Gadoxetic acid-enhanced magnetic resonance imaging in the assessment of hepatic sinusoidal obstruction syndrome in a mouse model

BACKGROUND Neoadjuvant chemotherapy can cause hepatic sinusoidal obstruction syndrome(SOS)in patients with colorectal cancer liver metastases and increases posto-perative morbidity and mortality.AIM To evaluate T1 mapping based on gadoxetic acid-enhanced magnetic resonance imaging(MRI)for diagnosis of hepatic SOS induced by monocrotaline.METHODS Twenty-four mice were divided into control(n=10)and experimental(n=14)groups.The experimental groups were injected with monocrotaline 2 or 6 days before MRI.MRI parameters were:T1 relaxation time before enhancement;T1 relaxation time 20 minutes after enhancement(T_(1post));a reduction in T1 relaxation time(△T_(1)%);and first enhancement slope percentage of the liver parenchyma(ESP).Albumin and bilirubin score was determined.Histological results served as a reference.Liver parenchyma samples from the control and experimental groups were analyzed by western blotting,and organic anion transporter polypeptide 1(OATP1)was measured.RESULTS T_(1post),△T_(1)%,and ESP of the liver parenchyma were significantly different between two groups(all P<0.001)and significantly correlated with the total histological score of hepatic SOS(r=-0.70,0.68 and 0.79;P<0.001).△T_(1)%and ESP were positively correlated with OATP1 levels(r=0.82,0.85;P<0.001),whereas T_(1post) had a negative correlation with OATP1 levels(r=-0.83;P<0.001).INTRODUCTION Hepatic sinusoidal obstruction syndrome(SOS)is also known as hepatic veno-occlusive disease of the liver[1].The main pathological feature of hepatic SOS is damage to liver terminal vessels,and the clinical symptoms of it include ascites and abdominal pain[2].It was first proposed in 1979 as an early complication of hematopoietic stem cell transplantation[3].The prevalence ranges from 5%to 60%,and hepatic SOS is a potentially severe complication and can even lead to death in severe cases[4].Recently,systemic neoadjuvant chemotherapy became widely regarded as one of the causes hepatic SOS in the patients with advanced metastatic colorectal cancer[5,6],especially those were treated with oxaliplatin[7,8].Oxaliplatin-based preoperative chemotherapy is used for patients with colorectal liver metastases as the standard regimen[8,9],because it could improve tumor resection outcome by shrinking the metastatic sites and reducing recurrence rate[10].Nevertheless,chemotherapy-induced hepatic SOS has been associated with a higher risk of postresection morbidity[11],such as intraoperative bleeding,intraoperative transfusions,and postoperative liver failure[12].Therefore,it is important to detect and diagnose of hepatic SOS timely.Currently,the gold standard is still based on liver biopsy[13],but it is an invasive procedure and has several limitations and complications,such as hemorrhage[14].A noninvasive diagnostic modality is needed for the assessment of hepatic SOS.Some noninvasive tools have been used for diagnosis of hepatic SOS.Researchers have utilized a preoperative platelet count and aspartate aminotransferase to platelet ratio index[15].In addition,some imaging methods such as shear wave ultrasonography,computed tomography,and gadoxetic acid-enhanced magnetic resonance imaging(MRI)have been promoted as useful methods for evaluation of hepatic SOS[16-18].Recent studies with monocrotaline(MCT)-treated rats were conducted to investigate diagnosis and prediction of severity of SOS.For example,intravoxel incoherent motion diffusion-weighted imaging,non-Gaussian diffusion models,and T1 rho quantification[19,20].The MCT-induced hepatic SOS animal model was reproducible,with a detailed pathological scoring criteria[21].Gadoxetic acid is a hepatocyte-specific contrast substance,which can provide parenchymal contrast in the hepato-biliary phase.It is reported that gadoxetic acid is absorbed into the liver parenchyma via organic anion transporter polypeptide 1(OATP1)on the hepatocyte membranes[22-24].Recently,several authors have described the feasibility of gadoxetic acid-enhanced MRI for the diagnosis of oxaliplatin-induced hepatic SOS[25].They mainly diagnosed hepatic SOS based on the signal intensity of the hepatobiliary specific phase.However,there were several limitations due to the inconsistency between signal intensity of the liver parenchyma and the concentration of contrast agent for evaluation of the degree of hepatic SOS[26].Therefore,we measured T1 relaxation time on parametric mapping because it is linearly related to the concentration of the contrast agent and is not affected by other factors[27].Yang et al[28]demonstrated T1 mapping on gadoxetic acid-enhanced MRI for the assessment of oxaliplatin-induced liver injury in a C57BL/6 mouse model.However,the main pathological changes in their model were hepatocyte degeneration and fibrosis.Therefore,we aimed to explore the effectiveness of T1 mapping based on gadoxetic acid-enhanced MRI for the diagnosis of hepatic SOS in a C57BL/6 mouse model,as well as a possible relation between OATP1 Levels and MRI parameters.

