| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 From the Institute of Ophthalmology, Catholic University of S. Cuore, Rome, Italy; the 2 Institute of Research in Ophthalmology, Sion, Switzerland; and the 3 University of Lausanne, Lausanne, Switzerland.
PURPOSE. Visual flicker induces a response in human optic nerve blood flow (Fonh) and inner retinal activity, as assessed by laser Doppler flowmetry and electroretinogram (ERG), respectively. In this study the relationship was examined between the flicker-evoked changes in Fonh (RFonh) and ERG when various parameters of the stimulus were varied.
METHODS. In five normal observers (mean age, 41; range, 25–62 years) Fonh and ERG were recorded simultaneously in response to pure red (R) or pure green (G) flicker, as well as heterochromatic R-G flicker (30° field at the posterior pole). RFonh and the changes in the first (1F) and second (2F) harmonic amplitudes of the ERG were documented as a function of the frequency of pure luminance and equiluminant R-G flicker, the mean illuminance of 10-Hz luminance flicker, and the color ratio r = R/(R + G) of a 15-Hz heterochromatic R-G flicker.
RESULTS. Frequency-dependent changes in RFonh were similar to those in both 1F and 2F amplitudes for equiluminant R-G flicker. RFonh and 2F amplitude increased and then saturated with increasing mean illuminance of luminance flicker. They both decreased similarly as the R-G flicker approached the r value corresponding to equiluminance. RFonh was positively correlated with both 1F and 2F amplitudes (r = 0.55 and 0.31, respectively, P < 0.05) when these quantities were recorded as a function of frequency of R-G equiluminant flicker. RFonh was positively correlated with 2F amplitudes when both quantities were recorded as a function of mean illuminance of luminance flicker and r of heterochromatic R-G flicker (r = 0.52 and 0.48, respectively, P 
0.01).
CONCLUSIONS. Under specific experimental conditions, changes in human RFonh are similar to and correlated with those of the flicker ERG 1F and 2F amplitudes. These findings support a relationship between vaso- and neural activity changes in the neural tissue of the human eye.
This article has been cited by other articles:
|
|
 |
|
  K. Inomata, K. Tsunoda, G. Hanazono, Y. Kazato, K. Shinoda, M. Yuzawa, M. Tanifuji, and Y. Miyake Distribution of Retinal Responses Evoked by Transscleral Electrical Stimulation Detected by Intrinsic Signal Imaging in Macaque Monkeys Invest. Ophthalmol. Vis. Sci., May 1, 2008; 49(5): 2193 - 2200. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Feigl, I. B. Stewart, B. Brown, and A. J. Zele Local Neuroretinal Function during Acute Hypoxia in Healthy Older People Invest. Ophthalmol. Vis. Sci., February 1, 2008; 49(2): 807 - 813. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Shakoor, N. P. Blair, M. Mori, and M. Shahidi Chorioretinal Vascular Oxygen Tension Changes in Response to Light Flicker Invest. Ophthalmol. Vis. Sci., November 1, 2006; 47(11): 4962 - 4965. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. D. Abramoff, Y. H. Kwon, D. Ts'o, P. Soliz, B. Zimmerman, J. Pokorny, and R. Kardon Visual Stimulus-Induced Changes in Human Near-Infrared Fundus Reflectance Invest. Ophthalmol. Vis. Sci., February 1, 2006; 47(2): 715 - 721. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. V. Lovasik, H. Kergoat, and M. A. Wajszilber Blue flicker modifies the subfoveal choroidal blood flow in the human eye Am J Physiol Heart Circ Physiol, August 1, 2005; 289(2): H683 - H691. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Porciatti, N. Sorokac, and W. Buchser Habituation of Retinal Ganglion Cell Activity in Response to Steady State Pattern Visual Stimuli in Normal Subjects Invest. Ophthalmol. Vis. Sci., April 1, 2005; 46(4): 1296 - 1302. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. E. Riva, T. Salgarello, E. Logean, A. Colotto, E. M. Galan, and B. Falsini Flicker-Evoked Response Measured at the Optic Disc Rim Is Reduced in Ocular Hypertension and Early Glaucoma Invest. Ophthalmol. Vis. Sci., October 1, 2004; 45(10): 3662 - 3668. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G Garhofer, C Zawinka, H Resch, P Kothy, L Schmetterer, and G T Dorner Reduced response of retinal vessel diameters to flicker stimulation in patients with diabetes Br. J. Ophthalmol., July 1, 2004; 88(7): 887 - 891. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Nagel, W. Vilser, and I. Lanzl Age, Blood Pressure, and Vessel Diameter as Factors Influencing the Arterial Retinal Flicker Response Invest. Ophthalmol. Vis. Sci., May 1, 2004; 45(5): 1486 - 1492. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E Nagel and W Vilser Flicker observation light induces diameter response in retinal arterioles: a clinical methodological study Br. J. Ophthalmol., January 1, 2004; 88(1): 54 - 56. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Polak, B. Wimpissinger, F. Berisha, M. Georgopoulos, and L. Schmetterer Effects of Sildenafil on Retinal Blood Flow and Flicker-Induced Retinal Vasodilatation in Healthy Subjects Invest. Ophthalmol. Vis. Sci., November 1, 2003; 44(11): 4872 - 4876. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K.-H. Huemer, G. Garhofer, C. Zawinka, E. Golestani, B. Litschauer, L. Schmetterer, and G. T. Dorner Effects of dopamine on human retinal vessel diameter and its modulation during flicker stimulation Am J Physiol Heart Circ Physiol, January 1, 2003; 284(1): H358 - H363. [Abstract] [Full Text] [PDF]
|
|
Read all eLetters
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
