title: Contrast-enhanced ultrasound in diagnosis of gallbladder adenoma.
abstract: BACKGROUND
  Gallbladder adenoma is a pre-cancerous neoplasm and needs surgical resection. It is difficult to differentiate adenoma from other gallbladder polyps using imaging examinations. The study aimed to illustrate characteristics of contrast-enhanced ultrasound (CEUS) and its diagnostic value in gallbladder adenoma.
  
  
  METHODS
  Thirty-seven patients with 39 gallbladder adenomatoid lesions (maximal diameter ≥10 mm and without metastasis) were enrolled in this study. Lesion appearances in conventional ultrasound and CEUS were documented. The imaging features were compared individually among gallbladder cholesterol polyp, gallbladder adenoma and malignant lesion.
  
  
  RESULTS
  Adenoma lesions showed iso-echogenicity in ultrasound, and an eccentric enhancement pattern, "fast-in and synchronous-out" contrast enhancement pattern and homogeneous at peak-time enhancement in CEUS. The homogenicity at peak-time enhancement showed the highest diagnostic ability in differentiating gallbladder adenoma from cholesterol polyps. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy and Youden index were 100%, 90.9%, 92.9%, 100%, 95.8% and 0.91, respectively. The characteristic of continuous gallbladder wall shown by CEUS had the highest diagnostic ability in differentiating adenoma from malignant lesion (100%, 86.7%, 86.7%, 100%, 92.9% and 0.87, respectively). The characteristic of the eccentric enhancement pattern had the highest diagnostic ability in differentiating adenoma from cholesterol polyp and malignant lesion, with corresponding indices of 69.2%, 88.5%, 75.0%, 85.2%, 82.1% and 0.58, respectively.
  
  
  CONCLUSIONS
  CEUS is valuable in differentiating gallbladder adenoma from other gallbladder polyps (≥10 mm in diameter). Homogeneous echogenicity on peak-time enhancement, a continuous gallbladder wall, and the eccentric enhancement pattern are important indicators of gallbladder adenoma on CEUS.
authors: Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai 200032, China. puguang61@126.com.
authors: Hai-Xia
authors: HX
authors: Yuan
authors: Jia-Ying
authors: JY
authors: Cao
authors: Wen-Tao
authors: WT
authors: Kong
authors: Han-Sheng
authors: HS
authors: Xia
authors: Xi
authors: X
authors: Wang
authors: Wen-Ping
authors: WP
authors: Wang
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging*; D000236:Adenoma / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002784:Cholesterol / Q000378:metabolism; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D005704:Gallbladder / Q000000981:diagnostic imaging / Q000473:pathology*; D005706:Gallbladder Neoplasms / Q000000981:diagnostic imaging*; D006801:Humans; D006965:Hyperplasia / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011127:Polyps / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D014463:Ultrasonography; D055815:Young Adult
chemical_list: D003287:Contrast Media; D002784:Cholesterol