Dr Theuns graduated in 1987 from the university of Gent. He has worked in  private practices from 1987 till 2023 (Bergen op Zoom from 1987-1992, Papendrecht from 1992-2023, Soesterberg from 2003- 2020) Amstelveen 2010-2015, Wageningen 2018-present, Leusden 2023-present