Quantitative Ultrasound and the Pancreas: Demonstration of Early Detection Capability

Rita J Miller; Aiguo Han; John W Erdman Jr; Matthew A Wallig; William D O'Brien Jr

doi:10.1002/jum.14901

Quantitative Ultrasound and the Pancreas: Demonstration of Early Detection Capability

J Ultrasound Med. 2019 Aug;38(8):2093-2102. doi: 10.1002/jum.14901. Epub 2018 Dec 21.

Authors

Rita J Miller¹, Aiguo Han¹, John W Erdman Jr², Matthew A Wallig³, William D O'Brien Jr¹

Affiliations

¹ Bioacoustics Research Laboratory, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
² Department of Food Science and Human Nutrition , University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
³ Department of Pathobiology , University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.

Abstract

Objectives: To show that quantitative ultrasound biomarkers attenuation (AC) and backscatter (BSC) coefficients are effective tools to detect early changes in acute pancreatitis, using a cerulein-induced pancreatitis rat model.

Methods: Sprague-Dawley rats (n = 68) were divided into 8 groups: uninjected cage controls, saline-injected controls, and cerulein-injected rats euthanized at 2, 4, 15, 24, 48, and 60 hours after injection. Pancreatic AC and BSC (25-55 MHz) were estimated in vivo (Vevo 2100, VisualSonics, Toronto, CA) and ex vivo (40-MHz transducer). The pancreas of each rat was evaluated histopathologically.

Results: Changes in both in vivo and ex vivo AC and BSC relative to controls reflected temporal histomorphologic changes. Overall, there were decreased AC and BSC at early time points and then rebound toward control values over time. Maximal in vivo AC and BSC decreases occurred at 2 hours after cerulein injection. Attenuation coefficient changes corresponded well with early pancreatic edema and acinar cell vacuolation, with rebound as edema decreased, autophagy/cellular death occurred, and histiocytic infiltrates and fibrosis manifested. Backscatter coefficient decreased early but rebounded as autophagy and apoptosis increased, only to fall as acinar atrophy peaked, and fibrosis and histiocytic infiltration increased.

Conclusions: Cerulein-induced pancreatitis is an excellent model for studying ultrasonic AC and BSC biomarkers during the early stages of acute pancreatitits, reflecting microscopic structural changes. Edema followed by cell shrinkage and apoptosis, then histiocytic infiltration and fibrosis, has certain similarities with the morphologies of some forms of pancreatic carcinoma. This suggests that quantitative ultrasound may be very useful for early detection of disease onset or response to therapy for not only acute pancreatitis but also pancreatic cancer.

Keywords: attenuation coefficient (AC); backscatter coefficient (BSC); cerulein; early detection; pancreatitis; quantitative ultrasound.

Publication types

Evaluation Study

MeSH terms

Acute Disease
Animals
Disease Models, Animal
Early Diagnosis
Evaluation Studies as Topic
Female
Pancreas / diagnostic imaging
Pancreatitis / diagnostic imaging*
Rats
Rats, Sprague-Dawley
Ultrasonography / methods*

Abstract

Publication types

MeSH terms

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