FEASIBILITY STUDY OF AN ULTRASOUND CONTRAST AGENT(LEVOVIST) IN COLOR DOPPLER IMAGING OF LIVER NEOPLASMS

The purpose of this study was to determine the efficacy of using an ultrasound contrast agent(levovist)to enhance the color Doppler imaging of liver neoplasms.Thirty patients with hepatic tumors were enrolled in this study.After intravenous administration of levovist,the color Doppler signals of normal hepatic vessels were enhanced.In various hepatic tumors,the different patterns of tumor vascularity were observed,which had not been demonstrated in conventional non contrast color Doppler imaging.In 11 of 16 patients with hepatocarcinoma,additional color Doppler signals were observed in the central part of the tumors.On the contrary,3 patients with metastatic liver lesions the enhanced color Doppler signals appear only at the peripheral of tumors.A typical rim like color enhancement was seen in 2 of the 3 cases.In six patients with hepatic hemangiomas contrast enhanced color Doppler imaging demonstrated the blood vessels at the margin of the neoplasms.Contrast enhanced color Doppler imaging improves the visualization of the hepatic neoplasm vascularity.This technique holds great promise for detecting small liver tumors and differentiating hepatic neoplasms.

Comparison of the Imaging Manifestations and Diagnostic Values of Multi-slice Spiral CT and Enhanced MRI Scans of Primary Liver Cancer(PLC)Intrahepatic Lesions

Objective:To compare and analyze the clinical diagnostic value of multi-slice spiral CT and enhanced MRI for primary liver cancer(PLC),and to summarize the imaging findings.Methods:The research subjects in this article were 50 patients with PLC who were admitted to our hospital from 2017 April to 2018 September.After the patients were admitted,they were examined by multi-slice spiral CT and enhanced MRI scanning,and the pathological diagnosis results were followed up.Relevant information was reviewed and analyzed.Results:The detection rate of multi-slice spiral CT was higher than that of MRI in the portal venous phase lesion detection.The difference was statistically significant(P<0.05).The detection rate of lesions in the arterial phase and delayed phase was not statistically significant(P>0.05);the diagnostic accuracy of multi-slice spiral CT was 85.96%,and the diagnostic accuracy of enhanced MRI scanning was 91.11%,which was not statistically significant(P>0.05).MRI scans showed the capsules of primary liver cancer better than CT,but the difference was not statistically significant(P>0.05).Conclusion:In conclusion,both multi-slice spiral CT and enhanced MRI can be used for the effective diagnosis of primary liver cancer intrahepatic lesions.The diagnostic value of the two is equivalent,but enhanced MRI has a slightly higher diagnostic accuracy and can be used as the preferred method.

Exploring non-invasive diagnostics for metabolic dysfunctionassociated fatty liver disease

The population with metabolic dysfunction-associated fatty liver disease(MAFLD)is increasingly common worldwide.Identification of people at risk of progression to advanced stages is necessary to timely offer interventions and appropriate care.Liver biopsy is currently considered the gold standard for the diagnosis and staging of MAFLD,but it has associated risks and limitations.This has spurred the exploration of non-invasive diagnostics for MAFLD,especially for steatohepatitis and fibrosis.These non-invasive approaches mostly include biomarkers and algorithms derived from anthropometric measurements,serum tests,imaging or stool metagenome profiling.However,they still need rigorous and widespread clinical validation for the diagnostic performance.

Effective use of the Japan Narrow Band Imaging Expert Team classification based on diagnostic performance and confidence level

