Laser therapy in diabetic macular edema

Oman Med J. 2008 Jan;23(1):28-31.

Abstract

Objectives: Diabetic macular edema results in irreversible loss of vision and is the major cause of visual morbidity in patients with Diabetes of adult onset. DCCT trial has linked this to poorer control and increased duration of DM. laser treatment in such cases is known to reduce visual impairment by 50% for a period of 5 years. The aim of this study is to evaluate the effect of laser on visual outcome in patients with clinically significant macular edema and also evaluate the effect of some factors like control of blood sugar, hypertension, nephropathy etc.

Methods: Retrospective analysis of 165 eyes of patients with diabetic maculopathy who underwent laser as per the ETDRS (early treatment diabetic retinopathy study) protocol was made. All these patients underwent Visual Acuity check, slit lamp examination of anterior segment, IOP check and after dilatation detailed examination of macula with 78/90 d lens and areas of retinal thickening recorded and subjected to focal laser/grid laser depending upon whether the maculopathy was focal/diffuse. Patients were assessed for control of sugar and presence of hypertension/nephropathy or any other related systemic diseases. Patients were followed up for a minimum of 6 months to a maximum of 24 months. The visual acuity at the end of 3-4 months was taken as final visual acuity after laser.

Results: 165 eyes of patients having CSME (clinically significant macular edema) were subjected to laser. 108 (64.54%) eyes underwent focal laser and the rest were given grid laser. 153 eyes underwent macular laser without PRP (Pan retinal photocoagulation) while rest had even PRP along with macular laser. 92 eyes (55.75%) totally, 39 eyes (59.1%) in controlled group and 26 eyes (56.5%) in the controlled group and 12 eyes (54.5%) in patients with hypertension had stable vision 3-4 months after laser. 44 eyes (26.7%) overall, 18 eyes (27.3%) in controlled group, 16 eyes (34.8%) in uncontrolled group and 7 eyes (31.8%) in hypertensive showed improvement of vision after laser.

Conclusion: More than 50% of eyes of patients who underwent laser had stabilization of VA and >25% of eyes had improvement in VA. No correlation was found between outcome of laser and control of blood sugar and associated hypertension.

Keywords: CSME; ETDRS (early treatment diabetic retinopathy study); Focal laser; Grid laser.