Among the most frequent and characteristic types of defects of the field of vision is the so-called defect in the bundle of nerve fibers which arises as a consequence of the course of the nerve fibers across the retina. From the nasal half of the papilla they extend radially, whereas from the upper and lower edge they extend in large curves above and below the macula.
The upper and lower bundles of nerve fibers meet in the temporal part of the retina. The horizontal meridian is a rectilinear "raphe" which from the macula extends quite out to the temporal meridian of the retina (fig. 1). If, now, such a bundle is injured, for example, at the edge of the papilla, a defect will appear corresponding to the whole section of the retina which is served by the respective bundle, and the defect will therefore have the form of the projection