Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy.

The aim of the present study was to investigate regulation of blood flow (BF) in the optic nerve head (ONH) and a peripapillary region (PPR) during an isometric exercise-induced increase in ocular perfusion pressure (OPP) using laser speckle flowgraphy (LSFG) in healthy subjects. For this purpose, a...

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Main Authors: Katarzyna J Witkowska, Ahmed M Bata, Giacomo Calzetti, Nikolaus Luft, Klemens Fondi, Piotr A Wozniak, Doreen Schmidl, Matthias Bolz, Alina Popa-Cherecheanu, René M Werkmeister, Gerhard Garhöfer, Leopold Schmetterer
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-01-01
Series:PLoS ONE
Online Access:https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0184772&type=printable
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author Katarzyna J Witkowska
Ahmed M Bata
Giacomo Calzetti
Nikolaus Luft
Klemens Fondi
Piotr A Wozniak
Doreen Schmidl
Matthias Bolz
Alina Popa-Cherecheanu
René M Werkmeister
Gerhard Garhöfer
Leopold Schmetterer
author_facet Katarzyna J Witkowska
Ahmed M Bata
Giacomo Calzetti
Nikolaus Luft
Klemens Fondi
Piotr A Wozniak
Doreen Schmidl
Matthias Bolz
Alina Popa-Cherecheanu
René M Werkmeister
Gerhard Garhöfer
Leopold Schmetterer
author_sort Katarzyna J Witkowska
collection DOAJ
description The aim of the present study was to investigate regulation of blood flow (BF) in the optic nerve head (ONH) and a peripapillary region (PPR) during an isometric exercise-induced increase in ocular perfusion pressure (OPP) using laser speckle flowgraphy (LSFG) in healthy subjects. For this purpose, a total of 27 subjects was included in this study. Mean blur rate in tissue (MT) was measured in the ONH and in a PPR as well as relative flow volume (RFV) in retinal arteries (ART) and veins (VEIN) using LSFG. All participants performed isometric exercise for 6 minutes during which MT and mean arterial pressure were measured every minute. From these data OPP and pressure/flow curves were calculated. Isometric exercise increased OPP, MTONH and MTPRR. The relative increase in OPP (78.5 ± 19.8%) was more pronounced than the increase in BF parameters (MTONH: 18.1 ± 7.7%, MTPRR: 21.1 ± 8.3%, RFVART: 16.5 ±12.0%, RFVVEIN: 17.7 ± 12.4%) indicating for an autoregulatory response of the vasculature. The pressure/flow curves show that MTONH, MTPRR, RFVART, RFVVEIN started to increase at OPP levels of 51.2 ± 2.0%, 58.1 ± 2.4%, 45.6 ± 1.9% and 45.6 ± 1.9% above baseline. These data indicate that ONHBF starts to increase at levels of approx. 50% increase in OPP: This is slightly lower than the values we previously reported from LDF data. Signals from the PPR may have input from both, the retina and the choroid, but the relative contribution is unknown. In addition, retinal BF appears to increase at slightly lower OPP values of approximately 45%. LSFG may be used to study ONH autoregulation in diseases such as glaucoma.<h4>Trial registration</h4>ClinicalTrials.gov NCT02102880.
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spelling doaj.art-f600b96e8d5e4bcd8c9dbe4bfe98a7272025-02-27T05:36:10ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-01129e018477210.1371/journal.pone.0184772Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy.Katarzyna J WitkowskaAhmed M BataGiacomo CalzettiNikolaus LuftKlemens FondiPiotr A WozniakDoreen SchmidlMatthias BolzAlina Popa-CherecheanuRené M WerkmeisterGerhard GarhöferLeopold SchmettererThe aim of the present study was to investigate regulation of blood flow (BF) in the optic nerve head (ONH) and a peripapillary region (PPR) during an isometric exercise-induced increase in ocular perfusion pressure (OPP) using laser speckle flowgraphy (LSFG) in healthy subjects. For this purpose, a total of 27 subjects was included in this study. Mean blur rate in tissue (MT) was measured in the ONH and in a PPR as well as relative flow volume (RFV) in retinal arteries (ART) and veins (VEIN) using LSFG. All participants performed isometric exercise for 6 minutes during which MT and mean arterial pressure were measured every minute. From these data OPP and pressure/flow curves were calculated. Isometric exercise increased OPP, MTONH and MTPRR. The relative increase in OPP (78.5 ± 19.8%) was more pronounced than the increase in BF parameters (MTONH: 18.1 ± 7.7%, MTPRR: 21.1 ± 8.3%, RFVART: 16.5 ±12.0%, RFVVEIN: 17.7 ± 12.4%) indicating for an autoregulatory response of the vasculature. The pressure/flow curves show that MTONH, MTPRR, RFVART, RFVVEIN started to increase at OPP levels of 51.2 ± 2.0%, 58.1 ± 2.4%, 45.6 ± 1.9% and 45.6 ± 1.9% above baseline. These data indicate that ONHBF starts to increase at levels of approx. 50% increase in OPP: This is slightly lower than the values we previously reported from LDF data. Signals from the PPR may have input from both, the retina and the choroid, but the relative contribution is unknown. In addition, retinal BF appears to increase at slightly lower OPP values of approximately 45%. LSFG may be used to study ONH autoregulation in diseases such as glaucoma.<h4>Trial registration</h4>ClinicalTrials.gov NCT02102880.https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0184772&type=printable
spellingShingle Katarzyna J Witkowska
Ahmed M Bata
Giacomo Calzetti
Nikolaus Luft
Klemens Fondi
Piotr A Wozniak
Doreen Schmidl
Matthias Bolz
Alina Popa-Cherecheanu
René M Werkmeister
Gerhard Garhöfer
Leopold Schmetterer
Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy.
PLoS ONE
title Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy.
title_full Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy.
title_fullStr Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy.
title_full_unstemmed Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy.
title_short Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy.
title_sort optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy
url https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0184772&type=printable
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