Characterization Of Hepatic Lesions Research Articles

TRIPLE PHASE CT EVALUATION OF LIVER LESIONS WITH FNAC/HPE CORRELATION.

Introduction: Detection and characterization of hepatic lesions is crucial due to the high prevalence of both benign and malignant lesions. USG is the most common initial method for evaluation, but in most cases, a definitive diagnosis cannot be made based on it. CT is superior modality because of its ability to detect vascular perfusion in the different phases. Aim: Objectives: To assess the role of Triple phase computed tomography in differentiating various focal hepatic SOLs. To evaluate the characteristics of focal hepatic lesions on a Triphasic Computed Tomography scan performed in patients with suspected focal liver disease and to correlate the CT findings with FNAC/Histopathological examination. Methodology: This prospective study was conducted for a period of one year. 90 patients were included with suspected hepatic lesions clinically or on ultrasound findings with age more than seven years from both genders. Computed tomography (CT) examinations were done and different enhancement patterns were then seen. The final report was made by the radiologist while the FNAC/HPE findings were reviewed. In present study, 56% of patient Results: s were males and 44% were females. Right lobe was involved in 60% and both lobes in 23% of patients. The most common lesion was hemangioma. Abscess was the 2nd most common benign lesion. Sensitivity, specificity, PPV and NPV for HCC detection was 85%, 95%, 81.8% and 92.7% respectively. Sensitivity, specificity, PPV and NPV for metastasis detection was 85%, 84.37%, 77.3% and 90% respectively. Triple phase CT not only diagnosed hepatic lesions wi Conclusion: th high sensitivity and specificity but also helped in planning the management. CT findings very well correlated with the final pathological diagnosis.

Gadoxetic acid (Primovist®) beyond the characterization of hepatic lesions in MRI: the case of biliary leaks.

Gadoxetic acid (Primovist®) is a paramagnetic contrast agent widely known for its use in the characterisation of focal liver lesions; however, it is also an important tool for the evaluation of the biliary tract. Its hepatospecific properties are able to demonstrate the presence and location of biliary leaks by MRI, allowing appropriate treatment planning and avoiding unnecessary invasive tests.

ROLE OF TRIPLE PHASE CONTRAST ENHANCED COMPUTED TOMOGRAPHY IN HEPATIC LESIONS AND THEIR CYTOPATHOLOGICAL CORRELATION

AIMS: To evaluate the enhancement patterns of hepatic lesions on triple phase contrast enhanced computed tomography and to correlate the CT ndings of hepatic lesions with cytological ndings on ne needle aspiration cytology (FNAC). Settings and Design: This prospective observational study was carried out at Department of Radiodiagnosis, Gobind Singh Medical College and Hospital, Faridkot. The study was approved by the Institutional Ethics Committee. Source of Data: A total of 75 patients who had hepatic lesions on ultrasonography and clinical suspicion of focal hepatic lesions were referred for CECT abdomen. Findings of Triple phase CT for hepatic lesions were correlated with cytopathological ndings. Methods and Material: A Triphasic CECT abdomen was performed on Siemens Somatom Perspective 128 slice scanner in the Department of Radiodiagnosis, Guru Gobind Singh Medical College and Hospital, Faridkot. The entire liver was scanned successively, in arterial, portovenous and delayed phases. A 5mm collimation and 5mm/sec table speed were used. After obtaining a digital scout view, unenhanced scan of the liver was obtained.1.5ml/kg body weight of 300mgI/ml iodinated contrast material was administered by using a pressure injector at a rate of 3.0 mL/s using a pressure injector.USG/CT guided FNAC was done. CT imaging ndings were classied as benign or malignant by correlating them with cytopathological ndings. Results: The present study inferred that Triple phase CECT is a highly sensitive and specic imaging modality for detection and characterization of hepatic lesions with an overall sensitivity and specicity of 100.00 % (95% C.I. 92.45% to 100%) and 92.86% (95% C.I. 76.50% to 99.12%)respectively when correlated with cytopathological ndings. Conclusions: It is inferred from our study that triple phase CECT is highly sensitive and specic imaging modality for detection and characterization of hepatic lesions with wide availability in the present scenario.

