Characterization Of Focal Hepatic Lesions Research Articles

MRI Radiomics in Imaging of Focal Hepatic Lesions: A Narrative Review.

Magnetic resonance imaging (MRI) is generally used to identify, describe, and evaluate treatment responses for focal hepatic lesions.However, the diagnosis and differentiation of such lesions require considerable input from radiologists. In order to reduce these difficulties, radiomics is an artificial intelligence (AI)-based quantitative method that employs the extraction of image features to reliably detect and differentiate focal hepatic lesions. MRI radiomics is a novel technique for the characterization of focal hepatic lesions. It can aid in preoperative evaluation, treatment approach, and forecast microvascular invasion. Although many studies have illustrated its efficiency there are certain limitations such as the absence of a large diverse dataset, comparison with other AI models, integration with histopathological findings, clinical utility, and feasibility.

Is Shear Wave Elastography Effective for Characterization of Hepatic Focal Lesions?

Is Shear Wave Elastography Effective for Characterization of Hepatic Focal Lesions?

Utility of diffusion tensor imaging in differentiating benign from malignant hepatic focal lesions.

To assess the diagnostic accuracy of diffusion tensor imaging (DTI) in the characterization of hepatic focal lesions (HFLs) and compare it to diffusion-weighted imaging (DWI). Prospective analysis was done for 49 patients (23 male and 26 female) with 74 HFLs who underwent dynamic MRI, DWI, and DTI. Apparent diffusion coefficient (ADC) values from DWI, fractional anisotropy (FA) values, and mean diffusivity (MD) values from DTI were measured by two independent radiologists. HFLs were classified into benign and malignant HFLs; the latter were subdivided into HCC and non-HCC lesions. Binary logistic regression was performed to analyze the associations between the DTI parameters and the distinction of malignant lesions. The ADC, MD, and FA at cutoff values of ≤ 1.17 × 10-3 mm2/s, ≤ 1.71 × 10-3 mm2/s, and > 0.29, respectively, are excellent discriminators for differentiating malignant and benign HFLs. The mean ADC and MD values of hemangiomas were significantly higher than HCC and non-HCC malignant lesions. In contrast, the mean FA values of hemangiomas were significantly lower than those of non-HCC malignant lesions and HCCs. The ADC and MD were very good discriminators at cutoff values of > 1.03 × 10-3 mm2/s and > 1.12 × 10-3 mm2/s, respectively. The FA at a cutoff value > 0.38 is an excellent discriminator for HCC versus non-HCC malignant lesions. Only FA value > 0.38 was a statistically significant independent predictor of HCC versus non-HCC lesions among the three parameters. There was an excellent inter-observer agreement with ICC > 0.9. MD and FA of DTI are non-invasive, very good, and excellent discriminators superior to ADC measured by DWI for the differentiation of HFLs. • The ADC, MD, and FA at cutoff values of ≤ 1.17 × 10-3 mm2/s, ≤ 1.71 × 10-3 mm2/s, and > 0.29, respectively, are excellent discriminators for differentiating malignant and benign HFLs. • The mean ADC and MD values of hemangiomas were significantly higher than those of HCC and non-HCC malignant lesions. In contrast, the mean FA values of hemangiomas were significantly lower than those of non-HCC malignant lesions and HCCs, respectively. • Multivariate regression analysis revealed that only FA value > 0.38 was a statistically significant independent predictor of HCC vs. non-HCC lesions. A lesion with FA > 0.38 has 34 times higher odds of being HCC rather than non-HCC lesions.

Role of diffusion weighted MRI imaging in characterization of hepatic focal lesions in cirrhotic patients in comparison to dynamic cross sectional imaging

