Purchase this article with an account.
M. Nagahara, J. Takayama, Y. Tamaki, A. Tomidokoro, M. Araie; In vivo Measurement of Blood Velocity in Human Major Retinal Arteries using Laser Speckle Method and Laser Doppler Velocimetry: Comparison between the Two Methods . Invest. Ophthalmol. Vis. Sci. 2003;44(13):4959.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: Tissue blood velocity in the choroids or optic nerve head in the living eye could be successfully measured by means of laser speckle method of which details have been previously published 1,2. To measure blood velocity in major retinal vessels using this method, square blur rate (SBR) was introduced as a quantitative index of blurring of a speckle pattern which should parallel the velocity of red blood cells. The purpose of this study is to compare the blood velocity in human major retinal arteries determined by laser speckle method and that by laser Doppler velocimetry (LDV). Methods: First, SBR values obtained from blood flowing in a glass capillary tube (analogue of a retinal artery) were correlated to the diameter of tube, actual blood flow rate, and SBR values obtained from blood flowing in glass capillary tubes underlying that as analogue of a retinal artery (analogue of choroidal blood flow), and a nomogram to calculate in vivo blood velocity in a retinal artery from SBR values obtained in vitro was produced. Second, blood velocity in human major retinal artery was measured in 12 normal human eyes using both laser speckle method and LDV (CLBF model 100, Canon). The measurements were performed twice at the same site at 3-hour intervals. Results: The mean blood velocity in human temporal superior artery with average diameter of 121µm was 41.7(±4.2) mm/sec (SD, N=12) by laser speckle method and 37.7(±6.7) mm/sec with LDV. No inter-group was seen, while inter-group correlation was significant (r=0.59, p=0.023). The coefficient of reproducibility and time needed to complete one measurement averaged 9.5% and 64 sec for laser speckle method and 15.3% and 112 sec for LDV, respectively. Conclusions: Blood velocity in human major retinal artery can be measured by means of laser speckle method with reasonable accuracy and reproducibility. Measurements by this method could be performed more easily and subject-friendly than those by LDV.
This PDF is available to Subscribers Only