Clarification please. The description of CPT 11960 is "insertion of tissue expander(s)". The (s) usually means single or multiple expanders would still only bill the code once. However, the MUEs for this code is 2 which implies 1 or 2 can be billed. Which is correct? If my physician is placing 2 expanders in 2 different sites (different incisions) on same day, would I bill 11960, 2 units or can I only bill 11960 once?