[Idiovariation of papillogenesis]

Among the great number of idiovariations of papillogenesis, some malformations near the optic disk are of special interest with regard to their formal origin, morphology and differential diagnosis. This matter is discussed on the basis of the author's own observations, which relate to the coloboma spurium of the optic disk, to the ectatic colobomas situated on the disk, the circumscribed pitting of the disk and to Handmann's optic nerve anomaly. With regard to the central retinal changes which occur in coloboma spurium of the disk and in circumscribed pitting of the disk, these are not to be explained by mechanical factors, but as correlation alterations. They are also closely connected with the macular changes in Handmann's optic nerve anomaly. Coloboma spurium of the disk as well as circumscribed pitting of the disk should be distinguished. With regard to their formal origin and morphology, the former malformation should be designated major pitting and the latter minor pitting of the disk. A guide is given to the differential diagnosis of major and minor pitting of the disk, as well as of glaucomatous cupping.