A feasibility study of elastography on abdominal aneurysms
Autor: | Jérémie Fromageau, Jean Raymond, Guy Cloutier, Gilles Soulez, Igor Salazkin, Sophie Lerouge |
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Rok vydání: | 2006 |
Předmět: |
Aorta
education.field_of_study medicine.medical_specialty business.industry medicine.medical_treatment Population Stent medicine.disease Aneurysm medicine.anatomical_structure medicine.artery cardiovascular system medicine Abdomen cardiovascular diseases Implant Radiology Thrombus business education Artery |
Zdroj: | IEEE Ultrasonics Symposium, 2005.. |
Popis: | In this work, the feasibility of the elastography method for the follow-up of abdominal aneurysm (AA) is studied on a canine model. Experiments were performed at different times of the follow-up treatment, before implantation of the Stent Graft (SG), right after implantation, and 3 months later. Data were acquired with an intravascular and an external ultrasound scanners. Several aspects were investigated. First, changes of mechanical properties associated with aneurysms were studied in the aneurysmal wall and the neck region before SG implantation. Secondly, we investigated the feasibility of studying possible changes in arterial wall elasticity due to SG constrain after SG implantation. Finally the healing process in the aneurysmal sac is evaluated after 3 months. The preliminary results showed the possibility to discriminate healthy wall in the neck from aneurysm wall, and the mechanical different behavior of the well-healed aneurysm from a badly healed one. I. INTRODUCTION Abdominal Aortic Aneurysms (AAA) affect between 5 and 7% of the population older than 60 years old in the USA. They are characterized by a permanent dilatation of the aorta due to weakening of its mechanical properties. Their rupture is a ma- jor cause of mortality, responsable for more than 15,000 deaths each year in the USA (http://www.nationmaster.com/graph- T/mor_aor_ane_and_dis). The choice of AAA treatment is based on the risk of rupture, which is calculated based on aneurysm size and growth. Finite element models are a promising way to better determine risks associated with each aneurysm, but mechanical properties are missing. Surgical replacement of the aneurysmal segment is presently the stan- dard treatment but the endovascular treatment with a SG to exclude the aneurysm (Fig.1) offers a less invasive alternative, which allows to reduce surgical risks and time of recovery for patients. Its widespread use is however limited by relatively frequent complications, which mechanisms are still poorly understood. The extent of the pathology prior to treatment, the impact of the treatment on biological and mechanical properties of the vessel wall, and deficient healing of the fresh- formed thrombus around the implant may play significant roles in these complications. Nevertheless, this technique has the advantage to be less invasive and to reduce the immediate rates of mortality, however several drawbacks limit its efficacy in the long term because of the deficient healing around the SG (1). The study of the mechanical behavior of the arterial wall is thus of interest because an aneurysm is characterized by a dilation of the artery associated with changes in its mechanical and biological properties. It would also be of interest to evaluate the SG healing process through an examination of the mechanical properties of fresh-formed thrombus between the SG and the aneurysm. Then, elastography seems to be a good modality to provide such extra informations, both for the diagnosis as well as for the treatment follow up. |
Databáze: | OpenAIRE |
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