Changes in pupil dynamics at high altitude--an observational study using a handheld pupillometer

Gross pupil dynamics are used as an indirect measure of brain function. Changes in hypoxia and intracranial pressure are thought to alter pupil responses to light. This study assessed a portable handheld pupil measuring device (pupillometer) in the field investigating the changes in pupil size, spee...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:High altitude medicine & biology 2008-12, Vol.9 (4), p.319-325
Hauptverfasser: Wilson, Mark H, Edsell, Mark, Imray, Chris, Wright, Alex
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
container_end_page 325
container_issue 4
container_start_page 319
container_title High altitude medicine & biology
container_volume 9
creator Wilson, Mark H
Edsell, Mark
Imray, Chris
Wright, Alex
description Gross pupil dynamics are used as an indirect measure of brain function. Changes in hypoxia and intracranial pressure are thought to alter pupil responses to light. This study assessed a portable handheld pupil measuring device (pupillometer) in the field investigating the changes in pupil size, speed of reaction, and rate of constriction/dilatation with hypoxia induced by changes in altitude. A correlation between pupil dynamics and acute mountain sickness was sought. Seventeen volunteers were studied following acute exposure to 3450 m and then during a trek to 4770 m in Ladakh, India. The pupillometer was used to record maximum and minimum pupil diameter in response to a standard light source with calculation of latency, constriction and dilatation velocities. Acute mountain sickness (AMS) was recorded using Lake Louise self completed questionnaires both in the morning and afternoon on each day. Acute altitude exposure resulted in a significant reduction of percentage change in pupil size (36.5% to 24.1% p=
doi_str_mv 10.1089/ham.2008.1026
format Article
fullrecord <record><control><sourceid>gale_cross</sourceid><recordid>TN_cdi_gale_infotracmisc_A205747010</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><galeid>A205747010</galeid><sourcerecordid>A205747010</sourcerecordid><originalsourceid>FETCH-LOGICAL-c358t-67e913eb0b2654428eff806d786817d742d81e55f59bf9446e57fda68f52371f3</originalsourceid><addsrcrecordid>eNptkctLxDAQxoMo7rp69CoBz1mTtGnS47L4ggUveq5pM2kjfdG0wv73pnRBBJnDPPjNBzMfQreMbhlV6UOlmy2nVIWOJ2dozYSQRCWKn881l4TyVK7QlfdflNJYReISrVjKmEiZXKPPfaXbEjx2Le6n3tXYHFvduMJjPeLKlRXW9ejGyQAhusVd7mH41qPrWl1jH-ZHPHnXlljjoGQqqM0iVHcNjDBcowuraw83p7xBH0-P7_sXcnh7ft3vDqSIhBpJIiFlEeQ054mIY67AWkUTI8MpTBoZc6MYCGFFmts0jhMQ0hqdKCt4JJmNNuh-0S11DZlrbTcOumicL7Idp0LGkjIaqO0_VAgD4eauBevC_M8CWRaKofN-AJv1g2v0cMwYzWYDsmBANhuQzQYE_m7h-ylvwPzSp49HP9qRgEQ</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype></control><display><type>article</type><title>Changes in pupil dynamics at high altitude--an observational study using a handheld pupillometer</title><source>MEDLINE</source><source>Alma/SFX Local Collection</source><creator>Wilson, Mark H ; Edsell, Mark ; Imray, Chris ; Wright, Alex</creator><creatorcontrib>Wilson, Mark H ; Edsell, Mark ; Imray, Chris ; Wright, Alex ; Birmingham Medical Research Expeditionary Society ; and the Birmingham Medical Research Expeditionary Society</creatorcontrib><description>Gross pupil dynamics are used as an indirect measure of brain function. Changes in hypoxia and intracranial pressure are thought to alter pupil responses to light. This study assessed a portable handheld pupil measuring device (pupillometer) in the field investigating the changes in pupil size, speed of reaction, and rate of constriction/dilatation with hypoxia induced by changes in altitude. A correlation between pupil dynamics and acute mountain sickness was sought. Seventeen volunteers were studied following acute exposure to 3450 m and then during a trek to 4770 m in Ladakh, India. The pupillometer was used to record maximum and minimum pupil diameter in response to a standard light source with calculation of latency, constriction and dilatation velocities. Acute mountain sickness (AMS) was recorded using Lake Louise self completed questionnaires both in the morning and afternoon on each day. Acute