Five years have passed since the Japan Narrow Band Imaging Expert Team (JNET) classification was proposed in 2014. However, the diagnostic performance of this classification has not yet been established. We conducted a retrospective study and a systematic search of Medical Literature Analysis and Retrieval System On-Line. There were three retrospective single center studies about the diagnostic performance of this classification. In order to clarify this issue, we reviewed our study and three previous studies. This review revealed the diagnostic performance in regards to three important differentiations.(1) Neoplasia from non-neoplasia;(2) malignant neoplasia from benign neoplasia;and (3) deep submucosal invasive cancer (D-SMC) from other neoplasia. The sensitivity in differentiating neoplasia from non-neoplasia was 98.1%-99.8%. The specificity in differentiating malignant neoplasia from benign neoplasia was 84.7%-98.2% and the specificity in the differentiation D-SMC from other neoplasia was 99.8%-100.0%. This classification would enable endoscopists to identify almost all neoplasia, to appropriately determine whether to perform en bloc resection or not, and to avoid unnecessary surgery. This article is the first review about the diagnostic performance of the JNET classification. Previous reports about the diagnostic performance have all been retrospective single center studies. A large-scale prospective multicenter evaluation study is awaited for the validation.

Imaging features of intraductal papillary mucinous neoplasms of the pancreas in multi-detector row computed tomography

AIM:To retrospectively evaluate the imaging features of pancreatic intraductal papillary mucinous neoplasms (IPMNs) in multi-detector row computed tomography (MDCT).METHODS: A total of 20 patients with pathologically-confirmed intraductal papillary mucinous neoplasms (IPMNs) were included in this study. Axial MDCT images combined with CT angiography (CTA) and multiplanar volume reformations (MPVR) or curved reformations (CR) were preoperatively acquired. Two radiologists (Tan L and Wang DB) reviewed all the images in consensus using an interactive picture archiving and communication system. The disputes in readings were resolved through consultation with a third experienced radiologist (Chen KM). Finally, the findings and diagnoses were compared with the pathologic results.RESULTS: The pathological study revealed 12 malignant IPMNs and eight benign IPMNs. The diameters of the cystic lesions and main pancreatic ducts (MPDs) were significantly larger in malignant IPMNs compared with those of the benign IPMNs (P<0.05). The combined-type IPMNs had a higher rate of malignancy than the other two types of IPMNs (P<0.05). Tumors with mural nodules and thick septa had a significantly higher incidence of malignancy than tumors without these features (P<0.05). Communication of side-branch IPMNs with the MPD was present in nine cases at pathologic examination. Seven of them were identified from CTA and MPVR or CR images. From comparison with the pathological diagnosis, the sensitivity, specificity, and accuracy of MDCT in characterizing the malignancy of IPMN of the pancreas were determined to be 100%, 87.5% and 95%, respectively.CONCLUSION: MDCT with CTA and MPVR or CR techniques can elucidate the imaging features of IPMNs and help predict the malignancy of these tumors.

Diffusion weighted imaging in the liver

Diffusion weighted magnetic resonance imaging (DWI) is an imaging technique which provides tissue contrast by the measurement of diffusion properties of water molecules within tissues. Diffusion is expressed in an apparent diffusion coefficient (ADC), which reflects the diffusion properties unique to each type of tissue. DWI has been originally used in neuroradiology. More recently, DWI has increasingly been used in addition to conventional unenhanced and enhanced magnetic resonance imaging (MRI) in other parts of the body. The reason for this delay was a number of technical problems inherent to the technique, making DWI very sensitive to artifacts, which had to be overcome. With assessment of ADC values, DWI proved to be helpful in characterization of focal liver lesions. However, DWI should always be used in conjunction to conventional MRI since there is considerable overlap between ADC values of benign and malignant lesions. DWI is useful in the detection of hepatocellular carcinoma in the cirrhotic liver and detection of liver metastases in oncological patients. In addition, DWI is a promising tool in the prediction of tumor responsiveness to chemotherapy and the follow-up of oncological patients after treatment, as DWI may be capable of detecting recurrent disease earlier than conventional imaging.This review focuses on the most common applications of DWI in the liver.