Abstract Aim of work The aim of the study is to show the feasibility of diffusion weighted (DWI) MRI with calculation of the apparent diffusion coefficient in characterization of hepatic focal lesions as well as differentiating benign from malignant lesions in cirrhotic patients. Patients and Methods The study included 35 patients (25 males and 10 females) by cross sectional study and convenient sampling at the Demerdash hospital, inclusion criteria: patients diagnosed by hepatic focal lesions on top of post-viral induced cirrhosis, detected by ultrasound, triphasic CT or dynamic MRI imaging. All patients to be included in the study underwent characterization of hepatic focal lesions to differentiate benign from malignant lesions using a combination of characteristic imaging criteria, including contrast enhancement patterns on MRI. Sequences used were T2 weighted imaging, T2 Spectral Attenuated Inversion Recovery (SPAIR), and diffusion weighted imaging sequences with estimation of the ADC map and calculation of the ADC values. Results Our study was carried on a total of 35 patients including 25 males and 10 female patients having a mean age of 59 ± 10.2 years (58.1 ± 11 and 61.2 ± 8 years for the male and female patients respectively). DWI and ADC showed statistically significant difference among the benign and malignant focal lesions in terms of their diffusion restriction criteria ( P < 0.0001), with a sensitivity, specificity, positive and negative predictive values of 100% (95% CI = 89.5 – 100%), 92.3% (95% CI = 79.6 – 97.3%), 91.6% (95% CI = 78.1 – 97.1%) and 100% (95% CI = 90.3 – 100%), as well as a likelihood ratio of 13. On comparing the ADC values of the focal lesions for the benign and malignant focal lesions, the malignant lesions showed statistically significant lower means as compared to the benign lesions (malignant = 1.08 ± 0.28 x 10-3 mm2/s, benign =2.0 ± 0 x 10-3 mm2/s, P < 0.0001). ROC curve analysis of the ADC values of the benign and malignant focal lesions was highly significant (P < 0.0001), with an area under curve of 0.9745 (97.45% overall accuracy), giving an ADC cut-off value of (< 0.98 x 10-3 mm2/s) for malignant lesions with 97.2% sensitivity (95% CI = 85.83% - 99.86%), 97.2% specificity (95% CI = 85.83% - 99.86%) and a likelihood ratio of 35. Summary and conclusion DWI MRI and the calculation of the ADC are great non invasive possible tools to detect and characterize hepatic focal lesions as well as to differentiate benign from malignant lesions in cirrhotic patients especially in patients with renal impairment and allergy to contrast media also to avoid unnecessary biopsies.

ROLE OF DIFFUSION WEIGHTED MRI IN ASSESSMENT OF BENIGN AND MALIGNANT HEPATIC FOCAL LESIONS IN ADULT AGE GROUP

Abstract Purpose of this study is: To evaluate the role of diffusion weighted magnetic resonance imaging in differentiation between malignant & benign hepatic focal lesions. Methods The study included 38 patients all of them were with hepatic focal lesions detected by ultrasound (between 20 and 85 years of age) referred from GIT and oncology departments. Each patient included in the study was subjected to full history taking, ultrasonography and conventional MRI sequences, post Gd- DTPA dynamic and Diffusion Weighted imaging as well as ADC value measurement. Technique was performed using a standard 1.5 Tesla unit (Ingenia, Philips). Detailed MRI and laboratory investigations were done. Results The study showed significant results were obtained between ADC values of benign and malignant hepatic focal lesions (p < 0.001). Conclusion We concluded in this study according to the obtained results that DWI sequence together with quantitative ADC values should be used as an essential sequence to supplement the conventional MRI sequences for proper detection and characterization of hepatic focal lesions.

Characterization of Hepatic Focal Lesions by Diffusion Tensor Imaging and How Far it Can Predict Post-Treatment Response?

Abstract Background: Liver diseases have been known to be a major health problem principally because of their world-wide distribution. Focal liver disease is a common diagnostic problem referred to radiologists for evaluation owing to its nonspecific clinical presentation and marked interobserver variation on clinical examination. Aim of Study: The purpose of this study is to evaluate the role of diffusion tensor imaging in characterization of hepatic focal lesions and its value in post-treatment response. Patients and Methods: This prospective study included 30 patients previously diagnosed to have hepatic focal lesions (HFLs) by their characteristic triphasic computed tomography (CT), dynamic magnetic resonance imaging (MRI) features and/or biopsy. The study included 43 lesions in 30 patients (16 benign lesions, 23 malignant lesions, and 4 treated malig-nant lesions). MRI with diffusion tensor imaging (DTI) was performed for all patients. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were evaluated for all lesions. Results: There was a statistically significant difference in ADC values between the benign and malignant lesions (p 1.42x 10-3 mm2/s with 95.7% sensitivity and 82.8% specificity. The best cut-off ADC value to differ-entiate between treated malignant and malignant lesions respectively was >1.65x 10-3 mm2/s with 97.8% sensitivity and 95.7% specificity. The best cut-off FA value to differentiate between malignant and benign lesions respectively was >0.29 with 95% sensitivity and 70% specificity. The best cut-off FA value to differentiate between treated malignant and untreated malignant lesions respectively was <0.297 with 100% sensitivity and 69.2% specificity. Conclusion: Diffusion tensor imaging is an evolving technique that can be used to characterize different hepatic focal lesions either benign or malignant with significant additive value to dynamic contrast enhanced MRI examination. It can also be used to monitor treatment response.

