Emrah Akkoyun1, Hamidreza Gharahi2, Sebastian T Kwon3, Byron A Zambrano2, Akshay Rao2, Aybar C Acar1, Whal Lee4, Seungik Baek5. 1. Department of Health Informatics, Graduate School of Informatics, Middle East Technical University, Dumlupinar Bulvari #1, 06800 Cankaya, Ankara, Turkey. 2. Department of Mechanical Engineering, Michigan State University, 2457 Engineering Building, East Lansing, MI 48824, USA. 3. Department of Anesthesiology and Perioperative Medicine, UCLA David Geffen School of Medicine, 757 Westwood Blvd., Los Angeles, CA 90095, USA. 4. Department of Radiology, Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul, Republic of Korea. 5. Department of Mechanical Engineering, Michigan State University, 2457 Engineering Building, East Lansing, MI 48824, USA. Electronic address: sbaek@egr.msu.edu.
Abstract
OBJECTIVE: The maximum diameter measurement of an abdominal aortic aneurysm (AAA), which depends on orthogonal and axial cross-sections or maximally inscribed spheres within the AAA, plays a significant role in the clinical decision making process. This study aims to build a total of 21 morphological parameters from longitudinal CT scans and analyze their correlations. Furthermore, this work explores the existence of a "master curve" of AAA growth, and tests which parameters serve to enhance its predictability for clinical use. METHODS: 106 CT scan images from 25 Korean AAA patients were retrospectively obtained. We subsequently computed morphological parameters, growth rates, and pair-wise correlations, and attempted to enhance the predictability of the growth for high-risk aneurysms using non-linear curve fitting and least-square minimization. RESULTS: An exponential AAA growth model was fitted to the maximum spherical diameter, as the best representative of the growth among all parameters (r-square: 0.94) and correctly predicted to 15 of 16 validation scans based on a 95% confidence interval. AAA volume expansion rates were highly correlated (r=0.75) with thrombus accumulation rates. CONCLUSIONS: The exponential growth model using spherical diameter provides useful information about progression of aneurysm size and enables AAA growth rate extrapolation during a given surveillance period.
OBJECTIVE: The maximum diameter measurement of an abdominal aortic aneurysm (AAA), which depends on orthogonal and axial cross-sections or maximally inscribed spheres within the AAA, plays a significant role in the clinical decision making process. This study aims to build a total of 21 morphological parameters from longitudinal CT scans and analyze their correlations. Furthermore, this work explores the existence of a "master curve" of AAA growth, and tests which parameters serve to enhance its predictability for clinical use. METHODS: 106 CT scan images from 25 Korean AAA patients were retrospectively obtained. We subsequently computed morphological parameters, growth rates, and pair-wise correlations, and attempted to enhance the predictability of the growth for high-risk aneurysms using non-linear curve fitting and least-square minimization. RESULTS: An exponential AAA growth model was fitted to the maximum spherical diameter, as the best representative of the growth among all parameters (r-square: 0.94) and correctly predicted to 15 of 16 validation scans based on a 95% confidence interval. AAA volume expansion rates were highly correlated (r=0.75) with thrombus accumulation rates. CONCLUSIONS: The exponential growth model using spherical diameter provides useful information about progression of aneurysm size and enables AAA growth rate extrapolation during a given surveillance period.
Authors: Elliot L Chaikof; David C Brewster; Ronald L Dalman; Michel S Makaroun; Karl A Illig; Gregorio A Sicard; Carlos H Timaran; Gilbert R Upchurch; Frank J Veith Journal: J Vasc Surg Date: 2009-10 Impact factor: 4.268
Authors: Anthony R Brady; Simon G Thompson; F Gerald R Fowkes; Roger M Greenhalgh; Janet T Powell Journal: Circulation Date: 2004-06-21 Impact factor: 29.690