Theoretical analysis of vascular regulatory mechanisms contributing to retinal blood flow autoregulation

Julia Arciero, Alon Harris, Brent Siesky, Annahita Amireskandari, Victoria Gershuny, Aaron Pickrell, Giovanna Guidoboni

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

Purpose. To study whether impaired retinal autoregulation is a risk factor for glaucoma, the relationship between vascular regulatory mechanisms and glaucoma progression needs to be investigated. In this study, a vascular wall mechanics model is used to predict the relative importance of regulatory mechanisms in achieving retinal autoregulation. Methods. Resistance vessels are assumed to respond to changes in pressure, shear stress, carbon dioxide (CO2), and the downstream metabolic state communicated via conducted responses. Model parameters governing wall tension are fit to pressure and diameter data from porcine retinal arterioles. The autoregulation pressure range for control and elevated levels of IOP is predicted. Results. The factor by which flow changes as the blood pressure exiting the central retinal artery is varied between 28 and 40 mm Hg is used to indicate the degree of autoregulation (1 indicates perfect autoregulation). In the presence of only the myogenic response mechanism, the factor is 2.06. In the presence of the myogenic and CO2 responses, the factor is 1.22. The combination of myogenic, shear, CO2, and metabolic responses yields the best autoregulation (factor of 1.10). Conclusions. Model results are compared with flow and pressure data from multiple patient studies, and the combined effects of the metabolic and CO2 responses are predicted to be critical for achieving retinal autoregulation. When IOP is elevated, the model predicts a decrease in the autoregulation range toward low perfusion pressure, which is consistent with observations that glaucoma is associated with decreased perfusion pressure.

Original languageEnglish
Pages (from-to)5584-5593
Number of pages10
JournalInvestigative Ophthalmology and Visual Science
Volume54
Issue number8
DOIs
StatePublished - 2013

Fingerprint

Blood Vessels
Homeostasis
Pressure
Glaucoma
Perfusion
Retinal Artery
Arterioles
Mechanics
Carbon Dioxide
Swine
Blood Pressure

Keywords

  • Autoregulation
  • Blood flow regulation
  • Glaucoma
  • Metabolic response
  • Myogenic response
  • Retina

ASJC Scopus subject areas

  • Ophthalmology
  • Sensory Systems
  • Cellular and Molecular Neuroscience

Cite this

Theoretical analysis of vascular regulatory mechanisms contributing to retinal blood flow autoregulation. / Arciero, Julia; Harris, Alon; Siesky, Brent; Amireskandari, Annahita; Gershuny, Victoria; Pickrell, Aaron; Guidoboni, Giovanna.

In: Investigative Ophthalmology and Visual Science, Vol. 54, No. 8, 2013, p. 5584-5593.

Research output: Contribution to journalArticle

Arciero, Julia ; Harris, Alon ; Siesky, Brent ; Amireskandari, Annahita ; Gershuny, Victoria ; Pickrell, Aaron ; Guidoboni, Giovanna. / Theoretical analysis of vascular regulatory mechanisms contributing to retinal blood flow autoregulation. In: Investigative Ophthalmology and Visual Science. 2013 ; Vol. 54, No. 8. pp. 5584-5593.
@article{39c1e28b23b5448eba207c2f8784b941,
title = "Theoretical analysis of vascular regulatory mechanisms contributing to retinal blood flow autoregulation",
abstract = "Purpose. To study whether impaired retinal autoregulation is a risk factor for glaucoma, the relationship between vascular regulatory mechanisms and glaucoma progression needs to be investigated. In this study, a vascular wall mechanics model is used to predict the relative importance of regulatory mechanisms in achieving retinal autoregulation. Methods. Resistance vessels are assumed to respond to changes in pressure, shear stress, carbon dioxide (CO2), and the downstream metabolic state communicated via conducted responses. Model parameters governing wall tension are fit to pressure and diameter data from porcine retinal arterioles. The autoregulation pressure range for control and elevated levels of IOP is predicted. Results. The factor by which flow changes as the blood pressure exiting the central retinal artery is varied between 28 and 40 mm Hg is used to indicate the degree of autoregulation (1 indicates perfect autoregulation). In the presence of only the myogenic response mechanism, the factor is 2.06. In the presence of the myogenic and CO2 responses, the factor is 1.22. The combination of myogenic, shear, CO2, and metabolic responses yields the best autoregulation (factor of 1.10). Conclusions. Model results are compared with flow and pressure data from multiple patient studies, and the combined effects of the metabolic and CO2 responses are predicted to be critical for achieving retinal autoregulation. When IOP is elevated, the model predicts a decrease in the autoregulation range toward low perfusion pressure, which is consistent with observations that glaucoma is associated with decreased perfusion pressure.",
keywords = "Autoregulation, Blood flow regulation, Glaucoma, Metabolic response, Myogenic response, Retina",
author = "Julia Arciero and Alon Harris and Brent Siesky and Annahita Amireskandari and Victoria Gershuny and Aaron Pickrell and Giovanna Guidoboni",
year = "2013",
doi = "10.1167/iovs.12-11543",
language = "English",
volume = "54",
pages = "5584--5593",
journal = "Investigative Ophthalmology and Visual Science",
issn = "0146-0404",
publisher = "Association for Research in Vision and Ophthalmology Inc.",
number = "8",

