New, angle-independent, low-cost Doppler system to measure blood flow

Vaginal microcirculation: Non-invasive anatomical examination of the micro-vessel architecture, tortuosity and capillary density

“…Median age of the nine volunteers was 22 years (range [19][20][21][22][23]. Six volunteers used oral contraception.…”

“…Doppler ultrasound uses standard ultrasound methods to provide information about the speed and direction of blood flow through the vessel being evaluated. Laser Doppler flowmetry is a non‐invasive method of assessing microcirculatory blood flow, it can detect flow in capillaries as small as 11 µm and as deep as 2 mm below the skin surface . However, these techniques do not provide direct visualization of the microcirculation and often flow is expressed in arbitrary units.…”

“…Laser Doppler flowmetry is a non-invasive method of assessing microcirculatory blood flow, it can detect flow in capillaries as small as 11 mm and as deep as 2 mm below the skin surface. 22 However, these techniques do not provide direct visualization of the microcirculation and often flow is expressed in arbitrary units. Dynamic MRI provides excellent visualization of anatomic detail through serial images, however, MRI is expensive, time consuming, and machine availability can be a problem.…”

A New Angle-Independent Doppler Ultrasonic Device for Assessment of Blood Flow Volume in the Extracranial Internal Carotid Artery

“…17,22 Eventually, multiple ultrasound beam systems have emerged as alternative solutions for angle dependency and have been shown to achieve more accurate measurements of blood flow velocity. 19,[23][24][25] Even if an accurate velocity measurement is assumed, however, it will not allow calculation of the flow volume without being spatially and temporarily integrated. 14 Angle dependency, indeed, is not the only contributor to the inaccuracy in the measurement of flow velocity by ultrasonic systems.…”

Vaginal Laser Doppler Flowmetry Pre- and Posthysterectomy

“…From the Doppler spectral shift, the RBC velocity, volume and flow can be calculated. The method is accurate enough to detect flow in capillaries as small as 11 micrometers up to 2 mm below the skin surface (Skadalny et al, 1998).…”