In comparatively numerous cases, we find on or upon the entrance of the optic nerve membranous or hypertrophic structures of a bluish-white color, which undoubtedly are not due to pathological changes. Up to the present time I have seen seven cases which presented this appearance: thus giving a proportion of about 1 to 1500 cases. If we consider the proportion of opaque nerve fibres on the optic nerve or in the retina as 1:600 (according to my journal), we see that, as regards frequency, the first-mentioned picture is not much rarer than the latter. It is, therefore, quite astonishing that the most commonly used text-books—excepting some foreign ones—make no mention whatever of the forms in question, whereas the so-called rabbit formation is quite extensively discussed.
A look at the past . . .. Arch Ophthalmol. 1999;117(2):249. doi:10.1001/archopht.117.2.249