Abstract
Purpose: :
To determine the sensitivity of the blue cone system by static perimetry in patients with acute zonal occult outer retinopathy (AZOOR).
Methods: :
Five eyes of 4 patients with AZOOR, ages 16 to 30 years, were studied. Diagnosis of the AZOOR was based on clinical findings including an enlarged blind spot without corresponding ophthalmoscopic changes of the ocular fundus and with depressed multifocal electoretinograms. The visual sensitivity and mean deviations (MD) were measured by white–on–white (W/W) and blue–on–yellow (B/Y) automated perimetry.
Results: :
W/W perimetry showed that the average MD was –6.00 ± 1.87 (average±standard deviation) in the affected eyes and –1.14 ± 1.51 dB in the unaffected eyes leading to a difference of 4.87 ± 1.51 dB between the affected and unaffected eyes. B/Y perimetry, showed that the averaged MD was decreased to –16.65 ± 4.11 dB in the affected eyes and –3.00 ± 0.82 in the unaffected eyes leading to a difference of 13.65 ± 4.19 dB. The difference in the MD between the affected and unaffected eyes was significantly greater with B/Y perimetry than with W/W perimetry (P = 0.01, two–tailed Student’s paired t–test). In a case of a 19–year–old woman, the MD of B/Y perimetry did not change during the follow–up periods, while the MD of W/W perimetry recovered from –9.15 to –2.02 dB in 6 months after the onset.
Conclusions: :
Our results suggest that the decrease of blue cone sensitivity is diffusely present over the retina in eyes with AZOOR. We recommend B/Y perimetry as a sensitive measure to detect retinal dysfunction that is not detected by W/W perimetry. Blue cones may be more affected that other types of cones in this retinal disease.
Keywords: electrophysiology: clinical • visual impairment: neuro-ophthalmological disease • visual fields