GLAUCOMA LASER TRIAL
The Glaucoma Laser Trial (GLT) was conducted during 1984-87 to assess the effectiveness of Argon Laser Trabeculoplasty (ALT) in newly diagnosed primary open angle glaucoma patients.
271 patients in the trial randomly underwent ALT in one eye and standard topical treatment in the other eye. The GLT-Followup Study (GLTFS) was a followup study of 203 of the 271 patients who had earlier been enrolled in the GLT. By the end of GLTFS, the patients had been under followup for a median duration of 7 years since the diagnosis of POAG. In GLT each half of the trabecular meshwork was treated with 45-55 laser burns in 2 sessions, 1 month apart. If the IOP was not controlled on followup the medications were changed in the treatment arm or added in the laser group. Further management including surgery was advised on further followup.
As compared with the treated eyes, those which underwent ALT had 1.2 mmHg greater reduction in IOP (P <0.001) and 0.6 dB greater improvement in visual fields (P <0.001). The C:D ratio also showed slightly more worsening [-0.01] (P=0.005) in the treatment group.
In conclusion, ALT was atleast as efficacious as initial treatment with topical medication.