Published online Jan 04, 2022.
https://doi.org/10.3348/kjr.2021.0407
Total Bilirubin Level as a Predictor of Suboptimal Image Quality of the Hepatobiliary Phase of Gadoxetic Acid-Enhanced MRI in Patients with Extrahepatic Bile Duct Cancer
Abstract
Objective
This study aimed to determine a factor for predicting suboptimal image quality of the hepatobiliary phase (HBP) of gadoxetic acid-enhanced MRI in patients with extrahepatic bile duct (EHD) cancer before MRI examination.
Materials and Methods
We retrospectively evaluated 259 patients (mean age ± standard deviation: 68.0 ± 8.3 years; 162 male and 97 female) with EHD cancer who underwent gadoxetic acid-enhanced MRI between 2011 and 2017. Patients were divided into a primary analysis set (n = 184) and a validation set (n = 75) based on the diagnosis date of January 2014. Two reviewers assigned the functional liver imaging score (FLIS) to reflect the HBP image quality. The FLIS consists of the sum of three HBP features, each scored on a 0–2 scale: liver parenchymal enhancement, biliary excretion, and signal intensity of the portal vein. Patients were classified into low-FLIS (0–3) or high-FLIS (4–6) groups. Multivariable analysis was performed to determine a predictor of low FLIS using serum biochemical and imaging parameters of cholestasis severity. The optimal cutoff value for predicting low FLIS was obtained using receiver operating characteristic analysis, and validation was performed.
Results
Of the 259 patients, 140 (54.0%) and 119 (46.0%) were classified into the low-FLIS and high-FLIS groups, respectively. In the primary analysis set, total bilirubin was an independent factor associated with low FLIS (adjusted odds ratio per 1-mg/dL increase, 1.62; 95% confidence interval [CI], 1.32–1.98). The optimal cutoff value of total bilirubin for predicting low FLIS was 2.1 mg/dL with a sensitivity of 95.1% (95% CI: 88.9–98.4) and a specificity of 89.0% (95% CI: 80.2–94.9). In the validation set, the total bilirubin cutoff showed a sensitivity of 92.1% (95% CI: 78.6–98.3) and a specificity of 83.8% (95% CI: 68.0–93.8).
Conclusion
Serum total bilirubin before acquisition of gadoxetic acid-enhanced MRI may help predict suboptimal HBP image quality in patients with EHD cancer.
INTRODUCTION
Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA, gadoxetic acid; Eovist or Primovist; Bayer HealthCare) provides excellent lesion-to-liver contrast during the hepatobiliary phase (HBP). This is because approximately 50% of Gd-EOB-DTPA is taken up into the functional hepatocytes, and intense hepatic parenchymal enhancement is obtained 20 minutes after contrast administration [1, 2]. In patients with biliary obstructions such as extrahepatic bile duct (EHD) cancer, however, the hepatocyte uptake of Gd-EOB-DTPA and its biliary excretion can be reduced, because Gd-EOB-DTPA uptake is mediated by the same transporter responsible for bilirubin transport [3].
CT and MRI with MR cholangiopancreatography (MRCP) are widely used for the preoperative staging of EHD cancer. There have been only a few studies on the applications of gadoxetic acid-enhanced MRI for EHD cancer [4, 5], and no consensus has been reached on which MRI contrast agent can be used to evaluate EHD cancer. Despite several drawbacks such as transient motion artifacts [6] and weak vascular enhancement caused by lower amounts of Gd-EOB-DTPA [7], the reason for implementing gadoxetic acid-enhanced MRI in patients with EHD cancer may be the high sensitivity of the HBP images for the detection of focal liver lesions, particularly sub-centimeter lesions [8, 9]. A previous study reported the usefulness of gadoxetic acid-enhanced MRI for distinguishing hepatic micro-abscesses due to biliary obstruction from metastases [10]. Because inflammatory lesions appear smaller on unenhanced T1-weighted images than on HBP images, a significant size discrepancy suggests a micro-abscess rather than a metastasis [10]. Therefore, it is important to obtain adequate hepatic parenchymal enhancement on HBP images in patients with EHD cancer.
