Panretinal photocoagulation is a vital tool for treating diabetic retinopathy, but it can also affect macular pigment optical density (MPOD), according to a recent study. Researchers evaluated the effects of panretinal photocoagulation treatment on MPOD, since macular pigment has essential functions for the retina, including protective and antioxidant properties.

The prospective clinical study employed the color perimetry method to measure MPOD and include 36 eyes of 36 patients with severe non-proliferative DR without macular involvement. The patients underwent panretinal photocoagulation at baseline and one, two and three months for those who required the treatment. MPOD and retinal thickness were measured at baseline and at months one, two, three and six.

The researchers found that over a period of six months, MPOD reduction in the fovea was 0.02±0.02 logarithmic units. The pericentral areas also declined by 0.04±0.03 logarithmic units. Mean central macular thickness and foveal thickness increased by 5.03±5.02μm and 2.78μm, respectively.

The researchers noted that panretinal photocoagulation laser energy applied to the eye was significantly and strongly correlated with reductions in MPOD, as well as with central macular thickness and fovea thickness. They concluded that panretinal photocoagulation may cause a decrease in macular pigment density proportional to the amount of laser energy applied to the eye.

Dogan M and Kutluksaman B. Macular pigment optical density after panretinal photocoagulation. Clin Exp Optom. August 31, 2020. [Epub ahead of print].