Abstract
Purpose:
The principal target of this pilot study was to correlate the different stages of Age-Related Macular Degeneration (AMD) according to the simplified classification of the Age Related Eye Disease Study Group (AREDS), such correlation is based on new evaluation criteria using a microperimetry system aiming for a larger scale evaluation of this instrument as a screening test.
Methods:
A complete eye examination and a microperimetry MAIA TM (Macular Integrity Assessment, Ellex, Centervue, Padova, Italy) examination was performed on 59 eyes with early, intermediate or advanced AMD. We analysed 27 evaluation criteria for every pathology group stage.
Results:
The mean average was 74 years-old (min: 54, max: 87); 20 female and 12 male participants, the average visual acuity was 71.6 letters (SD ± 17.8 letters). Thirteen eyes (22%) were classified as stage 1, 11 eyes (18.6%) as stage 2, 17 eyes (28.8%) as stage 3, and 18 eyes (30.6%) as stage 4. All the mircoperimetry criteria tested related to the retinal sensitivity were found to have a statistically significant difference among the stages (p<0.05). Fixation stability was unstable on 55.6% of the eyes classified as stage 4 (p=0.001). The analysis of the distance among the 2 PRLs (preferred retinal locus) was considerable big for the stage 4 (p<0.05). The mean sensitivity in stages 2 and 3 was correlated to the presence or not of reticular pseudodrusen (p<0.05).
Conclusions:
The mean sensitivity and the categorized sensitivity (set to 25 dB, 15 dB and 5 dB), the 5 higher and lower stimuli sensitivity appeared to be the most sensible criteria to differentiate the AMD stages. Poor fixation stability, was particularly correlated to low visual acuities and frequently found in cases of advanced AMD notoriously atrophic. Microperimetry is a new reproducible method of anatomical-functional macular analysis, which a promising future.
Keywords: 412 age-related macular degeneration •
642 perimetry •
754 visual acuity