Shintaro Nakajima1,2, Shinichiro Sugiyama3, Hidenori Oishi4,5, Kenichi Sato6, Yasushi Matsumoto6, Kuniyasu Niizuma3,7,8, Miki Fujimura9, Teiji Tominaga3. 1. Department of Neuroendovascular Therapy, Kohnan Hospital, Sendai, Japan. snnakaji@juntendo.ac.jp. 2. Department of Neurosurgery, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan. snnakaji@juntendo.ac.jp. 3. Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan. 4. Department of Neurosurgery, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan. 5. Department of Neuroendovascular Therapy, Juntendo University Faculty of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan. 6. Department of Neuroendovascular Therapy, Kohnan Hospital, Sendai, Japan. 7. Department of Neurosurgical Engineering and Translational Neuroscience, Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan. 8. Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan. 9. Department of Neurosurgery, Kohnan Hospital, Sendai, Japan.
Abstract
PURPOSE: Recent computational fluid dynamics (CFD) studies have demonstrated the concurrence of atherosclerotic changes in regions exposed to prolonged blood residence. In this proof-of-concept study, we investigated a small but homogeneous cohort of large, cavernous carotid aneurysms (CCAs) to establish the clinical feasibility of CFD analysis in treatment planning, based on the association between pathophysiology and hemodynamics. METHODS: This study included 15 patients with individual large CCAs. We identified calcifications, which indicated atherosclerotic changes, using the masking data of digital subtraction angiography. We conducted a CFD simulation under patient-specific inlet flow rates measured using magnetic resonance (MR) velocimetry. In the post-CFD analysis, we calculated the blood residence time ([Formula: see text]) and segmented the surface exposed to blood residence time over 1 s ([Formula: see text]). We measured the decrease in volume after flow diversion using the original time-of-flight MR angiography data. RESULTS: Calcifications were observed in the region with [Formula: see text]. In addition, the ratio of [Formula: see text] to the surface of the aneurysmal domain exhibited a negative relationship with the rate of volume reduction at the 6- and 12-month follow-ups. Post-CFD visualization demonstrated that intra-aneurysmal swirling flow prolonged blood residence time under the condition of a small inlet flow rate, when compared to the aneurysmal volume. CONCLUSION: The results of this study suggest the usefulness of CFD analysis for the diagnosis of atherosclerotic changes in large CCAs that may affect the therapeutic response after flow diversion.
PURPOSE: Recent computational fluid dynamics (CFD) studies have demonstrated the concurrence of atherosclerotic changes in regions exposed to prolonged blood residence. In this proof-of-concept study, we investigated a small but homogeneous cohort of large, cavernous carotid aneurysms (CCAs) to establish the clinical feasibility of CFD analysis in treatment planning, based on the association between pathophysiology and hemodynamics. METHODS: This study included 15 patients with individual large CCAs. We identified calcifications, which indicated atherosclerotic changes, using the masking data of digital subtraction angiography. We conducted a CFD simulation under patient-specific inlet flow rates measured using magnetic resonance (MR) velocimetry. In the post-CFD analysis, we calculated the blood residence time ([Formula: see text]) and segmented the surface exposed to blood residence time over 1 s ([Formula: see text]). We measured the decrease in volume after flow diversion using the original time-of-flight MR angiography data. RESULTS: Calcifications were observed in the region with [Formula: see text]. In addition, the ratio of [Formula: see text] to the surface of the aneurysmal domain exhibited a negative relationship with the rate of volume reduction at the 6- and 12-month follow-ups. Post-CFD visualization demonstrated that intra-aneurysmal swirling flow prolonged blood residence time under the condition of a small inlet flow rate, when compared to the aneurysmal volume. CONCLUSION: The results of this study suggest the usefulness of CFD analysis for the diagnosis of atherosclerotic changes in large CCAs that may affect the therapeutic response after flow diversion.
Authors: J R Cebral; F Detmer; B J Chung; J Choque-Velasquez; B Rezai; H Lehto; R Tulamo; J Hernesniemi; M Niemela; A Yu; R Williamson; K Aziz; S Shakur; S Amin-Hanjani; F Charbel; Y Tobe; A Robertson; J Frösen Journal: AJNR Am J Neuroradiol Date: 2019-02-07 Impact factor: 3.825
Authors: David A Steinman; Jaques S Milner; Chris J Norley; Stephen P Lownie; David W Holdsworth Journal: AJNR Am J Neuroradiol Date: 2003-04 Impact factor: 3.825