Diagnostic Accuracy of Gd-EOB-DTPA for Detection Hepatocellular Carcinoma (HCC): A Comparative Study with Dynamic Contrast Enhanced Magnetic Resonance Imaging (MRI) and Dynamic Contrast Enhanced Computed Tomography (CT)

Is there added value of the hepatobiliary phase of MRI with hepatobiliary contrast agents for hepatocellular carcinoma diagnosis? A meta-analysis

Purpose

So far, there have been published several meta-analyses which focused on hepatocellular carcinoma (HCC) detection with hepatobiliary phase (HBP) contrast agents. However, only a few of them aimed at establishing whether there is any added value of the HBP itself for HCC diagnosis. To answer the question, we performed a systematic literature search with the time limit going back to 2010.

Material and methods

True positive, false positive, false negative, and true negative values with and without the HBP were extracted from the included studies. Pooled sensitivities and specificities with and without the HBP were calculated and summary receiver operating characteristics curves were drawn to assess the diagnostic performance of the studies with and without the HBP.

Results

A total of 13 studies were included involving 1184 HCC lesions. In 13 studies without the HBP, the pooled sensitivity, specificity, and area under the curve (AUC) were 0.83, 0.89 and 0.94 respectively. In 13 studies with the HBP, the pooled sensitivity, specificity and AUC were 0.91, 0.85 and 0.98 respectively.

Conclusions

We found no statistically significant differences in sensitivities between studies with and without the HBP (p = 0.1651).

Diagnostic Values of the Liver Imaging Reporting and Data System in the Detection and Characterization of Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis

This review was undertaken to assess the diagnostic value of the Liver Imaging Reporting and Data System (LI-RADS) in patients with a high risk of hepatocellular carcinoma (HCC). Google Scholar, PubMed, Web of Science, Embase, PROQUEST, and Cochrane Library, as the international databases, were searched with appropriate keywords. Using the binomial distribution formula, the variance of all studies was calculated, and using Stata version 16 (StataCorp LLC, College Station, TX, USA), the obtained data were analyzed. Using a random-effect meta-analysis approach, we determined the pooled sensitivity and specificity. Utilizing the funnel plot and Begg's and Egger's tests, we assessed publication bias. The results exhibited pooled sensitivity and pooled specificity of 0.80% and 0.89%, respectively, with a 95% confidence interval (CI) of 0.76-0.84 and 0.87-0.92, respectively. The 2018 version of LI-RADS showed the greatest sensitivity (0.83%; 95% CI 0.79-0.87; I ² = 80.6%; P < 0.001 for heterogeneity; T ² = 0.001). The maximum pooled specificity was detected in LI-RADS version 2014 (American College of Radiology, Reston, VA, USA; 93.0%; 95% CI 89.0-96.0; I ² = 81.7%; P < 0.001 for heterogeneity; T ² = 0.001). In this review, the results of estimated sensitivity and specificity were satisfactory. Therefore, this strategy can serve as an appropriate tool for identifying HCC.

Contrast Agents for Hepatocellular Carcinoma Imaging: Value and Progression

Hepatocellular carcinoma (HCC) has the third-highest incidence in cancers and has become one of the leading threats to cancer death. With the research on the etiological reasons for cirrhosis and HCC, early diagnosis has been placed great hope to form a favorable prognosis. Non-invasive medical imaging, including the associated contrast media (CM)-based enhancement scan, is taking charge of early diagnosis as mainstream. Meanwhile, it is notable that various CM with different advantages are playing an important role in the different imaging modalities, or even combined modalities. For both physicians and radiologists, it is necessary to know more about the proper imaging approach, along with the characteristic CM, for HCC diagnosis and treatment. Therefore, a summarized navigating map of CM commonly used in the clinic, along with ongoing work of agent research and potential seeded agents in the future, could be a needed practicable aid for HCC diagnosis and prognosis.

