Functional imaging of the human papilla and peripapillary region based on flicker-induced reflectance changes.

A non-invasive functional imaging technique of the nervous tissue of the human eye fundus based on two wavelength light reflectance changes (DeltaR %) is presented. The effect of 30 degrees diffuse luminance flicker field made of two spectral components (569 and 600 nm) on DeltaR was studied in six normal volunteers. Group averaged DeltaR was significant and similar in all quadrants of the optic disc at 569 nm with a mean equal to -10.7% for the tissue of the optic disc and -3.6% for the peripapillary regions. At 600 nm, the DeltaR were also significant but smaller, i.e. -3.5% for the disc tissue and -1.7% for the peripapillary region. The changes at 569 and 600 nm represent most probably blood volume changes. The 600 nm reflectance did not show evident features suggesting the presence of flicker-induced oxygenation changes.