Ray Painter, MD
I removed two stones from the right kidney through the ureter in the ambulatory surgery center. First, I removed a small stone from the lower pole of the right kidney using manipulation and then a basket. Then I performed a lithotripsy on a larger stone located in the upper calyx. My billing department says I cannot charge for removal of both stones. I think I read in one of your articles that you could charge for both. Who is correct? If I can charge for both, how should I code?
As you know, the rules for coding multiple stones have changed over the years. We have tried to keep you posted with each new rule and the intended implementation. Unfortunately, the changes have created some confusion as to what to do because published articles have provided conflicting information as the changes require different approaches with each new rule.
In your case, both stones were in the same organ (structure).
For Medicare, we will need to refer to the National Correct Coding Initiative rules for guidance. First, we will look at the rules for Units of Service as they are listed in Chapter 7 of the NCCI manual to find the following:
“The unit of service (UOS) for a procedure describing destruction or removal of renal system calculus(i) is one (1). The UOS is not each calculus. If a procedure for destruction or removal of renal system calculi is performed bilaterally, the CPT code may be reported with modifier 50 and one (1) UOS.”
Thus, coding the removal of each stone with the same procedure is clearly not allowed.
To address the issue of using two separate procedures to remove the stones, we look further for clarification of the use of anatomic procedure-to-procedure (PTP) edit modifiers and find the following:
“Most NCCI PTP edits for codes describing procedures that may be performed on bilateral organs or structures (e.g., arms, eyes, kidneys, lungs) allow use of NCCI-associated modifiers (modifier indicator of “1”) because the two codes of the code pair edit may be reported if the two procedures are performed on contralateral organs or structures. Most of these code pairs should not be reported with NCCI-associated modifiers when the corresponding procedures are performed on the ipsilateral organ or structure unless there is a specific coding rationale to bypass the edit. The existence of the NCCI PTP edit indicates that the two codes generally should not be reported together unless the two corresponding procedures are performed at two separate patient encounters or two separate anatomic sites. However, if the corresponding procedures are performed at the same patient encounter and in contiguous structures, NCCI-associated modifiers should generally not be utilized.”
This section leaves a little room for interpretation; however, the general sentiment of the rule is that the use of two separate procedures on the same side and in the same organ should generally not be reported for the same encounter. The one caveat allowed, “unless there is a specific coding rationale to bypass the edit,” would be difficult to support. Therefore, we are going to agree with your compliance department for Medicare when it comes to reporting the treatment of the two stones with two separate codes if they are bundled within NCCI.