Establishing the distribution of cerebrovascular resistance using computational fluid dynamics and 4D flow MRI

• Published in: Scientific reports Vol. 14; no. 1; pp. 14585 - 11
• Main Authors: Vikström, Axel, Holmlund, Petter, Holmgren, Madelene, Wåhlin, Anders, Zarrinkoob, Laleh, Malm, Jan, Eklund, Anders
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 25.06.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 639/766/189; 692/699/75; 692/699/75/593; 692/699/75/593/1353; 692/699/75/593/1370/534; Aged; Angiography; Blood flow; Blood Flow Velocity; Brain - blood supply; Brain - diagnostic imaging; Brain - physiopathology; Carotid stenosis; Carotid Stenosis - diagnostic imaging; Carotid Stenosis - physiopathology; Cerebral blood flow; Cerebral hemispheres; Cerebrovascular Circulation - physiology; Cerebrovascular resistance; Circle of Willis - diagnostic imaging; Circle of Willis - physiopathology; Computational fluid dynamics; Computational neuroscience; Computed tomography; Computed Tomography Angiography - methods; Female; Fluid dynamics; Fluid flow; Hemodynamics; Humanities and Social Sciences; Humans; Hydrodynamics; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Male; Middle Aged; multidisciplinary; Peripheral cerebral territories; Science; Science (multidisciplinary); Stenosis; Stroke; Stroke - diagnostic imaging; Stroke - physiopathology; Territorial behavior; Transient ischemic attack; Vascular Resistance - physiology; Carotid stenosis; Stroke; Computational fluid dynamics; Peripheral cerebral territories; Cerebrovascular resistance
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-65431-4

Cerebrovascular resistance (CVR) regulates blood flow in the brain, but little is known about the vascular resistances of the individual cerebral territories. We present a method to calculate these resistances and investigate how CVR varies in the hemodynamically disturbed brain. We included 48 patients with stroke/TIA (29 with symptomatic carotid stenosis). By combining flow rate (4D flow MRI) and structural computed tomography angiography (CTA) data with computational fluid dynamics (CFD) we computed the perfusion pressures out from the circle of Willis, with which CVR of the MCA, ACA, and PCA territories was estimated. 56 controls were included for comparison of total CVR (tCVR). CVR were 33.8 ± 10.5, 59.0 ± 30.6, and 77.8 ± 21.3 mmHg s/ml for the MCA, ACA, and PCA territories. We found no differences in tCVR between patients, 9.3 ± 1.9 mmHg s/ml, and controls, 9.3 ± 2.0 mmHg s/ml (p = 0.88), nor in territorial CVR in the carotid stenosis patients between ipsilateral and contralateral hemispheres. Territorial resistance associated inversely to territorial brain volume (p < 0.001). These resistances may work as reference values when modelling blood flow in the circle of Willis, and the method can be used when there is need for subject-specific analysis.