Neurosurgery Coding Alert

You-re not alone if you find yourself questioning how to report intra-operative monitoring (IOM) services.

Neurosurgery coders in multispecialty clinics frequently see claims for intra-operative monitoring. Jo Helms, CPC, PCS, clinic coding specialist with Affinity Health Systems in Appleton, Wis., is just one of several readers who has requested guidance on how to report these services.

"Recently, one of our neurologists began performing IOM for spinal procedures, and we have many questions about these services," Helms writes. She suggests that coding for multiple EMG studies can be especially confusing.

Luckily, IOM claims are easy to handle if you remember the following four points.

1. Claim the Baseline Study

Prior to performing IOM, the monitoring physician may first conduct one or more studies to establish a patient's "baseline" responses. You should report these baseline studies separately from the IOM. CPT provides a list of approved baseline studies/primary procedures for use with IOM, which includes EMG, nerve conduction studies, evoked potentials and others.

You may report multiple baseline studies when necessary. For instance, if the monitoring physician performs both sensory evoked potentials (SEP) and an EMG baseline study, you may bill for both. However, under AMA/CPT rules, you should report the baseline electrophysiologic study only "once per operative session."

An important exception: When using EMG as a baseline study to test pedicle screws, you may report as many units as necessary of 95870 (Needle electro-myography; limited study of muscles in one extremity or non-limb [axial] muscles [unilateral or bilateral], other than thoracic paraspinals, cranial nerve supplied muscles or sphincters).

Explanation: "Code 95870 is used for limited study (fewer than five muscles) in one limb or non-limb (axial) muscles, other than thoracic paraspinal or cranial nerve," says Gloria Galloway, MD, FAAN, FABEM, professor with the Division of Neurology and director of the intra-operative monitoring program at Ohio State University Children's Hospital. "So, if you are only doing limbs, then the maximum is four units of 95870. If you add other non-limb muscles, however, you need to bill for those with additional units of 95870 as well."

For instance, Galloway says, "If three of the muscles the physician tests are on one limb, that is one unit of 95870. But if you tested two additional non-limb axial muscles in addition to four limbs [for instance, when testing from pedicle screw sites], you would code for six units of 95870."

Count muscles and limbs: If the monitoring physician tests five or more muscles from each limb, you would turn to EMG series 95860-95864 (Needle electromyography ...), depending on the number of limbs tested.

You should report IOM using +95920 (Intraoperative neurophysiology testing, per hour [list separately in addition to code for primary procedure]). For each hour of monitoring the physician provides, you may report one unit of 95920. You must report a minimum of 31 minutes of monitoring to bill for the next hour of service, as follows:

Monitoring time of -

30 minutes or less: Not reported separately

31-90 minutes: 95920 x 1

91-150 minutes: 95920 x 2

151-210 minutes: 95920 x 3.

When determining IOM time, you can't count "standby time" in the operating room or the time spent conducting any baseline studies. As a rule of thumb, you should begin counting IOM time immediately after the surgery begins.

Important: The operating surgeon should not claim IOM. Only a dedicated physician, with the sole task of monitoring the patient during the surgery, should separately claim IOM services.

You should always append modifier 26 (Professional component) to 95920, as well as any baseline study codes, when the monitoring physician provides these services in a facility setting. The monitoring physician will recover reimbursement for his time and effort, and the facility can collect separately for the use of its equipment.

The diagnoses you link to your IOM and baseline study codes should match the diagnoses that the surgeon uses to justify the primary surgical procedure.

Why? The reason the surgeon asks the neurologist to monitor the patient arises from the same problem that the surgeon wishes to correct. And because the IOM and baseline study are linked, they share the same diagnosis.

The neurosurgeon performs a single-level C6-C7 anterior cervical discectomy with anterior cervical fusion, anterior cervical instrumentation, and structural allograft bone graft for displacement of cervical disc without myelopathy (722.0). A neurologist provides IOM baseline studies, including needle EMG of four extremities and upper- and lower-limb motor evoked potentials. He monitors the patient throughout the surgery, from 4 p.m. to 6:15 p.m. For the surgeon, you would report:

For the monitoring neurologist, you would report:

Because the reason for the surgery was a displaced disc, you should link 722.0 to IOM and baseline studies in addition to the surgical codes.