AIM:To investigate the diagnostic performance of acoustic radiation force impulse(ARFI) elastography for characterizing focal liver mass by quantifying their stiffness.METHODS:This prospective study included 62 patien...AIM:To investigate the diagnostic performance of acoustic radiation force impulse(ARFI) elastography for characterizing focal liver mass by quantifying their stiffness.METHODS:This prospective study included 62 patients with a focal liver mass that was well visualized on conventional ultrasonography performed in our institution from February 2011 to November 2011.Among them,12 patients were excluded for ARFI measurement failure due to a lesion that was smaller than the region of the interest and at an inaccessible location(deeper than 8 cm)(n = 7) or poor compliance to hold their breath as required(n = 5).Finally,50 patients with valid ARFI measurements were enrolled.If a patient had multiple liver masses,only one mass of interest was chosen.The masses were diagnosed by histological examination or clinical diagnostic criteria.During ultrasonographic evaluation,stiffness,expressed as velocity,was checked 10 times per focal liver mass and the surrounding liver parenchyma.RESULTS:After further excluding three masses that were non-diagnostic on biopsy,a total of 47 focal mass lesions were tested,including 39(83.0%) malignant masses [24 hepatocellular carcinomas(HCC),seven cholangiocellular carcinomas(CCC),and eight liver metastases] and eight(17.0%) benign masses(five hemangiomas and three focal nodular hyperplasias,FNH).Thirty-seven(74.0%) masses were confirmed by histological examination.The mean velocity was 2.48 m/s in HCCs,1.65 m/s in CCCs,2.35 m/s in metastases,1.83 m/s in hemangiomas,and 0.97 m/s in FNHs.Although considerable overlap was still noted between malignant and benign masses,significant differences in ARFI values were observed between malignant and benign masses(mean 2.31 m/s vs 1.51 m/s,P = 0.047),as well as between HCCs and benign masses(mean 2.48 m/s vs 1.51 m/s,P = 0.006).The areas under the receiver operating characteristics curves(AUROC) for discriminating the malignant masses from benign masses was 0.724(95%CI,0.566-0.883,P = 0.048),and the AUROC for discriminating HCCs from benign masses was 0.813(95%CI,0.649-0.976,P = 0.008).To maximize the sum of sensitivity and specificity,an ARFI value of 1.82 m/s was selected as the cutoff value to differentiate malignant from benign liver masses.Furthermore,the cutoff value for distinguishing HCCs from benign masses was also determined to be 1.82 m/s.The diagnostic performance of the sum of the ARFI values for focal liver masses and the surrounding liver parenchyma to differentiate liver masses improved(AUROC = 0.853;95%CI,0.745-0.960;P = 0.002 in malignant liver masses vs benign ones and AUROC = 0.948;95%CI,0.896-0.992,P < 0.001 in HCCs vs benign masses).CONCLUSION:ARFI elastography provides additional information for the differential diagnosis of liver masses.However,our results should be interpreted in clinical context,because considerable overlap in ARFI values existed among liver masses.展开更多
The extensive use of imaging techniques in differential diagnosis of abdominal conditions and screening of hepatocellular carcinoma in patients with chronic hepatic diseases,has led to an important increase in identif...The extensive use of imaging techniques in differential diagnosis of abdominal conditions and screening of hepatocellular carcinoma in patients with chronic hepatic diseases,has led to an important increase in identification of focal liver lesions.The development of contrastenhanced ultrasound(CEUS) opens a new window in the diagnosis and follow-up of these lesions.This technique offers obvious advantages over the computed tomography and magnetic resonance,without a decrease in its sensitivity and specificity.The new second generation contrast agents,due to their intravascular distribution,allow a continuous evaluation of the enhancement pattern,which is crucial in characterization of liver lesions.The dual blood supply in the liver shows three different phases,namely arterial,portal and late phases.The enhancement during portal and late phases can give important information about the lesion's behavior.Each liver lesion has a different enhancement pattern that makes possible an accurate approach to their diagnosis.The role of emerging techniques as a contrastenhanced three-dimensional US is also discussed.In this article,the advantages,indications and technique employed during CEUS and the different enhancement patterns of most benign and malignant focal liver lesions are discussed.展开更多