altitude exposure resulted in a significant reduction of percentage change in pupil size (36.5% to 24.1% p=&lt;0.001), significant delay in pupillary contraction (latency; 0.208 to 0.223 seconds p=0.015) and a significant slowing of the rate of contraction (constriction velocity; -2.77 mm/s to -1.75 mm/s p=0.012). These changes reverted to normal during a period of acclimatization. A significant diurnal variation in pupil size was also observed. There was no significant difference between subjects with and without AMS. The handheld pupillometer is a suitable robust tool for monitoring changes in pupil dynamics in the field. With acute exposure to hypobaric hypoxia associated with an ascent to a moderate altitude, there is a general slowing of pupil function which reverts to normal within a few days of acclimatization. There appears to be a marked diurnal variation in pupil size. The measurements clearly demonstrated an effect of hypoxia on cerebral function, but these changes did not relate to moderate AMS.</description><identifier>ISSN: 1527-0297</identifier><identifier>EISSN: 1557-8682</identifier><identifier>DOI: 10.1089/ham.2008.1026</identifier><identifier>PMID: 19115917</identifier><language>eng</language><publisher>United States: Mary Ann Liebert, Inc</publisher><subject>Acclimatization - physiology ; Acute Disease ; Adult ; Aged ; Altitude ; Altitude Sickness - physiopathology ; Analysis of Variance ; Brain ; Diagnostic Techniques, Ophthalmological - instrumentation ; Environmental Monitoring - methods ; Female ; Humans ; India ; Male ; Medical examination ; Middle Aged ; Mountain sickness ; Physiological aspects ; Prospective Studies ; Pupil (Eye) ; Pupil - physiology ; Reference Values ; Reflex, Pupillary - physiology ; Risk factors</subject><ispartof>High altitude medicine &amp; biology, 2008-12, Vol.9 (4), p.319-325</ispartof><rights>COPYRIGHT 2008 Mary Ann Liebert, Inc.</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c358t-67e913eb0b2654428eff806d786817d742d81e55f59bf9446e57fda68f52371f3</citedby><cites>FETCH-LOGICAL-c358t-67e913eb0b2654428eff806d786817d742d81e55f59bf9446e57fda68f52371f3</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>314,776,780,27901,27902</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/19115917$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Wilson, Mark H</creatorcontrib><creatorcontrib>Edsell, Mark</creatorcontrib><creatorcontrib>Imray, Chris</creatorcontrib><creatorcontrib>Wright, Alex</creatorcontrib><creatorcontrib>Birmingham Medical Research Expeditionary Society</creatorcontrib><creatorcontrib>and the Birmingham Medical Research Expeditionary Society</creatorcontrib><title>Changes in pupil dynamics at high altitude--an observational study using a handheld pupillometer</title><title>High altitude medicine &amp; biology</title><addtitle>High Alt Med Biol</addtitle><description>Gross pupil dynamics are used as an indirect measure of brain function. Changes in hypoxia and intracranial pressure are thought to alter pupil responses to light. This study assessed a portable handheld pupil measuring device (pupillometer) in the field investigating the changes in pupil size, speed of reaction, and rate of constriction/dilatation with hypoxia induced by changes in altitude. A correlation between pupil dynamics and acute mountain sickness was sought. Seventeen volunteers were studied following acute exposure to 3450 m and then during a trek to 4770 m in Ladakh, India. The pupillometer was used to record maximum and minimum pupil diameter in response to a standard light source with calculation of latency, constriction and dilatation velocities. Acute mountain sickness (AMS) was recorded using Lake Louise self completed questionnaires both in the morning and afternoon on each day. Acute altitude exposure resulted in a significant reduction of percentage change in pupil size (36.5% to 24.1% p=&lt;0.001), significant delay in pupillary contraction (latency; 0.208 to 0.223 seconds p=0.015) and a significant slowing of the rate of contraction (constriction velocity; -2.77 mm/s to -1.75 mm/s p=0.012). These changes reverted to normal during a period of acclimatization. A significant diurnal variation in pupil size was also observed. There was no significant difference between subjects with and without AMS. The handheld pupillometer is a suitable robust tool for monitoring changes in pupil dynamics in the field. With acute exposure to hypobaric hypoxia associated with an ascent to a moderate altitude, there is a general slowing of pupil function which reverts to normal within a few days of acclimatization. There appears to be a marked diurnal variation in pupil size. The measurements clearly demonstrated an effect of hypoxia on cerebral function, but these changes did not relate to moderate AMS.