title: Static characteristics and dynamic functionality of retinal vessels in longer eyes with or without pathologic myopia.
abstract: OBJECTIVE
  To analyze major retinal vessels in eyes with high myopia by means of the Dynamic Vessel Analyzer (DVA) in order to gather insight on retinal vascular functionality and better understand why these eyes are resistant to diabetes-related changes.
  
  
  METHODS
  A total of 20 high-myopia eyes with pathologic myopia, 20 high-myopia eyes without pathologic myopia and 20 age- and sex-matched control subjects (without pathologic myopia) were included and compared.
  
  
  RESULTS
  Dynamic analysis showed mean arterial dilation of 2.44 ± 1.59 % in high-myopia eyes with pathologic myopia, 2.67 ± 1.17 in high-myopia without pathologic myopia eyes, and 3.28 ± 1.46 % in healthy eyes. Mean venous dilation was 3.45 ± 1.82 %, 3.57 ± 1.72, and 4.45 ± 2.72 % respectively. Static analysis in high myopia eyes with pathologic myopia showed a mean central retinal artery equivalent (CRAE) of 171.6 ± 24.3, a mean central retinal vein equivalent (CRVE) of 199.5 ± 27.73, and a mean arteriovenous ratio (AVR) of 0.86 ± 0.01. In patients with high myopia without pathologic myopia, we found a mean CRAE of 173 ± 21.6, a mean CRVE of 198.2 ± 18.8, and a mean AVR of 0.87 ± 0.1. In control subjects, mean CRAE was 190.3 ± 11.93, mean was CRVE 215.7 ± 13.30, and mean AVR was 0.88 ± 0.04.
  
  
  CONCLUSIONS
  Static and dynamic tests revealed that in high-myopia eyes, the vessels at the retinal posterior pole have reduced diameter, but are functionally comparable to control subjects. This supports the hypothesis of reduced oxygen consumption in high-myopia eyes.
authors.affiliation: Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, University Vita-Salute San Raffaele, Via Olgettina 60, Milan, 20132, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: La Spina
authors.affiliation: Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, University Vita-Salute San Raffaele, Via Olgettina 60, Milan, 20132, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Corvi
authors.affiliation: Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, University Vita-Salute San Raffaele, Via Olgettina 60, Milan, 20132, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Bandello
authors.affiliation: Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, University Vita-Salute San Raffaele, Via Olgettina 60, Milan, 20132, Italy. giuseppe.querques@hotmail.it.|Department of Ophthalmology, University Paris Est Creteil, Centre Hospitalier Intercommunal de Creteil, Creteil, France. giuseppe.querques@hotmail.it.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Querques
mesh_terms: D000328:Adult; D058452:Axial Length, Eye / Q000473:pathology; D001794:Blood Pressure / Q000502:physiology; D001824:Body Constitution; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D047728:Myopia, Degenerative / Q000503:physiopathology*; D010101:Oxygen Consumption / Q000502:physiology; D012171:Retinal Vessels / Q000502:physiology*; D014786:Vision Disorders / Q000503:physiopathology; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult
keywords: Axial length; Dynamic vessel analyzer; High myopia; Major retinal vessels; Pathologic myopia