Capillary Blood Cell Velocity Measurement of the Nailfold in vivo

• Main Authors: Li Chin Kuei, 李錦奎
• Other Authors: Yio Wha Shau
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/24061933127183390203

碩士 === 國立臺灣大學 === 應用力學研究所 === 92 === An experimental program is conducted to observe the real-time moving trace of the red blood cells (RBCs) in the capillaries. Under the IR laser scanning, along the capillaries we observed that the RBCs formed gray spots that moved sequentially downstream with intermittent clear intervals. By choosing a M-line trace along the capillary, the movement of the RBCs alone it straightened path forms a motion map that gives y-axis as the streamwise location and x-axis as the time. Thus, the time rate of change of the each RBC movement (slope of motion map), time history of RBC velocity, can be quantified. The RBC velocity in the normal human is about 0.15 ~ 1.1 mms-1, and the average velocity is 0.252 ±0.01 mms-1, which agrees well with the literature. For capillaries of various diameters, there velocities are different. Also, we found that each capillary has different response to temperature, and this phenomenon behaved like the Lewis irregular effect. In this experiment, for those capillaries that with twisted shape their fluctuation in velocity cycle were higher than others. The present method provided a less expensive system than laser Doppler and more suitable for low flow rate. Since the capillaries were measured relatively parallel to the skin for some period, the RBC particle traces and the corresponding velocity gave a better view of the vessel wall interaction, path irregularity, and upstream influence of pulsation. The present apparatus can be used for the capillaries on the nail fold of the foot, thus its clinical applications to diabetic foot study is feasible.