Quantification of angiogenesis by CT perfusion imaging in liver tumor of rabbit

BACKGROUND:Tumor angiogenesis is essential for primary and metastatic tumor growth.Computed tomography perfusion(CTP)is a new imaging method,made possible by the recent development of fast CT scanners and improved data analysis techniques,which allows measurement of the physiologic and hemodynamic properties of tissue vasculature.This study aimed to evaluate CTP in the quantification of angiogenesis and to assess the relationship between tissue perfusion parameters and microvascular density(MVD)and vascular endothelial growth factor(VEGF),attempting to detect the physiologic properties of angiogenesis.METHODS:Sixteen rabbits with VX2 liver tumors underwent multi-slice CT perfusion(MSCTP)on day 14 after tumor inoculation.CTP parameters included hepatic blood flow(HBF),hepatic blood volume(HBV),mean transit time(MTT),permeability of capillary vessel surface(PS),hepatic artery index(HAI),hepatic artery perfusion(HAP),and hepatic portal perfusion(HPP).The border of the tumor was stained with CD34 and VEGF immunohistochemical stains,and MVD was measured by anti-CD34.Then,CTP parameters were determined whether they were correlated with MVD and VEGF using Pearson’s correlation coefficient.RESULTS:The positive expression of MVD was different in the center and border of the tumor(P【0.01).There was a positive correlation between MVD and VEGF in the border(P【0.05).As more VEGF was expressed,the number of microvessels increased.Correlation analyses were also made between the perfusion parameters and MVD and VEGF in the border of the tumor.HBF,PS,HAI,and HAP values were positively correlated with MVD and VEGF(P【0.05),HPP was negatively correlated with MVD and VEGF(P【0.01),and HBV and MTT values were not correlated with MVD and VEGF(P】0.05).CONCLUSIONS:Significant correlations were found between perfusion parameters and MVD and VEGF.Therefore,MSCTP can be used to evaluate tumor angiogenesis in vivo.

Diagnostic value of the fluoroscopic triggering 3D LAVA technique for primary liver cancer

BACKGROUND: Primary liver cancer (PLC) is one of the common malignant tumors. Liver acquisition with acceleration volume acquisition (LAVA), which allows simultaneous dynamic enhancement of the hepatic parenchyma and vasculature imaging, is of great help in the diagnosis of PLC. This study aimed to evaluate application of the fluoroscopic triggering 3D LAVA technique in the imaging of PLC and liver vasculature. METHODS: The clinical data and imaging findings of 38 adults with PLC (22 men and 16 women; average age 52 years), pathologically confirmed by surgical resection or biopsy, were collected and analyzed. All magnetic resonance images were obtained with a 1.5-T system (General Electrics Medical Systems) with an eight-element body array coil and application of the fluoroscopic triggering 3D LAVA technique. Overall image quality was assessed on a 5-point scale by two experienced radiologists. All the nodules and blood vessel were recorded and compared. The diagnostic accuracy and feasibility of LAVA were evaluated. RESULTS: Thirty-eight patients gave high quality images of 72 nodules in the liver for diagnosis. The accuracy of LAVA was 97.2% (70/72), and the coincidence rate between the extent of tumor judged by dynamic enhancement and pathological examination was 87.5% (63/72). Displayed by the maximum intensity projection reconstruction, nearly all cases gave satisfactory images of branches III and IV of the hepatic artery. Furthermore, small early-stage enhancing hepatic lesions and the parallel portal vein were also well displayed. CONCLUSIONS: Sequence of LAVA provides good multi-phase dynamic enhancement scanning of hepatic lesions. Combined with conventional scanning technology, LAVA effectively and safely displays focal hepatic lesions and the relationship between tumor and normal tissues, especially blood vessels. (Hepatobiliary Pancreat Dis Int 2010; 9: 159-163)

Magnetic resonance imaging of the liver:New imaging strategies for evaluating focal liver lesions

