SLTRepeat: A Trial to Compare the Laser Treatment (SLT vs. ALT) in Glaucoma Patients

Sponsor

Lawson Health Research Institute (Other)

Overall Status

Unknown status

CT.gov ID

NCT01687465

Collaborator

(none)

139

Enrollment

Locations

Arms

63.9

Duration (Months)

19.9

Patients Per Site

0.3

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Lasers are important therapy in glaucoma. They are a pivotal point in treatment between medical and surgical care. Over the last 10 years a new laser has emerged as the usual laser treatment: Selective laser trabeculoplasty (SLT). SLT works as well as the older laser used: argon laser trabeculoplasty (ALT). However SLT has many theoretical benefits over ALT including causing less damage to the tissue it affects. One of the potential patient centered benefits of this laser is that it may be repeatable. It is even possible that the old laser ALT may be useable after an SLT treatment. This study aims to uncover whether repeat laser is possible after SLT and if so which laser is more effective (ALT vs SLT). The potential of repeating laser therapies may delay surgical treatment and its complications. Also understanding which laser to use will help eye doctors know how to treat their patients at this point of the disease.

Condition or Disease	Intervention/Treatment	Phase
Glaucoma	Procedure: Argon laser trabeculoplasty Procedure: Selective laser trabeculoplasty	Phase 3

Study Design

Study Type:

Interventional

Actual Enrollment :

139 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Single (Participant)

Primary Purpose:

Treatment

Official Title:

A Randomized Clinical Trial of Selective Laser Trabeculoplasty (SLT) in Open Angle Glaucoma Who Had Been Previously Treated With Complete SLT

Study Start Date :

Nov 1, 2012

Anticipated Primary Completion Date :

Mar 1, 2018

Anticipated Study Completion Date :

Mar 1, 2018

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: Argon laser trabeculoplasty Up to the year 2005, the vast majority of ophthalmologists used Argon laser trabeculoplasty (ALT) as the mode of laser therapy. ALT is effective but its most significant problem is that its effectiveness decreases with re-treatment since the tissue it targets (the trabecular meshwork) is changed by the laser rendering repeat treatments less effective.	Procedure: Argon laser trabeculoplasty With Argon laser trabeculoplasty (ALT), thermal energy is used directed towards the Trabecular Meshwork (the site of aqueous drainage from the eye),which causes focal scarring of trabecular meshwork, thus enable fluid drainage more effectively. However, this procedure may not be repeatable since it causes too much damage to the trabecular meshwork. Procedure: Selective laser trabeculoplasty Selective laser trabeculoplasty is a relatively newer technology that uses a Nd:YAG laser to target specific cells within the trabecular meshwork. SLT does not cause coagulative damage to the trabecular meshwork, and thus has the advantage of being repeatable.
Active Comparator: selective laser trabeculoplasty Post 2005, a newer mode of laser therapy, selective laser trabeculoplasty (SLT) has emerged as the standard of care laser. There are many potential advantages to SLT but to date these advantages are only theoretical. The most important potential clinical advantage of SLT is that it causes less damage to the tissue it targets.	Procedure: Argon laser trabeculoplasty With Argon laser trabeculoplasty (ALT), thermal energy is used directed towards the Trabecular Meshwork (the site of aqueous drainage from the eye),which causes focal scarring of trabecular meshwork, thus enable fluid drainage more effectively. However, this procedure may not be repeatable since it causes too much damage to the trabecular meshwork. Procedure: Selective laser trabeculoplasty Selective laser trabeculoplasty is a relatively newer technology that uses a Nd:YAG laser to target specific cells within the trabecular meshwork. SLT does not cause coagulative damage to the trabecular meshwork, and thus has the advantage of being repeatable.

Arm

Intervention/Treatment

Active Comparator: Argon laser trabeculoplasty

Up to the year 2005, the vast majority of ophthalmologists used Argon laser trabeculoplasty (ALT) as the mode of laser therapy. ALT is effective but its most significant problem is that its effectiveness decreases with re-treatment since the tissue it targets (the trabecular meshwork) is changed by the laser rendering repeat treatments less effective.

Procedure: Argon laser trabeculoplasty

With Argon laser trabeculoplasty (ALT), thermal energy is used directed towards the Trabecular Meshwork (the site of aqueous drainage from the eye),which causes focal scarring of trabecular meshwork, thus enable fluid drainage more effectively. However, this procedure may not be repeatable since it causes too much damage to the trabecular meshwork.

Procedure: Selective laser trabeculoplasty

Selective laser trabeculoplasty is a relatively newer technology that uses a Nd:YAG laser to target specific cells within the trabecular meshwork. SLT does not cause coagulative damage to the trabecular meshwork, and thus has the advantage of being repeatable.

Active Comparator: selective laser trabeculoplasty

Post 2005, a newer mode of laser therapy, selective laser trabeculoplasty (SLT) has emerged as the standard of care laser. There are many potential advantages to SLT but to date these advantages are only theoretical. The most important potential clinical advantage of SLT is that it causes less damage to the tissue it targets.

Procedure: Argon laser trabeculoplasty

Procedure: Selective laser trabeculoplasty

Outcome Measures

Primary Outcome Measures

Intraocular Pressure [12 months post operatively]
IOP difference between baseline and 12 month post-laser.

Secondary Outcome Measures

To compare the IOP lowering effect between the groups at other postoperative visits [12 months]
IOP difference between baseline, 1hr, 1 wk, and 1, 3, 6 and 12 mon post-laser.
To compare the visual acuity between the groups at all visits. [12 months]
VA difference between baseline, 1hr, 1 wk, and 1, 3, 6 and 12 mon post-laser.
To compare the trabecular meshwork pigmentation between the groups at all visits. [12 months]
To compare any adverse events between the two groups at all visits. [12 months]
SLT repeatability of long term follow up in glaucoma patients [36 months after initial enrollment of the primary study]
The follow up time has been extended two more years. Patients will be followed up Q6 months.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Over age of 18 yo.
OAG including pigmentary dispersion syndrome and pseudoexfoliation
OAG has been treated with 360 degrees of SLT
two sighted eyes,
willing to participate after being informed of and reading the patient information material.

Exclusion Criteria:

Narrow angle glaucoma
Previous glaucoma surgery
Eye surgery expected in the next 12 months
Severe corneal disease
On or anticipated steroid in 6 months
Pregnant or breast feeding

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Rockyview General Hospital, University of Calgary	Calgary	Alberta	Canada	T3E 7M8
2	Royal Alexandra Hospital, University of Alberta	Edmonton	Alberta	Canada	T5H 3V9
3	Eye Care Centre, Dalhousie University	Halifax	Nova Scotia	Canada	B3H2R1
4	McMaser University, St. Joseph's Healthcare Hamilton, CAHS Regional Eye Institute	Hamilton	Ontario	Canada	L8G 5E4
5	Ivey Eye Institute, St. Joseph's Hospital, Western University	London	Ontario	Canada	N6A 4V2
6	Sunnybrook Health Sciences Centre, University of Toronto	Toronto	Ontario	Canada	M4N 3M5
7	McGill University, Dept. of Ophthalmology, Royal Victoria Hospital,	Montreal	Quebec	Canada	H3A 1A1