title: Retrobulbar blood flow and ophthalmic perfusion in maximum dynamic exercise.
abstract: OBJECTIVE
  To study the effects of maximum dynamic physical exercise on retrobulbar blood flow and ocular perfusion pressure (OPP).
  
  
  METHODS
  Thirty male subjects undergoing routine periodic medical evaluation were included. All participants underwent cardiac stress test according to a standard protocol. Before the test, the intraocular pressure was measured and colour Doppler imaging was performed with a 7.5 MHz linear probe, to record peak systolic velocity (PSV), end diastolic velocity and resistivity index at the ophthalmic artery (OA), central retinal artery (CRA) and nasal and temporal branches of short posterior ciliary arteries (SPCA). The same measurements were repeated 1 and 30 min after the test.
  
  
  RESULTS
  OPP and PSV at the OA were significantly higher at the 1-min interval, compared with the pretest scores (P = 0.01, in both cases), whereas the respective differences on the 30-min interval were statistically not significant. On the contrary, PSV at the CRA and SPCA were not significantly changed on the same intervals. Differences between pretest and post-test scores for end diastolic velocity and resistivity index were statistically not significant for all examined vessels.
  
  
  CONCLUSIONS
  Maximal physical exercise increases OPP and blood flow at the OA without affecting blood flow at the CRA and SPCA, implying that auto-regulative mechanisms are active in both retinal and choroidal circulations.
authors.affiliation: Department of Ophthalmology, University Hospital of Alexandroupolis, Alexandroupolis, Greece.
authors.forename: Vassilios P
authors.initials: VP
authors.lastname: Kozobolis
authors.forename: Efstathios T
authors.initials: ET
authors.lastname: Detorakis
authors.forename: Anastasios G
authors.initials: AG
authors.lastname: Konstas
authors.forename: Athanassios K
authors.initials: AK
authors.lastname: Achtaropoulos
authors.forename: Evangelos D
authors.initials: ED
authors.lastname: Diamandides
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology*; D019842:Ciliary Arteries / Q000000981:diagnostic imaging / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009880:Ophthalmic Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D011446:Prospective Studies; D012016:Reference Values; D012161:Retinal Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D018615:Ultrasonography, Doppler, Color