Three-Tesla magnetic resonance elastography for hepatic fibrosis:Comparison with diffusion-weighted imaging and gadoxetic acid-enhanced magnetic resonance imaging

AIM: To evaluate the feasibility of 3-Tesla magnetic resonance elastography (MRE) for hepatic fibrosis and to compare that with diffusion-weighted imaging (DWI) and gadoxetic acid-enhanced magnetic resonance (MR) imaging.

Gadoxetic acid magnetic-enhanced resonance imaging in the diagnosis of cholangiocarcinoma

The use of liver magnetic resonance imaging is increasing thanks to itsmultiparametric sequences that allow a better tissue characterization, and the useof hepatobiliary contrast agents. This review aims to evaluate gadoxetic acidenhanced magnetic resonance imaging in the diagnosis and staging ofcholangiocarcinoma and its different clinical and radiological classificationsproposed in the literature. We also analyze the epidemiology, risk factors incorrelation with clinical findings and laboratory data.

Indeterminate liver lesions on gadoxetic acid-enhanced magnetic resonance imaging of the liver:Case-based radiologic-pathologic review

Different histopathological manifestations of focal liver lesions show varying common and uncommon imaging findings and some pathologies may show similar appearance despite of different histopathology.It is necessary to characterise focal liver lesions accurately as not only benign and malignant lesions are managed differently,but also certain benign lesions have differing management.These lesions are increasingly being detected due to rapid growth of use of crosssectional imaging as well as improvement in image quality and new imaging techniques.Contrast enhanced magnetic resonance imaging(MRI)is considered the gold standard technique in characterising focal liver lesions.Addition of gadoxetic acid has been shown to significantly increase diagnostic accuracy in the detection and characterization of liver abnormalities.Classic imaging characteristics of common liver lesions,including their behaviour on gadoxetic acid enhanced MRI,have been described in literature over recent years.It is important to be familiar with the typical aspects of these lesions as well as know the uncommon and overlapping imaging features to reach an accurate diagnosis.In this article,we will review the well-described characteristic imaging findings of common and rare focal liver lesions and present several challenging cases encountered in the clinical setting,namely hepatocellular adenoma,focal nodular hyperplasia,hepatic angiomyolipoma,hepatocellular carcinoma,intrahepatic cholangiocarcinoma,neuroendocrine tumours as well as a pleomorphic liposarcoma of the liver.

Diagnostic performance of abbreviated gadoxetic acid-enhanced magnetic resonance protocols with contrast-enhanced computed tomography for detection of colorectal liver metastases

BACKGROUND Although contrast-enhanced magnetic resonance imaging(MRI)using gadoxetic acid has been shown to have higher accuracy,sensitivity,and specificity for the detection and characterization of hepatic metastases compared with other modalities,the long examination time would limit the broad indication.Several abbreviated enhanced MRI(Ab-MRI)protocols without dynamic phases have been proposed to achieve equivalent diagnostic performance for the detection of colorectal liver metastases.However,an optimal protocol has not been established,and no studies have assessed the diagnostic performance of Ab-MRI combined with contrast-enhanced computed tomography(CE-CT),which is the preoperative imaging of colorectal cancer staging in clinical settings,to determine the best therapeutic strategy.AIM To compare the diagnostic performance of two kinds of Ab-MRI protocol with the standard MRI protocol and a combination of the Ab-MRI protocol and CE-CT for the detection of colorectal liver metastases.METHODS Study participants comprised 87 patients(51 males,36 females;mean age,67.2±10.8 years)who had undergone gadoxetic acid-enhanced MRI and CE-CT during the initial work-up for colorectal cancer from 2010 to 2021.Each exam was independently reviewed by two readers in three reading sessions:(1)Only single-shot fast spin echo(FSE)T2-weighted or fat-suppressed-FSE-T2-weighted,diffusion-weighted,and hepatobiliary-phase images(Ab-MRI protocol 1 or 2);(2)all acquired MRI sequences(standard protocol);and(3)a combination of an Ab-MRI protocol(1 or 2)and CE-CT.Diagnostic performance was then statistically analyzed.RESULTS A total of 380 Lesions were analyzed,including 195 metastases(51.4%).Results from the two Ab-MRI protocols were similar.The sensitivity,specificity,and positive and negative predictive values from Ab-MRI were non-inferior to those from standard MRI(P>0.05),while those from the combination of Ab-MRI protocol and CE-CT tended to be higher than those from Ab-MRI alone,although the difference was not significant(P>0.05),and were quite similar to those from standard MRI(P>0.05).CONCLUSION The diagnostic performances of two Ab-MRI protocols were non-inferior to that of the standard protocol.Combining Ab-MRI with CE-CT provided better diagnostic performance than Ab-MRI alone.

