Development of laser speckle retinal vessels for measuring system

Research Project

Project/Area Number	03557074
Research Category	Grant-in-Aid for Developmental Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	Ophthalmology
Research Institution	The University of Tokyo
Principal Investigator	MASUDA Kanjiro Univ. of Tokyo, Ophthalmology, Prof, 医学部(病), 教授 (60010188)
Co-Investigator(Kenkyū-buntansha)	OGINO Kouji Chofu Laboratory, Kowa Company, Lt Researcher, 研究第一課, 研究員 YAMASHITA Hidetoshi Univ. of Tokyo, Ophthalmology Associate Professor, 医学部(病), 講師 (90158163) 小泉公仁子東京大学, 医学部(病), 助手 (80215152)
Project Period (FY)	1991 – 1992
Project Status	Completed (Fiscal Year 1992)
Budget Amount *help	¥16,600,000 (Direct Cost: ¥16,600,000) Fiscal Year 1992: ¥5,500,000 (Direct Cost: ¥5,500,000) Fiscal Year 1991: ¥11,100,000 (Direct Cost: ¥11,100,000)
Keywords	Laser speckle phenomenon / retinal blood flow retinal blood vessel diameter / laser / retinal blood flow velocity / image sensor / イメージセンサ / レ-ザ-スペックル現象 / レ-ザ-
Research Abstract	We developed an laser speckle velocimeter in which the laser speckle phenomenon was applied to the measurement of the blood flow velocity in human retinal vessels. A linear relationship between the actual blood flow velocities in glass capillary tubes and the Measured values. In an experiment in which we measured the blood flow velocities of 173 human retinal veins (of which diameter ranged from 62 mum to 186 mum) in 28 eyes of 16 normal volunteers, the blood flow velocities ranged from 1.48 mm/s to 32.5 mm/s. Concerning the relationship between the vessel diameter (D) and the blood flow velocity (V) and blood flow rate (F), linear regression analysis of the measured data showed that logV=[0.490.08logD+[0.070.16 and logF= [2.490.08logD-[4.260.16(meanSE). As the next step, we included a real-time retinal blood vessel diameter measuring apparatus in the laser speckle velocimeter. The measurement of the vessel diameter and the of blood flow velocity could be performed at the same time. The reproducibility and accuracy of the apparatus was examined by measuring the width of the slits with 8 different widths on a chart paper, The reproducibility was 0.1600.083%(MeanSD) in coefficients of variance and the correlation coefficient between the measured values and the actual values was 0.999. The mean which was obtained by the method were within the range of 1.771.26%(Mean>:) of the actual values. The blood flow diameters of 40 eyes of 20 normal volunteers were measured by this method and the microscopic method. Hence the reproducibility of the microscopy method was 7.25.4% (MeanSD)in coefficients of variance, that of the image sensor method was 3.142.73%(Mean*SD). The correlation coefficient between those values were 0.835.