Glaucoma Laser Trial (GLT) Glaucoma Laser Trial Followup Study (GLTFS)

NCT ID: NCT00000144

Last Updated: 2006-06-05

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

PHASE3

Study Classification

INTERVENTIONAL

Study Start Date

1984-01-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

To compare the safety and long-term efficacy of argon laser treatment of the trabecular meshwork with standard medical treatment for primary open-angle glaucoma.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

During the last decade, argon laser trabeculoplasty (ALT) has often been used instead of surgery as the treatment of choice in cases of open-angle glaucoma that could not be controlled by drugs. ALT treatment consists of tiny laser burns evenly spaced around the trabecular meshwork. It sometimes has been found to be effective in controlling glaucoma, although many eyes still require some medical treatment.

The Glaucoma Laser Trial (GLT), a randomized, controlled clinical trial, was conducted to determine whether ALT is effective in patients with newly diagnosed, primary, open-angle glaucoma. Each of the 271 patients in the trial received argon laser treatment in one eye and standard topical medication in the other eye. The eye to be started on medicine and the eye that would get the laser treatment were randomly selected. The Glaucoma Laser Trial Followup Study was a followup study of 203 of the 271 patients who enrolled in the Glaucoma Laser Trial. By the close of the Glaucoma Laser Trial Followup Study, median duration of followup since diagnosis of primary, open-angle glaucoma was 7 years (maximum, 9 years).

The argon laser treatment was done in two sessions 1 month apart, with one-half of the trabecular meshwork treated with 45 to 55 laser burns in each session. Patients were seen for a followup visit 3 months after the first laser treatment and every 3 months thereafter for a period of at least 2 years. At each visit, examination of the eyes included a check of intraocular pressure and visual acuity. Visual field examinations were performed 3, 6, and 12 months after randomization and annually thereafter. Disc stereo photographs were taken 6 and 12 months after randomization and annually thereafter.

The results of these examinations determined whether treatment should be changed. If the pressure in either eye had not been reduced to the desired level, the physician changed the medication in the eye treated with drops or started the use of drops in the laser-treated eye according to a standardized procedure being used in the trial. If intraocular pressure was still not successfully reduced, surgery or further laser treatment may have been required.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Open-Angle Glaucoma

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Primary Study Purpose

TREATMENT

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Argon Laser Treatment

Intervention Type PROCEDURE

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

At the time of recruitment, patients had to be at least 35 years old with an intraocular pressure of at least 22 mm Hg or greater in each eye and evidence of optic nerve damage in at least one eye.
Minimum Eligible Age

35 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

National Eye Institute (NEI)

NIH

Sponsor Role lead

References

Explore related publications, articles, or registry entries linked to this study.

The Glaucoma Laser Trial (GLT). 2. Results of argon laser trabeculoplasty versus topical medicines. The Glaucoma Laser Trial Research Group. Ophthalmology. 1990 Nov;97(11):1403-13.

Reference Type BACKGROUND
PMID: 2255512 (View on PubMed)

The Glaucoma Laser Trial (GLT): 3. Design and methods. Glaucoma Laser Trial Research Group. Control Clin Trials. 1991 Aug;12(4):504-24. doi: 10.1016/0197-2456(91)90010-j.

Reference Type BACKGROUND
PMID: 1657527 (View on PubMed)

The Glaucoma Laser Trial: 4. Contralateral effects of timolol on the intraocular pressure of eyes treated with ALT. GLT Research Group. Ophthalmic Surg. 1991 Jun;22(6):324-9.

Reference Type BACKGROUND
PMID: 1896168 (View on PubMed)

The Glaucoma Laser Trial (GLT): 5. Subgroup differences at enrollment. Glaucoma Laser Trial Research Group. Ophthalmic Surg. 1993 Apr;24(4):232-40.

Reference Type BACKGROUND
PMID: 8321504 (View on PubMed)

The Glaucoma Laser Trial (GLT): 6. Treatment group differences in visual field changes. Glaucoma Laser Trial Research Group. Am J Ophthalmol. 1995 Jul;120(1):10-22. doi: 10.1016/s0002-9394(14)73754-7.

Reference Type BACKGROUND
PMID: 7611312 (View on PubMed)

The Glaucoma Laser Trial (GLT) and glaucoma laser trial follow-up study: 7. Results. Glaucoma Laser Trial Research Group. Am J Ophthalmol. 1995 Dec;120(6):718-31. doi: 10.1016/s0002-9394(14)72725-4.

Reference Type BACKGROUND
PMID: 8540545 (View on PubMed)

The Glaucoma Laser Trial. I. Acute effects of argon laser trabeculoplasty on intraocular pressure. Glaucoma Laser Trial Research Group. Arch Ophthalmol. 1989 Aug;107(8):1135-42.

Reference Type BACKGROUND
PMID: 2667508 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

NEI-43

Identifier Type: -

Identifier Source: org_study_id