Role of Diffusion-Weighted Magnetic Resonance Imaging in the Diagnosis of Hepatic Focal Lesions

Background: Diffusion-weighted imaging (DWI) is a novel imaging technique with a growing application in oncoimaging. This modality evaluates the diffusion of water molecules in various tissues, which is restricted in hypercellular regions such as malignant tissue. Apparent diffusion coefficient (ADC) is a method that can quantify the degree of restriction in tissues and can have diagnostic roles in the characterization of hepatic lesions. Aim of the Work: To study the role of diffusion-weighted MRI sequence with quantitative ADC measurements as a useful tool in the differentiation between benign and malignant liver lesions. Patients and Methods: The current study was carried out on thirty adult patients, 24 males (80%), and 6 females (20%). They were presented to Qena University Hospitals at the Radiodiagnosis Department. Results: Both, qualitative evaluation of high b-value DW-MR images and quantitative evaluation of ADC maps are employed for lesion characterization. The ADC values of benign lesions are significantly higher than those of malignant lesions, with variable degrees of overlap between the pathological entities. Conclusion: DW MR imaging has the potential to be a reasonable alternative technique to contrast-enhanced imaging.

Role of Diffusion-Weighted Magnetic Resonance Imaging in the Diagnosis of Hepatic Focal Lesions

Background: Diffusion-weighted imaging (DWI) is a novel imaging technique with a growing application in oncoimaging. This modality evaluates the diffusion of water molecules in various tissues, which is restricted in hypercellular regions such as malignant tissue. Apparent diffusion coefficient (ADC) is a method that can quantify the degree of restriction in tissues and can have diagnostic roles in the characterization of hepatic lesions. Aim of the Work: To study the role of diffusion-weighted MRI sequence with quantitative ADC measurements as a useful tool in the differentiation between benign and malignant liver lesions. Patients and Methods: The current study was carried out on thirty adult patients, 24 males (80%), and 6 females (20%). They were presented to Qena University Hospitals at the Radiodiagnosis Department. Results: Both, qualitative evaluation of high b-value DW-MR images and quantitative evaluation of ADC maps are employed for lesion characterization. The ADC values of benign lesions are significantly higher than those of malignant lesions, with variable degrees of overlap between the pathological entities. Conclusion: DW MR imaging has the potential to be a reasonable alternative technique to contrast-enhanced imaging.

The diagnostic value of diffusion-weighted imaging in differentiating benign from malignant hepatic lesions

BackgroundDiffusion-weighted imaging (DWI) is a novel imaging technique with growing application in onco-imaging. This modality evaluates the diffusion of water molecules in various tissues, which is restricted in hyper cellular regions such as malignant tissue. Apparent diffusion co-efficient (ADC) is a method which can quantify the degree of restriction in tissues and can have diagnostic roles in characterization of hepatic lesions. In this study, 93 patients with proven hepatic lesions were included. These patients had undergone initial evaluation via ultrasonography and dynamic CT scan, and had a definite diagnosis confirmed by biopsy. These patients underwent DW imaging and ADC values of their lesions were calculated. Patients were divided into two groups, benign and malignant groups, based on their biopsy results; and ADC values of hepatic lesions were compared in the two groups.ResultsThe two groups were gender matched. There was a significant difference in the age distribution between the two groups. Mean ADC values for benign and malignant hepatic lesions were 1.58 ± 0.35 (10-3 mm2/s) and 0.87 ± 0.16 (10-3 mm2/s), respectively. There was a statistically significant differences between benign and malignant hepatic lesions (p value < 10-3). DW imaging had a sensitivity of 97.6% and specificity of 98.7% in detecting malignant hepatic lesions from benign ones (p = 0.0001, AUC = 0.99).ConclusionDW MRI imaging can differentiate malignant and benign liver lesions with high sensitivity and specificity using ADC values generated; furthermore, each subgroup of hepatic lesions could be determined based on ADC values.

