Replacing the Amsler grid: a new method for monitoring patients with age-related macular degeneration.
OBJECTIVE
To investigate a method that uses hyperacuity, the Macular Computerized Psychophysical Test (MCPT), to evaluate the central macular visual field in patients with age-related macular degeneration (AMD).


METHODS
Prospective case-control study of a diagnostic test.


METHODS
One hundred eight eyes of 108 Patients with AMD and 51 eyes of 51 age-matched patients with no retinal disease. Patients with AMD included 32 (30%) patients with choroidal neovascularization (CNV), 23 (21%) with geographic atrophy (GA), 35 (32%) with AMD with high-risk characteristics (HRC), and 18 (17%) with early AMD with non-HRC.


METHODS
Each subject underwent the MCPT, in which a virtual line composed of dots (white dots on a black background, maximal contrast) is flashed across different macular loci to a perifoveal radius of 7 degrees. Patients' responses were recorded and automatically analyzed using a specific algorithm developed before the onset of the study. All patients also underwent a supervised Amsler grid examination on the encounter before or after the MCPT in random order.


METHODS
Distortion, scotoma, or blurring perceived by the patient after a swift change of fixation was considered positive on the MCPT. Any perception of distortion, scotoma, or blurring was considered positive on the Amsler grid.


RESULTS
Of the 32 patients with CNV, 30 (94%) were found positive on the MCPT and 11 (34%) were found positive on the Amsler grid. Of the 23 GA patients, 21 (91%) were found positive on the MCPT and 7 (30%) were found positive on the Amsler grid. Of the 35 HRC patients, 28 (80%) were found positive on the MCPT and 3 (9%) were found positive on the Amsler grid, and of the 18 early AMD with non-HRC patients, 8 (44%) were found positive on the MCPT and 3 (17%) were found positive on the Amsler grid. Of the 51 controls, 3 (6%) were positive on the MCPT and 1 (2%) was positive on the Amsler grid.


CONCLUSIONS
The MCPT was superior to the Amsler grid in detecting AMD-related lesions in this cohort. Studies are underway to determine whether the MCPT is feasible for home monitoring to provide early detection of progression to CNV.
Department of Ophthalmology, Tel-Aviv Medical Center, Tel-Aviv, Israel.
Anat
A
Loewenstein
Rafael
R
Malach
Michaela
M
Goldstein
Igal
I
Leibovitch
Adiel
A
Barak
Eli
E
Baruch
Yair
Y
Alster
Omer
O
Rafaeli
Isaac
I
Avni
Yuval
Y
Yassur
D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D020256:Choroidal Neovascularization / Q000175:diagnosis; D005189:False Positive Reactions; D005260:Female; D015799:Gyrate Atrophy / Q000175:diagnosis; D006801:Humans; D008268:Macular Degeneration / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D010469:Perceptual Distortion; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012607:Scotoma / Q000175:diagnosis; D012680:Sensitivity and Specificity; D014786:Vision Disorders / Q000175:diagnosis*; D014787:Vision Tests / Q000295:instrumentation / Q000379:methods*; D014794:Visual Fields