Dynamic Evaluation of Vascular Remodeling and Aneurysm Progression Using Blood-Pool Contrast-Enhanced In Vivo...

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Vascular Surgery

Background:

• Assessing vascular graft remodeling and aneurysm progression in small animal models is crucial but limited by non-terminal methods.
• Current techniques often rely on post-mortem analyses at single time points, hindering longitudinal studies.

Purpose of the Study:

• To evaluate contrast-enhanced micro-computed tomography (micro-CT) as a tool for longitudinal, in vivo monitoring of vascular grafts in rodents.
• To compare the efficacy of molecular versus nanoparticle-based contrast agents for vascular imaging in this model.

Main Methods:

• A rodent pulmonary vascular graft model was established by implanting a pulmonary artery segment into the abdominal aorta.
• Contrast-enhanced micro-CT was performed using both a molecular iodinated contrast agent and a nanoparticle-based blood-pool agent.
• Imaging data were analyzed for vascular opacification, graft morphology, and aneurysm development over time.

Main Results:

• The molecular contrast agent showed rapid clearance, leading to insufficient vascular opacification for graft assessment.
• The nanoparticle-based agent provided prolonged vascular enhancement, allowing for high-resolution imaging.
• This enabled quantitative, longitudinal assessment of vascular graft remodeling and aneurysm progression in vivo.

Conclusions:

• Contrast-enhanced micro-CT, particularly with nanoparticulate blood-pool contrast agents, offers a viable non-terminal method for longitudinal evaluation of vascular grafts in rodents.
• This technique overcomes the limitations of traditional post-mortem analyses, enabling quantitative monitoring of graft remodeling and aneurysm development.
• This advancement supports more comprehensive research into vascular graft performance and disease progression.