Intravenous gadolinium-based hepatocyte-specific contrast agents (HSCAs) for contrast-enhanced liver magnetic resonance imaging in pediatric patients: what the radiologist should know.

Hepatocyte-specific contrast agents (HSCAs) are a group of intravenous gadolinium-based MRI contrast agents that can be used to characterize hepatobiliary pathology. The mechanism by which these agents are taken up by hepatocytes and partially excreted into the biliary tree improves characterization of hepatic lesions and biliary abnormalities relative to conventional extracellular gadolinium-based contrast agents (GBCAs). This manuscript presents an overview of HSCA use in pediatric patients with the intent to provide radiologists a guide for clinical use. We review available HSCAs and discuss dosing and age specifications for use in children. We also review various hepatic and biliary indications for HSCA use in children, with emphasis on the imaging characteristics distinct to HSCAs, as well as discussion of pitfalls one can encounter when imaging with HSCAs. Given the growing concern regarding gadolinium deposition in soft tissues and brain, we also discuss safety of HSCA use in children.

Intraindividual Comparison between Gadoxetate-Enhanced Magnetic Resonance Imaging and Dynamic Computed Tomography for Characterizing Focal Hepatic Lesions: A Multicenter, Multireader Study

ObjectiveTo compare the diagnostic accuracy of dynamic computed tomography (CT) and gadoxetate-enhanced magnetic resonance imaging (MRI) for characterization of hepatic lesions by using the Liver Imaging Reporting and Data System (LI-RADS) in a multicenter, off-site evaluation.Materials and MethodsIn this retrospective multicenter study, we evaluated 231 hepatic lesions (114 hepatocellular carcinomas [HCCs], 58 non-HCC malignancies, and 59 benign lesions) confirmed histologically in 217 patients with chronic liver disease who underwent both gadoxetate-enhanced MRI and dynamic CT at one of five tertiary hospitals. Four radiologists at different institutes independently reviewed all MR images first and the CT images 4 weeks later. They evaluated the major and ancillary imaging features and categorized each hepatic lesion according to the LI-RADS v2014. Diagnostic performance was calculated and compared using generalized estimating equations.ResultsMRI showed higher sensitivity and accuracy than CT for diagnosing hepatic malignancies; the pooled sensitivities, specificities, and accuracies for categorizing LR-5/5V/M were 59.0% vs. 72.4% (CT vs. MRI; p < 0.001), 83.5% vs. 83.9% (p = 0.906), and 65.3% vs. 75.3% (p < 0.001), respectively. CT and MRI showed comparable capabilities for differentiating between HCC and other malignancies, with pooled accuracies of 79.9% and 82.4% for categorizing LR-M, respectively (p = 0.139).ConclusionGadoxetate-enhanced MRI showed superior accuracy for categorizing LR-5/5V/M in hepatic malignancies in comparison with dynamic CT. Both modalities had comparable accuracies for distinguishing other malignancies from HCC.

Enhancements in hepatobiliary imaging: the spectrum of gadolinium-ethoxybenzyl diethylenetriaminepentaacetic acid usages in hepatobiliary magnetic resonance imaging.

Gadolinium-ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) is a unique hepatocyte-specific contrast agent approved for clinical use in the United States in 2008. Gd-EOB-DTPA-enhanced MR has shown to improve detection and characterization of hepatic lesions. Gd-EOB-DTPA is now being routinely used in daily clinical practice worldwide. Therefore, it is important for radiologists to be familiar with the potential uses and pitfalls of Gd-EOB-DTPA, which extends beyond the assessment of focal hepatic lesions. The purpose of this article is to review the various usages of Gd-EOB-DTPA in hepatobiliary MR imaging.

