title: Optic Disc Perfusion in Primary Open Angle and Normal Tension Glaucoma Eyes Using Optical Coherence Tomography-Based Microangiography.
abstract: To investigate optic disc perfusion differences in normal, primary open-angle glaucoma (POAG), and normal tension glaucoma (NTG) eyes using optical microangiography (OMAG) based optical coherence tomography (OCT) angiography technique.
  
  
  
  Cross-sectional, observational study.
  
  
  
  Twenty-eight normal, 30 POAG, and 31 NTG subjects.
  
  
  
  One eye from each subject was scanned with a 68 kHz Cirrus HD-OCT 5,000-based OMAG prototype system centered at the optic nerve head (ONH) (Carl Zeiss Meditec Inc, Dublin, CA). Microvascular images were generated from the OMAG dataset by detecting the differences in OCT signal between consecutive B-scans. The pre-laminar layer (preLC) was isolated by a semi-automatic segmentation program.
  
  
  
  Optic disc perfusion, quantified as flux, vessel area density, and normalized flux (flux normalized by the vessel area) within the ONH.
  
  
  
  Glaucomatous eyes had significantly lower optic disc perfusion in preLC in all three perfusion metrics (p<0.0001) compared to normal eyes. The visual field (VF) mean deviation (MD) and pattern standard deviation (PSD) were similar between the POAG and NTG groups, and no differences in optic disc perfusion were observed between POAG and NTG. Univariate analysis revealed significant correlation between optic disc perfusion and VF MD, VF PSD, and rim area in both POAG and NTG groups (p≤0.0288). However, normalized optic disc perfusion was correlated with some structural measures (retinal nerve fiber layer thickness and ONH cup/disc ratio) only in POAG eyes.
  
  
  
  Optic disc perfusion detected with OMAG was significantly reduced in POAG and NTG groups compared to normal controls, but no difference was seen between POAG and NTG groups with similar levels of VF damage. Disc perfusion was significantly correlated with VF MD, VF PSD, and rim area in glaucomatous eyes. Vascular changes at the optic disc as measured using OMAG may provide useful information for diagnosis and monitoring of glaucoma.
authors.affiliation: Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America.
authors.forename: Karine D
authors.initials: KD
authors.lastname: Bojikian
authors.affiliation: Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America.|Department of Bioengineering, University of Washington, Seattle, Washington, United States of America.
authors.forename: Chieh-Li
authors.initials: CL
authors.lastname: Chen
authors.affiliation: Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America.
authors.forename: Joanne C
authors.initials: JC
authors.lastname: Wen
authors.affiliation: Department of Bioengineering, University of Washington, Seattle, Washington, United States of America.
authors.forename: Qinqin
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Bioengineering, University of Washington, Seattle, Washington, United States of America.|Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Xin
authors.affiliation: Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America.
authors.forename: Divakar
authors.initials: D
authors.lastname: Gupta
authors.affiliation: Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America.
authors.forename: Raghu C
authors.initials: RC
authors.lastname: Mudumbai
authors.affiliation: Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America.
authors.forename: Murray A
authors.initials: MA
authors.lastname: Johnstone
authors.affiliation: Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America.|Department of Bioengineering, University of Washington, Seattle, Washington, United States of America.
authors.forename: Ruikang K
authors.initials: RK
authors.lastname: Wang
authors.affiliation: Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America.
authors.forename: Philip P
authors.initials: PP
authors.lastname: Chen
mesh_terms: D000792:Angiography / Q000379:methods*; D016022:Case-Control Studies; D005902:Glaucoma, Open-Angle / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D057066:Low Tension Glaucoma / Q000000981:diagnostic imaging / Q000503:physiopathology*; D009898:Optic Disk / Q000098:blood supply*; D041623:Tomography, Optical Coherence / Q000379:methods*