Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12622000737730p
Ethics application status
Submitted, not yet approved
Date submitted
30/03/2022
Date registered
23/05/2022
Date last updated
23/05/2022
Date data sharing statement initially provided
23/05/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
Examining the effect of superior vs temporal laser peripheral iridotomy in adults with primary angle-closure glaucoma or angle-closure suspect
Scientific title
Dysphotopsia following superior versus temporal laser peripheral iridotomy for treating eyes with narrow anterior chamber angle
Secondary ID [1] 306811 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
primary angle-closure glaucoma 325891 0
primary angle-closure suspect 325892 0
Condition category
Condition code
Eye 323199 323199 0 0
Diseases / disorders of the eye

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Neodymium-doped yttrium aluminium garnet (Nd:YAG) laser (Ellex Tango) will be used to perform the laser peripheral iridotomy procedure. One eye for each participant will undergo superior placement of the iridotomy hole and the other eye assigned temporal/nasal placement of the iridotomy hole. The procedure will be done at a private Sydney ophthalmology clinic by an experienced ophthalmologist. The procedure usually takes 5-10 minutes after which participants may return home. Participants included in the study will have one eye undergo superiorly placed laser peripheral iridotomy and the other assigned to temporal location by default. The procedure will be performed sequentially with the superior laser peripheral iridotomy (LPI) performed first. The selected eye will be based on presenting symptoms - in the eye with poorer visual acuity, clinically narrower angles and/or smaller anterior chamber depth. Within one week, the participant will undergo the second LPI performed temporally/nasally. Adherence to the intervention will be monitored using clinical notes.
Intervention code [1] 323272 0
Treatment: Other
Comparator / control treatment
The comparator/control will be the patient's own eye that has undergone superior placement of laser peripheral iridotomy.
Control group
Active

Outcomes
Primary outcome [1] 330951 0
The presence of dysphotopsia symptoms will be self-reported by participants using a standardised questionnaire at follow up appointments. The questionnaire is designed specifically for this study.
Timepoint [1] 330951 0
1 month and 6 months post-procedure
Secondary outcome [1] 408226 0
Laser parameters including iridotomy hole size (in mm), number of shots used, and total laser energy used (kJ) will be documented during the procedure as per procedure protocol. An audit of study records will be performed retrospectively to collect this data.

Timepoint [1] 408226 0
Intraoperative
Secondary outcome [2] 408227 0
Post-procedure intraocular pressure (IOP) using tonometer
Timepoint [2] 408227 0
Pre-procedure, at 1 month and 6 months post-procedure
Secondary outcome [3] 408228 0
Incidence of post-procedure complications including transient post-op increase in IOP (using tonometer), iris bleeding (assessed by slit lamp examination) and occluded LPIs (determined by post-procedure IOP measured using tonometer) post-procedure requiring repeat LPI
Timepoint [3] 408228 0
1 month and 6 months post-procedure
Secondary outcome [4] 409056 0
Visual acuity using Snellen Chart
Timepoint [4] 409056 0
Pre-procedure, 1 month and 6 months post-procedure

Eligibility
Key inclusion criteria
1) Participants (>18 years old) diagnosed with primary angle closure glaucoma or primary angle-closure suspect in both eyes and requiring laser peripheral iridotomy intervention
2) Participants are able to attend required study visits
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1) Participants who have undergone previous laser peripheral iridotomy procedure in either eye
2) Participants who have undergone previous intraocular surgery
3) Participants with asymmetrical ptosis of more than 2mm
4) Participants with any active intraocular inflammation at the time of undergoing laser peripheral iridotomy procedure
5) Participants with a history of acute-attack angle closure glaucoma

Study design
Purpose of the study
Treatment
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
Not Applicable
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
25/05/2022
Actual
Date of last participant enrolment
Anticipated
25/05/2023
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
138
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 311147 0
Self funded/Unfunded
Name [1] 311147 0
Country [1] 311147 0
Primary sponsor type
Individual
Name
Rachel Xuan
Address
Dr Keith Ong Ophthalmology
2 Railway Avenue EASTWOOD NSW 2122
Country
Australia
Secondary sponsor category [1] 312495 0
None
Name [1] 312495 0
N/A
Address [1] 312495 0
N/A
Country [1] 312495 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 310675 0
Northern Sydney Local Health District Human Research Ethics Committee
Ethics committee address [1] 310675 0
Executive Unit, Level 14, Kolling Building, Royal North Shore Hospital,
Reserve Road, St Leonards NSW 2065
Ethics committee country [1] 310675 0
Australia
Date submitted for ethics approval [1] 310675 0
30/03/2022
Approval date [1] 310675 0
Ethics approval number [1] 310675 0

Summary
Brief summary
Laser peripheral iridotomy is used to treat narrow and closed-angle glaucoma and eyes with narrow anterior chamber angle to prevent progression to glaucoma. The laser peripheral iritodomy can be done in any location in the peripheral iris, however traditionally, it has been performed in the superior 12 o’clock position. The superior and temporal (3 o’clock for left eye, 9 o’clock for right eye) sites are the most common sites for laser peripheral iridotomy.

Rarely, some patients may experience visual disturbances after laser peripheral iridotomy. These are known as dysphotopsia symptoms and typically described as grey or blue horizontal or slightly curved line.

The purpose of this study is to assess the whether superior or temporal placement the iridotomy hole is associated with incidence of dysphotopsia symptoms. The hypothesis is that superiorly placed laser peripheral iridotomies are associated with reduced incidence of dysphotopsia symptoms.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 118478 0
Dr Rachel Xuan
Address 118478 0
Dr Keith Ong Ophthalmology
2 Railway Avenue, EASTWOOD NSW 2122
Country 118478 0
Australia
Phone 118478 0
+61 02 9858 3949
Fax 118478 0
Email 118478 0
rachel.xuan@health.nsw.gov.au
Contact person for public queries
Name 118479 0
Dr Rachel Xuan
Address 118479 0
Dr Keith Ong Ophthalmology
2 Railway Avenue, EASTWOOD NSW 2122
Country 118479 0
Australia
Phone 118479 0
+61 02 9858 3949
Fax 118479 0
Email 118479 0
rachel.xuan@health.nsw.gov.au
Contact person for scientific queries
Name 118480 0
Dr Rachel Xuan
Address 118480 0
Dr Keith Ong Ophthalmology
2 Railway Avenue, EASTWOOD NSW 2122
Country 118480 0
Australia
Phone 118480 0
+61 02 9858 3949
Fax 118480 0
Email 118480 0
rachel.xuan@health.nsw.gov.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Participant data collected will be de-identified prior to analysis. Analysis performed will collate individual participant data. This will be not be shared with other researchers.


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.