513 Prognostic Value of Hepatic Margin Status After Resection of Colorectal Liver Metastases After Preoperative Chemotherapy

Objective: MRI has been shown to be more accurate than CT in the diagnoses and characterization of hepatic lesions. However, it is unclear how MRI affects surgical decision making. The objective of this study is to identify the effect of MRI on clinical management of hepatic lesions after initial CT evaluation. Methods: A retrospective review of a prospective liver database between 2004 and 2013 was performed and a total of 102 cases in 101 patients were identified that underwent CT followed by MRI within 30 days to characterize hepatic lesions being evaluated for surgical treatment. The findings between CT and MRI were compared to identify differences in location, size, number and characterization of hepatic lesions. Diagnoses were confirmed by operative findings/pathology and follow up on imaging. The effect of MRI on management was classified into three categories: 1) No change from CT, 2) Diagnostic clarification leading to no surgery (A: unresectable, B: no indication for surgery, C: change in non-surgical treatment), and 3) Change in extent of surgical resection (A: larger resection, B: smaller resection) Results: In the 102 cases, the major tumor histology groups were as follows: benign [9 (9%)], colorectal metastases [47 (46%)], HCC/cholangiocarcinoma [26 (25%)], neuroendocrine metastases [12 (12%)], and other [8 (8%)]. Category 1 had 57 cases (56%), category 2 had 19 cases (19%), and category 3 had 26 cases (25%). Of the 19 category 2 cases, there were eight 2A, nine 2B and two 2C cases. Of the 26 category 3 cases, there were fifteen 3A cases and eleven 3B cases. The number of tumors on CT [Mean 1.6 (category 1) vs. 2.4 (categories 2 and 3), p=0.0034] was significantly associated with MRI imaging leading to a change in management. The maximum tumor size on CT [Mean 4.0 (category 1) vs. 2.7 (category 2 and 3), p=0.0714] suggested a trend towards MRI having an effect on surgical management. Factors such as age, gender, BMI, cirrhosis, prior chemotherapy, tumor histology, vascular invasion on CT, and tumor location on CT were not significantly associated with MRI category 2 or 3. Conclusion: The use of MRI in the surgical evaluation of hepatic lesions after initial CT scan changed management in 44% of cases. Multiple lesions and smaller lesions seen on CT may derive the most benefit from application of MRI imaging.

Improvement of Hepatic Lesion Characterization by 18F-FDG PET/CT with the Use of the Lesion to Background Liver Activity Ratio

This study aimed to develop a reproducible method to improve (18)F-FDG PET/CT's diagnostic accuracy when characterizing hepatic lesions. This was a retrospective study of 76 patients with various types of cancer who had 134 liver lesions described on diagnostic CT, MRI, or (18)F-FDG PET/CT. All 134 lesions were imaged by PET/CT. For comparison, all 134 lesions were also imaged either by MRI (58 lesions) or by diagnostic CT (107), with some imaged by both. The original reader's interpretation was used to determine the diagnostic validity of each modality. The (18)F-FDG PET/CT findings were then re-stratified using the ratio of the SUV(max) of the liver lesion to the SUV(avg) of liver background (SUV(TLR)). The standard of reference was histopathology and/or imaging follow-up. Eighty-nine out of the 134 lesions were positive for metastases. Two-tailed P values were calculated using a chi-square test. A SUV(TLR) greater than 2.0 strongly correlated with metastasis, while less than 2.0 strongly correlated with benign activity. Based on the original interpreter's visual analysis (PET(VA)), (18)F-FDG PET/CT had an accuracy of 74.6% with a high sensitivity (95.5%), but limited specificity (33.3%). Using the SUV(TLR) cutoff value of 2.0 to objectively re-stratify these cases, there was improvement in accuracy to 97.8%, sensitivity to 100%, and specificity to 93.3%. These values were statistically significant by chi-square analysis, with P = 0.0001 for both PET(VA) and SUV(TLR). The 58 MRI lesions and 107 diagnostic CT lesions that were reviewed had accuracies of 70.7% (P = 0.008) and 73.8% (P = 0.0001), respectively. Using a cutoff value of 2.0 for SUV(TLR) to objectively evaluate for potential hepatic metastases on (18)F-FDG PET results in a significant improvement in diagnostic accuracy over subjective visual analysis alone. In this limited study, use of SUV(TLR) more accurately characterized hepatic lesions than the original CT or MRI interpretations.

