Sub-threshold frequency doubled Nd. YAG modified mild maculr grid laser for diffuse diabetic maculopathy.

OBJECTIVE: To determine the anatomical and functional improvement in eyes with diffuse macular oedema after modified mild macular grid laser.

METHODS: The prospective study was conducted at the Department of Ophthalmology Unit II, Civil Hospital Karachi, and the Department of Ophthalmology, Dow International Medical College, Karachi, from June 2011 to May 2014. We used neodymium-doped yttrium aluminium garnet 532nm frequency-doubled green laser to treat all eligible patients. Treatment variables were a spot size of 50 microns, exposure duration of 0.1 seconds, and power sufficient to produce barely visible burns in a grid pattern. We treated the thickened retina and non-thickened area of the macula excluding central 500 micron. Microaneurysms within the macular areas were treated by focal application of laser shots sufficient to bleach them.

RESULTS: The study comprised 86 eyes of 52 patients who were treated by applying 180 to 360 burns with a mean of 275±51. Mean macular thickness differed significantly between time points (Wilks' Lambda 0.139; F (2, 6) = 125.95; p = 0.00001). Mean visual acuity changed significantly between time points (Wilks' Lambda 0.535; F (4, 82) = 17.8; p = 0.00001). At the last follow-up, visual acuity improved at least one line in 32(37.2%) eyes, remained stable in 48(55.8%) eyes, and declined in 6(6.9%) eyes.

CONCLUSIONS: Modified mild macular grid is an effective and safe procedure for patients with diffuse diabetic macular oedema.