New technique to demonstrate the network of blood capillaries of the human retina in their three-dimensional arrangement.

A method is presented that demonstrates the whole network of the blood capillaries of the human retina, making it possible (using a dark-field microscope at high magnification) to view the three-dimensional arrangement of this network in different planes by moving the drive of the microscope. The basic principle includes filling the vascular system with oxygen in statu nascendi by injection of H2O2 into the vitreous body of the intact eye and achieving fixation of the retinal tissue by application of a mixture of H2O2 and ethanol, and rendering the dry and flat retinal preparation transparent by soaking it in a specially prepared resin. The retinal vessels are made visible in an optically empty dark field by diffraction of light in a gas-filled specimen. This method allows preparation of the human retinal vasculature in simply enucleated eyes without cannulation of the central retinal artery and, therefore, it may be appropriate to support pathological and anatomical investigations.