Comparison of Dynamic and Liver-Specific Gadoxetic Acid Contrast-Enhanced MRI versus Apparent Diffusion Coefficients

BackgroundHepatic lesions often present diagnostic connundrums with conventional MR techniques. Hepatobiliary phase contrast-enhanced imaging with gadoxetic acid can aid in the characterization of such lesions. However, quantitative measures describing late-phase enhancement must be assessed relative to their accuracy of hepatic lesion classification.Purpose: To compare quantitative parameters in gadoxetic acid contrast-enhanced dynamic and hepatobiliary phase imaging versus apparent diffusion coefficients in hepatic lesion characterization.Material and Methods57 patients with focal hepatic lesions on gadoxetic acid MR were included. Lesion enhancement at standard post-contrast time points and in the hepatobiliary phase (HB; 15 and 25 minutes post-contrast) was assessed via calculation of contrast (CR) and enhancement ratios (ER). Apparent diffusion coefficient (ADC) values were also obtained. Values for these parameters were compared among lesions and ROC analyses performed.Results: HB enhancement was greatest with FNH and adenomas. HB ER parameters but not HB CR could distinguish HCC from benign entities (0.9 ER ROC AUC versus 0.5 CR ROC AUC). There was no statistically significant difference found between the 15 and 25 minutes HB time points in detection of any lesion (p>0.4). ADC values were statistically significantly higher with hemangiomas (p<0.05) without greater accuracy in lesion detection relative to HB phase parameters.ConclusionHepatobiliary phase gadoxetic acid contrast-enhanced MR characterizes focal hepatic lesions more accurately than ADC and conventional dynamic post-contrast time point enhancement parameters. ER values are generally superior to CR. No discernible benefit of 25 minute versus 15 minute delayed imaging is demonstrated.

Characterization of hepatic lesions (≤30 mm) with liver-specific contrast agents: A comparison between ultrasound and magnetic resonance imaging

PurposeImaging-based differentiation of hepatic lesions (≤30mm) between well-differentiated hepatocellular carcinomas (w-HCC) and regenerative nodules (RN) presents difficulties. The aim was to compare the diagnostic abilities to differentiate w-HCC from RN using contrast-enhanced ultrasound and magnetic resonance imaging (MRI) both with liver-specific contrast agents. Materials and methodsThis prospective study included 67 pathologically proven hepatic lesions (17.5±5.4mm, 54 w-HCCs, 13 RNs) in 56 patients with chronic hepatitis/cirrhosis (male 40, female 16; 29–79y). Hepatic-arterial/liver-specific phase enhancements were assessed quantitatively by ultrasound with perflubutane microbubble agent and MRI with gadolinium-ethoxybenzyl-diethylenetriamine with respect to the histological findings. ResultsSensitivity, specificity and accuracy of hepatic-arterial phase hyper-enhancement for w-HCC were 59.3%, 100% and 67.2% by ultrasound and 46.3%, 100% and 56.7% by MRI without significant difference. Meanwhile, those of liver-specific-phase hypo-enhancement for w-HCC were 44.4%, 100% and 55.2% by ultrasound and 87.0% (p<0.0001), 46.2% (p=0.0052) and 79.1% (p=0.0032) by MRI. Diagnostic accuracies for w-HCC by area under the receiver operating characteristic curves were higher in the hepatic-arterial phase in ultrasound (0.8316) than MRI (0.6659, p=0.0101) and similar in the liver-specific phase in ultrasound (0.7225) and MRI (0.7347, p=0.8814). ConclusionsHypervascularity is a significant feature which distinguishes w-HCC from RN, and ultrasound exerts a beneficial impact better than MRI for such characterization. However, both imaging have comparable abilities in the characterization of non-hypervascular lesions, compensating mutually for the poor sensitivity of ultrasound and the poor specificity of MRI in the liver-specific phase.

