A physiological model for interpretation of arterial spin labeling reactive hyperemia of calf muscles
نویسندگان
چکیده
To characterize and interpret arterial spin labeling (ASL) reactive hyperemia of calf muscles for a better understanding of the microcirculation in peripheral arterial disease (PAD), we present a physiological model incorporating oxygen transport, tissue metabolism, and vascular regulation mechanisms. The model demonstrated distinct effects between arterial stenoses and microvascular dysfunction on reactive hyperemia, and indicated a higher sensitivity of 2-minute thigh cuffing to microvascular dysfunction than 5-minute cuffing. The recorded perfusion responses in PAD patients (n = 9) were better differentiated from the normal subjects (n = 7) using the model-based analysis rather than characterization using the apparent peak and time-to-peak of the responses. The analysis results suggested different amounts of microvascular disease within the patient group. Overall, this work demonstrates a novel analysis method and facilitates understanding of the physiology involved in ASL reactive hyperemia. ASL reactive hyperemia with model-based analysis may be used as a noninvasive microvascular assessment in the presence of arterial stenoses, allowing us to look beyond the macrovascular disease in PAD. A subgroup who will have a poor prognosis after revascularization in the patients with critical limb ischemia may be associated with more severe microvascular diseases, which may potentially be identified using ASL reactive hyperemia.
منابع مشابه
Evaluation of peak skeletal muscle perfusion in the lower extremities of athletes using arterial spin labeling
Background Arterial spin labeling (ASL) magnetic resonance imaging (MRI) allows for evaluation of skeletal muscle perfusion and provides a non-invasive index of vascular function. Previous studies have investigated ASL responses during reactive hyperemia in healthy subjects and patients with peripheral vascular disease; however, ASL has not been applied for assessment of tissue perfusion in ath...
متن کاملASL demonstrates higher and more homogenous calf muscle perfusion with post-occlusion hyperemia than with exercise
Background Pulsed arterial spin labeling (PASL) is a non-contrast MRI technique capable of quantifying calf muscle perfusion with comparable accuracy to contrast enhancedMRI perfusion in normal subjects and peripheral arterial disease (PAD) patients. Peak perfusion can be achieved with exercise or during post-occlusion hyperemia. However, exercise stress may underestimate peak perfusion because...
متن کاملProtocol optimization and physiological specificity of ASL-measured reactive hyperemia in skeletal muscle
Background Evidence suggests that microvascular function may be compromised in Peripheral Arterial Disease (PAD) due to associated endothelial dysfunction. While revascularization is recommended for PAD patients with macrovascular occlusions, a solution for endothelial dysfunction remains unavailable. For a possible endothelium-targeted therapy to be applied, the burden of endothelial dysfuncti...
متن کاملArterial spin labeling perfusion cardiovascular magnetic resonance of the calf in peripheral arterial disease: cuff occlusion hyperemia vs exercise
BACKGROUND Assessment of calf muscle perfusion requires a physiological challenge. Exercise and cuff-occlusion hyperemia are commonly used methods, but it has been unclear if one is superior to the other. We hypothesized that post-occlusion calf muscle perfusion (Cuff) with pulsed arterial spin labeling (PASL) cardiovascular magnetic resonance (CMR) at 3 Tesla (T) would yield greater perfusion ...
متن کاملValidation of diffuse correlation spectroscopy for muscle blood flow with concurrent arterial spin labeled perfusion MRI.
Calf blood flow was measured simultaneously in healthy human subjects (n = 7) during cuff inflation and deflation using near-infrared diffuse correlation spectroscopy (DCS) and arterial spin labeled perfusion MRI (ASL-MRI). The DCS and ASL-MRI data exhibited highly correlated absolute and relative dynamic flow responses in each individual (p < 0.001). Peak flow variations during hyperemia were ...
متن کامل