DCE-MRI of esophageal carcinoma using star-VIBE compared with conventional 3D-VIBE

To investigate the value of the star-VIBE sequence in dynamic contrast-enhanced magnetic resonance imaging of esophageal carcinoma under free breathing conditions. From February 2019 to June 2020, 60 patients with esophageal carcinoma were prospectively enrolled to undergo dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with the K-space golden-angle radial stack-of-star acquisition scheme (star-VIBE) sequence (Group A) or conventional 3D volumetric-interpolated breath-hold examination (3D-VIBE) sequence (Group B), completely randomized grouping. The image quality of DCE-MRI was subjectively evaluated at five levels and objectively evaluated according to the image signal-to-noise ratio (SNR) and contrast-noise ratio (CNR). The DCE-MRI parameters of volume transfer constant (Ktrans), rate constant (Kep) and vascular extracellular volume fraction (Ve) were calculated using the standard Tofts double-compartment model in the post-perfusion treatment software TISSUE 4D (Siemens). Each group included 30 randomly selected cases. There was a significant difference in subjective classification between the groups (35.90 vs 25.10, p = 0.009). The study showed that both the SNR and CNR of group A were significantly higher than those of group B (p = 0.004 and < 0.001, respectively). There was no significant difference in Ktrans, Kep or Ve between the groups (all p > 0.05). The star-VIBE sequence can be applied in DCE-MRI examination of esophageal carcinoma, which can provide higher image quality than the conventional 3D-VIBE sequence in the free breathing state.

Computed tomography for the diagnosis of hepatocellular carcinoma in adults with chronic liver disease

BACKGROUND

Hepatocellular carcinoma occurs mostly in people with chronic liver disease and ranks sixth in terms of global incidence of cancer, and fourth in terms of cancer deaths. In clinical practice, computed tomography (CT) is used as a second-line diagnostic imaging modality to confirm the presence of focal liver lesions suspected as hepatocellular carcinoma on prior diagnostic test such as abdominal ultrasound or alpha-foetoprotein, or both, either in surveillance programmes or in clinical settings. According to current guidelines, a single contrast-enhanced imaging study CT or magnetic resonance imaging (MRI) showing typical hallmarks of hepatocellular carcinoma in people with cirrhosis is valid to diagnose hepatocellular carcinoma. However, a significant number of hepatocellular carcinomas do not show typical hallmarks on imaging modalities, and hepatocellular carcinoma is, therefore, missed. There is no clear evidence of the benefit of surveillance programmes in terms of overall survival: the conflicting results can be a consequence of inaccurate detection, ineffective treatment, or both. Assessing the diagnostic accuracy of CT may clarify whether the absence of benefit could be related to underdiagnosis. Furthermore, an assessment of the accuracy of CT in people with chronic liver disease, who are not included in surveillance programmes is needed for either ruling out or diagnosing hepatocellular carcinoma.

OBJECTIVES

Primary: to assess the diagnostic accuracy of multidetector, multiphasic contrast-enhanced CT for the diagnosis of hepatocellular carcinoma of any size and at any stage in adults with chronic liver disease, either in a surveillance programme or in a clinical setting. Secondary: to assess the diagnostic accuracy of CT for the diagnosis of resectable hepatocellular carcinoma in adults with chronic liver disease.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Trials Register, Cochrane Hepato-Biliary Diagnostic-Test-Accuracy Studies Register, the Cochrane Library, MEDLINE, Embase, LILACS, Science Citation Index Expanded, and Conference Proceedings Citation Index - Science until 4 May 2021. We applied no language or document-type restrictions.

SELECTION CRITERIA

Studies assessing the diagnostic accuracy of CT for the diagnosis of hepatocellular carcinoma in adults with chronic liver disease, with cross-sectional designs, using one of the acceptable reference standards, such as pathology of the explanted liver and histology of resected or biopsied focal liver lesion with at least a six-month follow-up.

