Retinal oxygen extraction in humans.
Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal blood flow was 44.3 ± 9.0 μl/min during baseline and decreased to 18.7 ± 4.2 μl/min during 100% oxygen breathing (P < 0.001) resulting in a pronounced decrease in retinal oxygen extraction from 2.33 ± 0.51 μl(O2)/min to 0.88 ± 0.14 μl(O2)/min during breathing of 100% oxygen. The method presented in this paper may have significant potential to study oxygen metabolism in hypoxic retinal diseases such as diabetic retinopathy.
Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
René M
RM
Werkmeister
Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.|Department of Clinical Pharmacology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
Doreen
D
Schmidl
Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.|Institute of Applied Physics, Vienna University of Technology, Wiedner Hauptstr, 8-10, 1040 Vienna, Austria.
Gerold
G
Aschinger
Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.|Institute of Applied Physics, Vienna University of Technology, Wiedner Hauptstr, 8-10, 1040 Vienna, Austria.
Veronika
V
Doblhoff-Dier
Department of Clinical Pharmacology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
Stefan
S
Palkovits
Department of Clinical Pharmacology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
Magdalena
M
Wirth
Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
Gerhard
G
Garhöfer
Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA.|Department of Ophthalmology, Northwestern University, Chicago, IL 60611, USA.|Department of Neurobiology and Physiology, Northwestern University, Evanston, IL 60208.
Robert A
RA
Linsenmeier
Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
Rainer A
RA
Leitgeb
Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.|Department of Clinical Pharmacology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
Leopold
L
Schmetterer
D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D001784:Blood Gas Analysis; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D017078:Laser-Doppler Flowmetry; D008297:Male; D010100:Oxygen / Q000032:analysis*; D011859:Radiography; D012039:Regional Blood Flow / Q000502:physiology; D012160:Retina / Q000737:chemistry / Q000378:metabolism*; D012171:Retinal Vessels / Q000000981:diagnostic imaging; D013053:Spectrophotometry; D041623:Tomography, Optical Coherence; D055815:Young Adult
D010100:Oxygen