OBJECTIVE: Biomechanically, rupture of an Abdominal Aortic Aneurysm (AAA) occurs when the stress acting on the wall due to the blood pressure, exceeds the strength of the wall. Peak wall stress estimations, based on CT reconstruction, may be prone to observer variation. This study focuses on the robustness and reproducibility of AAA wall stress assessment and the relation with geometrical features of the AAA. METHODS: The AAAs of twenty patients were reconstructed by three operators. Both the peak and 99-percentile stress were used for intra- and inter-operator variability using the intraclass correlation coefficient (ICC). A regression analysis was performed to relate the stress parameters with the maximum diameter. Outliers were analyzed by their geometrical characteristics. RESULTS: The intra-operator ICC was 0.73-0.79 for the peak stress and 0.94 for the 99-percentile stress. The inter-operator ICC was 0.71 for the peak stress and 0.95 for the 99-percentile stress. A significant linear relation with the diameter was found only for the 99-percentile stress. CONCLUSIONS: The 99-percentile stress is more reproducible than peak wall stress. A significant relation between wall stress and diameter was found. Other geometrical features had no statistical relation with high stress.
OBJECTIVE: Biomechanically, rupture of an Abdominal Aortic Aneurysm (AAA) occurs when the stress acting on the wall due to the blood pressure, exceeds the strength of the wall. Peak wall stress estimations, based on CT reconstruction, may be prone to observer variation. This study focuses on the robustness and reproducibility of AAA wall stress assessment and the relation with geometrical features of the AAA. METHODS: The AAAs of twenty patients were reconstructed by three operators. Both the peak and 99-percentile stress were used for intra- and inter-operator variability using the intraclass correlation coefficient (ICC). A regression analysis was performed to relate the stress parameters with the maximum diameter. Outliers were analyzed by their geometrical characteristics. RESULTS: The intra-operator ICC was 0.73-0.79 for the peak stress and 0.94 for the 99-percentile stress. The inter-operator ICC was 0.71 for the peak stress and 0.95 for the 99-percentile stress. A significant linear relation with the diameter was found only for the 99-percentile stress. CONCLUSIONS: The 99-percentile stress is more reproducible than peak wall stress. A significant relation between wall stress and diameter was found. Other geometrical features had no statistical relation with high stress.
Authors: Wei Wu; Balaji Rengarajan; Mirunalini Thirugnanasambandam; Shalin Parikh; Raymond Gomez; Victor De Oliveira; Satish C Muluk; Ender A Finol Journal: Ann Biomed Eng Date: 2019-04-08 Impact factor: 3.934
Authors: Rohini Retarekar; Manasi Ramachandran; Benjamin Berkowitz; Robert E Harbaugh; David Hasan; Robert H Rosenwasser; Christopher S Ogilvy; Madhavan L Raghavan Journal: Comput Methods Biomech Biomed Engin Date: 2014-02-07 Impact factor: 1.763
Authors: Derek P Nathan; Chun Xu; Ted Plappert; Benoit Desjardins; Joseph H Gorman; Joseph E Bavaria; Robert C Gorman; Krishnan B Chandran; Benjamin M Jackson Journal: Ann Thorac Surg Date: 2011-08-25 Impact factor: 4.330