关键词: 血液动力学; 颈动脉; 磁共振成像; 年龄因素

Abstract:

Objective To compare difference of hemodynamic parameters between different age groups using MR imaging combined post-processing techniques. Methods Twenty-two healthy volunteers were divided into 2 groups by age: group 1 (12 adults, aged 20 to 30 years) and group 2 (10 adults, aged 55 to 76 years). Cine Phase-contrast MR imaging was performed to acquire the through-plane flow velocity profiles at 2 cm below the carotid bifucation. Three-dimensional paraboloid model was applied to fit the velocity profiles. The hemodynamic parameters of different-aged groups were calculated and compared. Results Mean wall shear stress (WSS) values of two groups were 0.861±0.209 N/m2 and 0.628±0.179 N/m2 respectively. Statistical significances were observed in mean WSS (P<0.01), WSS in peak-systole (P<0.01) and end-diastole (P<0.01), cross-area (P=0.041), mean velocity (P<0.01), and blood flow rate (P=0.035) of two groups. There was no statistical significance observed in minimal WSS (P=0.226) and maximum WSSTG (P=0.156) between two groups. Conclusion Vascular aging can generate physiological changes in structure and function. Further study on WSS parameters of aged people may provide important hemodynamic information for early prevention and prediction of atherosclerosis

Key words: Hemodynamics; Carotid arteries; Magnetic resonance imaging; Age factors