Neurosurgery Coding Alert

Learn the difference between “pallidotomy” and “thalamotomy.”

When reporting stereotactic surgery procedures, you can feel lost in the plethora of possible codes. However, you can navigate your way to the most specific code and ensure you earn your most deserved payment by focusing on two key elements:

• Anatomical site
• Physician’s intention, as described by key terms.

Confirm Site of Stereotactic Lesions

For stereotactic lesions in the globus pallidus or thalamus, you report code 61720 (Creation of lesion by stereotactic method, including burr hole[s] and localizing and recording techniques, single or multiple stages; globus pallidus or thalamus).

Get to know the anatomy: Globus pallidus is a structure in the brain that regulates voluntary movements in the body. Thalamus is a symmetrical midline structure in the brain. It acts as a switchboard or relay station for various sensory and motor signals to the higher centers in the brain. The thalamus also regulates sleep and alertness. “The thalamus is a complicated subcortical structure that serves as a relay station for a variety of motor and sensory inputs. Consequently, it can be a source of movement disorders or pain syndromes,” says Gregory Przybylski, MD, director of neurosurgery, New Jersey Neuroscience Institute, JFK Medical Center, Edison.

Highlight the Reason for Lesions

Your surgeon may create a lesion in the globus pallidus to control some abnormal involuntary muscle tremors. If you are able to locate the term “pallidotomy” in the operative note, you can be assured that your surgeon created a lesion in the globus pallidus. “The frequency of destructive procedures for movement disorders has declined with the increasing understanding and effectiveness of deep brain stimulation,” says Przybylski.

When you are able to locate the term “thalamotomy” in the operative note, you confirm that your surgeon made a lesion in the thalamus. Your surgeon may do this to treat a pain syndrome.

If your surgeon studied the radiological impressions of the thalamic lesions by using CT scan, you should be able to locate the same in the operative note.

Example: Your surgeon may typically describe the CT appearance of a thalamic lesion having as a discrete central core of increased attenuation surrounded by an area of decreased attenuation.

When you learn that your surgeon worked on other brain structures that are anatomically located below the cerebral cortex but not the globus pallidus or thalamus, you report code 61735 (Creation of lesion by stereotactic method, including burr hole[s] and localizing and recording techniques, single or multiple stages; subcortical structure[s] other than globus pallidus or thalamus). You report 61735 for stereotactic lesions in structures like the hippocampus, amygdala, corpus callosum, cerebellum, and basal ganglia.

Note: Codes 61720 and 61735 are inclusive of the burr holes created to facilitate the approach to the central structures and also the localization and recording techniques. “In addition, as these are considered stereotactic procedures, the placement of a frame, i.e. CPT® 20660 (Application of cranial tongs, caliper, or stereotactic frame, including removal [separate procedure]), if performed for frame-based procedures, as well as the use of neurological navigation, i.e. CPT® 61781 ((Stereotactic computer-assisted [navigational] procedure; cranial, intradural [List separately in addition to code for primary procedure]) are both considered bundled services,” says Przybylski.

Ascertain What Your Surgeon Does

When you read that your surgeon attempted a stereotactic procedure, you make it to the right code only when you confirm what precisely the intent of the procedure was.

If your surgeon does a stereotactic biopsy, you report code 61750 (Stereotactic biopsy, aspiration, or excision, including burr hole[s], for intracranial lesion).

Also, check if your surgeon used any radiographical assistance for the biopsy. If yes, you turn to code 61751 (Stereotactic biopsy, aspiration, or excision, including burr hole[s], for intracranial lesion; with computed tomography and/or magnetic resonance guidance).

Example: You may read that your surgeon used a burr hole approach to aspirate a colloid cyst in the third ventricle. In this case, you should report 61750. However, you would code 61751 if your surgeon did the same with MRI guidance. “However, if neuroendoscopy was used in the approach to performing the aspiration, you may consider using 62162, depending on the manner with which the cyst is ultimately treated,” says Przybylski.

Similarly, you would report 61760 (Stereotactic implantation of depth electrodes into the cerebrum for long-term seizure monitoring) when your surgeon implants electrodes in the brain for mapping the location of seizures. You should choose 61770 (Stereotactic localization, including burr hole[s], with insertion of catheter[s] or probe[s] for placement of radiation source) when your surgeon attempts stereotactic localization and placing a probe or catheter for the delivery of the radioactive seeds. Your surgeon may work with a radiation oncologist implanting the seeds.