Role of Diffusion-Weighted Magnetic Resonance Imaging inDetecting and Characterizing Benign and Malignant LiverTumors in Adults

AbstractBackground: DWI is done by quantifying the amount ofdiffusion through tissues and calculating ADC values. Tumors,which consist of excessive proliferation of cells, wouldexpectantly show restricted diffusion. ADC values can aid incharacterizing focal liver lesions as benign vs. malignant.DWI when used in combination with dynamic MRI can beused to enhance the accuracy of liver lesion characterizationand diagnosis.Aim of Study: To assess the role of diffusion-weightedmagnetic resonance imaging (DWI) in detection and charac-terization of hepatic focal lesions, and its value in differenti-ating benign from malignant masses.Patients and Methods: A total of 60 liver disease patients (21 males and 39 females) with ages ranged from 20 to 63years old were included in the study. All of the patientsunderwent MRI examination including pre-contrast imaging,dynamic study and diffusion study. The morphological featuresof each lesion were recorded and diffusion images werereviewed for final radiological characterization and detection of focal lesions. ADC values were calculated for all patients.Results: This study included 60 patients with varioustypes of lesions, 40 of which had benign lesions and 20 withmalignant lesions. The diffusion images aided in diagnosisof malignant lesions with different components. AbsoluteADC values of different types of lesions were not similar.Benign hepatic lesions have generally higher ADC valuescompared with malignant lesions. The ADC values we foundfor different lesions were consistent with previous studies.Conclusion: Diffusion-weighted MRI sequence withquantitative ADC measurement should be used as an additionalsequence to supplement conventional MRI protocol studiesfor proper detection and characterization of solid liver lesions.

Characterization of focal liver lesions using sulphur hexafluoride (SF6) microbubble contrast-enhanced ultrasonography

BackgroundFocal hepatic lesions incidentally detected during ultrasound usually need further step for proper characterization. The aim of this study was to highlight the efficacy of microbubble contrast-enhanced ultrasonography (CEUS) in characterization of focal liver lesions. This prospective study was conducted on 60 patients presented with hepatic focal lesions in the period from January 2019 to June 2020. CEUS studies were performed after a baseline conventional ultrasound with the same machine by the same operator. The ultrasound contrast agent used is second-generation US contrast agent. The enhancement patterns of the hepatic lesions were studied during the vascular phases up to 5 min and the data were correlated with histopathology, triphasic contrast-enhanced CT, and clinical follow-up.ResultsCEUS demonstrated a sensitivity of 94.2%, specificity of 88.9%, positive predictive value of 91%, negative predictive value of 94.1%, and accuracy of 92.3% for characterization of hepatic focal lesions, compared to a sensitivity of 100%, specificity of 81.8%, positive predictive value of 84%, negative predictive value of 100%, and accuracy of 90.7% for triphasic CT.ConclusionCEUS is an effective tool in characterization of HFLs and recommended as a second diagnostic step after conventional ultrasound to immediately establish the diagnosis especially in patients with contraindications to CECT.

Apparent diffusion coefficient for differentiating between benign and malignant hepatic focal lesions

