OPTIMIZING LOW VELOCITY DOPPLER SONOGRAPHY IN THE ABDOMEN

摘要

They are many instances when examination of low velocity blood flow in the abdomen can be of diagnostic importance. Detection of arterial flow in major arteries is not as technically difficult as that of small arteries such as in the renal cortex. Venous blood flow having a much lower velocity can prove difficult. Detection of portal blood flow is one example. Assessing organ parenchymal perfusion is a newer area under investigation in veterinary medicine. Low velocity blood flow occurs mainly in small veins, venules, and capillaries. The minimum detectable flow velocity is inversely dependent on the ultrasound frequency; when using a 2.5 MHz probe, the minimum detectable flow velocity is 1.5 cm/s. In addition, commercial Doppler devices are typically limited to the frequency below 15 MHz; the minimum detectable flow velocity is around 0.35 cm/s.