DATA COLLECTION AND ANALYSIS

At least two review authors independently screened studies, extracted data, and assessed the risk of bias and applicability concerns, using the QUADAS-2 checklist. We presented the results of sensitivity and specificity, using paired forest plots, and tabulated the results. We used a hierarchical meta-analysis model where appropriate. We presented uncertainty of the accuracy estimates using 95% confidence intervals (CIs). We double-checked all data extractions and analyses.

MAIN RESULTS

We included 21 studies, with a total of 3101 participants. We judged all studies to be at high risk of bias in at least one domain because most studies used different reference standards, often inappropriate to exclude the presence of the target condition, and the time-interval between the index test and the reference standard was rarely defined. Regarding applicability in the patient selection domain, we judged 14% (3/21) of studies to be at low concern and 86% (18/21) of studies to be at high concern owing to characteristics of the participants who were on waiting lists for orthotopic liver transplantation. CT for hepatocellular carcinoma of any size and stage: sensitivity 77.5% (95% CI 70.9% to 82.9%) and specificity 91.3% (95% CI 86.5% to 94.5%) (21 studies, 3101 participants; low-certainty evidence). CT for resectable hepatocellular carcinoma: sensitivity 71.4% (95% CI 60.3% to 80.4%) and specificity 92.0% (95% CI 86.3% to 95.5%) (10 studies, 1854 participants; low-certainty evidence). In the three studies at low concern for applicability (861 participants), we found sensitivity 76.9% (95% CI 50.8% to 91.5%) and specificity 89.2% (95% CI 57.0% to 98.1%). The observed heterogeneity in the results remains mostly unexplained. The sensitivity analyses, which included only studies with clearly prespecified positivity criteria and only studies in which the reference standard results were interpreted without knowledge of the results of the index test, showed no variation in the results.

AUTHORS' CONCLUSIONS

In the clinical pathway for the diagnosis of hepatocellular carcinoma in adults with chronic liver disease, CT has roles as a confirmatory test for hepatocellular carcinoma lesions, and for staging assessment. We found that using CT in detecting hepatocellular carcinoma of any size and stage, 22.5% of people with hepatocellular carcinoma would be missed, and 8.7% of people without hepatocellular carcinoma would be unnecessarily treated. For resectable hepatocellular carcinoma, we found that 28.6% of people with resectable hepatocellular carcinoma would improperly not be resected, while 8% of people without hepatocellular carcinoma would undergo inappropriate surgery. The uncertainty resulting from the high risk of bias in the included studies and concerns regarding their applicability limit our ability to confidently draw conclusions based on our results.

Injection rate of contrast medium affects diagnostic ability of dynamic contrast-enhanced magnetic resonance imaging for endometrial carcinoma: a prospective cohort study

Background

Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) can obtain semi-quantitative or quantitative parameters of tumors by capturing the images before and after injection of contrast medium. However, there has been no further research on the effect of flow rate of contrast medium on image quality and parameter sensitivity of DCE-MRI in endometrial carcinoma (EC).

Methods

This was a prospective cohort study enrolling patients who were suspected of EC between January 2018 and June 2020. The baseline data of participants were collected. Post-surgical histological examination acted as the gold standard of EC diagnosis and some characteristics of tumors were recorded. We calculated 3 important parameters of DCE-MRI, including volume transfer constant (K^trans), flux rate constant (K_ep), and extravascular extracellular volume fraction (V_e), according to the MRI system. The image quality in DCE-MRI imaging was evaluated according to contrast, resolution, artifact, signal-to-noise ratio, and scanning time. To evaluate the diagnostic ability of DCE-MRI with different injection rate, receiver operating characteristic (ROC) curve was generated and the area under curve (AUC) was calculated.

