a method of measuring blood pressure in the blood vessels of the retina. The method involves ophthalmoscopic examination of the pulse of the central retinal artery or vein during a gradual increase in intraocular pressure, which is artificially induced by compressing the eyeball with an ophthalmodynamometer; this instrument was invented in 1917 by the French ophthalmologist P. Baillard. An ophthalmodynamometer consists of a rod with a blunt thickening at the end for compressing the eye and a graduated scale in the form of a disk with two indicators; the rod is connected to a coil spring that transmits the extent of the eye compression to the scale. The diastolic and systolic pressures in the central retinal artery of man are determined by compressing the eye with a force of 30–35 g and 70–75 g, respectively. Ophthalmodynamometry is a useful diagnostic tool in ophthalmology, neuropathology, and internal medicine.