Added value of intravenous contrast-enhanced ultrasound for characterization of cystic pancreatic masses: a prospective study on 37 patients.
The aim of this study was to evaluate the added value of contrast-enhanced ultrasound (CEUS) in the pancreatic cystic mass (PCM) diagnosis by using a qualitative and quantitative analysis in order to make a relevant characterization.


METHODS
Between December 2008 and November 2011, 37 patients with PCM discovered at ultrasound examination were prospectively followed. A qualitative and quantitative CEUS analysis was performed in order to differentiate etiologies of the PCM. In the quantitative analysis several parameters were followed: Peak Intensity (PI), Time to Peak (TTP), maximum ascending gradient (GRAD), Time to maximum gradient (TTG) and Area Under the Curve (AUC). Normalized ratios were also calculated. In all patients a definite cytological or histological diagnosis was obtained.


RESULTS
Thirty-seven patients were studied: 12 with pancreatitis-associated pseudocyst and 25 with cystic tumors (10 serous cystic adenoma, 5 mucinous cystic adenoma, 6 cystadenocarcinomas, 2 solid pseudopapillary tumors and 2 intraductal papillary mucinous neoplasms). There was a significant difference of the nAUC and nTTP between pseudocyst and cystic tumors, p=0.03 and p=0.01, respectively. A normalized TTP value above 7 sec was suggestive for the diagnosis of pseudocysts with 79.16 % accuracy. There was a significant difference of nTTP and nTTG between the benign and malignant lesions. nTTP < 9 sec and nTTG < 8.5 sec rules out malignant cysts in almost 90% of cases.


CONCLUSIONS
The CEUS is useful in the diagnosis of PCM. The quantitative analysis of the enhancement of the cystic wall may discriminate the different types of the PCM.
Radiology Department, Regional Institute of Hepatology and Gastroenterology Octavian Fodor, University of Medicine and Pharmacy Iuliu Haţieganu, Cluj-Napoca, Romania.
Tudor Andrei
TA
Vasile
Mihai
M
Socaciu
Roxana
R
Stan Iuga
Andrada
A
Seicean
Cornel
C
Iancu
Nadim
N
al Hajjar
Toader
T
Zaharie
Radu
R
Badea
D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D010181:Pancreatic Cyst / Q000150:complications* / Q000000981:diagnostic imaging*; D010190:Pancreatic Neoplasms / Q000150:complications* / Q000000981:diagnostic imaging*; D010743:Phospholipids; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013459:Sulfur Hexafluoride; D014463:Ultrasonography / Q000379:methods*
D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride