Asymptomatic Narrow Angles - Laser Iridotomy Study; Multicentric RCT

Asymptomatic Narrow Angles Clinical Trial

Official title:

Prophylactic Laser Iridotomy for Eyes With Narrow Drainage Angles; A Randomised Controlled Trial

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT00347178
• Other study ID #: R358/16/2004
• Status: Recruiting
• Phase: N/A
• First received: June 30, 2006
• Last updated: June 30, 2006
• Start date: January 2005
• Est. completion date: January 2013

Study information

• Verified date: June 2006
• Source: Singapore National Eye Centre
• Contact: Tin - Aung, FRCSEd PhD
• Phone: +65 63224581
• Is FDA regulated: No
• Health authority: Singapore: Clinical Trials & Epidemiology Research Unit (CTERU)
• Study type: Interventional

Clinical Trial Summary

This is a multicentric, randomised, controlled study comparing Laser Iridotomy (LI) to no treatment in subjects with asymptomatic narrow angles (ANA).One eye of each subject with ANA will be randomised to undergo LI and the other eye will be left alone and will serve as an internal control. Subjects are proposed to be followed up once a year for 5 years.

Description:

Objective: This study will compare LI versus no treatment in subjects with asymptomatic narrow angles, the anatomical trait that predisposes to primary angle closure glaucoma (PACG), in order to assess the effectiveness of prophylactic treatment in the prevention of blindness due to PACG.

Eligibility: 1. Bilateral Narrow angles; 2. Age 50 years and above; 3. Informed consent obtained prior to or at baseline visit.

Trial Design: Subjects with asymptomatic ANA undergoes randomisation after comprehensive ocular exam followed by randomisation to LI in one eye and no treatment in the other eye. Follow up is done for 5 years with yearly examination.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 544
• Est. completion date: January 2013
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 50 Years and older

Eligibility

Inclusion Criteria:

1. Bilateral Narrow angles

2. Age 50 years and above

3. Informed consent obtained prior to or at baseline visit

Exclusion Criteria:

1. Presence of PAS

2. IOP > 21 mm Hg

3. Glaucomatous optic neuropathy and/or CDR > 0.7

4. Secondary angle closure such as uveitis, neovascularisation etc.

5. Prior intraocular surgery or penetrating eye injury

6. Corneal disorders such as corneal endothelial dystrophy except mild corneal guttae

7. Evidence of prior acute angle closure event

8. High risk of acute angle closure.

9. Significant cataract and visual acuity less than 20/40

10. Constant use of contact lens for refractive correction

11. Chronic use of topical or systemic steroids

12. Established retinopathies on ocular treatments (e.g. Diabetic)

13. Any other disease which is likely to cause field loss in next 3 years

14. Severe health problems decreasing life expectancy to less than one year.

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Prevention

Related Conditions & MeSH terms

• Asymptomatic Narrow Angles
• Primary Angle Closure Suspects

Intervention

Procedure:
• Laser Peripheral Iridotomy

Locations

Country	Name	City	State
Singapore	Singapore Eye Research Institute	Singapore

Sponsors (2)

Lead Sponsor	Collaborator
Singapore National Eye Centre	National Medical Research Council (NMRC), Singapore

Country where clinical trial is conducted

Singapore, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Peripheral anterior synechiae formation
Primary	IOP elevation >21 mm Hg
Primary	Development of acute angle closure event
Secondary	Changes in the grading of Modified Schaffer Grading
Secondary	Development of glaucomatous optic neuropathy
Secondary	Development of corresponding visual field loss by automated perimetry
Secondary	Change in HRT optic disc parameters
Secondary	Change in UBM angle parameters
Secondary	Formation of disc pallor