A feasibility study of elastography on abdominal aneurysms
Notice bibliographique
Résumé
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.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,001 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,001 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».