Assessment of laser speckle flowgraphy: Development of novel cutaneous blood flow measurement technique

Currently, there is no measurement device capable of comparing cutaneous blood flow among individuals. Thus, we experimentally prepared a laser speckle flowgraphy (LSFG) device, and investigated whether it can accurately measure cutaneous blood flow. The range in linearity of the positive correlation between the uniform circular motion speed (mm/sec) and mean blur rate (MBR), which is an index of cutaneous blood flow measured using LSFG, was investigated using a speed calibrator (Opal glass plate: OGP). Using strain-gauge plethysmography (SPG), measures the absolute value of blood flow (mL/min/100g), and LSFG, cutaneous blood flow was measured in the left finger in 50 healthy adults, and the correlation between the values measured by the two methods was investigated. An index of LSFG, MBR, was positively correlated with the turntable speed within a range from 10 to 450 mm/sec, suggesting that the MBR value may be useful as an index of the speed within this range. When cutaneous blood flow was measured at the fingertip using SPG and LSFG, a significant positive correlation was noted between the two measurement methods, suggesting that the MBR value with LSFG is a useful index of cutaneous blood flow. It is suggested that LSFG is a useful device for cutaneous blood flow evaluation because it allows comparison of cutaneous blood flow among individuals without the limitation of the measurement region noninvasively as well as continuously. Its applications in medical care and esthetic fields are expected.