Note: The code 61760 is inclusive of electrode removal, if your surgeon does one. In an event that the wires are loosened after the electrodes are placed, your surgeon may document that on the following day, the patient was taken back to the operating room “where I moved the electrodes and patched the burr hole.” In this case, you report 61760 for the original electrode placement. CPT® doesn’t include a code specifically for removal of this type of electrode because 61760 is inclusive of the eventual removal. Therefore, removal on the following day is considered part of the original procedure and not separately coded. “This is similar to other procedures in which a temporary hardware or device is placed (e.g. Halo, ventriculostomy) and the procedure is valued for the subsequent removal of the device as well,” says Przybylski.

Report Navigation with Add-On Codes

Codes +61781 (Stereotactic computer-assisted [navigational] procedure; cranial, intradural [List separately in addition to code for primary procedure]), +61782 (… cranial, extradural [List separately in addition to code for primary procedure]), and +61783 (… spinal [List separately in addition to code for primary procedure]) are add-on codes. The navigation codes (+61781, +61782, +61783) should be listed immediately after the primary code for which the navigation system was used.

Example: You can bill +61781 with 61510 (Craniectomy, trephination, bone flap craniotomy; for excision of brain tumor, supratentorial, except meningioma), as well as other craniectomy codes for tumor, cyst and abscess. “The surgeon should dictate the preparation, image review and target planning to support use of the navigation code when it is not considered a bundled service,” says Przybylski.

Anatomy Is Important In 61790 And 61791

The only difference you can spot in the descriptors of codes 61790 (Creation of lesion by stereotactic method, percutaneous, by neurolytic agent [e.g., alcohol, thermal, electrical, radiofrequency]; gasserian ganglion) and 61791 (… trigeminal medullary tract) is that 61790 refers to gasserion ganglion and 61791 refers to the medullary tract. “The former procedure is more commonly done as a method to manage trigeminal neuralgia,” says Przybylski.

Remember: Gasserian ganglion is also called the trigeminal or semilunar ganglion. Your surgeon will approach the trigeminal nucleus through the foramen ovale. So you can look for this approach in the operative note and confirm that 61790 is the right code you can report. For brainstem lesions, you report 61791.

Note: You’ll typically report 350.1 (Trigeminal neuralgia) as a diagnosis for either 61790 or 61791.

Radiosurgery: Keep a Count on Lesions

You report code 61796 (Stereotactic radiosurgery [particle beam, gamma ray, or linear accelerator]; 1 simple cranial lesion) or 61798 (… 1 complex cranial lesion) depending upon the simple or complex lesion your surgeon created. “Given the differences in physician work between planning and treating a simple, smaller and/or uniform lesion compared with an irregular, larger, and more dangerously-located lesion, the former single radiosurgery code descriptor was revised to account for the differences in work and complexity a number of years ago,” says Przybylski.

Simple vs complex: Complex lesions include those that are adjacent (5 mm or less) to the optic nerve/optic chasm/optic tract or within the brain stem. Certain types of lesions are inherently considered complex. These include schwannomas, arterio-venous malformations, pituitary tumors, glomus tumors, pineal region tumors, and cavernous sinus/parasellar/petroclival tumors. Simple cranial lesions are less than 3.5 cm in maximum dimension that do not meet the CPT® definition of a complex lesion.

If the surgeon treats multiple lesions, you’ll add either +61797 (Stereotactic radiosurgery [particle beam, gamma ray, or linear accelerator]; each additional cranial lesion, simple [List separately in addition to code for primary procedure]) or +61799 (… each additional cranial lesion, complex [List separately in addition to code for primary procedure]) to your claim, based on whether the lesions are simple or complex. You can include either of these add-on codes for a maximum of five lesions treated during the session.

Do Not Overlook the Head Frame

Linear accelerator based radiation is frameless. Many other treatment systems, however, are frame-based - which means you’ll add another code to your claim. If your surgeon uses a frame-based system, be sure to include +61800 (Application of stereotactic head frame for stereotactic radiosurgery [List separately in addition to code for primary procedure]) on your claim, says Marianne Schipper, CPC, a spine, brain, and endovascular coding specialist at Barrow Neurosurgical Associates in Phoenix, Ariz. Sometimes the neurosurgeon applies the frame but doesn’t participate in the rest of the radiosurgery procedure, says Deborah Messinger, CPC, a coding specialist with Massachusetts General Physicians Organization in Charlestown. In that case, you report 20660 (Application of cranial tongs, caliper, or stereotactic frame, including removal [separate procedure]) instead of +61800.