title: Total Retinal Blood Flow in a Nonhuman Primate Optic Nerve Transection Model Using Dual-Beam Bidirectional Doppler FD-OCT and Microsphere Method.
abstract: OBJECTIVE
  We validated noninvasive Doppler-optical coherence tomography (OCT) blood flow measurements against the terminal microsphere method in a surgical induced optic nerve transection nonhuman primate model.
  
  
  METHODS
  In 6 nonhuman primates, total retinal blood flow (TRBF) was measured with a custom-built dual-beam bidirectional Doppler Fourier Domain (FD)-OCT. Peripapillary retinal nerve fiber layer thickness (RNFLT) was measured by Spectralis spectral-domain (SD)-OCT. Measurements were performed every 10 to 15 days before and after unilateral optic nerve transection (ONT) until RNFLT was reduced by more than 40% from baseline. Before the animals were killed, TRBF was measured using the microsphere technique.
  
  
  RESULTS
  A significant correlation between all arterial and venous Doppler OCT TRBF measurements was found in ONT and contralateral control eyes (both P < 0.01, n = 6). The Bland-Altman analysis showed a bias of 0.57 in the ONT group and 0.02 in the contralateral control group. Also, excellent agreement was observed between Doppler OCT and microsphere measurements (P < 0.01, r = 0.976, bias = 0.54). After ONT, TRBF and RNFLT decreased by -51% ± 42% and -44% ± 2% (n = 5), respectively. In the contralateral control eyes, TRBF and RNFLT were unchanged.
  
  
  CONCLUSIONS
  Very good accordance was found between TRBF measurements, obtained with dual-beam bidirectional Doppler FD-OCT and the microsphere method. It also was possible to monitor changes over time in TRBF after ONT with Doppler OCT. These findings highlight the accuracy and potential of noninvasive Doppler OCT to provide valuable information for detecting early changes in ocular disease in future.
authors.affiliation: Center for Medical Physics and Biomedical Engineering Medical University of Vienna, Vienna, Austria 2Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Told
authors.affiliation: Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States.
authors.forename: Grant
authors.initials: G
authors.lastname: Cull
authors.affiliation: Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Thompson
authors.affiliation: Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States.
authors.forename: Claude F
authors.initials: CF
authors.lastname: Burgoyne
authors.affiliation: Center for Medical Physics and Biomedical Engineering Medical University of Vienna, Vienna, Austria 3Institute of Applied Physics, Vienna University of Technology, Vienna, Austria.
authors.forename: Gerold C
authors.initials: GC
authors.lastname: Aschinger
authors.affiliation: Center for Medical Physics and Biomedical Engineering Medical University of Vienna, Vienna, Austria 4Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.
authors.forename: Leopold
authors.initials: L
authors.lastname: Schmetterer
authors.affiliation: Center for Medical Physics and Biomedical Engineering Medical University of Vienna, Vienna, Austria.
authors.forename: René M
authors.initials: RM
authors.lastname: Werkmeister
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology*; D004195:Disease Models, Animal; D005583:Fourier Analysis; D008253:Macaca mulatta; D008297:Male; D008863:Microspheres; D009900:Optic Nerve / Q000601:surgery; D020221:Optic Nerve Injuries / Q000473:pathology / Q000503:physiopathology*; D012039:Regional Blood Flow / Q000502:physiology*; D012160:Retina / Q000473:pathology / Q000503:physiopathology*; D012165:Retinal Ganglion Cells / Q000473:pathology; D012171:Retinal Vessels / Q000503:physiopathology*; D041623:Tomography, Optical Coherence / Q000379:methods*