To our knowledge, only a few studies have evaluated the relationship between liver function parameters and the HBP image quality of gadoxetic acid-enhanced MRI [3, 11, 12]. These studies included patients with various diseases, including chronic liver disease or pancreaticobiliary cancer, and were evaluated without quantitative or simple parameters reflecting the HBP image quality. The functional liver imaging score (FLIS) is a semi-quantitative scoring system that reflects the HBP image quality because it is derived from the three HBP features of gadoxetic acid-enhanced MRI [13, 14]. Predicting low FLIS before MRI examination may help in selecting the optimal MR contrast agent. Therefore, the purpose of this study was to determine the factors associated with suboptimal HBP image quality among the serum biochemical and imaging parameters of biliary obstruction, using the FLIS from the HBP features of gadoxetic acid-enhanced MRI in patients with EHD cancer.
MATERIALS AND METHODS
This retrospective study was approved by the Institutional Review Board of Samsung Medical Center (IRB No. SMC 2020-12-062), and the requirement for informed consent was waived.
Patients
A total of 1864 consecutive patients who had pathologically confirmed EHD cancer by surgery or biopsy between January 2011 and September 2017 were identified through a search of our institution’s registry. In accordance with the following criteria, 290 patients were included: 1) patients with distal common bile duct cancer or Bismuth classification I perihilar cancer, 2) patients who underwent gadoxetic acid-enhanced MRI obtained within three months before surgery or biopsy, 3) available preoperative laboratory results within two days of the MRI, and 4) contrast-enhanced CT obtained within 2 weeks before the MRI. Thirty-one patients were excluded according to the following criteria: 1) ten patients with markedly degraded MRI image quality due to artifacts, and 21 patients without follow-up CT/MRI for at least 6 months. We measured the diameter of the dilated upstream common duct to determine its role as an imaging predictor; therefore, among perihilar cancers, only Bismuth classification I cancers were included. Finally, 259 patients were included in the study. Patients were divided into two groups based on the date of EHD cancer diagnosis on January 1, 2014, and patients after the date were allocated into the primary analysis set and those before the date were allocated into the validation set (Fig. 1).
Fig. 1
Flow chart of our study.
*Among perihilar cancers, only Bismuth type I was included, in which the diameter of the dilated upstream common duct could be measured. FLIS = functional liver imaging score
CT and MRI Acquisition
CT scans were performed using one of the following multidetector CT scanners: Somatom Definition Flash 128 (Siemens Healthineers), Toshiba Aquilion 64 detector (Toshiba Medical Systems), and LightSpeed VCT 64 or Discovery CT 750 (GE Healthcare). MRI was performed using a 3T MR system (Achieva 3T, Philips Healthcare). MRI included unenhanced T1- and T2-weighted imaging, diffusion-weighted imaging, and gadoxetic acid-enhanced imaging with arterial, portal, transitional, and hepatobiliary phases. The details are provided in Supplementary Methods 1 and Supplementary Table 1.
Imaging Analysis
Two abdominal radiologists (with 12 and 11 years of experience in abdominal imaging, respectively), blinded to the detailed clinical and laboratory data, independently evaluated the CT and MR images in random order. Imaging analysis was performed using a picture archiving and communication system (Centricity; GE Healthcare) with adjustment of the optimal window width and level.
The following imaging parameters were evaluated on CT: 1) location of EHD cancer—perihilar or distal bile duct cancer based on the insertion site of the cystic duct [15]; 2) tumor morphology—intraductal-growing or periductal-infiltrating type [15]; 3) common duct diameter (mm), the largest diameter of the dilated upstream common duct measured on contrast-enhanced coronal image, 4) presence of biliary stent, and 5) presence of ascites.
