They are both hereditary vitreous diseases that give you an optically empty vitreous. Jansen’s disease, however, has a high incidence of retinal detachment while Wagner’s does not. Other causes of optically empty vitreous include Stickler Syndrome and Goldman-Favre.
There is no difference, apart from the nationality of the studied pedigrees: Wagner’s being Swiss, Jansen being Dutch. Both pedigrees have the same gene defect (Versican) The Swiss pedigree was studied in 1938, Jansen’s in 1962. When later on researchers studied the original pedigree again, they also found retinal detachments.
