Retina; ChangeNCT02729818
Adaptation Time Required for the Optimisation of Maia Microperimetry Visual Field Testing
An observational study of Retina; Change, run by University of Oxford at 1 site in United Kingdom.
Trial summary
Microperimetry is a relatively new and extremely sensitive method of assessing visual function. It projects light stimuli onto a defined area of the retina to map retinal perceptual thresholds. Participants look at a focal point and press a button to indicate when they have seen a light stimulus. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Retina; Change
- How many people
- 40 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- Feb 2016to Sep 2017
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: Forty healthy adult volunteers (over 18) will be recruited from the University of Oxford. They will need to have healthy eyes and good eyesight (better than 6/7.5 Snellen visual acuity), with no eye diseases apart from refractive error (needing to wear glasses or contact lenses). Participants will need to be able to sit upright at the microperimeter (which involves putting their chin on a chin rest and being able to sit still for up to 20 minutes at a time), and be able to press a button to indicate when they have seen a light stimulus.
Who may be able to join
- Participant is willing and able to give informed consent for participation in the study.
- Male or female.
- Age 18 - 60 years.
- Best corrected visual acuity of at least Logmar 0.1 in right eye.
- Able to tolerate physical requirements of microperimetry testing i.e. able to sit still at the microperimeter in dark environment and indicate when a light stimulus has been seen using the provided button.
Who cannot join
- Any co-existing ocular pathology, either pre-existing or identified on initial ocular examination, not including refractive error or previous cataract surgery
Trial locations and contacts
1 site in 1 country.
United Kingdom1 site
Nuffield Laboratory of Ophthalmology
Oxford, OX3 9DU
About this study
Microperimetry is a relatively new and extremely sensitive method of assessing visual function. It projects light stimuli onto a defined area of the retina to map retinal perceptual thresholds. Participants look at a focal point and press a button to indicate when they have seen a light stimulus. The stimuli vary in intensity to find the participant's visual sensitivity.
Microperimetry is carried out in low light conditions. Before testing, participants must adapt to the low light conditions in a process called 'dark adaptation.' Currently there is no consensus on the optimal time needed for dark adaptation. Investigators know that visual sensitivity differs in differing light conditions. Failing to sufficiently dark-adapt may therefore adversely affect test results.
The aim of this study is to establish the optimal length of dark adaptation for microperimetry performance in healthy volunteers. On day 1, participants will undergo training field tests to reduce a learning effect affecting the results. Tests will then be performed following 5 mins adaptation, 10 mins adaptation and 30mins adaptation, On day 2, participants will perform testing following no adaptation time, 15 mins adaptation, and 20 mins adaptation. Statistics will be used to determine the effect of adaptation time on average threshold measures.
- Conditions
- Retina; Change
- Keywords
- Retina, Microperimetry, Visual Fields
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in average threshold of tests following different dark adaptation periods will be compared.
The average threshold for each test is detailed on the microperimetry printout and is measured in dB. This will be measured by testing following each time interval specified.
Measured: Different time intervals for adaptation prior to testing; 0 minutes, 5, 10, 15, 20 and 30 minutes on day 1 and day 2.
Secondary outcomes (1)
Change in fixation stability, as defined by the area in which 95% of the fixation points for any specific test fall, following different dark adaptation periods will be compared.
The fixation stability for each test is detailed on the microperimetry printout and is measured in degrees for the area covering 95% of the fixation points. This will be measured by testing following each time interval specified.
Measured: Different time intervals for adaptation prior to testing; 0 minutes, 5, 10, 15, 20 and 30 minutes on day 1 and day 2
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Apr 2016 (estimated)
- Study startFeb 2016
- Primary completionSep 2017
- Study completionSep 2017
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Retina; ChangeStudies of the same condition, open and under way.
- More trials run by University of OxfordThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Other
- Time perspective
- Prospective
- Enrolment
- 40 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Oxford
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Jasleen K Jolly, Principal investigator, University of Oxford
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02729818
- Sponsor's protocol ID
- DarkAdapt
- Status last verified
- Oct 2017
- First submitted
- 25 Feb 2016
- Last updated
- 8 Nov 2018
- Results posted
- No
- Data monitoring committee
- No
- Individual data sharing
- Undecided
Publications
Han RC, Gray JM, Han J, Maclaren RE, Jolly JK. Optimisation of dark adaptation time required for mesopic microperimetry. Br J Ophthalmol. 2019 Aug;103(8):1092-1098. doi: 10.1136/bjophthalmol-2018-312253. Epub 2018 Sep 29.
