Clear Vision Study

Randomized Trial of Laser Ablation for Highly Symptomatic Floaters

Vitreous floaters are tiny, cloudy, clumps of cells that appear in the otherwise clear fluid (vitreous) that fills the back 3/4 of the eye. Floaters are commonly caused by eye conditions such as posterior vitreous detachment (PVD), vitreous syneresis and asteroid hyalosis. While these symptoms are considered physiological in nature, they can be of considerable inconvenience to many patients which affect essential activities. The investigators wish to assess the safety and efficacy of floater treatment in patients with highly symptomatic floaters using an FDA approved nanosecond infrared yttrium aluminum garnet (YAG) lasers.

Study Overview

• Status: Completed
• Conditions: Posterior Vitreous Detachment; Vitreous Floaters
• Intervention / Treatment: Procedure: Laser Ablation of Floaters; Procedure: Sham Laser Treatment

• Study Type: Interventional
• Enrollment (Actual): 35
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • British Columbia
    • Vancouver, British Columbia, Canada, V5Z 1K1
      • West Coast Retina Consultants Clinic
    • Vancouver, British Columbia, Canada, V5Z 3N9
      • Eye Care Centre, Vancouver General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 17 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Have been diagnosed with symptomatic floaters lasting more than 2 months
• Willing to proceed with intervention
• Be able to provide informed consent
• Diagnosed with Posterior Vitreous Detachment
• Accept a 1% risk of complications

Exclusion Criteria:

• Less than 19 years of age
• Is a high myope (greater than -6 diopters)
• Has monocular vision
• Diagnosed with asteroid hyalosis
• Diagnosed with acute on-set of floaters (less than two months and may clear spontaneously)
• Has corneal or lenticular opacities or any media opacity which may interfere with treatment
• Has any concomitant ocular disease or pathology
• Has elevated intraocular pressure (IOP) or on IOP lowering medication
• Has floaters that are deemed to require more than five treatment sessions, where surgical intervention is the best treatment course
• Has floaters inaccessible with current lasers and lenses
• Has floaters located less than 2mm from the crystalline lens or the retina
• Found to have retinal tears or retinal detachment on initial examination or has had a history of retinal detachment repair within the last two years
• Has psychiatric problems that may recur or worsen
• Incapacity to provide informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Laser Treated; Laser will direct the laser at vitreous opacities. The power of the laser will be adjusted from 0.3-12 millijoules (mJ) with the end point being laser induced optical breakdown and the production of a small gas bubble 50% of the time. The treatment will attempt to reduced or eliminate symptomatic floaters in the visual axis. Each treatment session will be limited to 300 laser applications. Participants will be retreated based on continued symptoms for up to 5 sessions	Procedure: Laser Ablation of Floaters
Sham Comparator: Not Treated	Procedure: Sham Laser Treatment; Laser will be set at 0.3 millijoules (mJ). There will be a 100% absorptive filter (black spot) of about 1cm placed centrally on the lens. All laser aiming beams will be placed within the 1cm filter. Laser will be applied at 0.3 mJ at the absorptive black spot (100% density filter) in order to create a realistic treatment therapy procedure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Efficacy of the laser treatment measured by the improvement of visual acuity and floater specific Visual Function Questionnaire (VFQ).	after the last treatment session (approximately 5 days)

Secondary Outcome Measures

Outcome Measure	Time Frame
Number of complications in the laser treated eyes compared to the non-treated eyes	6 months

Collaborators and Investigators

• Sponsor: University of British Columbia
• Investigators: Study Chair: Andrew B Merkur, MD, University of British Columbia; Study Director: Mei Young, MASc, University of British Columbia

Study record dates

Study Major Dates

• Study Start: October 1, 2013
• Primary Completion (Actual): February 1, 2016
• Study Completion (Actual): February 1, 2016

Study Registration Dates

• First Submitted: October 22, 2013
• First Submitted That Met QC Criteria: October 25, 2013
• First Posted (Estimate): October 28, 2013

Study Record Updates

• Last Update Posted (Estimate): April 21, 2016
• Last Update Submitted That Met QC Criteria: April 20, 2016
• Last Verified: April 1, 2016

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Vitreous Detachment
• Other Study ID Numbers: H13-01836

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No