ABSTRACT
During the past decades, new tools, such as magnetic resonance imaging and Doppler ultrasound imaging, have been rapidly taken into clinical practice for studying the flow dynamics of the macro-circulation. Meanwhile, techniques for quantifying the microcircu-lation have struggled to become clinically accepted. This includes the use of laser Doppler flowmetry (LDF), an optical technique that is capable of monitoring either spatial or temporal changes in the microcirculation by analyzing the backscattered Doppler-shifted light from a laser-illuminated tissue. Until now, LDF has only been capable of producing non-absolute relative measures, which has limited its clinical acceptance. With a model-based analysis approach, as presented here, this can be overcome, and objective diagnosis of the microcirculation may finally be a part of everyday clinical praxis. The most important advantages with the proposed method are that a quantitative perfusion estimate (% RBC × mm/s) can be extracted and that this measure can be resolved into different speed regions.
