BOLD delay times using group delay in sickle cell disease

Julie Coloigner (1) , Chau Vu (1) , Adam Bush (2, 1) , Matt Borzage (1) , Vidya Rajagopalan (1) , Natasha Leporé (1) , John Wood

1 Children’s Hospital Los Angeles [Los Angeles]
2 Department of Cardiology

Sickle cell disease (SCD) is an inherited blood disorder that effects red blood cells, which can lead to vasoocclu-sion, ischemia and infarct. This disease often results in neurological damage and strokes, leading to morbidity and mortality. Functional Magnetic Resonance Imaging (fMRI) is a non-invasive technique for measuring and mapping the brain activity. Blood Oxygenation Level-Dependent (BOLD) signals contain also information about the neurovascular coupling, vascular reactivity, oxygenation and blood propagation. Temporal relationship between BOLD fluctuations in different parts of the brain provides also a mean to investigate the blood delay information. We used the induced desaturation as a label to profile transit times through different brain areas, reflecting oxygen utilization of tissue. In this study, we aimed to compare blood flow propagation delay time between these patients and healthy subjects in areas vascularized by anterior, middle and posterior cerebral arteries. At first, BOLD changes in these areas were almost simultaneous and shorter in the SCD patients, because of their increased brain blood flow. Secondly, the analysis of a patient with a stenosis on the anterior cerebral artery indicated that signal of the area vascularized by this artery lagged the MCA signal. These findings suggested that sickle cell disease causes blood propagation modifications, and these changes could be used as a biomarker of vascular damage.

Mots clés: Functional magnetic resonance imaging; desaturation; group delay; sickle cell disease

Domaines: Imagerie médicale

Julie Coloigner, Chau Vu, Adam Bush, Matt Borzage, Vidya Rajagopalan, et al.. BOLD delay times using group delay in sickle cell disease. SPIE Medical Imaging, Feb 2016, San Diego, United States. ⟨10.1117/12.2217263⟩. ⟨hal-01710721⟩