The three FLIS parameters and the FLIS (the sum of three parameters, ranging from 0 to 6 points) were scored on the HBP image: 1) liver parenchymal enhancement quality score, a score of 0, 1, or 2 was assigned if the liver was hypo-, iso-, or hyperintense, respectively, to the right kidney, 2) biliary contrast excretion quality score—a score of 0, 1, or 2 was assigned if the liver was hypo-, iso-, or hyperintense, respectively, to the right duct, 3) portal contrast excretion quality score—a score of 0, 1, or 2 was assigned if the portal vein was hyper-, iso-, or hypointense, respectively, to the liver parenchyma (Supplementary Table 2) [13, 14]. The subjective assessment of the HBP image quality using a 4-point grading scale as uninterpretable, poor (below average), fair (average), or good, and the 4-point grading scale was simply divided into acceptable (fair or good) or suboptimal (poor or uninterpretable) image qualities.
If a patient was considered to have at least one focal liver lesion requiring a differential diagnosis between microabscesses and metastasis, the reviewers scored the possibility of metastasis by assigning the following confidence level: 1, definitely a micro-abscess; 2, probably a micro-abscess; 3, probably a metastasis; and 4, definitely a metastasis. The known imaging criteria were presented to the reviewers [10, 16, 17], but the final decision was made based on the subjective judgment of each reviewer. Details are provided in Supplementary Methods 2. If multiple lesions were present, the largest lesion was selected. The maximal diameter of the target lesion was measured in the axial plane during any phase. The conspicuity of the target lesion in the HBP image was evaluated as poor (poor lesion conspicuity, defined as a lesion that could not be depicted).
Clinical Data and Serum Biochemical Parameter Analyses
Age, sex, etiology of liver disease, and body mass index were assessed as baseline clinical information. For the serum biochemical parameters, the serum levels of total bilirubin, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), γ-glutamyltransferase (GGT), albumin, platelet count, prothrombin time, and creatinine obtained within two days before the MRI examination were recorded.
Final Diagnosis of Focal Liver Lesions
Final diagnoses for focal liver lesions were confirmed using pathologic results from biopsy (three metastases), an increased size, and hypermetabolism on 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT (two metastases) or follow-up CT and/or MRI (six metastases and 34 abscesses). If the size or number of the focal liver lesions increased in the follow-up images and hypermetabolism was noted on 18F-FDG PET/CT, we diagnosed it as metastasis [18, 19]. If there was evidence of infection/inflammation in clinical and laboratory findings, and the lesion decreased in follow-up images, it was diagnosed as a micro-abscess [20, 21].
Statistical Analyses
To evaluate the interobserver agreement in image interpretation, the κ values or weighted κ values were calculated. The consensus results of the two reviewers were used to analyze HBP image quality. All patients were classified into the low-FLIS (FLIS 0–3) or high-FLIS (FLIS 4–6) groups [13, 14]. Comparisons were made using the chi-square test or Fisher’s exact test for categorical variables and Student’s t test or the Mann–Whitney U test for continuous variables. Univariable and multivariable logistic regression analyses were used to identify factors associated with the low-FLIS group. For multivariable analysis, variables with p values < 0.05, in the univariable analyses, were included in the final model. Subgroup analyses in patients with or without biliary stents were also performed. The correlations between FLIS and quantitative parameters were evaluated using Spearman or Pearson correlation coefficients. Receiver operating characteristic curve analysis was used to estimate the optimal cutoff value of the serum biochemical parameters for predicting low FLIS according to the Youden index. To validate the optimal cutoff of the serum biochemical parameters, the performance for predicting low FLIS was evaluated in the validation set. Furthermore, the performance for distinguishing hepatic metastasis from abscess was calculated for each reviewer, considering each reviewer’s confidence scores of 3 or 4 as test-positive for metastasis. Comparison of the diagnostic performance for metastasis between the FLIS groups was performed using Fisher’s exact test. Statistical analyses were performed using R software version 3.3.2 (The R Foundation for Statistical Computing) and SPSS version 25 (IBM Corp.). Statistical significance was set at p < 0.05.