</description><subject>Acclimatization - physiology</subject><subject>Acute Disease</subject><subject>Adult</subject><subject>Aged</subject><subject>Altitude</subject><subject>Altitude Sickness - physiopathology</subject><subject>Analysis of Variance</subject><subject>Brain</subject><subject>Diagnostic Techniques, Ophthalmological - instrumentation</subject><subject>Environmental Monitoring - methods</subject><subject>Female</subject><subject>Humans</subject><subject>India</subject><subject>Male</subject><subject>Medical examination</subject><subject>Middle Aged</subject><subject>Mountain sickness</subject><subject>Physiological aspects</subject><subject>Prospective Studies</subject><subject>Pupil (Eye)</subject><subject>Pupil - physiology</subject><subject>Reference Values</subject><subject>Reflex, Pupillary - physiology</subject><subject>Risk factors</subject><issn>1527-0297</issn><issn>1557-8682</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2008</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNptkctLxDAQxoMo7rp69CoBz1mTtGnS47L4ggUveq5pM2kjfdG0wv73pnRBBJnDPPjNBzMfQreMbhlV6UOlmy2nVIWOJ2dozYSQRCWKn881l4TyVK7QlfdflNJYReISrVjKmEiZXKPPfaXbEjx2Le6n3tXYHFvduMJjPeLKlRXW9ejGyQAhusVd7mH41qPrWl1jH-ZHPHnXlljjoGQqqM0iVHcNjDBcowuraw83p7xBH0-P7_sXcnh7ft3vDqSIhBpJIiFlEeQ054mIY67AWkUTI8MpTBoZc6MYCGFFmts0jhMQ0hqdKCt4JJmNNuh-0S11DZlrbTcOumicL7Idp0LGkjIaqO0_VAgD4eauBevC_M8CWRaKofN-AJv1g2v0cMwYzWYDsmBANhuQzQYE_m7h-ylvwPzSp49HP9qRgEQ</recordid><startdate>20081201</startdate><enddate>20081201</enddate><creator>Wilson, Mark H</creator><creator>Edsell, Mark</creator><creator>Imray, Chris</creator><creator>Wright, Alex</creator><general>Mary Ann Liebert, Inc</general><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope></search><sort><creationdate>20081201</creationdate><title>Changes in pupil dynamics at high altitude--an observational study using a handheld pupillometer</title><author>Wilson, Mark H ; Edsell, Mark ; Imray, Chris ; Wright, Alex</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c358t-67e913eb0b2654428eff806d786817d742d81e55f59bf9446e57fda68f52371f3</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2008</creationdate><topic>Acclimatization - physiology</topic><topic>Acute Disease</topic><topic>Adult</topic><topic>Aged</topic><topic>Altitude</topic><topic>Altitude Sickness - physiopathology</topic><topic>Analysis of Variance</topic><topic>Brain</topic><topic>Diagnostic Techniques, Ophthalmological - instrumentation</topic><topic>Environmental Monitoring - methods</topic><topic>Female</topic><topic>Humans</topic><topic>India</topic><topic>Male</topic><topic>Medical examination</topic><topic>Middle Aged</topic><topic>Mountain sickness</topic><topic>Physiological aspects</topic><topic>Prospective Studies</topic><topic>Pupil (Eye)</topic><topic>Pupil - physiology</topic><topic>Reference Values</topic><topic>Reflex, Pupillary - physiology</topic><topic>Risk factors</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Wilson, Mark H</creatorcontrib><creatorcontrib>Edsell, Mark</creatorcontrib><creatorcontrib>Imray, Chris</creatorcontrib><creatorcontrib>Wright, Alex</creatorcontrib><creatorcontrib>Birmingham Medical Research Expeditionary Society</creatorcontrib><creatorcontrib>and the Birmingham Medical Research Expeditionary Society</creatorcontrib><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><jtitle>High altitude medicine &amp; biology</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Wilson, Mark H</au><au>Edsell, Mark</au><au>Imray, Chris</au><au>Wright, Alex</au><aucorp>Birmingham Medical Research