BackgroundThe aim of this study was to prospectively evaluate the role of diffusion weight MRI (DWI) in the characterization of hepatic focal lesions by using apparent diffusion coefficient (ADC). Thirty patients (18 women, 12 men; mean age 48.5 years) with hepatic focal lesions were included in this study. Patients underwent DW MR imaging with the SPLICE sequence. ADC of each focal lesion carcinoma was calculated from DW MR Images obtained with low and high b values. ADCs were compared among pathological types of focal lesions.ResultsAmong the 30 patients included in the study, 46 focal lesions were detected. Twenty-four lesions were metastatic lesions from primary cancer, 7 lesions were hepatocellular carcinoma (HCC), 9 lesions were hemangiomas, and 6 lesions were simple cysts. There was highly significant difference between the mean ADC of the malignant lesions (metastasis and HCC) and the mean ADC of benign lesions (hemangiomas and cysts). The ADC of malignant lesion was much less than that of benign lesion. The mean ADC of malignant lesions (n = 31) was 0.73 ± 0.19 × 10−3 mm2/s, and the mean ADC of benign lesions (n = 15) was 1.94 ± 0.68 × 10−3 mm2/s (p value < 0.001). There was no significant difference between the cysts and hemangiomas. There was no statistically significant difference between the metastases and hepatocellular carcinoma.ConclusionADCs values were able to differentiate benign from malignant lesions. ADC should be considered in the work up of patients with hepatic focal lesions.

Role of shear wave sono-elastography (SWE) in characterization of hepatic focal lesions

BackgroundFocal liver lesions are considered a major problem during abdominal examinations. Shear wave sono-elastography (SWE) has been demonstrated to be helpful in assessment of liver fibrosis degree.The purpose of this study was to evaluate the role of SWE in characterization of benign and malignant hepatic focal lesions.ResultsSeventy-five (75) patients with variable focal liver lesions (52 malignant and 23 benign) were analyzed by SWE. The stiffness values of surrounding hepatic parenchyma were also measured as a reference for readings of the focal lesion stiffness values. Final diagnosis was achieved by core needle biopsy (in 1 benign and 38 malignant cases) and contrast enhanced CT and MRI (in all cases).Cholangiocarcinoma (CCC) was the stiffest malignant lesion with median stiffness value (35.9 kPa). Focal nodular hyperplasia (FNH) was the stiffest benign lesion (26.7 kPa).The median stiffness value of malignant focal lesions (20.22 kPa) was significantly higher than that of benign focal lesions (10.68 kPa) (P value < 0.001).ROC curve of SWE median stiffness values for differentiation of benign from malignant hepatic focal lesions had AUC = 0.834, and using cut of value 14.165 kPa, yielding 98.1% sensitivity, 78.3% specificity, and 92% accuracy.ConclusionSWE has high accuracy in differentiating benign form malignant liver focal lesions with promising results in individual characterization of some malignant (HCC and CCC) and benign hepatic focal lesion (FNH from other benign lesions).

Role of shear wave elastography in characterization of hepatic focal lesions

BackgroundElastography is a recently developed diagnostic method that aims to evaluate tissue stiffness. Its utility is based on the fact that pathological tissues are generally stiffer than surrounding healthy tissues which often show up as a hard lesion. Shear wave elastography (SWE) is a new technique based on shear waves that has been implemented in diagnostic ultrasound (US) systems. The aim of this study is to study the role of shear wave elastography in differentiation between benign and malignant hepatic focal lesions.ResultsThe study was conducted on 110 patients (92 males, 18 females) with a mean age of 51.7 years. Age range was from 30 to 70 years; 28 patients were diagnosed with benign lesions, and 82 with malignant lesions. SWE shows that there is a significant difference in stiffness between malignant and benign lesions with p value = 0.002 and with mean ± SD of 10.3 ± 6.31 kPa for the benign lesions and 16.2 ± 9.32 kPa for the malignant group. A cutoff value of 13.24 was selected to differentiate between benign and malignant lesions using the SWE mean providing sensitivity 78.04%, specificity 71.42%, and accuracy 64.2%.ConclusionSWE is a good tool in the differentiation of benign and malignant hepatic focal lesions.

Diagnostic value of the gradient-echo in-phase and out-of-phase MRI sequence in the characterization of benign and malignant hepatic focal lesions

