PURPOSE: The aim of this study was to compare the diameter response of retinal arteries and veins after provocation with flickering light regarding the amplitude and temporal course. METHODS: The study included 26 healthy volunteers. The vessel diameter was automatically and continuously measured by the retinal vessel analyzer. The examination consisted of a baseline measurement (100 s) followed by five periods of 20-s flicker light provocation and 80-s follow-up observation. RESULTS: A diameter dilation was observed immediately after the end of the flicker period in arteries (6.9+/-2.8%) and veins (6.5+/-2.8%, difference n.s.). The quotient of arterial and venous dilation (AVDQ) was 1.25+/-0.69 (range: 0.2-2.8). A significant correlation of age and arterial or venous dilation or the AVDQ was not observed. The arterial diameter reduced faster than the venous and reached a minimum of -2.7+/-1.4% at 25.9+/-10.8 s after the end of the flicker phase. The veins were dilated by 0.5+/-1.3% at the time of the maximal individual arterial constriction (p<0.0001). CONCLUSIONS: Flicker-evoked response of retinal arteries and veins did not differ in the dilative amplitude but in the temporal course of the abatement of the dilation.
PURPOSE: The aim of this study was to compare the diameter response of retinal arteries and veins after provocation with flickering light regarding the amplitude and temporal course. METHODS: The study included 26 healthy volunteers. The vessel diameter was automatically and continuously measured by the retinal vessel analyzer. The examination consisted of a baseline measurement (100 s) followed by five periods of 20-s flicker light provocation and 80-s follow-up observation. RESULTS: A diameter dilation was observed immediately after the end of the flicker period in arteries (6.9+/-2.8%) and veins (6.5+/-2.8%, difference n.s.). The quotient of arterial and venous dilation (AVDQ) was 1.25+/-0.69 (range: 0.2-2.8). A significant correlation of age and arterial or venous dilation or the AVDQ was not observed. The arterial diameter reduced faster than the venous and reached a minimum of -2.7+/-1.4% at 25.9+/-10.8 s after the end of the flicker phase. The veins were dilated by 0.5+/-1.3% at the time of the maximal individual arterial constriction (p<0.0001). CONCLUSIONS: Flicker-evoked response of retinal arteries and veins did not differ in the dilative amplitude but in the temporal course of the abatement of the dilation.
Authors: K Polak; G Dorner; B Kiss; E Polska; O Findl; G Rainer; H G Eichler; L Schmetterer Journal: Br J Ophthalmol Date: 2000-11 Impact factor: 4.638
Authors: Katharina Wolf-Maier; Richard S Cooper; José R Banegas; Simona Giampaoli; Hans-Werner Hense; Michel Joffres; Mika Kastarinen; Neil Poulter; Paola Primatesta; Fernando Rodríguez-Artalejo; Birgitta Stegmayr; Michael Thamm; Jaakko Tuomilehto; Diego Vanuzzo; Fenicia Vescio Journal: JAMA Date: 2003-05-14 Impact factor: 56.272
Authors: Harry Leung; Jie Jin Wang; Elena Rochtchina; Ava G Tan; Tien Y Wong; Ronald Klein; Larry D Hubbard; Paul Mitchell Journal: Invest Ophthalmol Vis Sci Date: 2003-07 Impact factor: 4.799