The early detection of focal liver lesions,particularly those which are malignant,is of utmost importance.The resection of liver metastases of some malignancies(including colorectal cancer)has been shown to improve the survival of patients.Exact knowledge of the number,size,and regional distribution of liver metastases is essential to determine their resectability.Almost all focal liver lesions larger than 10 mm are demonstrated with current imaging techniques but the detection of smaller focal liver lesions is still relatively poor.One of the advantages of magnetic resonance imaging(MRI)of the liver is better soft tissue contrast(compared to other radiologic modalities),which allows better detection and characterization of the focal liver lesions in question.Developments in MRI hardware and software and the availability of novel MRI contrast agents have further improved the diagnostic yield of MRI in lesion detection and characterization.Although the primary modalities for liver imaging are ultrasound and computed tomography,recent studies have suggested that MRI is the most sensitive method for detecting small liver metastatic lesions,and MRI is now considered the pre-operative standard method for diagnosis.Two recent developments in MRI sequences for the upper abdomen comprise unenhanced diffusion-weighted imaging(DWI),and keyhole-based dynamic contrast-enhanced(DCE)MRI(4D THRIVE).DWI allows improved detection(b=10 s/mm2)of small(<10 mm)focal liver lesions in particular,and is useful as a road map sequence.Also,using higher b-values,the calculation of the apparent diffusion coefficient value,true diffusion coefficient,D,and the perfusion fraction,f,has been used for the characterization of focal liver lesions.DCE 4D THRIVE enables MRI of the liver with high temporal and spatial resolution and full liver coverage.4D THRIVE improves evaluation of focal liver lesions,providing multiple arterial and venous phases,and allows the calculation of perfusion parameters using pharmacokinetic models.4D THRIVE has potential benefits in terms of detection,characterization and staging of focal liver lesions and in monitoring therapy.

Benign focal liver lesions:The role of magnetic resonance imaging

Liver lesions are common findings in radiologists’daily routine.They are a complex category of pathology that range from solitary benign lesions to primary liver cancer and liver metastases.Benign focal liver lesions can arise from different liver cell types:Epithelial(hepatocytes and biliary cells)and nonepithelial(mesenchymal cells).Liver magnetic resonance imaging(MRI)is a fundamental radiological method in these patients as it allows with its multiparametric approach optimal non-invasive tissue characterization.Furthermore,advanced liver MRI techniques such as diffusion-weighted imaging and hepatobiliary contrast agents have improved the detection of focal liver lesions and can be highly effective in differentiating pseudotumor from tumors,as well as benign from malignant lesions,and can also be used for differential diagnosis.Although histological examination can be useful in making a definitive diagnosis,MRI is an important modality in the diagnosis of liver lesions with a significant impact on patient care.This aim of this review is to provide a comprehensive overview of benign liver lesions on MRI.

Prognostication and response assessment in liver and pancreatic tumors:The new imaging

Diffusion-weighted imaging(DWI), dynamic contrastenhanced magnetic resonance imaging(DCE-MRI) and perfusion computed tomography(CT) are technical improvements of morphologic imaging that can evaluate functional properties of hepato-bilio-pancreatic tumors during conventional MRI or CT examinations.Nevertheless, the term "functional imaging" is commonly used to describe molecular imaging techniques, as positron emission tomography(PET)CT/MRI, which still represent the most widely used methods for the evaluation of functional properties of solid neoplasms; unlike PET or single photon emission computed tomography, functional imaging techniques applied to conventional MRI/CT examinations do not require the administration of radiolabeled drugs or specific equipments. Moreover, DWI and DCE-MRI can be performed during the same session, thus providing a comprehensive "one-step" morphological and functional evaluation of hepato-bilio-pancreatic tumors. Literature data reveal that functional imaging techniques could be proposed for the evaluation of these tumors before treatment, given that they may improve staging and predict prognosis or clinical outcome. Microscopic changes within neoplastic tissues induced by treatments can be detected and quantified with functional imaging,therefore these techniques could be used also for posttreatment assessment, even at an early stage. The aim of this editorial is to describe possible applications of new functional imaging techniques apart frommolecular imaging to hepatic and pancreatic tumors through a review of up-to-date literature data, with a particular emphasis on pathological correlations,prognostic stratification and post-treatment monitoring.

