Ultrasound Imaging of Experimental Venous Thrombus in Dogs Using Doppler and CEUS Techniques

Venous thrombosis has been extensively researched in humans, but studies focusing on dogs remain limited. This investigation aimed to evaluate the formation and resolution of venous thrombi in dogs using various ultrasonographic techniques. The study involved nine healthy Beagle dogs, in which venous thrombi were created by puncturing the lumen of the external jugular veins. Following thrombus formation, the veins were examined using B-mode ultrasound, color Doppler, pulsed-wave Doppler, and contrast-enhanced ultrasound (CEUS) at regular intervals over 210 to 270 minutes post-venipuncture. Haemodynamic parameters were measured at two locations, both before and after thrombus formation, to assess changes in blood flow. The presence of a thrombus was confirmed through CEUS imaging, which provided detailed visualization of the thrombus’s size and shape. The study found that the use of color Doppler was sometimes ineffective in visualizing venous thrombi in certain veins. Notably, blood volume emerged as the most reliable parameter for indicating thrombus presence, with volumes below 0.001 cm³ proving undetectable via traditional haemodynamic assessments. In contrast, CEUS accurately depicted an anechoic venous thrombus, demonstrating its potential utility for early thrombus detection even at minimal volumes. This study highlights the importance of advanced ultrasound techniques in the assessment of venous thrombosis in dogs and underscores the need for further research to develop diagnostic protocols specific to veterinary medicine.