Symposium on glaucoma: joint meeting with the National Society for the Prevention of Blindness. New observations on the radial peripapillary capillaries.

I n his monograph on the retinal circulation, Michaelson noted that a layer of radially arranged capillaries, which he termed radial peripapillary capillaries (RPCs), occupied the superficial retina at the posterior pole in man. Toussaint, Kuwabara, and Cogan, and Francois and Neetens also mention briefly this group of vessels, the former noting that these capillaries had a double Bjerrum arclike configuration (Fig. 1). Recently, similar radially arranged, superficially located retinal capillaries have been described in the monkey, cat, and pig (Figs. 2 and 3). In all these species, as well as in man, the RPCs have certain features which distinguish them from other retinal capillaries (Fig. 4): (1) they pursue relatively long straight paths, (2) they rarely anastomose with each other, and (3) they lie in among