{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,25]],"date-time":"2025-09-25T17:08:38Z","timestamp":1758820118168,"version":"3.41.2"},"reference-count":43,"publisher":"ASME International","issue":"10","funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["R15HL087268","R21EB007651","R21EB008804"],"award-info":[{"award-number":["R15HL087268","R21EB007651","R21EB008804"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["asmedigitalcollection.asme.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2016,10,1]]},"abstract":"<jats:p>In this work, we present a novel method for the derivation of the unloaded geometry of an abdominal aortic aneurysm (AAA) from a pressurized geometry in turn obtained by 3D reconstruction of computed tomography (CT) images. The approach was experimentally validated with an aneurysm phantom loaded with gauge pressures of 80, 120, and 140\u2009mm Hg. The unloaded phantom geometries estimated from these pressurized states were compared to the actual unloaded phantom geometry, resulting in mean nodal surface distances of up to 3.9% of the maximum aneurysm diameter. An in-silico verification was also performed using a patient-specific AAA mesh, resulting in maximum nodal surface distances of 8\u2009\u03bcm after running the algorithm for eight iterations. The methodology was then applied to 12 patient-specific AAA for which their corresponding unloaded geometries were generated in 5\u20138 iterations. The wall mechanics resulting from finite element analysis of the pressurized (CT image-based) and unloaded geometries were compared to quantify the relative importance of using an unloaded geometry for AAA biomechanics. The pressurized AAA models underestimate peak wall stress (quantified by the first principal stress component) on average by 15% compared to the unloaded AAA models. The validation and application of the method, readily compatible with any finite element solver, underscores the importance of generating the unloaded AAA volume mesh prior to using wall stress as a biomechanical marker for rupture risk assessment.<\/jats:p>","DOI":"10.1115\/1.4034425","type":"journal-article","created":{"date-parts":[[2016,8,18]],"date-time":"2016-08-18T16:33:31Z","timestamp":1471538011000},"update-policy":"https:\/\/doi.org\/10.1115\/crossmarkpolicy-asme","source":"Crossref","is-referenced-by-count":13,"title":["A Methodology for the Derivation of Unloaded Abdominal Aortic Aneurysm Geometry With Experimental Validation"],"prefix":"10.1115","volume":"138","author":[{"given":"Santanu","family":"Chandra","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, University of Texas at San Antonio, San Antonio, TX 78249"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vimalatharmaiyah","family":"Gnanaruban","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of Texas at San Antonio, San Antonio, TX 78249"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fabian","family":"Riveros","sequence":"additional","affiliation":[{"name":"Aragon Institute of Engineering Research, Universidad de Zaragoza, Zaragoza 50018, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jose F.","family":"Rodriguez","sequence":"additional","affiliation":[{"name":"Aragon Institute of Engineering Research, Universidad de Zaragoza, Zaragoza 50018, Spain;"},{"name":"Department of Chemistry, Materials, and Chemical Engineering \u201cGiulio Natta,\u201d Politecnico di Milano, Milano 20133, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ender A.","family":"Finol","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Texas at San Antonio, EB 3.04.23, One UTSA Circle, San Antonio, TX 78249 e-mail:"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"33","published-online":{"date-parts":[[2016,8,30]]},"reference":[{"issue":"22","key":"2019100603355561300_bib1","doi-asserted-by":"publisher","first-page":"2101","DOI":"10.1056\/NEJMcp1401430","article-title":"Abdominal Aortic Aneurysms","volume":"371","year":"2014","journal-title":"N. 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