Filling-in phenomenon in patients with age-related macular degeneration: differences regarding uni- or bilaterality of central scotoma.
OBJECTIVE
The purpose of this study was to explore the presence of the filling-in phenomenon in patients with uni- or bilateral central scotoma (CS) resulting from natural history or laser photocoagulation of choroidal neovascularization in age-related macular degeneration (AMD).


METHODS
Sixteen consecutive patients with unilateral CS and 14 patients with bilateral CS were assessed (44 eyes) with a scanning laser ophthalmoscope (SLO). Scotoma was delineated by scotometry with a point (1 degree x1 degree) moving radially from the periphery to the center of the lesion. In addition, patients underwent a line test, consisting of a horizontal line moving vertically and a vertical line moving horizontally, from the periphery to the center. The lines were longer than the macular lesion and were projected onto the retina. Patients were asked to indicate when the lines seemed interrupted. The perceptual filling-in phenomenon was considered to be present when limits of the perceived scotoma, determined by the line test, were smaller than those assessed by scotometry. In patients with bilateral CS, the results were analyzed to distinguish the less or more severely affected eye.


RESULTS
In all eyes, the limits of the scotoma obtained with the scotometry test corresponded to the anatomic edges of the macular lesion. In patients with bilateral CS, the filling-in phenomenon was observed in 12 out of 14 (85%) less severely affected eyes, but only in one (7%) of their more severely affected eyes. In patients with unilateral CS, the phenomenon was observed in only one out of 16 (6%) eyes.


CONCLUSIONS
These results suggest that the filling-in phenomenon mostly occurs in patients with bilateral central scotoma, and almost always in their less affected eye. Thus, it did usually not occur in an eye if the fellow eye was better.
Cohen
Salomon Yves
SY
INSERM U 483, Laboratoire de Biophysique de la Vision, 10 Avenue de Verdun, 75010 Paris, France.
Lamarque
Frédéric
F
Saucet
Jeanne-Claude
JC
Provent
Pierre
P
Langram
Cecilia
C
LeGargasson
Jean-François
JF
D000368:Aged; D000369:Aged, 80 and over; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D006801:Humans; D017075:Laser Coagulation; D007834:Lasers; D008268:Macular Degeneration / Q000150:complications / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009887:Ophthalmoscopy; D010466:Perceptual Closure / Q000502:physiology*; D012607:Scotoma / Q000209:etiology / Q000503:physiopathology*