Reproducibility of scanning laser Doppler flowmetry in the rat retina and optic nervehead

Purpose: The purpose of this study is to confirm the reliability of scannin g laser Doppler flowmetry in the rat retina and optic nervehead, and the va lidity of measuring changes of retinal blood flow in rats while: breathing 100% oxygen. Methods: We used a commercially available scanning laser Doppler flowmeter. To ascertain reliability, five consecutive and separate perfusion measurem ents of 12 eyes of 12 anesthetized pigmented rats were performed. To evalua te the validity of the system, repeated measurements were taken in anesthet ized rats breathing room air or 100% oxygen. This series of measurements wa s repeated three times. Results: The reliability coefficients of volume, flow, and velocity in the optic nervehead and the retina ranged from 0.80 to 0.83 and 0.77 to 0.82, r espectively. After the first exposure to oxygen, the measured values of vol ume, flow, and velocity were reduced by an average of 20.9-24.0%, 21.2-28.2 %, and 19.5-24.5%, respectively. After the values returned to the basal con dition, the second and third exposures to oxygen yielded measured values th at were reduced by the same amounts as at the first exposure. Conclusions: Scanning laser Doppler flowmetry provided relatively good reli ability in measurements of blood flow in the rat retina and optic nervehead . This study has indicated the possibility of applying this system to the r at retina. Jpn J Ophthalmol 2000;44:257-262 (C) 2000 Japanese Ophthalmologi cal Society.