Advances in application of novel magnetic resonance imaging technologies in liver disease diagnosis

Liver disease is a major health concern globally,with high morbidity and mortality rates.Precise diagnosis and assessment are vital for guiding treatment approaches,predicting outcomes,and improving patient prognosis.Magnetic resonance imaging(MRI)is a non-invasive diagnostic technique that has been widely used for detecting liver disease.Recent advancements in MRI technology,such as diffusion weighted imaging,intravoxel incoherent motion,magnetic resonance elastography,chemical exchange saturation transfer,magnetic resonance spectroscopy,hyperpolarized MR,contrast-enhanced MRI,and radiomics,have significantly improved the accuracy and effectiveness of liver disease diagnosis.This review aims to discuss the progress in new MRI technologies for liver diagnosis.By summarizing current research findings,we aim to provide a comprehensive reference for researchers and clinicians to optimize the use of MRI in liver disease diagnosis and improve patient prognosis.

Hepatobiliary phases in magnetic resonance imaging using liverspecific contrast for focal lesions in clinical practice

BACKGROUND Challenging lesions,difficult to diagnose through non-invasive methods,constitute an important emotional burden for each patient regarding a still uncertain diagnosis(malignant x benign).In addition,from a therapeutic and prognostic point of view,delay in a definitive diagnosis can lead to worse outcomes.One of the main innovative trends currently is the use of molecular and functional methods to diagnosis.Numerous liver-specific contrast agents havebeen developed and studied in recent years to improve the performance of liver magnetic resonance imaging(MRI).More recently,one of the contrast agents introduced in clinical practice is gadoxetic acid(gadoxetate disodium).AIM To demonstrate the value of the hepatobiliary phases using gadoxetic acid in MRI for the characterization of focal liver lesions(FLL)in clinical practice.METHODS Overall,302 Lesions were studied in 136 patients who underwent MRI exams using gadoxetic acid for the assessment of FLL.Two radiologists independently reviewed the MRI exams using four stages,and categorized them on a 6-point scale,from 0(lesion not detected)to 5(definitely malignant).The stages were:stage 1-images without contrast,stage 2-addition of dynamic phases after contrast(analogous to usual extracellular contrasts),stage 3-addition of hepatobiliary phase after 10 min(HBP 10’),stage 4-hepatobiliary phase after 20 min(HBP 20’)in addition to stage 2.RESULTS The interobserver agreement was high(weighted Kappa coefficient:0.81-1)at all stages in the characterization of benign and malignant FLL.The diagnostic weighted accuracy(Az)was 0.80 in stage 1 and was increased to 0.90 in stage 2.Addition of the hepatobiliary phase increased Az to 0.98 in stage 3,which was also 0.98 in stage 4.CONCLUSION The hepatobiliary sequences improve diagnostic accuracy.With growing potential in the era of precision medicine,the improvement and dissemination of the method among medical specialties can bring benefits in the management of patients with FLL that are difficult to diagnose.

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.

Liver volumetric and anatomic assessment in living donor liver transplantation: The role of modern imaging and artificial intelligence

The shortage of deceased donor organs has prompted the development of alternative liver grafts for transplantation.Living-donor liver transplantation(LDLT)has emerged as a viable option,expanding the donor pool and enabling timely transplantation with favorable graft function and improved long-term outcomes.An accurate evaluation of the donor liver’s volumetry(LV)and anatomical study is crucial to ensure adequate future liver remnant,graft volume and precise liver resection.Thus,ensuring donor safety and an appropriate graftto-recipient weight ratio.Manual LV(MLV)using computed tomography has traditionally been considered the gold standard for assessing liver volume.However,the method has been limited by cost,subjectivity,and variability.Automated LV techniques employing advanced segmentation algorithms offer improved reproducibility,reduced variability,and enhanced efficiency compared to manual measurements.However,the accuracy of automated LV requires further investigation.The study provides a comprehensive review of traditional and emerging LV methods,including semi-automated image processing,automated LV techniques,and machine learning-based approaches.Additionally,the study discusses the respective strengths and weaknesses of each of the aforementioned techniques.The use of artificial intelligence(AI)technologies,including machine learning and deep learning,is expected to become a routine part of surgical planning in the near future.The implementation of AI is expected to enable faster and more accurate image study interpretations,improve workflow efficiency,and enhance the safety,speed,and cost-effectiveness of the procedures.Accurate preoperative assessment of the liver plays a crucial role in ensuring safe donor selection and improved outcomes in LDLT.MLV has inherent limitations that have led to the adoption of semi-automated and automated software solutions.Moreover,AI has tremendous potential for LV and segmentation;however,its widespread use is hindered by cost and availability.Therefore,the integration of multiple specialties is necessary to embrace technology and explore its possibilities,ranging from patient counseling to intraoperative decision-making through automation and AI.