Results

According to the different injection rate of contrast medium, participants were divided into three groups, including 2, 3, and 4 mL/s group. It was found that there were more grade 1 EC in the 3 mL/s group (52.4%) than other two groups (34.3% and 23.3%, respectively), and the difference was significant (P=0.021). No other significant differences were found among all other variables. It was found that K^trans was much higher in the 4 mL/s group than in other two groups (P<0.001). Also, V_e was much higher in the 4 mL/s group than in other two groups (P<0.001). However, no significant difference was found in K_ep between three groups (P=0.633). Besides, the 4 mL/s group had the highest quality of all three groups (P<0.001). The sensitivity, specificity, and accuracy were highest in 4 mL/s group. The AUC in three groups were 0.822, 0.832, and 0.888 in the 2, 3, and 4 mL/s group, respectively.

Conclusions

The DCE-MRI measurement is useful for the diagnosis of EC, and faster injection rate may be beneficial to improve diagnostic accuracy and image quality.

Is Gadoxetic Acid Disodium (Gd-EOB-DTPA)-Enhanced Magnetic Resonance Imaging an accurate diagnostic method for Hepatocellular Carcinoma? a systematic review with meta-analysis

Background： Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) has become a widely used liver-specific contrast agent worldwide, but its value and limitations as a diagnostic technique with hepatocellular carcinoma (HCC), have not been assessed.

INTRODUCTION

A review of the latest evidence available on the diagnostic value of Gd-EOB-DTPA-enhanced MRI for the evaluation of HCC is reported.

METHODS

A systematic, comprehensive literature search was conducted with PubMed, Scopus, EMBASE, the Web of Science, the Cochrane Library, CNKI, vip, wanfangdata and CBM from inception to June 31, 2020. The QUADAS-2 tool was used to evaluate the quality of the included studies. Pooled sensitivity (SEN), pooled specificity (SPE), pooled positive likelihood ratio (PLR), pooled negative likelihood ratio (NLR), pooled diagnostic odds ratio (dOR) and summary receiver operating characteristic (SROC) curves were calculated to assess the diagnostic value of the individual diagnostic tests.

RESULTS

A total of 47 articles were included, involving a total of 6362 nodules in 37 studies based on per-lesion studies. There were 13 per-patient studies, including a total of 1816 patients. The results of the meta-analysis showed that the per-lesion studies pooled weighted values were SEN 0.90 [95% confidence interval (CI): 0.87-0.92], SPE 0.92 (95%CI: 0.90-0.94), PLR 11.6 (95%CI: 8.8-15.2), NLR 0.11 (95%CI: 0.09-0.14) and dOR 107.0 (95%CI: 74.0-155.0). The AUC of the SROC curve was 0.96. The per-patient studies pooled weighted values were SEN 0.84 [95% confidence interval (CI): 0.78-0.89], SPE 0.92 (95%CI: 0.88-0.94), PLR 10.4 (95%CI: 7.4-14.6), NLR 0.17 (95%CI: 0.12-0.24) and dOR 61.0 (95%CI: 42.0-87.0). The AUC of the SROC curve was 0.95 and subgroup analyses were performed.

CONCLUSIONS

The diagnostic value of Gd-EOB-DTPA for HCC was quantitatively evaluated in a per-lesion study and a per-patient study using a systematic review of the literature. A positive conclusion was drawn: Gd-EOB-DTPA-enhanced imaging is a valuable diagnostic technique for HCC. The size of the nodules and the selection of the imaging diagnostic criteria may affect the diagnostic sensitivity.

State of the art in abdominal MRI structured reporting: a review

In the management of several abdominal disorders, magnetic resonance imaging (MRI) has the potential to significantly improve patient's outcome due to its diagnostic accuracy leading to more appropriate treatment choice. However, its clinical value heavily relies on the quality and quantity of diagnostic information that radiologists manage to convey through their reports. To solve issues such as ambiguity and lack of comprehensiveness that can occur with conventional narrative reports, the adoption of structured reporting has been proposed. Using a checklist and standardized lexicon, structured reports are designed to increase clarity while assuring that all key imaging findings related to a specific disorder are included. Unfortunately, structured reports have their limitations too, such as risk of undue report simplification and poor template plasticity. Their adoption is also far from widespread, and probably the ideal balance between radiologist autonomy and report consistency of has yet to be found. In this article, we aimed to provide an overview of structured reporting proposals for abdominal MRI and of works assessing its value in comparison to conventional free-text reporting. While for several abdominal disorders there are structured templates that have been endorsed by scientific societies and their adoption might be beneficial, stronger evidence confirming their imperativeness and added value in terms of clinical practice is needed, especially regarding the improvement of patient outcome.