基金Supported by A Grant of the Korea Healthcare Technology R and D Project,Ministry of Health and Welfare,South Korea, A102065
文摘AIM:To investigate the diagnostic performance of acoustic radiation force impulse(ARFI) elastography for characterizing focal liver mass by quantifying their stiffness.METHODS:This prospective study included 62 patients with a focal liver mass that was well visualized on conventional ultrasonography performed in our institution from February 2011 to November 2011.Among them,12 patients were excluded for ARFI measurement failure due to a lesion that was smaller than the region of the interest and at an inaccessible location(deeper than 8 cm)(n = 7) or poor compliance to hold their breath as required(n = 5).Finally,50 patients with valid ARFI measurements were enrolled.If a patient had multiple liver masses,only one mass of interest was chosen.The masses were diagnosed by histological examination or clinical diagnostic criteria.During ultrasonographic evaluation,stiffness,expressed as velocity,was checked 10 times per focal liver mass and the surrounding liver parenchyma.RESULTS:After further excluding three masses that were non-diagnostic on biopsy,a total of 47 focal mass lesions were tested,including 39(83.0%) malignant masses [24 hepatocellular carcinomas(HCC),seven cholangiocellular carcinomas(CCC),and eight liver metastases] and eight(17.0%) benign masses(five hemangiomas and three focal nodular hyperplasias,FNH).Thirty-seven(74.0%) masses were confirmed by histological examination.The mean velocity was 2.48 m/s in HCCs,1.65 m/s in CCCs,2.35 m/s in metastases,1.83 m/s in hemangiomas,and 0.97 m/s in FNHs.Although considerable overlap was still noted between malignant and benign masses,significant differences in ARFI values were observed between malignant and benign masses(mean 2.31 m/s vs 1.51 m/s,P = 0.047),as well as between HCCs and benign masses(mean 2.48 m/s vs 1.51 m/s,P = 0.006).The areas under the receiver operating characteristics curves(AUROC) for discriminating the malignant masses from benign masses was 0.724(95%CI,0.566-0.883,P = 0.048),and the AUROC for discriminating HCCs from benign masses was 0.813(95%CI,0.649-0.976,P = 0.008).To maximize the sum of sensitivity and specificity,an ARFI value of 1.82 m/s was selected as the cutoff value to differentiate malignant from benign liver masses.Furthermore,the cutoff value for distinguishing HCCs from benign masses was also determined to be 1.82 m/s.The diagnostic performance of the sum of the ARFI values for focal liver masses and the surrounding liver parenchyma to differentiate liver masses improved(AUROC = 0.853;95%CI,0.745-0.960;P = 0.002 in malignant liver masses vs benign ones and AUROC = 0.948;95%CI,0.896-0.992,P < 0.001 in HCCs vs benign masses).CONCLUSION:ARFI elastography provides additional information for the differential diagnosis of liver masses.However,our results should be interpreted in clinical context,because considerable overlap in ARFI values existed among liver masses.
文摘The extensive use of imaging techniques in differential diagnosis of abdominal conditions and screening of hepatocellular carcinoma in patients with chronic hepatic diseases,has led to an important increase in identification of focal liver lesions.The development of contrastenhanced ultrasound(CEUS) opens a new window in the diagnosis and follow-up of these lesions.This technique offers obvious advantages over the computed tomography and magnetic resonance,without a decrease in its sensitivity and specificity.The new second generation contrast agents,due to their intravascular distribution,allow a continuous evaluation of the enhancement pattern,which is crucial in characterization of liver lesions.The dual blood supply in the liver shows three different phases,namely arterial,portal and late phases.The enhancement during portal and late phases can give important information about the lesion's behavior.Each liver lesion has a different enhancement pattern that makes possible an accurate approach to their diagnosis.The role of emerging techniques as a contrastenhanced three-dimensional US is also discussed.In this article,the advantages,indications and technique employed during CEUS and the different enhancement patterns of most benign and malignant focal liver lesions are discussed.
