Oximetry of retinal capillaries by multicomponent analysis.
Retinal oximetry of capillaries was performed for early detection of retinal vascular abnormalities, which are caused predominantly by complications of systemic circulatory diseases. As the conventional method for determining absorbance is not applicable to capillaries, multicomponent  analysis was used to estimate the absorbance spectra of the retinal blood vessels. In this analysis, the capillary spectrum was classified as intermediate between those of the retinal arteries and veins, enabling relative estimation of oxygen saturation in the capillaries. This method could  be useful for early recognition of disturbances in the peripheral circulation. Furthermore, a spectroscopic ophthalmoscope system based on the proposed method was developed to examine the human retina. A clinical trial of this system demonstrated that oximetry of the retinal capillaries may  be an improvement over the present diagnosis for patients of malignant hypertension.
Electronics and Photonics Research Institute of AIST, Umezono 1-1-1, Tsukuba 305-8568, Japan. h-furukawa@aist.go.jp
Hiromitsu
H
Furukawa
Hidenobu
H
Arimoto
Tomohiro
T
Shirai
Sotaro
S
Ooto
Masanori
M
Hangai
Nagahisa
N
Yoshimura
D000328:Adult; D002196:Capillaries; D004867:Equipment Design; D005654:Fundus Oculi; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D008297:Male; D019721:Ophthalmoscopes; D010100:Oxygen / Q000097:blood*; D010108:Oxyhemoglobins / Q000032:analysis*; D025341:Principal Component Analysis; D012161:Retinal Artery; D012169:Retinal Vein; D012171:Retinal Vessels / Q000737:chemistry*; D013053:Spectrophotometry / Q000295:instrumentation / Q000379:methods*
D006454:Hemoglobins; D010108:Oxyhemoglobins; D010100:Oxygen