Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12619000463178
Ethics application status
Approved
Date submitted
15/03/2019
Date registered
20/03/2019
Date last updated
20/03/2019
Date data sharing statement initially provided
20/03/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
The role of optical and non optical factors to provide a directional information to the focusing mechanism (Accommodation) of the eye in young adults.
Scientific title
Utility of optical and non-optical cues by the accommodative system to decode the
sign of defocus in young adults
Secondary ID [1] 297711 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Myopia 312034 0
Hyperopia 312035 0
Emmetropia 312036 0
Ocular accommodation 312037 0
Condition category
Condition code
Eye 310601 310601 0 0
Normal eye development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This is a prospective cross sectional observational study design. There will be 3 visits comprising baseline and two visits to assess the ocular accommodation. The duration between each visit can range from 3 days to 7 days. Short term accommodative measurements as done in this study (e.g. 45 minutes to 60 minutes with regular intervals of breaks) are not influenced by duration between the measurements given it is more than a day. However, we chose this specific time range to balance the measurement consistency and the participant’s feasibility. All visits including the contact lens assessment will be performed by an optometrist and will be approximately 60 minutes in duration.

Baseline visit will comprise visual acuity assessment and accommodative-convergence responses with habitual refractive correction. Auto-refraction, subjective refraction with visual acuity measurement and ocular assessment with a slitlamp bio microscope (a specialized microscope for viewing the eye) will be performed with no contact lens on eye. Rest of the study visits will have the accommodative measurements using a non-contact binocular open field autorefractor. In the final visit the participant will be asked to wear a custom designed coloured soft contact lens (a clear transparent centre zone, which is surrounded by a wide black ring to block out all light outside the central vision-pinhole contact lens) in order to correct the optical aberrations of the eye. The purpose of the soft contact lens is solely to correct the monochromatic aberration but not to evaluate the efficacy/effect of the contact lens in any manner. This contact lens otherwise would act like the spectacle lens/regular contact lens to correct the refractive error with an added advantage of correcting the optical aberrations. The pinhole approach to correct the monochromatic aberrations has been well established in the literature. There are no associated risks involved with these procedures. However the contact lens use might cause minor ocular discomfort which includes tearing, burning sensation. But, that is the normal protective mechanism of the eye and the symptoms will reduce by its own in 5-10 min times. This is naturally experienced by any naive contact lens wearer. An adequate time will be given to the participant to adapt for the lenses. In case of the persistent symptoms Optometry clinic staff will be there to assist with the necessary care.This contact lens fitting will be assessed by an Optometrist and appropriate adaptation time will be given to the participant before commencing any measurements. The lens is worn for short duration and each lens is disposed after the use.

The accommodation will be measured while the participant is asked to look at the target presented on the computer screen. The screen is placed in front of the participant’s primary gaze position. The target will be varied in size and colour while the participant task is to maintain a fixation on the target. The participant will be given regular verbal instructions to maintain the fixation. The participant can also blink normally while the measurement in progress.
Intervention code [1] 313984 0
Treatment: Devices
Comparator / control treatment
no control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 319459 0
Accommodative response changes with target ( non optical) characteristics: (Composite primary outcome-1)
The target (Alphabets used in the routine eye examination) characteristics include:
Different size ( equal to 20/20 to 2/60 letter height in visual acuity chart)
Different speed of movement (0.2 , 0.4and 0.6D/s)

Above mentioned target factors will be altered using a computer display placed in primary gaze of the participant. The participant will be asked to place the chin on the autorefractor chin rest and the measurements will be taken while the participant fixates the target.
Timepoint [1] 319459 0
Baseline visit and Visit 2 ( 3-5 days after the baseline visit )
Primary outcome [2] 319496 0
Accommodation response change with optical factors include;(Composite primary outcome-2)
Monochromatic and chromatic aberration correction

The role of chromatic aberration will be assessed by presenting red, green and blue coloured targets separately and compare the accommodative response with white colored target.
The role of monochromatic aberrations will be assessed by asking the participant to fixate at a constant target (Maltese cross) and the accommodation will be measured with and without the pinhole aperture ( coloured ) contact lens,
In both the conditions, the measurement set up and the instructions given to the participant remain same.
Timepoint [2] 319496 0
Visit 3 (3- 5 days after the visit 2)
Secondary outcome [1] 368470 0
Nil
Timepoint [1] 368470 0
Nil

