Neurology & Pain Management Coding Alert

Simplify your NCS claims with this advice from the experts

Multiple nerve conduction studies (NCS) are a common tool of neurologists, especially in diagnosing conditions such as carpal tunnel syndrome (354.0). Unfortunately, payers often misunderstand these tests and will partially reimburse or may deny them altogether.

The American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) in Rochester, Minn., offers tips for correctly coding this procedure when you-re using 95900 (Nerve conduction, amplitude and latency/velocity study, each nerve; motor, without F-wave study), 95903 (... motor, with F-wave study) and 95904 (... sensory).

1. One Nerve, One Charge -- and Maybe Modifier 59 

When you-re using 95900, you can't bill for different segments of the same nerve. One nerve equals only one charge.

Try using modifier 59 (Distinct procedural service) when you report 95900 with 95903 or 95904.

Tip: The modifier indicates a distinct procedure, so, technically, you shouldn't have to report it with the procedure code. Including it, however, sometimes helps your claim go through more easily.

2. Distinguish Details Between Codes

Don't bill 95900 and 95903 together on the same nerve on the same day, because one is for an F-wave study and the other is without an F-wave study. On the other hand, you can use 95900 and 95903 for different nerves on the same day because they then describe two distinct procedures provided on the same day.

Again, that's where modifier 59 can help.

Neurologists report that carriers frequently deny payment when the physician bills 95900 and 95903 for the same patient in the same visit. These codes have been subject to a Correct Coding Initiative (CCI) -edit- that is designed to detect unbundling or splitting of CPT codes, such as reporting separate codes for related services that are supposed to be covered by one comprehensive code.

The government is attempting to detect unbundling for 95900 and 95903 billed to the same nerve. Nonetheless, you can bill 95900 and 95903 to the same patient on the same day when the physician tests multiple nerves (some with and some without F-wave studies), says Neil Busis, MD, chief of the division of neurology and director of the neurodiagnostic laboratory at the University of Pittsburgh Medical Center in Shadyside.

3. Beware of Modifier 51  

Modifier 51 (Multiple procedures) is not appropriate when reporting nerve conduction studies performed on multiple nerves (95900-95904). Although some carriers have insisted that you append modifier 51 to these procedure codes if your neurologist tested multiple nerves on the same day, this is incorrect coding. The AMA concurs with the AANEM on this issue.

Here's why: Relative values for these codes were deliberately set low to reflect that physicians usually perform these procedures multiple times on a patient during a single examination. The physician work and supplies involved in performing multiple nerve conduction studies are multiples of those involved in a single nerve conduction study.

There are no economies of scale involved in giving multiple tests to a patient in one setting. If your carrier erroneously tells you to append these codes with the lower-paying modifier 51, insist that this is incorrect coding and include documentation from the AMA on this issue.

4. Observe Reasonable Testing Limits 

Each nerve constitutes one service unit, according to CPT's Appendix J. The appendix outlines -a reasonable maximum number of studies- (per diagnostic category) that a neurologist usually performs to diagnose most patients. Although the physician determines the actual number of studies performed, the chart lists four or fewer nerve
conduction studies for most types of studies. Some examples include:

- Carpal tunnel syndrome (354.0), unilateral: three motor and four sensory studies

- Radiculitis (729.2): three motor and two sensory

- Mononeuritis (355.9): three of each

- Myopathy (359.9): two of each

- Polyneuropathy (357.x): four of each.

Exception: These limits don't apply if the patient requires evaluation for a second diagnosis the same year. There may be cases where the patient needs additional testing. If so, include documentation in the patient's chart that shows the medical necessity for more tests. Carriers expect that repeat testing won't be necessary in 80 percent of cases. Be sure to include comparisons with the previous test results in the documentation.