Gd-EOB-DTPA-enhanced magnetic resonance imaging: differentiation between focal nodular hyperplasia and hepatocellular adenoma

Gadoxetic acid (Gd-EOB-DTPA) is a contrast media used in magnetic resonance imaging (MRI) for the detection and characterization of hepatic lesions. It shows combined properties of extracellular and biliary excretion, with 50% of the administered dose eliminated by the hepatobiliary pathway. One of its applications, therefore, is the characterization of focal hepatic lesions, including those of hepatocellular nature, such as focal nodular hyperplasia and hepatocellular adenoma. Patients with focal nodular hyperplasia (FNH) are usually asymptomatic and rarely reveal complications. In other hand, hepatocellular adenoma may suffer complications, such as intraperitoneal or intratumoral (sometimes massive) bleeding and the possible progression to malignancy. To determine the value of MRI with Gd-EOB-DTPA in characterizing hepatic lesions, particularly in the differentiation between HNF and AHC. A retrospective study was carried out by investigating cases of FNH and HCA referred for MR evaluation with Gd-EOB-DTPA in the Department of Radiology of the University Hospitals of Coimbra (HUC) between August 2009 and December 2010. We evaluated 32 patients, 24 with FNH and 8 AHC. The diagnosis was established by histology, follow-up or agreement between imaging methods. In order to evaluate the enhancement after contrast administration in the hepatobiliary phase, we calculated the values of Signal-to-noise ratio (SNR), Contrast-to-noise ratio (CNS) and percentage of enhancement. Statistical analysis was performed with SPSS, version 18, and the tests were evaluated at a significance level of 5%. The SNR and CNR after contrast is significantly different for the two types of lesion (p <0.001 and p = 0.03, respectively), with higher values for both parameters in the group of focal nodular hyperplasia. As for the % of enhancement, there is a statistically significant difference between groups (p = 0.006), again with the FNH group presenting higher values. There are significant differences in both groups among the studies pre-and post-contrast for the CNR (FNH: p <0.001; adenoma: p = 0.017), but for the SNR of the lesion the difference manifests in the HNF group (p <0,001); the CNR values increase in FNH and decrease in hepatocellular adenoma, while for the SNR of the lesion post-contrast values are higher than pre-contrast, in both groups. Magnetic resonance imaging with hepatospecific contrast is a valuable method for characterization of benign hepatic lesions, helping to differentiate FNH from HCA, based on the different patterns of uptake and retention of Gd-EOB-DTPA.

Parametric images via dynamic 18F-fluorodeoxyglucose positron emission tomographic data acquisition in predicting midterm outcome of liver metastases secondary to gastrointestinal stromal tumours

