OBJECTIVE: Local anatomy and the patient's risk profile independently affect the expansion rate of an abdominal aortic aneurysm. We describe a hybrid method that combines finite element modelling and statistical methods to predict patient-specific aneurysm expansion. METHODS: The 3-D geometry of the aneurysm was imaged with computed tomography. We used finite element methods to calculate wall stress and aneurysm expansion. Expansion rate was adjusted by risk factors obtained from a database of 80 patients. Aneurysm diameters predicted with and without the risk profiles were compared with diameters measured with ultrasound for 11 patients. RESULTS: For this specific group of patients, local anatomy contributed 62% and the risk profile 38% to the aneurysmal expansion rate. Predictions with risk profiles resulted in smaller root mean square errors than predictions without risk profiles (2.9 vs. 4.0 mm, p < 0.01). CONCLUSIONS: This hybrid approach predicted aneurysmal expansion for a period of 30 months with high accuracy. Copyright 2010 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.
OBJECTIVE: Local anatomy and the patient's risk profile independently affect the expansion rate of an abdominal aortic aneurysm. We describe a hybrid method that combines finite element modelling and statistical methods to predict patient-specific aneurysm expansion. METHODS: The 3-D geometry of the aneurysm was imaged with computed tomography. We used finite element methods to calculate wall stress and aneurysm expansion. Expansion rate was adjusted by risk factors obtained from a database of 80 patients. Aneurysm diameters predicted with and without the risk profiles were compared with diameters measured with ultrasound for 11 patients. RESULTS: For this specific group of patients, local anatomy contributed 62% and the risk profile 38% to the aneurysmal expansion rate. Predictions with risk profiles resulted in smaller root mean square errors than predictions without risk profiles (2.9 vs. 4.0 mm, p < 0.01). CONCLUSIONS: This hybrid approach predicted aneurysmal expansion for a period of 30 months with high accuracy. Copyright 2010 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.