**9. Diagnosis**

Typical forms of SS are easily diagnosed by means of criteria of Su and Liu published in 1986 (Su & Liu, 1986) (table 4). Von den Driesch provided a more evolved modification of these criteria in 1994 (von den Driesch, 1994) (table 5), but it has had less acceptation. As we previously indicated, there are patients with "atypical" SS, transitional forms of SS and other ND, as well as cases in which it is only possible to set a generic diagnosis of ND.
