Philipp Berg1, Oliver Beuing2. 1. Laboratory of Fluid Dynamics and Technical Flows, University of Magdeburg "Otto von Guericke", Universitätsplatz 2, 39106, Magdeburg, Germany. berg@ovgu.de. 2. Institute of Neuroradiology, University Hospital Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany.
Abstract
PURPOSE: Despite numerous studies addressing the rupture risk of intracranial aneurysms that have been published, the assessment thereof still remains challenging. Image-based simulations enable a precise prediction of patient-specific blood flow information. However, those approaches normally consider only small segments of the complete cerebral vasculature. METHODS: To test the validity of the consideration of single aneurysms in one computational setup, domains of the complete anterior and posterior circulations with multiple intracranial aneurysms (MIA) were simulated. Six patients with MIA were investigated, while 3D surfaces of eleven unruptured and six ruptured aneurysms were segmented. The segmentations were used for the determination of morphological parameters and also for image-based blood flow simulations used to characterize the hemodynamic properties of each aneurysm. RESULTS: In the geometric comparison, neck aspect ratios of unruptured and ruptured aneurysms did not differ significantly. In contrast, size ratios, aspect ratios, surface areas, volumes, and non-sphericity indices were significantly higher in the ruptured cases. The analysis of hemodynamic parameters demonstrated that in each patient, the ruptured aneurysm exhibited the lowest averaged wall shear stresses and highest oscillatory shears. Unstable flow was also detected in ruptured aneurysms based on increased oscillatory velocity. CONCLUSION: In this small study involving patients with MIA, different morphologies and flow patterns were observed between ruptured and unruptured aneurysms. The analysis of the hemodynamics in such patients revealed a good agreement with studies that only considered single malformations. Additionally, complex flow patterns are detected in ruptured cases, which require deeper investigation.
PURPOSE: Despite numerous studies addressing the rupture risk of intracranial aneurysms that have been published, the assessment thereof still remains challenging. Image-based simulations enable a precise prediction of patient-specific blood flow information. However, those approaches normally consider only small segments of the complete cerebral vasculature. METHODS: To test the validity of the consideration of single aneurysms in one computational setup, domains of the complete anterior and posterior circulations with multiple intracranial aneurysms (MIA) were simulated. Six patients with MIA were investigated, while 3D surfaces of eleven unruptured and six ruptured aneurysms were segmented. The segmentations were used for the determination of morphological parameters and also for image-based blood flow simulations used to characterize the hemodynamic properties of each aneurysm. RESULTS: In the geometric comparison, neck aspect ratios of unruptured and ruptured aneurysms did not differ significantly. In contrast, size ratios, aspect ratios, surface areas, volumes, and non-sphericity indices were significantly higher in the ruptured cases. The analysis of hemodynamic parameters demonstrated that in each patient, the ruptured aneurysm exhibited the lowest averaged wall shear stresses and highest oscillatory shears. Unstable flow was also detected in ruptured aneurysms based on increased oscillatory velocity. CONCLUSION: In this small study involving patients with MIA, different morphologies and flow patterns were observed between ruptured and unruptured aneurysms. The analysis of the hemodynamics in such patients revealed a good agreement with studies that only considered single malformations. Additionally, complex flow patterns are detected in ruptured cases, which require deeper investigation.
Authors: H Rajabzadeh-Oghaz; J Wang; N Varble; S-I Sugiyama; A Shimizu; L Jing; J Liu; X Yang; A H Siddiqui; J M Davies; H Meng Journal: AJNR Am J Neuroradiol Date: 2019-10-24 Impact factor: 3.825
Authors: Sylvia Saalfeld; Philipp Berg; Annika Niemann; Maria Luz; Bernhard Preim; Oliver Beuing Journal: Int J Comput Assist Radiol Surg Date: 2018-08-29 Impact factor: 2.924
Authors: Philipp Berg; Samuel Voß; Gábor Janiga; Sylvia Saalfeld; Aslak W Bergersen; Kristian Valen-Sendstad; Jan Bruening; Leonid Goubergrits; Andreas Spuler; Tin Lok Chiu; Anderson Chun On Tsang; Gabriele Copelli; Benjamin Csippa; György Paál; Gábor Závodszky; Felicitas J Detmer; Bong J Chung; Juan R Cebral; Soichiro Fujimura; Hiroyuki Takao; Christof Karmonik; Saba Elias; Nicole M Cancelliere; Mehdi Najafi; David A Steinman; Vitor M Pereira; Senol Piskin; Ender A Finol; Mariya Pravdivtseva; Prasanth Velvaluri; Hamidreza Rajabzadeh-Oghaz; Nikhil Paliwal; Hui Meng; Santhosh Seshadhri; Sreenivas Venguru; Masaaki Shojima; Sergey Sindeev; Sergey Frolov; Yi Qian; Yu-An Wu; Kent D Carlson; David F Kallmes; Dan Dragomir-Daescu; Oliver Beuing Journal: Int J Comput Assist Radiol Surg Date: 2019-05-03 Impact factor: 2.924
Authors: Naomi Larsen; Charlotte Flüh; Sylvia Saalfeld; Samuel Voß; Georg Hille; David Trick; Fritz Wodarg; Michael Synowitz; Olav Jansen; Philipp Berg Journal: Neuroradiology Date: 2020-07-17 Impact factor: 2.804
Authors: Sylvia Saalfeld; Janneck Stahl; Jana Korte; Laurel Morgan Miller Marsh; Bernhard Preim; Oliver Beuing; Yurii Cherednychenko; Daniel Behme; Philipp Berg Journal: Front Neurol Date: 2022-01-24 Impact factor: 4.003