Pancreatitis in dogs (Proceedings)

Ultrasonography is part of the routine diagnostic method to evaluate pancreatic disorders in small animals.

Pancreatitis has various ultrasonographic appearances due to the varying degrees of pancreatic and peripancreatic tissue inflammation, and the stage of the disease process.  

In dogs, acute pancreatitis is a common disorder that often can be diagnosed and monitored using ultrasound.

Pancreatitis

The hallmark US features of pancreatitis often include: enlarged pancreas and locally or diffusely hypoechoic parenchyma, moderately hyperechoic (or mixed echogenicity) surrounding fat due to saponification, and peritoneal effusion. 

In severe hemorrhagic, necrotizing pancreatitis an irregular hypoechoic area is seen in the pancreatic region.  The adjacent mesentery is hyperechoic because of inflammation and edema.   Complications of pancreatitis include….Previously described pancreatic phelgmons associated with acute pancreatitis actually represent the combined areas of pancreatic necrosis/hemorrhage surrounded by inflamed mesentery/omentum.

Pancreatic abscess(es) appear as hypoechoic focal lesions containing pus and necrotic tissue.  Pseudocysts associated with pancreatitis are rare in dogs, they are fluid-filled masses surrounded by a capsule of granulation and fibrous tissue.  The fluid is pancreatic secretions which escape from a ruptured duct.  They can appear as anechoic/hypoechoic masses with inconsistent acoustic enhancement and varying amounts of internal echoes.  Ultrasonographic differentiation between a pancreatic abscess and pseudocyst is not possible.

Less severe ultrasonographic changes of the pancreas and peripancreatic tissue commonly are seen in dogs with transient, subtle clinical signs associated with pancreatitis.  Ultrasonographically, the pancreas remains a distinct, well-defined hypoechoic structure contrasting with the slightly hyperechoic peripancreatic mesentery.

Differential Diagnosis

References

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