Application of Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common malignant tumor of the liver, and its morbidity and mortality have been increasing in recent years. The early diagnosis and prompt treatment of small HCC are crucial to improve the prognosis and quality of life of patients. In China, hepatitis B virus infection is the main cause. HCC with a single tumor nodule of ≤ 3 cm in diameter, or HCC with a number of nodules, in which each nodule is ≤ 2 cm in diameter, with a total diameter of ≤ 3 cm, is considered as small HCC. The MRI liver-specific contrast agent can detect small HCC at the early stage. This has important clinical implications for improving the survival rate of patients.

MAIN BODY

Gd-EOB-DTPA-enhanced MRI can significantly improve the sensitivity and specificity of the detection of HBV-related small hepatocellular carcinoma, providing an important basis for the clinical selection of appropriate personalized treatment. Gd-EOB-DTPA-enhanced MRI can reflect the degree of HCC differentiation, and the evaluation of HCC on Gd-EOB-DTPA-enhanced MRI would be helpful for the selection of the treatment and prognosis of HCC patients. The present study reviews the progress of the application of Gd-EOB-DTPA in the early diagnosis of small HCC, its clinical treatment, the prediction of the degree of differentiation, and the assessment of recurrence and prognosis of HCC, including the pharmacoeconomics and application limitations of Gd-EOB-DTPA. The value of the application of HCC with the Gd-EOB-DTPA was summarized to provide information for improving the quality of life and prolonging the survival of patients.

CONCLUSION

Gd-EOB-DTPA-enhanced MRI has the diagnostic capability for small HCC with a diameter of ≤ 2 cm. This will have a broader application prospect in the early diagnosis of small liver cancer with a diameter of ≤ 1 cm in the future. The relationship between GD-EOB-DTPA-MRI and the degree of HCC differentiation has a large research space, and Gd-EOB-DTPA is expected to become a potential tool for the preoperative prediction and postoperative evaluation of HCC, which would be beneficial for more appropriate treatments for HCC patients.

Application of Image Fusion in Diagnosis and Treatment of Liver Cancer

With the accelerated development of medical imaging equipment and techniques, image fusion technology has been effectively applied for diagnosis, biopsy and radiofrequency ablation, especially for liver tumor. Tumor treatment relying on a single medical imaging modality might face challenges, due to the deep positioning of the lesions, operation history and the specific background conditions of the liver disease. Image fusion technology has been employed to address these challenges. Using the image fusion technology, one could obtain real-time anatomical imaging superimposed by functional images showing the same plane to facilitate the diagnosis and treatments of liver tumors. This paper presents a review of the key principles of image fusion technology, its application in tumor treatments, particularly in liver tumors, and concludes with a discussion of the limitations and prospects of the image fusion technology.

The diagnostic performance of gadoxetic acid disodium-enhanced magnetic resonance imaging and contrast-enhanced multi-detector computed tomography in detecting hepatocellular carcinoma: a meta-analysis of eight prospective studies

AIM

The purpose of this study was to determine the relative diagnostic benefit of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) over contrast-enhanced multi-detector computed tomography (CEMDCT) for the detection of hepatocellular carcinoma (HCC).

METHODS

Two investigators searched multiple databases from inception to January 8, 2019, for studies comparing Gd-EOB-DTPA-enhanced MRI with CEMDCT in adults suspected of HCC. Two reviewers independently selected studies and extracted data.