Assessment of the potential interactions between favipiravir and radiocontrast agents

BACKGROUND In cases of coronavirus disease 2019(COVID-19),favipiravir is commonly included to the therapy regimen.Drug interactions between favipiravir and other COVID-19 therapy drugs are frequently researched.However,no research on possible drug interactions between Favipiravir and radiocontrast agents,which have become almost crucial in diagnostic processes while not being part of the treatment,has been found.AIM To determine potential medication interactions between Favipiravir and radiocontrast agents.METHODS The study comprised patients who were taking Favipiravir for COVID-19 therapy and underwent a contrast-enhanced computed tomography(CT)or magnetic resonance imaging(MRI)test while taking the medicine.The computerized patient files of the cases included in the study,as well as the pharmacovigilance forms in the designated hospital,were evaluated for this purpose.RESULTS The study included the evaluation of data from 1046 patients.The study sample's mean age was 47.23±9.48 years.The mean age of cases with drug interactions was statistically significant greater than that of cases with no drug interactions(P=0.003).When evaluated with logistic regression analysis,a 1-year raises in age increases the risk of developing drug interactions by 1.63 times(P=0.023).There was no statistically significant difference in the occurrence of medication interactions between the sexes(P=0.090).Possible medication interactions were discovered in 42 cases(4%).CONCLUSION The findings of this study revealed that the most notable findings as a result of the combined use of contrast agents and favipiravir were increased creatinine and transaminase values,as well as an increase in the frequency of nausea and vomiting.The majority of drug interactions discovered were modest enough that they were not reflected in the clinic.Drug interactions become more common as people get older.

Preoperative Evaluation of Posthepatectomy Liver Failure Using MRI-Based Liver Function Indices in Child-Pugh Class A Patient

Purpose: To evaluate posthepatectomy liver failure (PHLF) using gadoxetic acid-enhanced magnetic resonance imaging (MRI) with a measure of relative liver enhancement (RLE) on hepatobiliary phase images, thereby facilitating safe liver resection. Methods: Twenty patients in Child-Pugh class A underwent tumor excision surgery and indocyanine green (ICG) clearance of future remnant liver (FRL) (ICG-Krem) values were >0.05. PHLF was evaluated using the grading system of the International Study Group of Liver Surgery (ISGLS). The RLE value was defined as the signal gain percentage between the precontrast and hepatocellular images. In the whole liver and FRL, theRLE value measured the tumor-free liver parenchyma in RLE images. We examined the correlation between indocyanine green clearance (ICG-K) and MRI-based liver function in the whole liver. Preoperative PHLF evaluation was predicted using remnant hepatocellular uptake index (rHUI), remnant RLE (rRLE), coefficient variation of Rrle [Cv(rRLE)], and ICG-Krem corrected by heterogeneous liver function(HLF-ICG-Krem). Results: HLF-ICG-Krem and rRLE values correlated with INRs after postoperative day five (r = -0.55 and 0.46, p = 0.01 and 0.04, respectively). Furthermore, HLF-ICG-Krem values ≤0.05 detected two patients with higher INRs after postoperative day five. On the other hand, neither rHUI nor Cv(rRLE) was correlated with INRs after postoperative day five (r = 0.28, and -0.03, respectively;p >0.05 for both). HLF-ICG-Krem was significantly lower with PHLF than without PHLF (p = 0.005). Conclusion: HLF-ICG-Krem is useful for evaluating PHLF more correctly.