Magnetic resonance imaging of portal vein invasion in hepatocellular carcinoma:A corroboration of 25 cases

AIMS Pre-operatively to assess tumor thrombus as- sociated with hepatocellular carcinoma in the portal vein. METHEDS Twenty-five patients diagnosed as hav- ing thrombus due to hepatocellular carcinoma were corroborated. MR imaging was perfomed with a 1.0T superconducting magnetic system. Both T1 and T2 weighed images and FLASH sequences were obtained in transverse plane. Additional FLASH images were ob- tained in coronal plane. RESULTS Thrombus in portal vein had a signal in- tensity similar to that of the main tumors. Intrinsic por- tal vein thrombus was in 16 patients. Six cases showed occlusive thrombus. Diffusely narrow portal branches were found in 3 patients. Portal venous thrombus showed an area of signal intensity which was replacing the normal flow void in the portal vein and showed a stumpy portal vein,irregular stenosis of portal vein and the formation of vascular net. CONCLUSION MRI was more sensitive and specific and a noninvasive method in detection of portal tumor thrombus used jointly with spin ech (SE) and gradient echo (GRE) techniques.

Hepatocellular adenoma: An unsolved diagnostic enigma

Hepatocellular adenoma (HCA) is a rare benign liver tumour associated with the use of oral contraceptives or other steroid medications which occurs predominantly in young and middle-aged women. Unlike other benign liver tumours, an HCA may be complicated by bleeding and malignant transformation. HCAs have been divided into four subtypes based on molecular and pathological features: hepatocyte nuclear factor 1α-mutated HCA, inflammatory HCA,β-catenin-mutated HCA, and unclassified HCA.β-cateninmutated HCA has the highest risk of haemorrhage or malignant transformation. In the latest upgrade of the guidelines regarding the management of benign liver tumours published in 2016 by the European Association for the Study of the Liver, magnetic resonance imaging (MRI) was recognized to be superior to all other imaging modalities in detecting HCAs and in being able to subtype HCAs up to 80%, with positive identification of 1α-mutated HCA or inflammatory HCA achievable with > 90% specificity. This review analyzed the imaging features of HCA using MRI with hepato-specific contrast agents, focusing on the limitations in the HCA characterization.

Performance of common imaging techniques vs serum biomarkers in assessing fibrosis in patients with chronic hepatitis B: A systematic review and meta-analysis

BACKGROUND Noninvasive biomarkers have been developed to predict hepatitis B virus(HBV)related fibrosis owing to the significant limitations of liver biopsy.Both serum biomarkers and imaging techniques have shown promising results and may improve the evaluation of liver fibrosis.However,most of the previous studies focused on the diagnostic effects of various imaging techniques on fibrosis in all chronic liver diseases.AIM To compare the performance of common imaging methods and serum biomarkers for prediction of significant fibrosis caused only by HBV infection.METHODS A systematic review was conducted on the records available in PubMed,EMBASE,and the Cochrane Library electronic databases until December 2018.We systematically assessed the effectiveness of two serum biomarkers and three imagine techniques in predicting significant fibrosis solely caused by HBV infection.The serum biomarkers included aspartate aminotransferase-to-platelet ratio index(APRI)and fibrosis index based on the 4 factors(FIB-4).The three imaging techniques included acoustic radiation force impulse(ARFI),FibroScan,and magnetic resonance elastography(MRE).Three parameters,the area under the summary receiver operating characteristic curve(AUSROC),the summary diagnostic odds ratio,and the summary sensitivity and specificity,were used to examine the accuracy of all tests for liver fibrosis.RESULTS Out of 2831 articles evaluated for eligibility,204 satisfied the predetermined inclusion criteria for this current meta-analysis.Eventually,our final data contained 81 studies.The AUSROCs of serum biomarkers of APRI and FIB-4 were both 0.75.For imaging techniques(ARFI,FibroScan,and MRE),the areas were 0.89,0.83,and 0.97,respectively.The heterogeneities of ARFI and FibroScan were statistically significant(I2>50%).The publication bias was not observed in any of the serum biomarkers or imaging methods.CONCLUSION These five methods have attained an acceptable level of diagnostic accuracy.Imaging techniques,MRE in particular,demonstrate significant advantages in accurately predicting HBV-related significant fibrosis,while serum biomarkers are admissible methods.