PubMed 30269100
Study at a glance
From the registry record, last updated by the sponsor on 8 Nov 2018. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Adaptation Time Required for the Optimisation of Maia Microperimetry Visual Field Testing
- ClinicalTrials.gov ID
- NCT02729818
- Acronym / sponsor ID
- DarkAdapt
- Conditions
- Retina; Change
- Keywords
- Retina, Microperimetry, Visual Fields
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 40 participants (actual)
- Lead sponsor
- University of OxfordUniversity, hospital or other
- Study start
- Feb 2016 (actual)
- Primary completion
- Sep 2017 (actual)
- Study completion
- Sep 2017 (actual)
- First posted
- 6 Apr 2016 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Microperimetry is a relatively new and extremely sensitive method of assessing visual function. It projects light stimuli onto a defined area of the retina to map retinal perceptual thresholds. Participants look at a focal point and press a button to indicate when they have seen a light stimulus. The stimuli vary in intensity to find the participant's visual sensitivity.
Microperimetry is carried out in low light conditions. Before testing, participants must adapt to the low light conditions in a process called 'dark adaptation.' Currently there is no consensus on the optimal time needed for dark adaptation. Investigators know that visual sensitivity differs in differing light conditions. Failing to sufficiently dark-adapt may therefore adversely affect test results.
The aim of this study is to establish the optimal length of dark adaptation for microperimetry performance in healthy volunteers. On day 1, participants will undergo training field tests to reduce a learning effect affecting the results. Tests will then be performed following 5 mins adaptation, 10 mins adaptation and 30mins adaptation, On day 2, participants will perform testing following no adaptation time, 15 mins adaptation, and 20 mins adaptation. Statistics will be used to determine the effect of adaptation time on average threshold measures.
Study design
- Observational model
- Other
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Forty healthy adult volunteers (over 18) will be recruited from the University of Oxford. They will need to have healthy eyes and good eyesight (better than 6/7.5 Snellen visual acuity), with no eye diseases apart from refractive error (needing to wear glasses or contact lenses). Participants will need to be able to sit upright at the microperimeter (which involves putting their chin on a chin rest and being able to sit still for up to 20 minutes at a time), and be able to press a button to indicate when they have seen a light stimulus.
Key inclusion criteria (5 listed)
- Participant is willing and able to give informed consent for participation in the study.
- Male or female.
- Age 18 - 60 years.
- Best corrected visual acuity of at least Logmar 0.1 in right eye.
- Able to tolerate physical requirements of microperimetry testing i.e. able to sit still at the microperimeter in dark environment and indicate when a light stimulus has been seen using the provided button.
Key exclusion criteria (1 listed)
- Any co-existing ocular pathology, either pre-existing or identified on initial ocular examination, not including refractive error or previous cataract surgery
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Change in average threshold of tests following different dark adaptation periods will be compared.
Time frame: Different time intervals for adaptation prior to testing; 0 minutes, 5, 10, 15, 20 and 30 minutes on day 1 and day 2.
The average threshold for each test is detailed on the microperimetry printout and is measured in dB. This will be measured by testing following each time interval specified.
1 secondary outcome
Change in fixation stability, as defined by the area in which 95% of the fixation points for any specific test fall, following different dark adaptation periods will be compared.
Time frame: Different time intervals for adaptation prior to testing; 0 minutes, 5, 10, 15, 20 and 30 minutes on day 1 and day 2
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Nov 2018.
- Results publication: PubMed 30269100Han RC, Gray JM, Han J, Maclaren RE, Jolly JK. Optimisation of dark adaptation time required for mesopic microperimetry. Br J Ophthalmol. 2019 Aug;103(8):1092-1098. doi: 10.1136/bjophthalmol-2018-312253. Epub 2018 Sep 29.
- Related InfoLink provided by the sponsor.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Jasleen K Jolly principal investigator
University of Oxford
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Retina; Change, run by University of Oxford at 1 site in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 8 Nov 2018. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in average threshold of tests following different dark adaptation periods will be compared. (time frame: Different time intervals for adaptation prior to testing; 0 minutes, 5, 10, 15, 20 and 30 minutes on day 1 and day 2.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT02729818, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Nov 2018.