Retinal Functional Improvement With Nano-laser Treatment In High Risk Early Age-related Macular Degeneration

Abstract

 

Purpose:

 

The aim of this pilot study was to show if a novel nanosecond laser (2RT) treatment could improve visual function and reduce drusen in high risk Early Age-related Macular Degeneration (AMD), which may then lead to reduced risk of late stage AMD.

 

Methods:

 

Interim results out t o12 months from a prospective pilot study (ACTRN12609001056280). Early AMD patients selected with high risk Early AMD but without choroidal neovascularization (CNV) or geographic atrophy (GA). Patients examined with visual field perimeter, optical coherence tomography (OCT), auto-fluorescence (AF) imaging, fundus photography, visual acuity). Laser treatment consisted of 12 single laser pulses of 3ns duration, placed in "clock face" pattern around the mid-macular (5deg radius) of one eye using an energy range of 0.15mJ to 0.45mJ , spot diameter of 400µm, wavelength of 532nm. The patient’s eye with highest risk was treated and main follow-up was performed at 3, 6 and 12mths. Visual field results were used to determine the bilateral regions of greatest dysfunction.

 

Results:

 

13 of the 14 patients that have reached 12mth follow-up showed some level of visual function improvement or drusen reduction, in one or both eyes. The regions of greatest dysfunction in visual function improved significantly in 7 of these patients and the majority of improvement occurred in patients with the greatest pre-treatment dysfunction. VA significantly improved (>5 letters) in 5 patients and some level of drusen reduction occurred in 13 of the patients in one or both eyes. No association was evident between the location of visual function improvements and the location of the laser treatment or the eye treated. Decreased function or other adverse events did not occur in the region of the laser spots.

 

Conclusions:

 

Interim results from this pilot study show that the application of 12 extremely low energy, non thermal, 2RT laser pulses to the mid-macula resulted in visual function improvements in the regions of greatest pre-treatment dysfunction. These regions are likely to be at greatest risk of developing late stage AMD, providing circumstantial evidence that the progress of AMD is being slowed or partially reversed by this laser treatment.

 

Clinical Trial:

 

http://www.anzctr.org.au (ACTRN12609001056280)

 

Keywords: age-related macular degeneration • laser