title: A combined method to quantify the retinal metabolic rate of oxygen using photoacoustic ophthalmoscopy and optical coherence tomography.
abstract: Quantitatively determining physiological parameters at a microscopic level in the retina furthers the understanding of the molecular pathways of blinding diseases, such as diabetic retinopathy and glaucoma. An essential parameter, which has yet to be quantified noninvasively, is the retinal oxygen metabolic rate (rMRO2). Quantifying rMRO2 is challenging because two parameters, the blood flow rate and hemoglobin oxygen saturation (sO2), must be measured together. We combined photoacoustic ophthalmoscopy (PAOM) with spectral domain-optical coherence tomography (SD-OCT) to tackle this challenge, in which PAOM measured the sO2 and SD-OCT mapped the blood flow rate. We tested the integrated system on normal wild-type rats, in which the measured rMRO2 was 297.86 ± 70.23 nl/minute. This quantitative method may shed new light on both fundamental research and clinical care in ophthalmology in the future.
authors.affiliation: 1] Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA [2] Department of Physics, Harbin Institute of Technology, 92 West Da-Zhi Street Nangang District, Harbin, Heilongjiang 150080, China [3].
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.affiliation: 1] Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA [2].
authors.forename: Qing
authors.initials: Q
authors.lastname: Wei
authors.affiliation: 1] Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA [2].
authors.forename: Wenzhong
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA.
authors.forename: Tan
authors.initials: T
authors.lastname: Liu
authors.affiliation: Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA.
authors.forename: Ji
authors.initials: J
authors.lastname: Yi
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, WI 53792, USA.
authors.forename: Nader
authors.initials: N
authors.lastname: Sheibani
authors.affiliation: Department of Ophthalmology, Northwestern University, Chicago, IL 60611, USA.
authors.forename: Amani A
authors.initials: AA
authors.lastname: Fawzi
authors.affiliation: 1] Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA [2] Department of Ophthalmology, Northwestern University, Chicago, IL 60611, USA [3] Department of Neurobiology and Physiology, Northwestern University, Evanston, IL 60208, USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Linsenmeier
authors.affiliation: Department of Biomedical Engineering, Florida International University, Miami, FL 33174, USA.
authors.forename: Shuliang
authors.initials: S
authors.lastname: Jiao
authors.affiliation: 1] Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA [2] Department of Ophthalmology, Northwestern University, Chicago, IL 60611, USA.
authors.forename: Hao F
authors.initials: HF
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001481:Basal Metabolism / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology; D006454:Hemoglobins / Q000032:analysis; D009887:Ophthalmoscopy / Q000379:methods*; D010100:Oxygen / Q000378:metabolism*; D061088:Photoacoustic Techniques / Q000295:instrumentation / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000378:metabolism*; D041623:Tomography, Optical Coherence / Q000295:instrumentation / Q000379:methods*
chemical_list: D006454:Hemoglobins; D010100:Oxygen