}

TY - JOUR

T1 - Theoretical analysis of vascular regulatory mechanisms contributing to retinal blood flow autoregulation

AU - Arciero, Julia

AU - Harris, Alon

AU - Siesky, Brent

AU - Amireskandari, Annahita

AU - Gershuny, Victoria

AU - Pickrell, Aaron

AU - Guidoboni, Giovanna

PY - 2013

Y1 - 2013

N2 - Purpose. To study whether impaired retinal autoregulation is a risk factor for glaucoma, the relationship between vascular regulatory mechanisms and glaucoma progression needs to be investigated. In this study, a vascular wall mechanics model is used to predict the relative importance of regulatory mechanisms in achieving retinal autoregulation. Methods. Resistance vessels are assumed to respond to changes in pressure, shear stress, carbon dioxide (CO2), and the downstream metabolic state communicated via conducted responses. Model parameters governing wall tension are fit to pressure and diameter data from porcine retinal arterioles. The autoregulation pressure range for control and elevated levels of IOP is predicted. Results. The factor by which flow changes as the blood pressure exiting the central retinal artery is varied between 28 and 40 mm Hg is used to indicate the degree of autoregulation (1 indicates perfect autoregulation). In the presence of only the myogenic response mechanism, the factor is 2.06. In the presence of the myogenic and CO2 responses, the factor is 1.22. The combination of myogenic, shear, CO2, and metabolic responses yields the best autoregulation (factor of 1.10). Conclusions. Model results are compared with flow and pressure data from multiple patient studies, and the combined effects of the metabolic and CO2 responses are predicted to be critical for achieving retinal autoregulation. When IOP is elevated, the model predicts a decrease in the autoregulation range toward low perfusion pressure, which is consistent with observations that glaucoma is associated with decreased perfusion pressure.

AB - Purpose. To study whether impaired retinal autoregulation is a risk factor for glaucoma, the relationship between vascular regulatory mechanisms and glaucoma progression needs to be investigated. In this study, a vascular wall mechanics model is used to predict the relative importance of regulatory mechanisms in achieving retinal autoregulation. Methods. Resistance vessels are assumed to respond to changes in pressure, shear stress, carbon dioxide (CO2), and the downstream metabolic state communicated via conducted responses. Model parameters governing wall tension are fit to pressure and diameter data from porcine retinal arterioles. The autoregulation pressure range for control and elevated levels of IOP is predicted. Results. The factor by which flow changes as the blood pressure exiting the central retinal artery is varied between 28 and 40 mm Hg is used to indicate the degree of autoregulation (1 indicates perfect autoregulation). In the presence of only the myogenic response mechanism, the factor is 2.06. In the presence of the myogenic and CO2 responses, the factor is 1.22. The combination of myogenic, shear, CO2, and metabolic responses yields the best autoregulation (factor of 1.10). Conclusions. Model results are compared with flow and pressure data from multiple patient studies, and the combined effects of the metabolic and CO2 responses are predicted to be critical for achieving retinal autoregulation. When IOP is elevated, the model predicts a decrease in the autoregulation range toward low perfusion pressure, which is consistent with observations that glaucoma is associated with decreased perfusion pressure.

KW - Autoregulation

KW - Blood flow regulation

KW - Glaucoma

KW - Metabolic response

KW - Myogenic response

KW - Retina

UR - http://www.scopus.com/inward/record.url?scp=84882749291&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84882749291&partnerID=8YFLogxK

U2 - 10.1167/iovs.12-11543

DO - 10.1167/iovs.12-11543

M3 - Article

C2 - 23847315

AN - SCOPUS:84882749291

VL - 54

SP - 5584

EP - 5593

JO - Investigative Ophthalmology and Visual Science

JF - Investigative Ophthalmology and Visual Science

SN - 0146-0404

IS - 8

ER -