RESULTS

Eight studies were included enrolling 498 patients. MRI showed significantly higher sensitivity than CT (0.85 vs. 0.68). There was no significant difference in the specificity of MRI and CT (0.94 vs. 0.93). The negative likelihood ratio and positive likelihood ratio of MRI and CT were not significantly different (0.16 vs. 0.15 and 14.7 vs. 11.2, respectively). The summary receiver operating characteristics (SROC) of MRI was higher than that of CT at 0.96 vs. 0.91. In the subgroup analysis with a lesion diameter below 2 cm, the sensitivity of MRI was significantly higher than that of CT (0.79 vs. 0.46).

CONCLUSION

Gd-EOB-DTPA-enhanced MRI showed higher sensitivity and overall diagnostic accuracy than CEMDCT especially for hepatocellular carcinoma lesions smaller than 2 cm.

KEY POINTS

• Gd-EOB-DTPA-enhanced MRI can detect small lesions of hepatocellular carcinoma. • Gd-EOB-DTPA-enhanced MRI showed higher sensitivity and overall diagnostic accuracy than CEMDCT in patients with hepatocellular carcinoma. • Eight prospective studies showed that Gd-EOB-DTPA-enhanced MRI provides greater diagnostic confidence.

Combining the Arterial Phase of Contrast-Enhanced Ultrasonography, Gadoxetic Acid-Enhanced Magnetic Resonance Imaging and Diffusion-Weighted Imaging in the Diagnosis of Hepatic Nodules ≤20 mm in Patients with Cirrhosis

Contrast-enhanced ultrasonography (CEUS) and gadoxetic acid-enhanced magnetic resonance imaging (EOB-MRI) were compared with respect to diagnostic efficacy in the detection of small hepatocellular carcinoma. A new diagnostic strategy that combines the arterial phase of CEUS, the hepatobiliary phase of EOB-MRI and diffusion-weighted MR imaging (DWI) is described. One hundred sixteen nodules were enrolled to validate the performance of the strategy. For lesions ≤20 mm in size, the areas under the receiver operating characteristic curves (Az) of CEUS and EOB-MRI were 0.930 (95% confidence interval [CI]: 0.867-0.969) and 0.920 (95% CI: 0.855-0.962) (p = 0.796), respectively. The Az value of the new diagnostic strategy was 0.985 (95% CI: 0.942-0.999) (vs. CEUS, p = 0.026; vs. EOB-MRI, p = 0.014). The sensitivity, specificity and diagnostic accuracy of the new strategy were 95.5% (95% CI: 88.9%-98.8%), 96.3% (95% CI: 81.0%-99.9%) and 95.7% (95% CI: 91.9%-99.4%), respectively. The new diagnostic strategy based on the arterial phase of CEUS, hepatobiliary phase of EOB-MRI and DWI represents an appealing solution for distinguishing small hepatocellular carcinomas from benign lesions, especially when the nodules present atypical enhancement patterns.

Optimization of hepatobiliary phase delay time of Gd-EOB-DTPA-enhanced magnetic resonance imaging for identification of hepatocellular carcinoma in patients with cirrhosis of different degrees of severity

AIM

To optimize the hepatobiliary phase delay time (HBP-DT) of Gd-EOB-DTPA-enhanced magnetic resonance imaging (GED-MRI) for more efficient identification of hepatocellular carcinoma (HCC) occurring in different degrees of cirrhosis assessed by Child-Pugh (CP) score.

METHODS

The liver parenchyma signal intensity (LPSI), the liver parenchyma (LP)/HCC signal ratios, and the visibility of HCC at HBP-DT of 5, 10, 15, 20, and 25 min (i.e., DT-5, DT-10, DT-15, DT-20, and DT-25 ) after injection of Gd-EOB-DTPA were collected and analyzed in 73 patients with cirrhosis of different degrees of severity (including 42 patients suffering from HCC) and 18 healthy adult controls.

