A new laser Doppler system for examining optic nerve head circulation

A new laser Doppler system for the noninvasive examination of the human optic nerve head microcirculation is described. The electro-optical component of the system consists of a retinal camera modified with laser input optics and a fiber optic light detection system for collection of the Doppler-shifted scattered light. Data acquisition is carried out in real time under computer control. Automated analysis of the data provides a quantitative measure of the speed of blood cells flowing through the capillaries of the optic nerve head. Unlike previous systems, this system provides results within a few minutes following data acquisition. It is thus appropriate for use in a clinical setting. Analysis of multiple measurements on a patient shows a coefficient of variation of 8.9%. © 1998 Society of Photo-Optical Instrumentation Engineers.