Added Value of Contrast-Enhanced Ultrasound for Cytological Sample Collection of Hepatic and Pulmonary Masses in Dogs

Ultrasound (US)-guided cytological sample collection (CSC) is widely used for the evaluation of hepatic and pulmonary masses in dogs; however, the presence of intralesional necrosis may reduce diagnostic yield. Contrast-enhanced ultrasonography (CEUS) allows improved assessment of lesion microvascularization and may help identify viable tissue prior to sampling. The aim of this study is to compare the diagnostic yield of CEUS-aided CSC with conventional B-mode US-guided CSC in dogs with hepatic and pulmonary masses. This prospective controlled study with matched controls included 54 client-owned dogs. Twenty-seven dogs underwent CEUS-aided CSC, while 27 matched control dogs underwent conventional B-mode US-guided CSC. Cytological samples were evaluated for diagnostic adequacy, and logistic regression analysis was used to compare groups. No significant difference was found in the probability of obtaining diagnostically adequate samples between techniques. However, CEUS identified non-enhancing areas consistent with presumed necrosis more frequently and with greater extent compared with B-mode US (p < 0.05). Although CEUS did not significantly increase overall diagnostic adequacy, it improved identification and delineation of necrotic areas, providing procedurally relevant information for more targeted sampling.