Abdominal aortic aneurysm follow-up by shear wave elasticity imaging after endovascular repair in a canine model

Abstract

• SWI has the potential to detect endoleaks in post-EVAR follow-up. • SWI has the potential to characterize thrombus organization in post-EVAR follow-up. • SWI may be combined with DUS in post-EVAR surveillance of endoleak.

Shear wave elasticity imaging for residual endoleak and thrombus characterisation after endoleak embolisation following endovascular aneurysm repair: a canine animal study

“…This imaging technique consistently provided the elastic modulus within the different ROIs. As previously reported in a primary endoleak model, SWI can detect endoleak with a high sensitivity [ 10 ]. In the current study, its potential to detect residual endoleak after embolisation is confirmed.…”

“…SWI was used to observe the evolution of the mechanical property of the thrombus and embolisation agent over time. Endoleak on SWI was defined as the absence of elasticity values within the aneurysm sac outside the stent-graft with the presence of signal on the posterior wall [ 10 ]. Areas without signal on the posterior wall were deemed as non-diagnostic.…”

“…Presence of contrast enhancement on CT scans combined with the presence of a defect in the aneurysm sac on the macroscopic examination was used as the reference standard for endoleak diagnosis [ 10 ].…”

“…To determine stiffness values corresponding to different levels of thrombus organisation, the thrombus was sub-classified in fresh or organised thrombus on the pre-sacrifice examination. To evaluate fresh thrombus maturation over time, ROIs with elasticity values compatible with the presence of a fresh thrombus (in the range of 3–19 kPa as previously reported [ 10 ]) on the one-week SWI examination were segmented and registered on the three-month SWI examination.…”

“…The potential of shear wave imaging (SWI) to detect endoleak and characterise thrombus organisation after EVAR was previously reported in a canine model [ 10 ]. Our goal was to evaluate, always in a canine model, the potential of SWI to characterise aneurysm healing and thrombus maturation over time after endoleak embolisation using embolising gels with or without sclerosing agents.…”