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Trial registered on ANZCTR

Registration number
Ethics application status
Not yet submitted
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Pupil fatigue: effectiveness of pupil-dilating drops
Scientific title
Effectiveness of mydriatic drops on Dunedin Hospital Eye Department patients, when used on consecutive days
Secondary ID [1] 281379 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Pupil dilation for examination and/or surgery 287606 0
Condition category
Condition code
Eye 287939 287939 0 0
Normal eye development and function

Study type
Description of intervention(s) / exposure
Participants will have pupil diameters measured using an infrared video pupillometer, and then have one drop of either a) tropicamide 1% alone, b) tropicamide 1% and phenylephrine 2.5% a few seconds apart, or c) cyclopentolate 1% and phenylephrine 2.5% a few seconds apart, instilled into one eye.
After an appropriate delay to allow action of the mydriatic agent (30 minutes except for cyclopentolate = 60 minutes), pupillometry will be performed again.
All participants except group c) (the 'control' group) will return the following day to have pupillometry performed again, then one drop each of cyclopentolate 1% and phenylephrine 2.5% will be instilled, and pupillometry repeated after 60 minutes.
Intervention code [1] 285850 0
Treatment: Drugs
Intervention code [2] 285851 0
Early detection / Screening
Comparator / control treatment
Control subjects will have their post-dilation pupil size measured without having had mydriatic drops used the previous day.
Control group

Primary outcome [1] 288147 0
Pupil diameter post-dilation will be measured using an infrared video pupillometer (Neuroptics PLR 200).
Timepoint [1] 288147 0
30 minutes, except for those who received cyclopentolate 1%, who will have pupil diameter measured at 60 minutes
Secondary outcome [1] 299504 0
Increase in pupil diameter post-dilation will be calculated by subtracting pre-dilation pupil diameter (measured by infrared video pupillometer) from post-dilation pupil diameter.
Timepoint [1] 299504 0
60 minutes

Key inclusion criteria
Patients of the Dunedin Hospital Eye Department
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Previous surgery on study eye
On regular eye drops
History of intraocular inflammation in study eye
History of traumatic damage or congenital abnormality of anterior segment of study eye
Narrow drainage angles
Poorly controlled hypertension (>160/90mmHg)
Tachycardia (>90bpm)
Cardiac disease
Allergy to topical agents used in this study
Any physical or cognitive disability that prevents understanding or cooperation with requirements of study

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Participants will be enrolled from those patients being seen at the Dunedin Hospital Eye Department, and will be allocated at random to one of two groups: a control group who will receive mydriatic drops on the study day only, and not be required to return the next day, and a 'treatment' group who will receive one of two combinations of mydriatic drops on the study day, and be required to return the following day for a further round of mydriatic drops. Allocation will not be concealed.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Random number generation by Excel software ((c) Microsoft Corporation, Washington, USA)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment outside Australia
Country [1] 4498 0
New Zealand
State/province [1] 4498 0

Funding & Sponsors
Funding source category [1] 286132 0
Name [1] 286132 0
University of Otago
Address [1] 286132 0
Great King Street
PO Box 913
Dunedin 9054
Country [1] 286132 0
New Zealand
Primary sponsor type
University of Otago
Great King Street
PO Box 913
Dunedin 9054
New Zealand
Secondary sponsor category [1] 284943 0
Name [1] 284943 0
Address [1] 284943 0
Country [1] 284943 0

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 288179 0
Health and Disability Ethics Committee
Ethics committee address [1] 288179 0
Ministry of Health
No 1 The Terrace
PO Box 5013
Wellington 6011
Ethics committee country [1] 288179 0
New Zealand
Date submitted for ethics approval [1] 288179 0
Approval date [1] 288179 0
Ethics approval number [1] 288179 0

Brief summary
This study seeks to determine if the effectiveness of pupil-dilating drops is affected by their use the previous day
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 34603 0
Address 34603 0
Country 34603 0
Phone 34603 0
Fax 34603 0
Email 34603 0
Contact person for public queries
Name 17850 0
Dr Logan Mitchell
Address 17850 0
Department of Medicine
University of Otago Dunedin School of Medicine
Great King St
PO Box 913
Dunedin 9054
Country 17850 0
New Zealand
Phone 17850 0
+64 3 4740999
Fax 17850 0
+64 3 4747641
Email 17850 0
Contact person for scientific queries
Name 8778 0
Dr Logan Mitchell
Address 8778 0
Department of Medicine
University of Otago Dunedin School of Medicine
Great King St
PO Box 913
Dunedin 9054
Country 8778 0
New Zealand
Phone 8778 0
+64 3 4740999
Fax 8778 0
+64 3 4747641
Email 8778 0

No information has been provided regarding IPD availability
Summary results
No Results