**6. Patents**

An instrument implementing the algorithms for IVC delineation used in this paper was patented by Politecnico di Torino and Universitá di Torino (WO 2018/134726).

**Author Contributions:** Conceptualization, L.M., S.R., P.P. and M.P.; methodology, L.M.; software, L.M.; validation, L.M.; data preparation, P.P. and M.P.; investigation, L.M. and S.R.; writing–Original draft preparation, L.M.; writing–Review and editing, S.R., M.P., P.P.; visualization, L.M.; supervision, M.P. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was carried out as part of the project "Method and apparatus to characterise non-invasively images containing venous blood vessels", funded through the PoC Instrument initiative, implemented by LINKS, with the support of LIFFT, with funds from Campagnia di San Paolo.

**Conflicts of Interest:** The authors declare no conflict of interest.
