Abstract
Purpose We have shown in the companion paper that, under baseline conditions, there is a high degree of association between laser interferometrically measured fundus pulsation amplitude (FPA) and pneumotonometrically measured pulse amplitude (PA) and pulsatile ocular blood flow (POBF). The present study investigated the effect of high pCO2, of high pO2 and of isoproterenol on POBF as assessed with laser interferometry and pneumotonometry.
Methods Pneumotonometry and laser interferometry were performed in young healthy subjects during breathing of 100% O2 (n = 10; hyperoxia) and of 5% CO2 + 95% air (n = 8; hypercapnia). In addition these parameters were studied during stepwise increasing doses of isoproterenol, a β-receptor agonist (n = 8).
Results Inhalation of 5% CO2 + 95% air increased FPA (24 ± 12%, p < 0.001), PA (26 ± 13%, p < 0.001) and POBF (15 ± 8%, p = 0.002). Inhalation of 100% O2 decreased FPA (-5 ± 7%, p = 0.027), but did not change PA or POBF. The effect of 100% O2 inhalation on FPA in the optic disc was more pronounced (-11% to -20%) than in the macula. Isoproterenol caused a dose-dependent increase in FPA, PA and POBF (p < 0.001). The association between the induced changes in FPA and PA or POBF was highly significant.
Conclusions The present study shows that FPA can be taken as a valid relative measure of pulsatile choroidal blood flow. Our results in the optic disc indicate that FPA at the neuroretinal rim and at the cup is influenced by retinal and choroidal circulation.
Similar content being viewed by others
Article PDF
References
Kiel JW . Choroidal myogenic autoregulation and intraocular pressure. Exp Eye Res 1994;58:529–44.
Schmetterer L, Lexer F, Unfried C, Sattmann H, Fercher AF . Topical measurement of fundus pulsations. Opt Eng 1995;34:711–6.
Schmetterer L, Wolzt M, Salomon A, Rheinberger A, Unfried C, Zanaschka G, et al. The effect of isoproterenol, phenylephrine and sodium nitroprusside on fundus pulsations in healthy volunteers. Br J Ophthalmol 1996;80:217–23.
L, Wolzt M, Lexer F, Alschinger C, Gouya G, Zanaschka G, et al. The effect of hyperoxia and hypercapnia on fundus pulsations in the macular and the optic disc region. Exp Eye Res 1995;61:685–90.
Schmetterer L, Lexer F, Graselli U, Findl O, Eichler HG, Wolzt M . The effect of different mixtures of O2 and CO2 on ocular fundus pulsations. Exp Eye Res 1996;63:351–5.
Schmetterer L, Dallinger S, Findl O, Strenn K, Lexer F, Eichler HG, et al. A comparison between laser interferometric measurement of fundus pulsation and pneumotonometric measurement of pulsatile ocular blood flow. 1. Baseline considerations. Eye 2000;14:39–45.
Aim A, Bill A . The oxygen supply to the retina. II. Effects of high intraocular pressure and of increased arterial carbon dioxide tension in uveal and retinal blood flow in cats. Acta Physiol Scand 1972;84:306–19.
Tsacopoulos M, David NJ . The effect of arterial pC02 on relative retinal blood flow in monkeys. Invest Ophthalmol 1973;12:335–47.
Harris A, Arend 0, Wolf S, Cantor LB, Martin B . CO2 dependence of retinal arterial and capillary blood velocity. Acta Ophthalmol 1995;73:421–4.
Friedman E, Chandra SR . Choroidal blood flow. III. Effects of oxygen and carbon dioxide. Arch Ophthalmol 1972;87:70–1.
Riva CE, Cranstoun SD, Grunwald JE, Petrig BL . Choroidal blood flow in the foveal region of the human ocular fundus. Invest Ophthalmol Vis Sci 1994;35:4273–81.
Riva CE, Petrig BL . Choroidal blood flow by laser Doppler flowmetry. Opt Eng 1995;34:746–52.
Riva CE, Grunwald JE, Sinclair SH . Laser Doppler velocimetry study of the effect of pure oxygen breathing on retinal blood flow. Invest Ophthalmol Vis Sci 1983;24:47–51.
Grunwald JE, Riva CE, Petrig BL, Sinclair SH, Brucker AJ . Effect of pure O2-breathing on retinal blood flow in normals and in patients with background diabetic retinopathy. Curr Eye Res 1984;3:239–41.
Langhans M, Michelson G, Groh MJM . Effects of breathing 100% oxygen on retinal and optic nerve head capillary blood flow in smokers and non-smokers. Br J Ophthalmol 1997;81:355–9.
Strenn K, Menapace R, Rainer G, Findl O, Wolzt M, Schmetterer L . Reproducibility and sensitivity of scanning laser Doppler flowmetry during graded changes in pO2 . Br J Ophthalmol 1997;81:360–4.
Butt Z, O'Brien C . Reproducibility of pulsatile ocular blood flow measurements. J Glaucoma 1995;4:214–8.
Schmetterer L, Dallinger S, Findl O, Strenn K, Graselli U, Eichler HG, et al. Noninvasive investigations of the normal ocular circulation. Invest Ophthalmol Vis Sci 1998;39:1210–20.
Hayreh SS . The optic nerve head circulation in health and disease. Exp Eye Res 1995;61:259–72.
Riva CE, Harino S, Petrig BL, Shonat RD . Laser Doppler flowmetry in the optic nerve. Exp Eye Res 1992;55:499–506.
Schmetterer L, Findl O, Strenn K, Fasching P, Zanaschka G, Eichler HG, et al. Ocular and systemic reactivity to isoprenaline in patients with insulin-dependent diabetes mellitus. Eur J Clin Invest 1997;27:750–4.
Bruninink A, Dawis S, Niemeyer G, Lichtensteiger W . Catecholaminergic binding sites in cat retina, pigment epithelium and choroid. Exp Eye Res 1986;43:147–51.
Grajewski A, Ferrari-Dileo G, Feuer W, Anderson D . Beta adrenergic responsiveness of choroidal vasculature. Ophthalmology 1991;98:989–95.
Krejcy K, Wolzt M, Kreuzer C, Breiteneder H, Schùtz W, Eichler HG, et al. Characterisation of angiotensin II effects on cerebral and ocular circulation by noninvasive methods. Br J Clin Pharmacol 1997;43:501–8.
Matulla B, Streit G, Pieh S, Findl O, Entlicher J, Graselli U, et al. Effects of losartan on cerebral and ocular circulation in healthy subjects. Br J Clin Pharmacol 1997;44:369–75.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Schmetterer, L., Dallinger, S., Findl, O. et al. A comparison between laser interferometric measurement of fundus pulsation and pneumotonometric measurement of pulsatile ocular blood flow 2. Effects of changes in pCO2 and pO2 and of isoproterenol. Eye 14, 46–52 (2000). https://doi.org/10.1038/eye.2000.10
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/eye.2000.10