Avtor/Urednik		Zaletel, Marjan; Žvan, Bojana; Štrucl, Martin; Pogačnik, Tomaž; Kiauta, Tomaž
Naslov		The influence of brightness, colour and complexity on visual evoked Doppler flow responses
Tip		članek
Vir		Ultrasound Med Biol
Vol. in št.		Letnik 28, št. 7
Leto izdaje		2002
Obseg		str. 917-22
Jezik		eng
Abstrakt		The purpose of this study was to evaluate specific influence of colour, brightness and complexity on visual evoked flow responses (VEFRs). A total of 31 healthy subjects aged 35.1 +/- 7.7 years participated in the study. Mean arterial velocity was measured in the right posterior cerebral artery (v(pca)) and in the left middle cerebral artery (v(mca)) by Multi-DopX4 (DWL). Simple-white (SW), red (R) and complex-checkerboard (C) stimuli were used. VEFRs were determined by the difference of the v(pca):v(mca) ratio before and after stimulation. The VEFRs of SW with brightness of 21.4 cd/m(2), 10.5 cd/m(2) and 2 cd/m(2) were 8.7 +/- 3.4%, 9.1 +/- 3.0% and 8.0 +/- 3.7%, respectively (p < 0.001). The VEFRs of R and C stimuli were 10.4 +/- 6.5% and 12.4 +/- 6.1%, respectively (p < 0.001). ANOVA for repeated measurements did not show significant variances (p = 0.295) between VEFRs of SW of different brightness, but variances between VEFRs of SW, R and C stimuli were significant (p < 0.001). We found significant differences between VEFRs of SW and of C stimuli (3.8 +/- 1.9%, p < 0.001), VEFRs of SW and of R stimuli (1.8 +/- 2.4%, p = 0.008) as well as between VEFRs of C and of R stimuli (2.0 +/- 2.5%, p = 0.010). We have concluded that SW, R and C stimuli have a specific influence on VEFRs. Brightness does not appear to affect VEFRs
Deskriptorji		CEREBRAL ARTERIES BLOOD FLOW VELOCITY ULTRASONOGRAPHY, DOPPLER, COLOR ADULT