RESULTS
Characteristics of the Study Groups
The baseline characteristics of all 259 patients (mean age, 68.0 ± 8.3 years; range, 43–90 years; 162 male and 97 female) are summarized in Table 1. One hundred-forty patients (54.1%) were classified into the low-FLIS group and 119 (45.9%) into the high-FLIS group. Except for the etiology of liver disease and common duct diameter, there were no significant differences between the primary and validation sets.
Table 1
Characteristics of Study Population
Table 2 shows the comparison of the clinical, imaging, and biochemical parameters between the FLIS groups in the primary analysis set. Except for the common duct diameter, there were no significant differences in clinical data and imaging findings between the two groups. The common duct diameter was larger in the low-FLIS group than in the high-FLIS group (15 mm vs. 13 mm, p < 0.001). The low-FLIS group showed higher serum levels of total bilirubin, AST, ALT, ALP, and GGT, and low level of albumin than the high-FLIS group (p < 0.001). In the low-FLIS group, 97.1% showed no biliary excretion (biliary contrast excretion quality score of 0), whereas 63.7%–79.4% showed liver parenchymal enhancement equal or higher to that of the kidney and portal vein (liver parenchymal enhancement quality score of 1 and portal vein sign quality score of 1 or 2). In the subjective assessment of the HBP image quality, 93.9% of the high-FLIS group showed acceptable image quality, whereas 47.1% of the low-FLIS group showed suboptimal image quality (p < 0.001).
Table 2
Comparison of the Clinical, Imaging, and Biochemical Parameters between FLIS Groups in the Primary Analysis Set
Factors Associated with Low FLIS at the HBP of Gadoxetic Acid-Enhanced MRI
In the multivariable analysis, only the serum level of total bilirubin was an independent factor associated with low FLIS (adjusted odds ratio [OR] per 1-mg/dL increase, 1.64; 95% confidence interval [CI], 1.34–2.01; p < 0.001) (Table 3). In the subgroup analyses of 110 patients without biliary stents and 74 patients with biliary stents, the serum level of total bilirubin was also an independent factor associated with low FLIS (Supplementary Table 3), with an adjusted OR of 1.59 (95% CI, 1.23–2.05) and 1.96 (95% CI, 1.39–2.76), respectively. There was no significant association between the common duct diameter and low FLIS in both the main and subgroup analyses (p > 0.05).
Table 3
Factors Associated with the Low FLIS (FLIS 0–3 Points) at Hepatobiliary Phase Imaging of Gadoxetic Acid-Enhanced MRI in the Primary Analysis Set
Correlation Between the FLIS and Quantitative Parameters
The common duct diameter (r = -0.253; p = 0.001), serum levels of total bilirubin (r = -0.780; p < 0.001), AST (r = -0.436; p < 0.001), ALT (r = -0.387; p < 0.001), ALP (r = -0.473; p < 0.001), GGT (r = -0.295; p < 0.001), and creatinine (r = -0.031; p = 0.001) were negatively correlated with FLIS (Table 4). The level of albumin showed a positive correlation with FLIS (r = 0.251; p = 0.001).
Table 4
Correlation between FLIS and Quantitative Parameters
Prediction of Low FLIS
Figure 2 shows the area under the receiver operating curve (AUC) of serum total bilirubin for predicting low FLIS in the primary and validation sets. The AUC of serum total bilirubin for predicting low FLIS was 0.953 (95% CI: 0.914–0.982) in the primary analysis set and 0.956 (95% CI: 0.881–0.990) in the validation set. The optimal cutoff value of 2.1 mg/dL showed a sensitivity of 95.1% (95% CI: 88.9–98.4) and a specificity of 89.0% (95% CI: 80.2–94.9) in the primary analysis set. The criterion of serum total bilirubin ≥ 2.1 mg/dL showed the sensitivity and specificity of 92.1% (95% CI: 78.6–98.3) and 83.8% (95% CI: 68.0–93.8), respectively, for predicting low FLIS in the validation set.
Fig. 2
The graph shows the serum level of the total bilirubin for the prediction of low functional liver imaging score in the primary analysis and validation sets.
