Quantitative perfusion analysis of transabdominal contrast-enhanced ultrasonography of pancreatic masses and carcinomas.
OBJECTIVE
Preoperative differential diagnosis of pancreatic ductal adenocarcinoma (PDAC) and focal masses in patients with chronic pancreatitis (CP) can be challenging. There are fine differences in the vascularization of these lesions; ultrasound contrast agents can aid in their differentiation. We evaluated the value of software-aided quantitative analysis of transabdominal contrast-enhanced ultrasonography for differential diagnosis of PDAC vs focal masses.


METHODS
Sixty patients for whom it was not possible to differentiate between an inflammatory focal lesion of the pancreas and a pancreatic carcinoma underwent contrast-enhanced ultrasonography with a second-generation contrast agent. Time-intensity curves were obtained for all exams in 2 regions of interest within the lesion and within the normal pancreatic tissue. Images were processed using Axius ACQ software; the following parameters were obtained: maximum intensity, arrival time, time-to-peak, and area under the curve. Absolute values and differences between the lesion and the normal tissue were evaluated.


RESULTS
Histology analysis revealed 45 PDACs and 15 inflammatory masses in patients with CP. Time-dependent parameters (arrival time and time to peak) were significantly longer in PDACs compared to focal masses. Although markedly lower than in healthy pancreata, the maximum intensity and area under the curve parameters were not significantly different between PDACs and focal lesions in patients with CP.


CONCLUSIONS
In cases of CP, PDAC and focal masses exhibit different perfusion patterns at a capillary level that can be visualized using the small microbubbles of ultrasound contrast agents. Contrast quantification software supplements a subjective visual assessment with objective criteria to facilitate the differential diagnosis of focal lesions in pancreatic cancer and chronic pancreatitis.
Kersting
Stephan
S
Department of General, Thoracic and Vascular Surgery, School of Medicine, Dresden University of Technology, Dresden, Germany. stephan.kersting@uniklinikum-dresden.de
Konopke
Ralf
R
Kersting
Florina
F
Volk
Andreas
A
Distler
Marius
M
Bergert
Hendrik
H
Saeger
Hans-Detlev
HD
Grützmann
Robert
R
Bunk
Alfred
A
D001783:Blood Flow Velocity; D002196:Capillaries / Q000000981:diagnostic imaging; D021441:Carcinoma, Pancreatic Ductal / Q000098:blood supply / Q000000981:diagnostic imaging*; D016022:Case-Control Studies; D003287:Contrast Media; D006104:Granuloma, Plasma Cell / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D045423:Microbubbles; D010179:Pancreas / Q000098:blood supply / Q000000981:diagnostic imaging*; D010190:Pancreatic Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging*; D050500:Pancreatitis, Chronic / Q000000981:diagnostic imaging*; D055420:Perfusion Imaging / Q000379:methods*; D010743:Phospholipids; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012039:Regional Blood Flow; D013459:Sulfur Hexafluoride; D014463:Ultrasonography
D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride