Ultrasonographic and colour Doppler features of intrapancreatic splenic tissue in a cat

CASE SUMMARY: A 2-year-old female neutered domestic longhair cat was referred for a 3-day history of lethargy and anorexia. Physical examination documented abdominal distension and pain, which, alongside marked electrolyte imbalances on blood biochemistry, was highly suspicious for a gastrointestinal obstruction. This was confirmed on diagnostic imaging, with abdominal ultrasonography also identifying an incidental, well-defined small lobular hypoechoic nodule adjacent to the tail of the spleen, with high vascularity on Doppler interrogation. This was identified as a focal nodule at the tip of the left limb of the pancreas at surgery, and resected via partial pancreatectomy. Histopathological examination confirmed intrapancreatic splenic tissue. RELEVANCE AND NOVEL INFORMATION: This case report presents the first available ultrasonographic description and images of intrapancreatic splenic tissue in a cat. It is thought to be a benign lesion of low clinical significance and therefore defining its imaging characteristics may allow for improvement in diagnostic suspicion without resorting to excisional surgery.