The ultrasonographic appearance and location of the canine pancreas have been described, but neither the size of the pancreas nor the presence of the pancreatic duct has been adequately assessed.1–4 Acute pancreatitis in dogs is a common disease that can often be diagnosed ultrasonographically because the pancreas is enlarged, hypoechoic, and frequently surrounded by hyperechoic peripancreatic fat.2 However, in chronic pancreatitis, morphological and consequently ultrasonographic changes may be subtle or complex, compared with those in acute pancreatitis.5,6 The incidence of chronic pancreatitis in dogs is still unknown and may be underestimated, as determined in a recent postmortem study7 in which chronic pancreatitis was diagnosed in 51 of 151 (34%) dogs. Additionally, pancreatic insufficiency is reportedly associated with a reduction in size of the pancreas.8
Established reference values of ultrasonographic pancreatic size have been reported for clinically normal cats,9–11 but no published data are available for dogs of various ages and sizes. Although the ultrasonographic appearance of the pancreatic duct has been described in cats, it has not been adequately described in dogs. A relationship between pancreatic duct dilation and pancreatitis in dogs12 or cats13 has been proposed; however, dilation of the pancreatic duct has also been reported as an incidental, age-related change in cats.10,11 To aid in evaluation of the endoscopic ultrasonographic appearance of chronic pancreatitis in humans, dogs with chronic pancreatitis were evaluated, which revealed sequential changes such as accentuated lobularity, changes in parenchymal echogenicity, and irregular margins of the pancreatic duct and branches.14
The resolution and quality of ultrasonographic equipment is increasing, and the clinicopathologic knowledge about pancreatic disorders in dogs is improving; therefore, it is becoming increasingly important to have reference values for pancreas and pancreatic duct size. The main objective of the study reported here was to describe the appearance and size of the pancreas and pancreatic duct in a large population of dogs with no clinical evidence of gastrointestinal tract disease. The second objective was to assess the potential effects of age and body weight on the measurements.
iU22 xMATRIX ultrasound system, Philips Healthcare, Andover, Mass.
LOGIQ 7, GE Healthcare, Little Chalfont, Buckinghamshire, England.
XVision MyLab 70, Esaote, Genova, Italy.
SAS, version 9.2, TS kevel 2M0 for Windows XP_PRO platform, SAS Institute Inc, Cary, NC.
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