the diagnostic and follow-up values of Gd-EOB-DTPA-enhanced MRI for hepatic histology in patients with CHC.

METHODS

Patients with CHC were invited to undergo Gd-EOB-DTPA-enhanced MRI and liver biopsy before treatment, and those with paired qualified MRI and liver biopsy specimens were included. Transient elastography (TE) and blood tests were also arranged. Patients treated with DAAs who achieved 24-wk sustained virological response (SVR) underwent Gd-EOB-DTPA-enhanced MRI and liver biopsy again. The signal intensity (SI) of the liver and muscle were measured in the unenhanced phase (UEP) (SI_UEP-liver, SI_UEP-muscle) and HBP (SI_HBP-liver, SI_HBP-muscle) via MRI. The contrast enhancement index (CEI) was calculated as [(SI_HBP-liver/SI_HBP-muscle)]/[(SI_UEP-liver/SI_UEP-muscle)]. Liver stiffness measurement (LSM) was confirmed with TE. Serologic markers, aspartate aminotransferase-to-platelet ratio index (APRI) and Fibrosis-4 (FIB-4), were also calculated according to blood tests. The grade of inflammation and stage of fibrosis were evaluated with the modified histology activity index (mHAI) and Ishak fibrosis score, respectively. Fibrosis regression was defined as a ≥ 1-point decrease in the Ishak fibrosis score. The correlation between the CEI and liver pathology was evaluated. The diagnostic and follow-up values of the CEI, LSM, and serologic markers were compared.

RESULTS

Thirty-nine patients with CHC were enrolled [average age, 42.3 ± 14.4 years; 20/39 (51.3%) male]. Twenty-one enrolled patients had eligible paired Gd-EOB-DTPA-enhanced MRI and liver tissues after achieving SVR. The mHAI median significantly decreased after SVR [baseline 6.0 (4.5-13.5) vs SVR 2.0 (1.5-5.5), Z = 3.322, P = 0.017], but the median stage of fibrosis did not notably change (P > 0.05). Sixty pairs of qualified MRI and liver tissue samples were available for use to analyze the relationship between the CEI and hepatic pathology. The CEI was negatively correlated with the mHAI (r = -0.56, P < 0.001) and Ishak score (r = -0.69, P < 0.001). Further stratified analysis showed that the value of the CEI decreased with the progression of the stage of fibrosis rather than with the grade of necroinflammation. For patients with Ishak score ≥ 5, the areas under receiver operating characteristics curve of the CEI, LSM, APRI, and FIB-4 were approximately at baseline, 0.87–0.93, and after achieving SVR, 0.83–0.91. The CEI cut-off value was stable (baseline 1.58 and SVR 1.59), but those of the APRI (from 1.05 to 0.24), FIB-4 (from 1.78 to 1.28), and LSM (from 10.8 kpa to 7.1 kpa) decreased dramatically. The APRI and FIB-4 cannot be used as diagnostic means for SVR in patients with Ishak score ≥ 3 (P > 0.05). Seven patients achieved fibrosis regression after achieving SVR. In these patients, the CEI median increased (from 1.71 to 1.83, Z = -1.981, P = 0.048) and those of the APRI (from 1.71 to 1.83, Z = -2.878, P = 0.004) and LSM (from 6.6 to 4.8, Z = -2.366, P = 0.018) decreased. However, in patients without fibrosis regression, the medians of the APRI, FIB-4, and LSM also changed significantly (P < 0.05).

CONCLUSION

Gd-EOB-DTPA-enhanced MRI has good diagnostic value for staging fibrosis in patients with CHC. It can be used for fibrotic-change monitoring post SVR in patients with CHC treated with DAAs.

Noninvasive assessment of clinically significant portal hypertension using ΔT1 of the liver and spleen and ECV of the spleen on routine Gd-EOB-DTPA liver MRI

PURPOSE

To analyze the predictive value of ΔT1 of the liver and spleen as well as the extracellular volume fraction (ECV) of the spleen as noninvasive biomarkers for the determination of clinically significant portal hypertension (CSPH) on routine Gd-EOB-DTPA liver MRI.

METHOD

195 consecutive patients with known or suspected chronic liver disease from 9/2018 to 7/2019 with Gd-EOB-DTPA liver MRI and abdominal T1 mapping were retrospectively included. Based on the presence of splenomegaly with thrombocytopenia, ascites and portosystemic collaterals, the patients were divided into noCSPH (n = 113), compensated CSPH (cCSPH, ≥1 finding without ascites; n = 55) and decompensated CSPH (dCSPH, ascites ± other findings; n = 27). T1 times were measured in the liver, spleen and abdominal aorta in the unenhanced and contrast-enhanced T1 maps. Native T1 times and ΔT1 of the liver and spleen as well as ECV of the spleen were compared between groups using the Kruskal-Wallis test with Dunn's post hoc test. Furthermore, cutoff values for group differentiation were calculated using ROC analysis with Youden's index.

RESULTS

ΔT1 of the liver was significantly lower in patients with cCSPH and dCSPH (p < 0.001) compared to patients with noCSPH. In the ROC analyses for differentiation between noCSPH and CSPH (cCSPH + dCSPH), a cutoff of < 0.67 for ΔT1 of the liver (AUC = 0.79) performed better than ΔT1 (AUC = 0.69) and ECV (AUC = 0.63) of the spleen with cutoffs of > 0.29 and > 41.9, respectively.

CONCLUSION

ΔT1 of the liver and spleen in addition to ECV of the spleen allow for determination of CSPH on routine Gd-EOB-DTPA liver MRI.