Background MRI is an excellent imaging modality to evaluate the liver which is vulnerable to a spectrum of neoplastic and nonneoplastic conditions. Out-of-phase T1 weighted (T1W) gradient-echo imaging is a highly accurate technique to distinguish focal hepatic steatosis from neoplastic masses. Aim This study aimed to demonstrate the diagnostic value of gradient-echo in-phase and out-of-phase MRI sequence in the characterization of benign and malignant hepatic focal lesions. Patients and methods This study is carried out on 89 patients with 100 hepatic focal lesions; their ages ranged from 32 to 76 years (mean, ±52 years), who traveled for MRI liver for the diagnosis and characterization of hepatic focal lesions. MR examination was performed including T1WI, T2WI, postcontrast dynamic enhanced T1WI followed by gradient-echo in-/out-of-phase MRI sequences. Results The 100 hepatic focal lesions proved to be: 17 focal fatty infiltration, one lipoma and eight fatty-spared area (FSA), 11 hemangioma, 10 regenerative cirrhotic nodules (RN), eight siderotic liver nodules, 12 dysplastic liver nodules, 23 hepatocellular carcinomas, seven metastatic, and three lymphoma. At conventional MRI, most of the benign hepatic focal lesions exhibit iso/hyperintense signals at T1WI and iso/hypointensity at T2WI. However, nearly all malignant lesions exhibit mainly hypointense signals at T1WI and mild hyperintensity at T2WI. At DCE T1WI: focal fatty infiltration and FSA, RN, and siderotic liver nodules take no enhancement; hemangiomas showed marginal arterial enhancement with gradual filling and there is arterial contrast enhancement with venous washout in hepatocellular carcinomas and arterial enhancement with or without washout in metastatic lesions; however, lymphomatous lesions showed temporary perilesional arterial enhancement with delayed contrast enhancement. The gradient in-/out-of-phase sequence: accurately diagnoses the all fat-containing lesions that showed moderate hyperintensity in the in-phase images and signal loss in out-of-phase images, while FSA exhibit in-phase isointensity and hyperintensity in out-of-phase images while all other benign and malignant hepatic focal lesions revealed hypointense signals in both in-/out-of-phase images. Conclusion Gradient-echo in-/out-of-phase sequence is a simple and noninvasive method that can aid in the diagnosis and characterization of benign and malignant hepatic focal lesions with 100% accuracy in the diagnosis of fat-containing lesions. Also, it can differentiate RN from dysplastic liver nodules that is considered as premalignant lesions and improve the malignant hepatic focal lesion definition.

Does MRI diffusion help in the detection and characterization of benign and malignant hepatic focal lesions in the nonpediatric age group?

Introduction Liver MRI has been used in cases where ultrasound or computed tomography findings are equivocal. Diffusion-weighted imaging (DWI) established an important role in clinical use in the liver. DWI can potentially add useful information to conventional imaging. Objective The aim was to assess the role of DWI in the detection and characterization of hepatic focal lesions and its value to differentiate benign from malignant masses. Patients and methods The study included 40 patients, 19 women and 21 men, their ages ranged from 20 to 63 years. All patients underwent detailed MRI study of the abdomen. Diffusion study was performed with tridirectional diffusion gradients using b values 0, 500, and 1000 s/mm2 to increase the sensitivity. Apparent diffusion coefficient (ADC) maps and values were calculated for all lesions. Results In all, 20 patients were diagnosed to have benign lesions and 20 patients were diagnosed to have malignant lesions. Hemangiomas and cysts showed facilitated diffusion while adenomas show restricted diffusion pattern mimicking malignant focal lesions. On the other hand, all malignant lesions showed restricted diffusion evidenced by increased signal on increasing the b values and low signal on ADC maps. Mostly benign lesions show higher ADC values than malignant lesions. Conclusion Diffusion-weighted MRI sequence with quantitative ADC measurements should be used as an additional sequence to supplement conventional MRI protocol studies for proper characterization of focal hepatic lesions putting into consideration an overlap range.

Usefulness of Ultrasound in Characterization of Focal Hepatic Lesions

Usefulness of Ultrasound in Characterization of Focal Hepatic Lesions

Sonazoid-Enhanced Ultrasonography Guidance Improves the Quality of Pathological Diagnosis in the Biopsy of Focal Hepatic Lesions