RESULTS

The LPSI increased with HBP-DT more significantly in the healthy group than in the cirrhosis group (F = 17.361, P < 0.001). The LP/HCC signal ratios had a significant difference (F = 12.453, P < 0.001) among various HBP-DT points, as well as between CP-A and CP-B/C subgroups (F = 9.761, P < 0.001). The constituent ratios of HCC foci identified as obvious hypointensity (+++), moderate hypointensity (++), and mild hypointensity or isointensity (+/-) kept stable from DT-10 to DT-25: 90.6%, 9.4%, and 0.0% in the CP-A subgroup; 50.0%, 50.0%, and 0.0% in the CP-B subgroup; and 0.0%, 0.0%, and 100.0% in the CP-C subgroup, respectively.

CONCLUSION

The severity of liver cirrhosis has significant negative influence on the HCC visualization by GED-MRI. DT-10 is more efficient and practical than other HBP-DT points to identify most of HCC foci emerging in CP-A cirrhosis, as well as in CP-B cirrhosis; but an HBP-DT of 15 min or longer seems more appropriate than DT-10 for visualization of HCC in patients with CP-C cirrhosis.

Computational Modeling in Liver Surgery

The need for extended liver resection is increasing due to the growing incidence of liver tumors in aging societies. Individualized surgical planning is the key for identifying the optimal resection strategy and to minimize the risk of postoperative liver failure and tumor recurrence. Current computational tools provide virtual planning of liver resection by taking into account the spatial relationship between the tumor and the hepatic vascular trees, as well as the size of the future liver remnant. However, size and function of the liver are not necessarily equivalent. Hence, determining the future liver volume might misestimate the future liver function, especially in cases of hepatic comorbidities such as hepatic steatosis. A systems medicine approach could be applied, including biological, medical, and surgical aspects, by integrating all available anatomical and functional information of the individual patient. Such an approach holds promise for better prediction of postoperative liver function and hence improved risk assessment. This review provides an overview of mathematical models related to the liver and its function and explores their potential relevance for computational liver surgery. We first summarize key facts of hepatic anatomy, physiology, and pathology relevant for hepatic surgery, followed by a description of the computational tools currently used in liver surgical planning. Then we present selected state-of-the-art computational liver models potentially useful to support liver surgery. Finally, we discuss the main challenges that will need to be addressed when developing advanced computational planning tools in the context of liver surgery.

Preoperative Assessment of Hepatocellular Carcinoma with Split-Bolus Combined Phase Contrast-Enhanced Computed Tomography

Background

The aim of this study was to investigate the feasibility of a split-bolus combined phase contrast-enhanced computed tomography protocol in evaluation of liver vasculature in hepatocellular carcinoma (HCC) patients for the purpose of surgery guidance.

Material/Methods

Two groups of patients were recruited for the study: 24 consecutive cases of HCC who underwent multiphasic CT examination, and 22 consecutive cases who afterwards underwent split-bolus combined phase CT examination. The multiphasic protocol included an unenhanced scan and 3 image acquisitions after contrast injection. The injection of contrast medium was 440 mgI/kg in a single bolus. The split-bolus combined phase protocol included unenhanced scan and combined phase. The injection of contrast medium was 440 mgI/kg for the first bolus and 220 mgI/kg for the second bolus. The vascular delineation was evaluated with Likert scales. The CT values were measured, and the contrast-to-noise ratio (CNR) was calculated. We also compared the effective radiation dose (ED) of the 2 protocols.

Results

All mean CT values were significantly higher in the split-bolus protocol than in the multiphasic protocol (all P<.05), except for the hepatic vein (P>.05). The ED was significantly lower in the split-bolus protocol, corresponding to a dose reduction of 66% compared to the multiphasic protocol (P<.05). The scores of the branches of the hepatic vein in the split-bolus protocol were not lower than those in the multiphasic protocol.

Conclusions

For the preoperative HCC patients, the split-bolus combined phase CT examination meets the diagnostic requirement of surgical planning, with approximately 60% reduction in the radiation dose.