SUMMARY
The contrast sensitivity of 20 diabetic patients with 20/20 of visual acuity and 45 controls was measured with low contrast acuity charts. Four contrast levels were used (91, 55, 29 e 5%).
Multifactorial analysis of variance (contrast vs clinical group) showed that the interaction between the mainfactors was significant. The two groups differed for high contrast optotypes but the difference was greater for low contrast. The results indicated that optotypes can be useful for characterizing low spatial frequency channels.