Contrast-enhanced ultrasonography (US) using second-generation contrast agent Sonazoid has improved the detection and characterization of focal hepatic lesions. We evaluated the utility of Sonazoid-enhanced ultrasonography (SEUS) in guiding percutaneous biopsy of focal hepatic lesions by comparing accuracy of histopathological diagnosis between B-mode US and SEUS guidance. This retrospective study included 140 focal hepatic lesions in 127 patients (mean age; 63.6 years) referred for US-guided percutaneous biopsy between April 2012 and September 2016. The diagnostic accuracy of the biopsy was defined as the percentage of the total number of lesions clearly diagnosed at the initial biopsy. A case was considered a technical failure when pathological results failed to specifically indicate final diagnosis owing to insufficient material or when pathological results changed from benign to malignant by re-biopsy. Among 140 focal hepatic lesions, 57 lesions underwent biopsy with B-mode US guidance while 83 received SEUS guidance. Patient characteristics (sex, age, lesion location and diameter, and reasons for biopsy) did not differ significantly between groups. Diagnostic accuracy was significantly higher under SEUS guidance than B-mode US guidance (91.6% vs. 75.4%, respectively; p < 0.05). When biopsies were performed to diagnose or rule out malignancy in indeterminate focal hepatic lesions, diagnostic accuracy was also significantly higher under SEUS guidance than B-mode US guidance (100% vs. 70.8%, respectively; p < 0.05). SEUS guidance resulted in a significantly higher rate of successful single-puncture attempts during biopsy procedures than B-mode US guidance (53.0% vs. 35.1%, respectively; p < 0.05). SEUS guidance improves the accuracy of hepatic tumor biopsy pathological diagnosis compared to B-mode US guidance. SEUS guidance is recommended for more accurate localization of suitable hepatic lesion biopsy areas since it increases conspicuity and differentiates viable area from denaturalization or necrosis.

Hepatocyte-specific contrast agent-enhanced magnetic resonance cholangiography: perioperative evaluation of the biliary tree.

A large number of gadolinium chelates have recently been tested in clinical trials. Some of those have already been approved for clinical use in the United States and Europe. Thus, new diagnostic perspectives have been incorporated into magnetic resonance imaging studies. Among such gadolinium chelates are hepatobiliary-specific contrast agents (HSCAs), which, due to their property of being selectively taken up by hepatocytes and excreted by the biliary ducts, have been widely used for the detection and characterization of focal hepatic lesions. In comparison with conventional magnetic resonance cholangiography (MRC), HSCA-enhanced MRC provides additional information, with higher spatial resolution and better anatomic evaluation of a non-dilated biliary tree. A thorough anatomic assessment of the biliary tree is crucial in various hepatic surgical procedures, such as complex resection in patients with colorectal cancer and living-donor liver transplantation. However, the use of HSCA-enhanced MRC is still limited, because of a lack of data in the literature and the poor familiarity of radiologists regarding its main indications. This pictorial essay aims to demonstrate the use of HSCA-enhanced MRC, with particular emphasis on anatomical analysis of the biliary tree, clinical applications, and the most important imaging findings.

Sonazoid-enhanced ultrasonography guidance improves the quality of pathological diagnosis in the biopsy of focal hepatic lesions

Contrast-enhanced ultrasonography (US) has improved the detection and characterization of focal hepatic lesions. Recently, the importance of obtaining high-quality samples in the biopsy of hepatic lesions has been increasing not only in the field of pathological diagnosis but also in molecular analysis for predicting the effectiveness of anticancer agents and molecular targeted drugs. We evaluated the utility of Sonazoid-enhanced ultrasonography (SEUS) in guiding percutaneous biopsy of focal hepatic lesions by comparing the results of histopathological diagnosis between B-mode US and SEUS guidance. This retrospective study examined 121 focal hepatic lesions in 108 patients (mean age: 63.8 years) referred for US-guided percutaneous biopsy. The technical success rate was defined as the percentage of the lesions diagnosed clearly at the initial biopsy. Among 121 lesions, 56 lesions were subjected to biopsy with B-mode US guidance whereas 65 were subjected to SEUS guidance. The technical success rate was significantly higher under SEUS guidance than under B-mode US guidance (92.3 vs. 76.8%, respectively, P<0.05). When biopsies were performed to diagnose or rule out malignancy in indeterminate lesions, the technical success rate was also significantly higher under SEUS guidance than under B-mode US guidance (100 vs. 73.9%, respectively, P<0.05). SEUS guidance resulted in a significantly higher rate of successful single-puncture attempts compared with B-mode US guidance (55.4 vs. 35.7%, respectively, P<0.05). SEUS guidance is recommended for more accurate localization of suitable hepatic lesion biopsy areas as it increases conspicuity and differentiates viable areas from denaturalization or necrosis.

Liver-specific magnetic resonance contrast medium in the evaluation of chronic liver disease.

