The relationship between scotoma displacement and preferred retinal loci in low-vision patients with age-related macular degeneration.
OBJECTIVE
Adaptive strategies in low-vision patients with age-related macular degeneration use preferred retinal loci (PRLs) for the purpose of achieving better visual function. In the process of redirecting the eye toward the PRL, central scotomata are displaced eccentrically. The consequential effect of the first on the second may offer an indirect method for PRL identification. The purpose of this study was to clarify the relationship between scotoma displacement and PRL location.


METHODS
Prospective, nonrandomized, observational case series.


METHODS
Forty-one adults with a confirmed diagnosis of age-related macular degeneration.


METHODS
Scotoma characteristics were obtained with automated perimetry. PRL topography was obtained with the Nidek MP-1 instrument. Outcome measures selected for this study were scotoma displacement and PRL eccentricities estimates.


RESULTS
We tested 16 males and 25 females aged 70-98 years (mean 82.5 [SD 6.71] years) with best-corrected visual acuity of 0.81 (SD 0.24) logMar units (20/128). PRL location logically matched scotoma displacement in 30 study subjects (73.17%, p < 0.00432). In this subgroup (n = 30), PRL eccentricity (5.55 [SD 3.35] degrees ) was almost identical to scotoma displacement eccentricity (5.22 [SD 1.98] degrees )(p < 0.65).


CONCLUSIONS
Scotoma displacement recorded with macular perimetry methods offers reasonable indirect estimates of PRL location.
Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada. snm1@rogers.com
Samuel N
SN
Markowitz
Natalya
N
Aleykina
D000221:Adaptation, Ocular; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008268:Macular Degeneration / Q000150:complications*; D008297:Male; D011446:Prospective Studies; D012160:Retina / Q000503:physiopathology*; D012607:Scotoma / Q000209:etiology* / Q000503:physiopathology*; D015354:Vision, Low / Q000209:etiology* / Q000503:physiopathology*; D014792:Visual Acuity; D058609:Visual Field Tests / Q000379:methods