It has been several years since CMS released the X modifier series, are you using these correctly or not at all? In an end of year survey, published in Part B News, 78% of respondents said they had reported an X modifier in 2019. The creation of the X modifier series is to report with greater specificity the scenarios when just 59 had been used in the past. Effective July 1, 2019, MAC’s now process modifier 59 when used on either column 1 or 2 codes in addition to the most appropriate X series modifier.nnHere is a great scenario for the use of XU [Unusual non-overlapping service]:nnIf a peripheral nerve block injection is performed for postoperative pain management on the same date as the anesthesia code used for the procedure, the use of modifiers XU is appended to the peripheral nerve block injection to indicate that it was used for the postoperative pain management.nnFor other great scenarios directly from CMS, click here. It has great detailed information about these modifiers and some additional scenarios to help.nnAnother great article on this topic was released in the December 30th issue of Part B News by Jim Dresbach, click here to read!