The reduction of the number of the small RET+ neurons in the left -axotomized- OM could be due either to the RET downregulation or to the increase of the volume of these neurons (Gersh and Bodian, 1943; Gutmann, 1964; Deitch and Rubel, 1989) making them exceed the limit of Ø = 20 μm and get counted as large RET+ ones. Here, RET is linked to ocular melanoma.