The area under the receiver operating characteristic curve was 0.953 (95% CI: 0.914–0.982) in the primary analysis set and 0.956 (95% CI: 0.881–0.990) in the validation set. The optimal cutoff value of the serum level of total bilirubin was 2.1 mg/dL with a sensitivity of 95.1% (95% CI: 88.9–98.4) and a specificity of 89.0% (95% CI: 80.2–94.9). CI = confidence interval
Characterization of Focal Liver Lesion
Among 184 patients in the primary analysis set, 45 (24.5%) had focal liver lesions, 23 (21.6%) in the high-FLIS group (Fig. 3) and 22 (28.0%) in the low-FLIS group (Table 5). The mean size of the target lesions was 1.1 ± 0.5 cm (range, 0.5–2.6 cm). The final diagnosis of the focal liver lesions included 34 abscesses and 11 metastases. In both reviewers, all lesions with poor conspicuity belonged to the low-FLIS group (p < 0.001) (Fig. 4). The sensitivity for diagnosing metastasis was lower in the low-FLIS group without statistical significance (50.0% vs. 100.0% in reviewer 1; 50.0% vs. 80.0% in reviewer 2) (Table 5).
Fig. 3
A 57-year-old male with distal bile duct cancer in the high-FLIS group.
The serum level of total bilirubin was 1.7 mg/dL. A. Contrast-enhanced CT image shows intraductal-growing distal bile duct cancer (arrow) and the dilated upstream common duct with a diameter of 15.0 mm. B. There is a small lesion with enhancement in periphery (arrow) in the liver segment VII. C, D. HBP images show hyperintensity of the liver (*, C) relative to the kidney (white arrowhead) (liver parenchymal enhancement quality score 2) and hypointensity of the portal vein (black arrowheads) relative to the liver (*, D) (portal vein sign quality score 2), but no biliary contrast excretion (biliary contrast excretion quality score 0). The FLIS is 4. E, F. The focal liver lesion (arrows) shows hypointensity on a precontrast T1WI (E) and rim enhancement on an arterial phase image (F). G. On the HBP image, the lesion is depicted as a hypointense lesion with a fuzzy margin (arrow) that is larger than those on the T1WI. Both reviewers determined it as definitely a micro-abscess. The lesion was not seen on contrast-enhanced CT obtained after 4 months and was considered a hepatic micro-abscess (not shown). FLIS = functional liver imaging score, HBP = hepatobiliary phase, T1WI = T1-weighted image
Fig. 4
A 71-year-old male with distal bile duct cancer in the low-FLIS group.
The serum level of total bilirubin was 8.3 mg/dL. A. Contrast-enhanced CT image shows periductal-infiltrating distal bile duct cancer (arrow) and the dilated upstream common duct with a diameter of 13.6 mm. B. There is a small peripheral enhancing lesion (arrow) in the liver segment VIII. C, D. HBP images show hypointensity of the liver (*, C) relative to the kidney (arrowhead) (liver parenchymal enhancement quality score 0), no biliary contrast excretion (biliary contrast excretion quality score 0), and hyperintensity of the portal vein (black arrowheads) relative to the liver (*, D) (portal vein sign quality score 0). The FLIS is 0. E, F. The focal liver lesion (arrows) shows hyperintensity in a diffusion-weighted image (E) and rim enhancement on an arterial phase image (F). G. On HBP image, the lesion does not appear to be distinguished (poor lesion conspicuity). Both reviewers were assigned as probably micro-abscess. H. A diffusion-weighted MR image obtained 2 months later reveals multiple hyperintense liver lesions with increased number and size, suggesting metastases. FLIS = functional liver imaging score, HBP = hepatobiliary phase
Table 5
Characterization for Focal Liver Lesion
The Interobserver Agreement for Imaging Assessment
The three FLIS parameters showed weighted κ values ranging from 0.84 to 0.93 (Supplementary Table 4). The 4-point grading of subjective assessment for the HBP image quality had a weighted κ of 0.78, and poor lesion conspicuity had a κ of 0.77. The distinction of liver metastasis vs. abscess for focal liver lesions showed κ of 0.77 in the high-FLIS group and κ of 0.49 in the low-FLIS group.
