Time-dependent hardening of blood clots quantitatively measured in vivo with shear-wave ultrasound imaging in a rabbit model of venous thrombosis.
OBJECTIVE
Provide in vivo blood clot hardening evolution with ultrasound using supersonic imaging of shear waves.


METHODS
We conducted a prospective study in flow stasis-induced venous thrombosis within jugular veins of white female New Zealand rabbits. Blood clot elasticity was noninvasively measured in vivo using the Young's modulus (in kilopascals), on a 2-hour and a 2-week periods after thrombus induction. Monitoring was followed by a necropsy and ex vivo mechanical characterization to validate the existence and elasticity of explanted thrombi.


RESULTS
Stagnant blood in the region of interest underwent clotting and progressive hardening with thrombus aging. The mean Young's moduli varied from 1.0 ± 0.6 kPa (at 10 min) to 5.3 ± 1.6 kPa (at 2 hours), then to 25.0 ± 6.8 kPa (at 14 days) post-surgery. Mean ex vivo moduli of 6.2 ± 0.7 kPa at 2 hours and 29.0 ± 2.4 kPa at 2 weeks agreed with in vivo measures.


CONCLUSIONS
Supersonic imaging of shear waves provides consistent quantitative non-invasive elasticity measurements not available with standard compression ultrasound imaging for diagnosing and following venous thromboembolism. This information translatable to humans could aid in determining whether continued anticoagulant treatment is necessary, especially in the setting of unprovoked venous thromboembolism.
['Mfoumou|Etienne|E|', 'Tripette|Julien|J|', 'Blostein|Mark|M|', 'Cloutier|Guy|G|']
D000818:Animals D001777:Blood Coagulation D055119:Elastic Modulus D005260:Female D007601:Jugular Veins D011817:Rabbits D014463:Ultrasonography D020246:Venous Thrombosis
Ultrasound Venous thrombosis Blood clot hardening Thrombus aging Animal experimentation Elasticity imaging techniques Shear wave elasticity imaging Ultrasonography Young’s modulus