(18)F-Fluorodeoxyglucose positron emission tomography (FDG PET) may underestimate viable tumour tissue in patients with gastrointestinal stromal tumours (GIST) treated with molecular targeted agents. The aim of the present study was to investigate the value of parametric images generated after dynamic data acquisition for the detection of active liver metastases. The analysis included 65 dynamic FDG PET studies in 34 patients with liver metastases from GIST who were treated with imatinib or sunitinib. Parametric images of intercept and slope were calculated by dedicated software using a voxel-based linear regression of time-activity data. Intercept images represent the tracer's distribution volume and the slope its overall metabolic turnover. All images were assessed visually and semi-quantitatively. Liver disease status was established 12 months after each PET study. Dichotomous variables of visual interpretation and various quantitative parameters were entered in a statistical model of linear discriminant analysis. Visual analysis of slope images was more sensitive than the standard 1-h FDG uptake evaluation (70.6 vs 51.0%, p = 0.016) in detecting cases with liver disease progression (n = 51). Specificity did not differ. Combination of all variables in the discriminant analysis model correctly classified 87.7% of cases as progressive or non-progressive disease. Sensitivity was raised to 88.2%. Parametric images of intercept and slope add a new dimension to the interpretation of FDG PET studies, by isolating visually and quantifying the perfusion and phosphorylation-dependent part of tracer uptake. In treated GIST patients, integration of this information with the 1-h uptake data achieves better characterization of hepatic lesions with respect to disease activity.

Contrast-enhanced ultrasound for characterisation of hepatic lesions appearing non-hypervascular on CT in chronic liver diseases

The purpose of this prospective study was to elucidate the efficacy of using contrast-enhanced ultrasound to characterise focal hepatic lesions appearing non-hypervascular on contrast-enhanced CT in chronic liver diseases. The study population included 22 patients with cirrhosis or chronic hepatitis, who between them had 27 focal hepatic lesions smaller than 20 mm (mean 13.9 ± 3.4) that appeared non-hypervascular on contrast-enhanced CT. Contrast-enhanced ultrasound with perflubutane microbubble agent (Sonazoid, 0.0075 ml kg(-1)) was performed prior to ultrasound-guided needle biopsy, and intensity analysis was done for hepatic lesions in the early phase (-60 s) and late phase (600 s post injection). All seven early-phase hyperenhanced lesions were hepatocellular carcinoma (HCC). 20 lesions iso- or hypoenhanced during the early phase consisted of 11 regenerative nodules (RNs) and 9 HCCs. HCC was more frequent in early-phase hyperenhanced lesions than in iso- or hypoenhanced lesions (p=0.0108). Both late-phase hypoenhanced lesions were HCCs, whereas 25 late-phase isoenhanced lesions consisted of 11 RNs and 14 HCCs. The enhancement patterns of the 11 RNs included isoenhanced appearance in both the early and late phases in 8 lesions, and early-phase hypoenhancement combined with late-phase isoenhancement in the remaining 3. Both of these enhancement patterns (i.e. either iso-iso or hypo-iso) were found in 9 malignant lesions, 9 (75%) of the 12 well-differentiated HCCs. Hypervascularity on contrast-enhanced ultrasound with Sonazoid strongly suggested HCC regardless of non-hypervascularity on CT, and late-phase hypoenhancement was another possible finding of HCC. However, characterisation of hepatic lesions with other enhancement patterns was difficult using our technique.

Positron emission tomography scan for a hepatic mass

A 66-year-old male patient who is hepatitis C RNA positive, without cirrhosis, has been found to have a mass on ultrasound examination of the liver. Physical examination is unremarkable. The hemoglobin, white cell count and platelet counts are normal. The alkaline phosphatase is mildly elevated to 212 U/L(normal <115), the AST 112 U/L, and the ALT 128 U/L. The CA 19-9 is 82 U/mL (normal < 55 U/mL) and the alpha fetoprotein 12 ng /mL. A CT scan of the abdomen shows a vague mass in segment V of the liver without definite arterial enhancement. An MRI of the abdomen is carried out with contrast but the mass is still indeterminate on T1 and T2 imaging.

