If you actually wear your dosimeter during the treatment, this does matter and the dosimeter needs to be turned in and the treatment reported (ask at the badging office for the damaged dosimeter form).
If you have had treatment and are coming to SLAC to work, please let us know if the treatment is within the past 3 days.
Most nuclear medicine diagnostic procedures are using short half-life (few hours) isotopes (eg. Tc-99m, F-18, etc..) so it is safe to wear dosimeter after 3 days (i.e. there won't be a false positive reading on your dosimeter).
During this ~3 day period in which the isotopes are decaying, we may have to ask that you do not perform any radiological work or enter RCAs because we cannot accurately monitor your occupational dose.