Contrast-enhanced multiple-phase imaging features in hepatic epithelioid hemangioendothelioma

AIM： To investigate and review the contrast-enhanced multiple-phase computed tomography （CEMP CT） and magnetic resonance imaging （MRI） findings in patients with pathologically confirmed hepatic epithelioid hemangioendothelioma （HEHE）. METHODS： Findings from imaging examinations in 8 patients （5 women and 3 men） with pathologically confirmed HEHE were retrospectively reviewed （CT images obtained from 7 patients and MR images obtained from 6 patients）. The age of presentation varied from 27 years to 60 years （average age 39.8 years）. RESULTS： There were two types of HEHE： multifocal type （n = 7） and diffuse type （n = 1）. Tn the multifocal-type cases, there were 74 lesions on CT and 28 lesions on MRI with 7 lesions found with diffusion weighted imaging; 18 （24.3%） of 74 lesions on plain CT and 26 （92.9%） of 28 lesions on pre-contrast MRI showed the target sign. On CEMP CT, 28 （37.8%） of 74 lesions appeared with the target sign and a progressive-enhancement rim and 9 （12.2%） of 74 lesions displayed progressive enhancement, maintaining a state of persistent enhancement. On CEMP MRI, 27 （96.4%） of 28 lesions appeared with the target sign with a progressive-enhancement rim and 28 （100%） of 28 lesions displayed progressive-enhancement, maintaining a state of persistent enhancement. In the diffuse-type cases, an enlarged liver was observed with a large nodule appearing with persistent enhancement on CEMP CT and MRI. CONCLUSION： The most important imaging features of HEHE are the target sign and/or progressive en- hancement with persistent enhancement on CEMP CT and MRI. MRI is advantageous over CT in displaying these imaging features.

Comparison of imaging-based and pathological dimensions in pancreatic neuroendocrine tumors

AIM To establish the ability of magnetic resonance(MR) and computer tomography(CT) to predict pathologic dimensions of pancreatic neuroendocrine tumors(Pan NET) in a caseload of a tertiary referral center.METHODS Patients submitted to surgery for Pan NET at the Surgical Unit of the Pancreas Institute with at least 1 preoperative imaging examination(MR or CT scan) from January 2005 to December 2015 were included and data retrospectively collected. Exclusion criteria were: multifocal lesions, genetic syndromes, microadenomas or mixed tumors, metastatic disease and neoadjuvant therapy. Bland-Altman(BA) and Mountain-Plot(MP) statistics were used to compare size measured by each modality with the pathology size. Passing-Bablok(PB) regression analysis was used to check the agreement between MR and CT.RESULTS Our study population consisted of 292 patients. Seventy-nine(27.1%) were functioning Pan NET. The mean biases were 0.17 ± 7.99 mm, 1 ± 8.51 mm and 0.23 ± 9 mm, 1.2 ± 9.8 mm for MR and CT, considering the overall population and the subgroup of non-functioning-Pan NET, respectively. Limits of agreement(LOA) included the vast majority of observations, indicating a good agreement between imaging and pathology. The MP further confirmed this finding and showed that the two methods are unbiased with respect to each other. Considering ≤ 2 cm non-functioning-Pan NET, no statistical significance was found in the size estimation rate of MR and CT(P = 0.433). PBR analysis did not reveal significant differences between MR, CT and pathology.CONCLUSION MR and CT scan are accurate and interchangeable imaging techniques in predicting pathologic dimensions of Pan NET.