[The assessment of blue mechanism by measuring the threshold versus intensity curve under flashed background]

The threshold versus intensity curve with brief blue stimuli with a flashing background of the same wavelength was measured in normal subjects and subjects with several kinds of optic nerve and retinal diseases. In young normal subjects the threshold curve rose sharply away from the line measured under the same conditions but without flashing blue background, as has been reported in measurements with light of long wavelengths. In the convalescent stage of optic neuritis, diabetic retinopathy, and central serous chorioretinopathy, the threshold curves presented two patterns; one pattern was shifted upward and the other shifted upward and to the right. We suggest that this method with short wavelength light is useful in differentiating retinal diseases from the change of optic media, and for layer-by-layer diagnosis of retinal diseases.