ABSTRACTThe hepatobiliary-specific contrast medium (gadoxetic acid – Primovist®) is primarily used to improve detection and characterization of focal hepatic lesions, such as in chronic liver disease patients with suspected hepatocellular carcinoma. Since the contrast medium is selectively taken up by functioning hepatocytes in the late hepatobiliary phase, it helps to detect typical hepatocellular carcinoma, which show low signal intensity on this phase. This imaging feature also assists in differentiating regenerative/dysplastic nodules from early hepatocellular carcinomas (with over 90% accuracy), as well as hypervascular hepatocellular carcinomas from arterial pseudo-enhancement foci. Future perspectives include its use in quantification of hepatic function and fibrosis.

The added value of PET/Ce-CT/DW-MRI fusion in assessment of hepatic focal lesions: PET/Ce-CT/DW-MRI fusion in hepatic focal lesion

IntroductionThe liver hosts a variety of benign and malignant tumors. Accurate diagnosis can be challenging in certain cases, especially in patients with a history of malignancy or in those with underlying liver pathology, such as cirrhosis. ObjectivesTo evaluate the added clinical value of multi-modality liver imaging utilizing PET/Ce-CT/DW-MRI for characterization of hepatic focal lesions (HFL) and compare it with each diagnostic modality when interpreted alone. MethodsThe study included 35 patients with HFL. They were 7 females & 28 males; their age ranged from 41 to 78years, all patients underwent PET/Ce-CT and DW-MRI scans. Ce-CT, PET and DW-MR images were reviewed independently, and then combined PET/Ce-CT, PET/DW-MRI and PET/Ce-CT/DW-MRI scans were analyzed. The results were correlated with histopathology or clinical/imaging follow-up. ResultsThe 35 patients had 98 focal lesions. Fifty-three lesions were finally diagnosed as primary hepatocellular carcinoma, 18 lesions were metastases, 7 lesions were lymphoma and 20 lesions were benign. On a patient based analysis; the sensitivity, specificity, PPV, NPV and accuracy were 100%, 67%, 94%, 100% and 94% for PET/Ce-CT compared to 97%, 83%, 97%, 83% and 94 % for DW-MRI, respectively. Combined PET/Ce-CT/DW-MR scans raise those parameters up to 100%. On a lesion based analysis; the sensitivity, specificity, PPV, NPV and accuracy were 94%, 75%, 94%, 75%, 90% for PET/Ce-CT compared to 94%, 95%, 99%, 97% and 94 % for DW-MRI, respectively. All these parameters were 100 % with PET/Ce-CT/DW-MRI. ConclusionsThe addition of DW-MRI to PET/Ce-CT is valuable in the characterization of hepatic focal lesions.

Superparamagnetic iron oxide-enhanced magnetic resonance imaging for focal hepatic lesions: systematic review and meta-analysis.

To evaluate the performance of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) in the detection and characterization of focal hepatic lesions (FHLs). This meta-analysis compared relevant studies that were identified by searching PubMed, EMBASE, and the Cochrane Library databases for articles published between January 1988 and September 2014 and that met the following criteria: (1) SPIO-enhanced MRI was conducted to identify FHLs and data were sufficient for pooled analysis using Meta-DiSc 1.4; (2) hepatocellular carcinomas (HCCs) were differentiated from other FHLs; (3) well-differentiated HCCs (WD-HCCs) were contradistinguished from dysplastic nodules; and (4) WD-HCCs were compared with moderately and poorly differentiated HCCs (MD- and PD-HCCs, respectively). The data obtained from 15 eligible studies yielded a sensitivity of 85% and a specificity of 78% for differentiating between HCCs and other FHLs. The sensitivity was unchanged and the specificity was increased to 87% when non-HCC malignancies were excluded. Comparative analyses between WD-HCCs and MD- and PD-HCCs from seven studies showed a sensitivity of 98% and a specificity of 50% for the diagnosis of MD- and PD-HCCs, and the area under the summary receiver operating characteristics (sROC) curve was 0.97. A comparison between WD-HCCs and dysplastic nodules revealed a sensitivity of 50% and a specificity of 92% for the diagnosis of WD-HCCs and the area under the sROC curve was 0.80. SPIO-enhanced MRI is useful in differentiating between HCCs and other FHLs.