Eligibility
Key inclusion criteria
Able to read and comprehend English and give informed consent as demonstrated by signing a record of informed consent.
Be between 18-30 years old, male or female.
Willing to comply with the clinical trial as directed by the Investigator.
Have ocular health findings considered to be “normal” and which would not prevent the participant from safely wearing contact lenses.
Be an emmetrope (+0.50 DS to -0.50 DS), hyperope(+0.75 DS to +6.00 DS) or a myope (-0.75 DS to -6.00 DS) with or without astigmatism less than =<1.00DC
Be correctable to better than 0.20 log MAR in each eye with single vision contact lenses.
Be able to insert and remove contact lenses.
Minimum age
18 Years
Maximum age
30 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Any pre-existing ocular irritation, injury or condition (including infection or disease) of the cornea,
conjunctiva or eyelids that would preclude contact lens fitting and safe wearing of contact lenses.
Any systemic disease that adversely affects ocular health e.g. diabetes, Graves disease, and auto immune diseases such as ankylosing spondylitis, multiple sclerosis, Sjogrens syndrome and systemic lupus erythematosus.
Conditions such as systemic hypertension and arthritis do not automatically exclude prospective participants.
Use of or a need for any systemic medication or topical medications which may alter normal ocular
findings / are known to affect a participant’s ocular health / physiology or contact lens performance either in an adverse or beneficial manner at enrolment and/or during the clinical trial.
Previous corneal refractive surgery.
Previous surgery on the extra ocular muscles.
Contraindications to contact lens wear.
Known allergy or intolerance to ingredients in any of the clinical trial products.
Currently enrolled in another clinical trial.
Pregnancy*.
The Investigator may, at his discretion, exclude anyone who they believe may not be able to fulfil the
clinical trial requirements or it is believed to be in the participant’s best interests.
*Formal testing of pregnancy is not required. A participant’s verbal report is sufficient.

Study design
Purpose of the study
Diagnosis
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Type of endpoint/s
Statistical methods / analysis
Previous studies have reported a standard deviation of 0.28D for differences between accommodative measurements with various testing conditions. Considering a clinically significant difference of 0.5D, a sample of 10 participants in each refractive error group will have 80% power at the 5% level of significance to detect a paired difference of 0.5±0.5D between stimulus conditions, Our study will include a minimum of 30 participants including subgroups of emmetropia (refractive error ranging from +0.50 D to -0.50 D), hyperopia( refractive error greater than +0.50 D) and myopia (refractive error greater than -0.50 D).
The primary outcome variable ( accommodative response) will be compared between the different target presentations. The mean accommodative response will be compared to find the statistical significance and post hoc multiple comparisons will be adjusted using Bonferroni correction.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
26/03/2019
Actual
Date of last participant enrolment
Anticipated
31/05/2020
Actual
Date of last data collection
Anticipated
31/05/2020
Actual
Sample size
Target
30
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 302236 0
Charities/Societies/Foundations
Name [1] 302236 0
Brien Holden Vision Institute
Country [1] 302236 0
Australia
Primary sponsor type
Charities/Societies/Foundations
Name
Brien Holden Vision Institute
Address
Level 4, Rupert Myers Building Gate 14, Barker
Street University of New South Wales, NSW
2052
Country
Australia
Secondary sponsor category [1] 302090 0
None
Name [1] 302090 0
Address [1] 302090 0
Country [1] 302090 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 302914 0
University of New South Wales Human Research Ethics Committee
Ethics committee address [1] 302914 0
UNSW Research Ethics & Compliance Support
The University of New South Wales
Sydney NSW 2052 Australia
Ethics committee country [1] 302914 0
Australia
Date submitted for ethics approval [1] 302914 0
07/08/2018
Approval date [1] 302914 0
04/10/2018
Ethics approval number [1] 302914 0

Summary
Brief summary
The purpose of this study is to assess how the accommodative system (the focusing mechanism) of the eye extracts the directional information from the visual experience, We will be assessing the accommodative system function using a non-contact instrument where you are asked to look at a target provided on a computer screen.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 91830 0
Dr Ravi Bakaraju
Address 91830 0
Head, Research & Development, Brien Holden Vision Institute
Senior Lecturer, a conjoint appointee, School of Optometry and Vision Science,
Level 4, North Wing, RMB, Gate 14, Barker Street UNSW SYDNEY NSW 2052 Australia
Country 91830 0
Australia
Phone 91830 0
+61 2 93857455
Fax 91830 0
Email 91830 0
r.bakaraju@unsw.edu.au
Contact person for public queries
Name 91831 0
Mr Praveen Bandela
Address 91831 0
Praveen Bandela
Level 4, North Wing, RMB, Gate 14,
Barker Street UNSW SYDNEY NSW 2052 Australia
Country 91831 0
Australia
Phone 91831 0
+61 2 93857535
Fax 91831 0
Email 91831 0
p.bandela@brienholdenvision.org
Contact person for scientific queries
Name 91832 0
Mr Praveen Bandela
Address 91832 0
Praveen Bandela
Level 4, North Wing, RMB, Gate 14,
Barker Street UNSW SYDNEY NSW 2052 Australia
Country 91832 0
Australia
Phone 91832 0
+61 2 93857535
Fax 91832 0
Email 91832 0
p.bandela@brienholdenvision.org

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.