Abstract
The choroidal vascular bed has many interesting features such as relatively wide but flat capillaries, fenestrated capillary walls and an enormous blood flow. The high flow rate results in a high oxygen tension in the tissue and is also of importance in the temperature control of the eye. The capillary wall is permeable to plasma proteins which is probably of great importance for the supply of vitamin A to the pigment epithelium. The permeability to low molecular weight substances is very high which results in a tissue fluid similar to plasma with respect to small molecules. It is not clear whether the choriocapillaris is normally reabsorbing fluid transported into the choroid from the retina and from the anterior chamber or if there is a net filtration from the choriocapillaris. Fluid can pass from the choroid through the suprachoroid into the episcleral tissues via the scleral substance and spaces around the blood vessels and nerves.
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References
Alm, A. & A. Bill. Blood flow and oxygen extraction in the cat uvea at normal and high intraocular pressures. Acta Physiol. Scand., 80: 19–28 (1970).
Alm, A. & A. Bill. The oxygen supply to the retina, II. Effects of high intraocular pressure on uveal and retinal blood flow in cats. A study with labelled microspheres including flow determinations in brain and some other tissues. Acta Physiol. Scand., 84: 306–319 (1972).
Alm, A. & A. Bill. Ocular and optic nerve flow at normal and increased intraocular pressures in monkeys (Macaca irus); a study with radioactively labelled microspheres including flow determinations in brain and some other tissues. Exp. Eye Res., 15: 15–29 (1973).
Alm, A., A. Bill & F.A. Young. The effects of pilocarpine and neostigmine on the blood flow through the anterior uvea in monkeys. A study with radioactively labelled microspheres. Exp. Eye Res., 15: 31–36 (1973).
Alm, A., P. Törnquist & J. Stjernschantz. Radioactively labelled microspheres in regional ocular blood flow determinations. 9th Europ. Conf. Microcirculation, Antwerp 1976. Bibl. anat., No. 16, pp. 24–29 (Karger, Basel 1977).
Bellhorn, R.W. Permeability of blood-ocular barriers of neonatal and adult cat to sodium fluorescein. Invest. Ophtalmol. & Vis. Sci., 19: 870–877 (1980).
Bellhorn, R.W. Permeability of blood-ocular barriers of neonatal and adult cats to fluorescein-labeled dextrans of selected molecular sizes. Invest. Ophthalmol. & Vis. Sci., 21: 282–290 (1981).
Bill, A. Intraocular pressure and blood flow through the uvea. A.M.A. Arch. Ophthal., 67: 336–348 (1962).
Bill, A. The albumin exchange in the rabbit eye. Acta Physiol. Scand., 60: 18–29 (1964).
Bill, A. Capillary permeability to and extra vascular dynamics of myoglobin albumin and gammaglobulin in the uvea. Acta Physiol. Scand., 73: 204–219 (1968).
Bill, A. A method to determine osmotically effective albumin and gammaglobulin concentrations in tissue fluids, its application to the uvea and a note on the effects of capillary ‘leaks’ on tissue fluids dynamics. Acta Physiol. Scand., 73: 511–522 (1968).
Bill, A. Blood circulation and fluid dynamics in the eye. Physiol. Rev., 55: 383–417 (1975).
Bill, A. & C. Geijer. Effects of blood flow on albumin turnover in the choroid of unanaesthetized rabbits. Bibl. Anat., 16: 47–50 (1977) (Proceedings of the 9th Europ Conf Microcirculation, Antwerp, 1976).
Bill, A. & J. Stjernschantz. Cholinergic vasoconstrictor effects on the rabbit eye: Vasomotor effects of pentobarbital anesthesia. Acta Physiol. Scand., 108: 419–424 (1980).
Bill, A., P. Törnqvist & A. Alm. The permeability of the intraocular blood vessels. Trans. Ophthal. Soc. U.K., 100: 332–336 (1980).
Marmor, M.F., A.S. Abdul-Rahim & S.D. Cohen. The effect of metabolic inhibitors on retinal adhesion and subretinal fluid reabsorption. Invest. Ophthalmol. Vis. Sci., 19: 893–903 (1980).
Moseley, H. & R. Strang. Prediction of the effect of the choroidal circulation on the retinal temperature during illumination. Bull. Math. Biophysics., 43: 233–238 (1981).
Parver, L.M., C. Auker & D.O. Carpenter. Choroidal blood flow as a heat dissipating mechanism in the macula. Am. J. Ophthalmol., 89: 641–646 (1980).
Pino, R.M. & E. Essner. Permeability of rat choriocapillaris to hemeproteins. J. Histochem. and Cytochem., 29: 281–290 (1981).
Radius, R.L. & D.R. Anderson. Distribution of albumin in the normal monkey eye as revealed by Evans blue fluorescence microscopy. Invest. Ophthalmol. & Vis. Sci., 19: 238–243 (1980).
Risco, J.M. & W. Nopanitaya. Ocular microcirculation. Scanning electron microscopic study. Investigative Ophthalmol. & Vis. Sci., 19: 5–12 (1980).
Shimizu, K. & K. Ujiie. Structure of ocular vessels. Tokyo: Igakushoin Ltd., (1978).
Shiose, Y. Electron microscopic studies on blood-retinal and blood-aqueous barriers. Japanese J. Ophthalmol., 14: 73–87, 1970.
Törnqvist, P. Capillary permeability in cat choroid studied with the single injection technique. Acta Physiol. Scand., 106: 425–430 (1979).
Törnquist, P. & A. Alm. Retinal and choroidal contribution to retinal metabolism in vivo. A study in pigs. Acta Physiol. Scand., 106: 351–357 (1979).
White, T.J., M.A. Mainster, J.H. Tips & P.W. Wilson. Chorioretinal thermal behavior. Bull. Math. Biophysics, 32: 315–322 (1970).
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Bill, A., Sperber, G. & Ujiie, K. Physiology of the choroidal vascular bed. Int Ophthalmol 6, 101–107 (1983). https://doi.org/10.1007/BF00127638
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DOI: https://doi.org/10.1007/BF00127638