The invention relates to a device and a method, by which the intraocular pressure in a patient's eye is changed by artificially applying a variable stimulation pressure causing, upon reaching specific intraocular pressure values, the presence of characteristic measurement criteria in the retina of the eye, which allow global and local retinal blood pressure values to be derived from the intraocular pressure value. Based on the retinal blood pressure values, which are determined online or preferably offline, local retinal perfusion pressure values (rPP) can be computed and represented in an image of the retina as a pressure mapping image.