The detection and discrimination of malignant and benign focal hepatic lesions:T2weightedvsdiffusion-weighted MRI

The purpose of this study was to evaluate the use of diffusion-weighted imaging (DWI) for the detection and characterisation of focal hepatic lesions compared with the use of T(2) weighted imaging. 45 patients with 97 hepatic lesions (51 malignant lesions and 46 benign lesions) were included in this retrospective study. Malignant hepatic lesions included 12 hepatocellular carcinomas, 26 metastases and 13 intrahepatic cholangiocarcinomas. Benign hepatic lesions included 19 haemangiomas and 27 cysts. The MRI protocol for the upper abdomen included T(2) weighted images, in- and opposed-phase T(1) weighted images and dynamic T(1) weighted images. Breath-hold fat-suppressed single-shot echo planar DWI was performed with the following parameters: 1338/66; b factors, 0, 50 and 800 s mm(-2). Two independent observers reviewed the T(2) weighted images and the DWI to detect and to characterise the hepatic lesions. For detection of malignant hepatic lesions, the use of DWI showed a significantly higher detection rate than the use of T(2) weighted images (p<0.05). However, there was no significant difference between the use of DWI and T(2) weighted images for benign hepatic lesions. For the differentiation between malignant and benign hepatic lesions, there was no significant difference in sensitivity, specificity and accuracy between the use of T(2) weighted images and the use of DWI. The use of DWI was better for the detection of malignant hepatic lesions than the use of T(2) weighted images. However, for detection of benign hepatic lesions and characterisation of hepatic lesions, the use of DWI was equivalent to the use of T(2) weighted images.

Contrast-enhanced intraoperative ultrasound improves detection of liver metastases during surgery for primary colorectal cancer

BackgroundComputed tomography (CT) is the most common staging investigation in colorectal cancer (CRC). Up to 25% of patients are found to have previously undetected hepatic lesions when intraoperative ultrasound (IOUS) of the liver is used during CRC resection. We aimed to assess the ability of IOUS to detect additional liver lesions/metastases at primary colorectal resection, and to evaluate whether contrast-enhanced IOUS (CE-IOUS) improves the detection and characterization of hepatic lesions. MethodsWe performed a single-centre, prospective pilot study. At CRC resection, patients underwent IOUS of the liver. Contrast-enhanced IOUS of the liver was undertaken using i.v. sulphur hexafluoride micro-bubbles (SonoVue®, 4.8ml). Findings of CT, non-enhanced IOUS and CE-IOUS were compared. Changes in staging or management were noted. Additional lesions were corroborated with iron oxide magnetic resonance imaging (MRI). ResultsAmong 21 patients, IOUS demonstrated additional lesions in seven (33%). Contrast altered the diagnosis of non-enhanced IOUS in four (20%) and changed the management strategy in three (14%) patients. Thus, IOUS in combination with the contrast agent altered the intraoperative or postoperative management plan in four patients. ConclusionsIn the first study of its kind, early results suggest that the ability of IOUS to detect additional metastases is improved by CE-IOUS, and that this may impact on surgical staging and management.

The value of contrast enhanced ultrasound (CEUS) in the characterisation of patients with renal masses

Renal masses are frequently incidentally found on ultrasound. Contrast enhanced computed tomography (CECT) is regarded as the method of choice. Contrast enhanced ultrasound (CEUS) has a high impact for characterisation of hepatic lesions. Its use in renal masses has been less comprehensively studied. Two hundred and one patients referred for surgical treatment of a renal mass, 143 patients fulfilling inclusion criteria (histology and reference method). Baseline ultrasound and CEUS with BR1, histology obtained by surgery (89%) or biopsy (11%). Eighty-eight percent of the patients had renal lesions which were malignant and 12% benign lesions. Eighty percent had renal cell carcinoma (RCC). Seven percent of the lesions were cystic. Two patients were upgraded by CEUS from CECT Bosniak II into CEUS Bosniak III resp. IV. CEUS could predict malignancy with a sensitivity, specificity, positive, negative predictive value and accuracy in 97%, 45%, 91%, 75%, and 90%. The correct staging was diagnosed by CEUS (CECT) in 83% (69%). CEUS was superior to CECT in the staging and characterisation of RCC, also in the subgroup of patients with cystic lesions. CEUS can replace CECT e.g. in patients with allergies or contraindications against CECT. Multicentre studies are necessary to confirm the findings.