Retinal Vascular Micrometry and Essential Hypertension

Variations in the diameters of retinal vessels observable ophthalmoscopically in the eyes of normal and of hypertensive persons have drawn the attention of numerous workers since the first report of retinitis in nephritis was published by von Graefe,¹in 1855 ; however, Liebreich,²in 1859, in his detailed description of "albuminuric retinitis," was the first to mention the existence of narrowed arterial vessels. Frequent attempts have been made since the initial published method by Ruete,³in 1852, to obtain absolute measurements of the delineable ophthalmoscopically visible retinal structures in the living human eye (table 1). The basic goal has been the attainment of unquestionable accuracy by practical means. Numerous ingenious instruments and methods have been devised, all of which, however, in some manner combine a grid, graticule or micrometer scale with an ophthalmoscopic apparatus. The application of retinal photography, as advocated by Tengroth⁴and by Nordenson,⁵