DISCUSSION
In patients with EHD cancer, the serum level of total bilirubin can be a predictor of the HBP image quality of MRI. Degradation of HBP images may affect the diagnostic performance for liver metastasis. The serum level of total bilirubin before MRI acquisition may help in the selection of MRI contrast agents in patients with EHD cancer, particularly when MRI is used as a problem-solving tool for the differential diagnosis between hepatic micro-abscesses and metastases.
The optimal cutoff of the serum level of total bilirubin for predicting low FLIS in our study was 2.1 mg/dL, which is similar to that (1.75 mg/dL and 2.18 mg/dL) of previous studies [3, 11]. In a previous study that included patients with liver cirrhosis using gadoxetic acid-enhanced MRCP, only 40% of patients with liver cirrhosis showed sufficient image quality for visualization of the biliary tree [3]. A serum level of total bilirubin ≥ 30 µmoL/L (1.75 mg/dL) was suggested as a cutoff value for insufficient visualization of the biliary tree on HBP images [3]. Another study revealed that patients with hyperintensity of the portal vein compared to that of the liver on the HBP image (“delayed hyperintense portal vein sign”) showed less biliary contrast excretion and higher levels of serum bilirubin [11]. The cutoff value of the total bilirubin for the delayed hyperintense portal vein sign was 2.18 mg/dL [11].
High bilirubin level is regarded as a relative contraindication for gadoxetic acid-enhanced MRI in some centers, with a cutoff value of bilirubin of 2.0–5.0 mg/dL [22, 23, 24]. The proposed cutoff is based on empirical data, mainly applied to patients with liver cirrhosis or chronic hepatitis, and there have been no established criteria for patients with biliary obstructions obtained through data analysis. According to the 2016 European Society of Gastrointestinal and Abdominal Radiology consensus statement, gadoxetic acid-enhanced MRI with MRCP can be obtained in the absence of liver function impairment or biliary obstruction, but there is no detailed cutoff value [25]. The cutoff value for total bilirubin from our study could be used as a criterion to assist in selecting an MR contrast agent before MRI acquisition is implemented in patients with EHD cancer.
In our study, 97.1% of the low-FLIS group showed no biliary contrast excretion, and biliary excretion seems to be most affected by biliary obstruction among the three HBP features of the FLIS. The mechanisms of hepatic absorption and excretion of Gd-EOB-DTPA are known as organic anion-transporting polypeptide 1B3-mediated hepatic uptake and multidrug resistance-associated protein 2 (MRP2)-mediated bile canalicular excretion [26]. Because Gd-EOB-DTPA shares the same transporters operative for bilirubin, there is reduced hepatic absorption and biliary excretion of Gd-EOB-DTPA in hyperbilirubinemia [27]. Interestingly, 52.9% of the low-FLIS group had acceptable HBP image quality, which is possibly due to preserved hepatic parenchymal enhancement apart from biliary excretion. Sun et al. [5] also reported that 67.1% of patients with bile duct cancer showed higher hepatic parenchymal enhancement on HBP images than on portal venous phase images, even though 86.3% did not show biliary contrast excretion. This suggests that excretion of highly cytotoxic bile salts is carefully regulated, and bile canalicular excretion is the rate-limiting step. The biliary excretion of Gd-EOB-DTPA is strictly restricted by the withdrawal of MRP2 from the canalicular membrane and shutting off of the canalicular excretion in the cholestatic liver [28, 29]. Given that biliary excretion is more severely impaired than hepatic parenchymal enhancement in cholestatic liver and that hepatic parenchymal enhancement affects the evaluation of focal liver lesions rather than biliary excretion, attention should be paid to the interpretation of the results of this study using the FLIS. This index reflects both hepatic parenchymal enhancement and biliary contrast excretion.
