Choroidal blood flow autoregulation

J. W. Kiel

Research output: Contribution to journalArticle

Abstract

One of the current controversies in eye blood flow research is the issue of choroidal autoregulation. Early studies generally found passive choroidal blood flow responses to changes in perfusion pressure which led to the conclusion that the choroid is devoid of autoregulatory ability. Moreover, the choroid's high flow rate and low oxygen extraction suggested little need for choroidal autoregulation. However, more recent studies find that choroidal blood flow does not always respond passively to changes in perfusion pressure, and that choroidal blood flow can be remarkably well maintained over a wide range of perfusion pressure, particularly when arterial pressure is the manipulated variable. Interestingly, when choroidal blood flow is maintained, the IOP is also largely unresponsive to changes in arterial pressure, but when the choroid is passive, the IOP becomes arterial pressuredependent. This finding suggests IOP homeostasis and perhaps preservation of choroidal thickness and thus retinal position and optical pathlength as a basis for choroidal autoregulation. Thus, there are experimental data and functional arguments to refute or support choroidal autoregulation. Resolving this controversy requires reconciling the discrepancies in the choroidal blood flow studies (i.e., can the results be explained by the blood flow measuring methodologies used or the experimental conditions), and addressing the broader issues of the choroid's functions and the integration of its intrinsic and extrinsic control mechanisms.

Original languageEnglish (US)
JournalInvestigative Ophthalmology and Visual Science
Volume38
Issue number4
StatePublished - 1997

Fingerprint

Homeostasis
Choroid
Perfusion
Arterial Pressure
Pressure
Oxygen
Blood Pressure
Research

ASJC Scopus subject areas

  • Ophthalmology

Cite this

Choroidal blood flow autoregulation. / Kiel, J. W.

In: Investigative Ophthalmology and Visual Science, Vol. 38, No. 4, 1997.

Research output: Contribution to journalArticle

@article{b7124a0bc57840698806890c88a1454d,
title = "Choroidal blood flow autoregulation",
abstract = "One of the current controversies in eye blood flow research is the issue of choroidal autoregulation. Early studies generally found passive choroidal blood flow responses to changes in perfusion pressure which led to the conclusion that the choroid is devoid of autoregulatory ability. Moreover, the choroid's high flow rate and low oxygen extraction suggested little need for choroidal autoregulation. However, more recent studies find that choroidal blood flow does not always respond passively to changes in perfusion pressure, and that choroidal blood flow can be remarkably well maintained over a wide range of perfusion pressure, particularly when arterial pressure is the manipulated variable. Interestingly, when choroidal blood flow is maintained, the IOP is also largely unresponsive to changes in arterial pressure, but when the choroid is passive, the IOP becomes arterial pressuredependent. This finding suggests IOP homeostasis and perhaps preservation of choroidal thickness and thus retinal position and optical pathlength as a basis for choroidal autoregulation. Thus, there are experimental data and functional arguments to refute or support choroidal autoregulation. Resolving this controversy requires reconciling the discrepancies in the choroidal blood flow studies (i.e., can the results be explained by the blood flow measuring methodologies used or the experimental conditions), and addressing the broader issues of the choroid's functions and the integration of its intrinsic and extrinsic control mechanisms.",
author = "Kiel, {J. W.}",
year = "1997",
language = "English (US)",
volume = "38",
journal = "Investigative Ophthalmology and Visual Science",
issn = "0146-0404",
publisher = "Association for Research in Vision and Ophthalmology Inc.",
number = "4",

}

TY - JOUR

T1 - Choroidal blood flow autoregulation

AU - Kiel, J. W.

PY - 1997

Y1 - 1997

N2 - One of the current controversies in eye blood flow research is the issue of choroidal autoregulation. Early studies generally found passive choroidal blood flow responses to changes in perfusion pressure which led to the conclusion that the choroid is devoid of autoregulatory ability. Moreover, the choroid's high flow rate and low oxygen extraction suggested little need for choroidal autoregulation. However, more recent studies find that choroidal blood flow does not always respond passively to changes in perfusion pressure, and that choroidal blood flow can be remarkably well maintained over a wide range of perfusion pressure, particularly when arterial pressure is the manipulated variable. Interestingly, when choroidal blood flow is maintained, the IOP is also largely unresponsive to changes in arterial pressure, but when the choroid is passive, the IOP becomes arterial pressuredependent. This finding suggests IOP homeostasis and perhaps preservation of choroidal thickness and thus retinal position and optical pathlength as a basis for choroidal autoregulation. Thus, there are experimental data and functional arguments to refute or support choroidal autoregulation. Resolving this controversy requires reconciling the discrepancies in the choroidal blood flow studies (i.e., can the results be explained by the blood flow measuring methodologies used or the experimental conditions), and addressing the broader issues of the choroid's functions and the integration of its intrinsic and extrinsic control mechanisms.

AB - One of the current controversies in eye blood flow research is the issue of choroidal autoregulation. Early studies generally found passive choroidal blood flow responses to changes in perfusion pressure which led to the conclusion that the choroid is devoid of autoregulatory ability. Moreover, the choroid's high flow rate and low oxygen extraction suggested little need for choroidal autoregulation. However, more recent studies find that choroidal blood flow does not always respond passively to changes in perfusion pressure, and that choroidal blood flow can be remarkably well maintained over a wide range of perfusion pressure, particularly when arterial pressure is the manipulated variable. Interestingly, when choroidal blood flow is maintained, the IOP is also largely unresponsive to changes in arterial pressure, but when the choroid is passive, the IOP becomes arterial pressuredependent. This finding suggests IOP homeostasis and perhaps preservation of choroidal thickness and thus retinal position and optical pathlength as a basis for choroidal autoregulation. Thus, there are experimental data and functional arguments to refute or support choroidal autoregulation. Resolving this controversy requires reconciling the discrepancies in the choroidal blood flow studies (i.e., can the results be explained by the blood flow measuring methodologies used or the experimental conditions), and addressing the broader issues of the choroid's functions and the integration of its intrinsic and extrinsic control mechanisms.

UR - http://www.scopus.com/inward/record.url?scp=33749098260&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33749098260&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:33749098260

VL - 38

JO - Investigative Ophthalmology and Visual Science

JF - Investigative Ophthalmology and Visual Science

SN - 0146-0404

IS - 4

ER -