Published online Feb 14, 2018. doi: 10.3748/wjg.v24.i6.744
Peer-review started: December 8, 2017
First decision: December 21, 2017
Revised: January 3, 2018
Accepted: January 16, 2018
Article in press: January 16, 2018
Published online: February 14, 2018
With the advent of ultrasound contrast agents, contrast-enhanced ultrasound (CEUS) is playing a more and more important role clinically. CEUS is a safe, convenient and repeatable imaging method, with no risk of serious allergy and radiation. CEUS has an excellent diagnostic efficiency for hepatic focal lesions, which is comparable with contrast-enhanced computed tomography. However, the value of CEUS in gallbladder lesions was not widely accepted yet.
The European Federation of Societies for Ultrasound in Medicine and Biology guidelines 2011 did not recognize the value of CEUS for the differential diagnosis of gallbladder lesions. However, there were still some studies published which showed the usefulness of CEUS in the differential diagnosis between benign and malignant gallbladder diseases. So, the value of CEUS for gallbladder is still unclear.
We aim to describe CEUS features and evaluate differential diagnosis value of CEUS and conventional ultrasound for patients with benign and malignant gallbladder lesions.
This study included 105 gallbladder lesions, which were examined using conventional ultrasound and CEUS before surgical resection and pathological examination in our hospital between December 2012 and October 2016. Each lesion was diagnosed as (1) benign, (2) probably benign, (3) probably malignant or (4) malignant using both conventional ultrasound and CEUS by two radiologists with at least ten years’ experience in both conventional ultrasound and CEUS. CEUS features of these gallbladder lesions were analyzed. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of conventional ultrasound and CEUS was calculated and compared.
Gallbladder sludge was completely nonenhanced on CEUS. Gallbladder adenomyomatosis had typical characteristics of small nonenhanced areas on CEUS, together with echogenic foci and tail sign sometimes. Gallbladder cancer on CEUS was usually heterogeneously hyperenhanced on arterial phase and washed out quickly. Besides providing microvascular information, CEUS makes the contour of a lesion much clearer and the evaluation of a lesion’s shape, size and boundary much more accurate.
The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CEUS were 94.1%, 95.5%, 80.0%, 98.8% and 95.2%, respectively; these values were significantly higher than conventional ultrasound (82.4%, 89.8%, 60.9%, 96.3% and 88.6%, respectively).
CEUS helped in the differential diagnosis between among different kinds of gallbladder lesions. The diagnostic efficiency of CEUS was highly improved compared with conventional ultrasound. According to our results, for a gallbladder lesion, when a definite diagnosis could not be made using conventional ultrasound, CEUS examination could be used as a further diagnostic method.
In this study, we demonstrated the value of CEUS for gallbladder lesions. Prospective study with large numbers of patients and different kinds of gallbladder lesions will be needed to confirm the results. The application of endoscopic CEUS may provide more useful information for differentiating between benign and malignant gallbladder lesions.