[Foveal cone densitometer and changes in foveal cone pigments with aging].
A foveal cone densitometer was built for measuring the kinetics of foveal cone pigments in human eyes. The light from a 500-W xenon lamp was divided into reference, measuring, and bleaching beams, and projected through an optical fiber leading to a modified fundus camera. After the light was projected into the ocular fundus, the reflected light (central 1 degree) was measured by a photomultiplier and the regeneration time and the two-way density were abstracted from the records. The two-way density, which is the decadic logarithm of the measuring-reference beam ratio under bleached conditions divided by the measuring-reference beam ratio under dark conditions, eliminated the artifacts caused by eye movement of blink. Reliable curves were obtained in 45 eyes out of 53 healthy Japanese subjects (age range, 9 to 82 years). The mean +/- standard deviation SD of the two-way density (log) and the time constant (sec) were 0.34 +/- 0.09 and 139.9 +/- 79.3, respectively. The time constant significantly increased with aging.
Saito
A
A
Department of Ophthalmology, Nagoya University School of Medicine, Aichi-ken, Japan.
Miyake
Y
Y
Wang
J X
JX
Yagasaki
K
K
Matsumoto
Y
Y
Horio
N
N
Horiguchi
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism*; D002648:Child; D003720:Densitometry; D005260:Female; D005584:Fovea Centralis / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017949:Retinal Cone Photoreceptor Cells / Q000378:metabolism*; D012168:Retinal Pigments / Q000378:metabolism*
D012168:Retinal Pigments