title: Rigidity of retinal vessel in untreated eyes of normal tension primary open-angle glaucoma patients.
abstract: BACKGROUND
  To analyze pulse wave propagation in the ocular circulation and vessel stiffness in untreated eyes of normal tension primary open-angle glaucoma (NTG) patients.
  
  
  METHODS
  Inferotemporal retinal vessels of 22 NTG eyes and 25 controls were examined with a Retinal Vessel Analyzer. Inferotemporal peripapillary retinal nerve fiber layer thickness was measured by ocular coherence tomography. Phase delay between venous trough and arterial peak was assessed at 3 sites centrifugal from the disc and a choroid-to-retina pulse delay was calculated as an estimation of vessel rigidity.
  
  
  RESULTS
  There was choroid-to-retina pulse delay of 0.26±0.08, 0.30±0.11, and 0.33±0.11 seconds, respectively, in NTG eyes at proximal, middle, and distal sites; in control eyes, the corresponding values were 0.28±0.10, 0.35±0.12, and 0.40±0.17 seconds. Average choroid-to-retina pulse delay was shorter in NTG eyes (P=0.028). Retinal nerve fiber layer (inferotemporal) showed an opposite correlation with choroid-to-retina pulse delay in controls (r=-0.48, P=0.019) and in NTG eyes (r=0.47, P=0.032 ).
  
  
  CONCLUSIONS
  Untreated NTG eyes show stiffer retinal vessels. Vessel rigidity correlates with level of glaucomatous damage.
authors.affiliation: Department of Ophthalmology, University Hospital Basel, Basel, Switzerland.
authors.forename: Alexander
authors.initials: A
authors.lastname: Oettli
authors.forename: Konstantin
authors.initials: K
authors.lastname: Gugleta
authors.forename: Asan
authors.initials: A
authors.lastname: Kochkorov
authors.forename: Robert
authors.initials: R
authors.lastname: Katamay
authors.forename: Josef
authors.initials: J
authors.lastname: Flammer
authors.forename: Selim
authors.initials: S
authors.lastname: Orgul
mesh_terms: D000328:Adult; D000368:Aged; D001775:Blood Circulation; D001794:Blood Pressure / Q000502:physiology; D003430:Cross-Sectional Studies; D005260:Female; D005583:Fourier Analysis; D005902:Glaucoma, Open-Angle / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology; D012165:Retinal Ganglion Cells / Q000473:pathology; D012171:Retinal Vessels / Q000502:physiology*; D041623:Tomography, Optical Coherence