Laserflowgraphy: a new visual blood flow meter utilizing a dynamic laser speckle effect.

We developed a visual laser blood flow meter that is capable of providing two-dimensional color graphic representations of blood flow distribution for a given area by utilizing a dynamic laser speckle effect. The device is called the laserflowgraph. The principle and configuration of this flowmeter, comparison with the 133Xe clearance method, difference from thermography, and clinical uses of this flowmeter in flap monitoring are presented. Flow level of the laserflowgraph was significantly correlated with blood flow rate determined by 133Xe clearance in observations on the forearms of normal volunteers. The laserflowgraph reflected blood flow through the region between the skin surface and the deeper region of the papillary layer of the dermis. The laserflowgraph is a highly useful, practical, and reliable tool for assessing cutaneous blood flow and is expected to be applicable to various clinical fields.