Contrary to our expectations, the dilated common duct was not related to suboptimal HBP image quality. This could be explained by the fact that the caliber of the common duct is influenced by various confounding factors, such as an intraductal mass [30] or insertion of a biliary stent, as well as the degree of bile duct obstruction. In the subgroup analysis, total bilirubin affected the FLIS in both groups with and without biliary stents. In an animal study that conducted bilioenteric anastomosis in 11 dogs that underwent common bile duct ligation, none of the liver function assessments were normalized after 7–10 days of biliary decompression [31]. In a study of 178 patients who underwent surgery for biliary obstruction, the rate of decrease in total bilirubin followed first-order kinetics and averaged 8% per day [32]. In this study, patients with high bilirubin levels at the time of MRI acquisition, even after biliary stent insertion, showed low FLIS. It is believed that there is insufficient time to recover liver function after biliary decompression.
This study had several limitations. First, there was a selection bias due to its retrospective nature. In particular, because we only included Bismuth type I cancer among patients with perihilar cancer, our results may not be generalizable to all EHD cancer patients. This approach was inevitable when using a reliable FLIS reflecting HBP image quality irrespective of the involvement of the right or left intrahepatic bile duct. In addition, since we hypothesized that the diameter of the dilated upstream common duct could be an important variable, we only included Bismuth type 1 cancer capable of diameter measurement. Second, this study was performed on a narrow study population focused on patients with EHD cancer. Further research in patients with diverse conditions, including other periampullary cancers, is needed. Third, a small number of patients with focal liver lesions were included in our study. Although the number of samples was small, we found that the lesion conspicuity and diagnostic performance for focal liver lesions were affected by FLIS. Fourth, MRI examinations were performed using a single 3T scanner, limiting the generalizability of our results. Lastly, we conducted temporal validation of the cutoff of the serum level of total bilirubin for predicting low FLIS using subjects in our institution. External validation using other subject groups must be performed sufficiently.
In conclusion, the serum level of total bilirubin before acquisition of gadoxetic acid-enhanced MRI may help predict suboptimal HBP image quality in patients with EHD cancer.
Supplement
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Conflicts of Interest:The authors have no potential conflicts of interest to disclose.
Author Contributions:
Conceptualization: Ji Hye Min.
Data curation: Ji Hye Min, Seo-Youn Choi, Ji Eun Lee.
Formal analysis: Jeong Ah Hwang, Ji Hye Min.
Investigation: Jeong Ah Hwang, Ji Hye Min.
Methodology: Ji Hye Min, Seong Hyun Kim.
Project administration: Ji Hye Min.
Resources: Jeong Ah Hwang, Ji Eun Lee, Ji Yoon Moon.
Supervision: Ji Hye Min, Seong Hyun Kim.
Validation: Jeong Ah Hwang, Ji Hye Min.
Visualization: Jeong Ah Hwang, Ji Hye Min.
Writing—original draft: Jeong Ah Hwang, Ji Hye Min.
Writing—review & editing: all authors.
Funding Statement:None
Availability of Data and Material
The datasets generated or analyzed during the study are not publicly available due the patient’s privacy but are available from the corresponding author on reasonable request.
References
-
Ichikawa T, Saito K, Yoshioka N, Tanimoto A, Gokan T, Takehara Y, et al. Detection and characterization of focal liver lesions: a Japanese phase III, multicenter comparison between gadoxetic acid disodium-enhanced magnetic resonance imaging and contrast-enhanced computed tomography predominantly in patients with hepatocellular carcinoma and chronic liver disease. Invest Radiol 2010;45:133–141.
-
-
Méndez RJ, Schiebler ML, Outwater EK, Kressel HY. Hepatic abscesses: MR imaging findings. Radiology 1994;190:431–436.
-
-
Bächler P, Baladron MJ, Menias C, Beddings I, Loch R, Zalaquett E, et al. Multimodality imaging of liver infections: differential diagnosis and potential pitfall. Radiographics 2016;36:1001–1023.
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