Expeditionary Society</aucorp><aucorp>and the Birmingham Medical Research Expeditionary Society</aucorp><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Changes in pupil dynamics at high altitude--an observational study using a handheld pupillometer</atitle><jtitle>High altitude medicine &amp; biology</jtitle><addtitle>High Alt Med Biol</addtitle><date>2008-12-01</date><risdate>2008</risdate><volume>9</volume><issue>4</issue><spage>319</spage><epage>325</epage><pages>319-325</pages><issn>1527-0297</issn><eissn>1557-8682</eissn><abstract>Gross pupil dynamics are used as an indirect measure of brain function. Changes in hypoxia and intracranial pressure are thought to alter pupil responses to light. This study assessed a portable handheld pupil measuring device (pupillometer) in the field investigating the changes in pupil size, speed of reaction, and rate of constriction/dilatation with hypoxia induced by changes in altitude. A correlation between pupil dynamics and acute mountain sickness was sought. Seventeen volunteers were studied following acute exposure to 3450 m and then during a trek to 4770 m in Ladakh, India. The pupillometer was used to record maximum and minimum pupil diameter in response to a standard light source with calculation of latency, constriction and dilatation velocities. Acute mountain sickness (AMS) was recorded using Lake Louise self completed questionnaires both in the morning and afternoon on each day. Acute altitude exposure resulted in a significant reduction of percentage change in pupil size (36.5% to 24.1% p=&lt;0.001), significant delay in pupillary contraction (latency; 0.208 to 0.223 seconds p=0.015) and a significant slowing of the rate of contraction (constriction velocity; -2.77 mm/s to -1.75 mm/s p=0.012). These changes reverted to normal during a period of acclimatization. A significant diurnal variation in pupil size was also observed. There was no significant difference between subjects with and without AMS. The handheld pupillometer is a suitable robust tool for monitoring changes in pupil dynamics in the field. With acute exposure to hypobaric hypoxia associated with an ascent to a moderate altitude, there is a general slowing of pupil function which reverts to normal within a few days of acclimatization. There appears to be a marked diurnal variation in pupil size. The measurements clearly demonstrated an effect of hypoxia on cerebral function, but these changes did not relate to moderate AMS.</abstract><cop>United States</cop><pub>Mary Ann Liebert, Inc</pub><pmid>19115917</pmid><doi>10.1089/ham.2008.1026</doi><tpages>7</tpages></addata></record>
fulltext fulltext
identifier ISSN: 1527-0297
ispartof High altitude medicine & biology, 2008-12, Vol.9 (4), p.319-325
issn 1527-0297
1557-8682
language eng
recordid cdi_gale_infotracmisc_A205747010
source MEDLINE; Alma/SFX Local Collection
subjects Acclimatization - physiology
Acute Disease
Adult
Aged
Altitude
Altitude Sickness - physiopathology
Analysis of Variance
Brain
Diagnostic Techniques, Ophthalmological - instrumentation
Environmental Monitoring - methods
Female
Humans
India
Male
Medical examination
Middle Aged
Mountain sickness
Physiological aspects
Prospective Studies
Pupil (Eye)
Pupil - physiology
Reference Values
Reflex, Pupillary - physiology
Risk factors
title Changes in pupil dynamics at high altitude--an observational study using a handheld pupillometer
url https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-10T13%3A29%3A20IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-gale_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Changes%20in%20pupil%20dynamics%20at%20high%20altitude--an%20observational%20study%20using%20a%20handheld%20pupillometer&rft.jtitle=High%20altitude%20medicine%20&%20biology&rft.au=Wilson,%20Mark%20H&rft.aucorp=Birmingham%20Medical%20Research%20Expeditionary%20Society&rft.date=2008-12-01&rft.volume=9&rft.issue=4&rft.spage=319&rft.epage=325&rft.pages=319-325&rft.issn=1527-0297&rft.eissn=1557-8682&rft_id=info:doi/10.1089/ham.2008.1026&rft_dat=%3Cgale_cross%3EA205747010%3C/gale_cross%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_id=info:pmid/19115917&rft_galeid=A205747010&rfr_iscdi=true