The contrast sensitivity function in low vision.
The contrast sensitivity of 51 low vision patients (95 eyes) showed a substantial decrease in all spatial frequencies. The peak contrast sensitivity was shifted to 1 C/D from the normal 3-4 C/D. The high-frequency cut off is correlated to the visual acuity positively. Of the 33 patients, the preferred eye was the eye with better peak sensitivity in 28 patients (84%), while the preferred eye was the eye with better visual acuity in 22 patients (66%). It seems that the peak sensitivity is more important than visual acuity in determining eye preference. It provides a useful information for the clinician to determine which eye to train with low vision aids. Forty patients among 46 patients (87%) with RFN (Recognized Frequency Number) > or = 3 are able to read No.5 reading card, while 5 patients among 5 patients with RFN < 3 are not able to read No.5 reading card. The contributions of CSF to the low vision are evaluated.
Jin
C J
CJ
Zhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou, China.
Wu
D Z
DZ
Wu
L
L
D000293:Adolescent; D000328:Adult; D000368:Aged; D001296:Audiovisual Aids; D002648:Child; D015350:Contrast Sensitivity; D006801:Humans; D008268:Macular Degeneration / Q000150:complications; D008875:Middle Aged; D009896:Optic Atrophy / Q000150:complications; D012174:Retinitis Pigmentosa / Q000150:complications; D015354:Vision, Low / Q000209:etiology / Q000503:physiopathology*; D014792:Visual Acuity