Neurosurgery Coding Alert

Removal, retrieval, and replacement of flap codes are as essential as primary procedure codes.

Cranial bone grafts may appear complex to code. The only way to a good claim is to code for all steps of the procedure. Remember, you not only code for placement and completion of the graft procedure, you also code for the retrieval of the graft. Here is guidance to stepwise approach to cranial bone grafting.

Consider this example: You may read that your surgeon did an emergent decompressive frontoparietal craniectomy in a patient with intracranial subdural haemorrhage and subfalcine herniation and cerebral brain swelling. Further, your surgeon may have subsequently done a left frontoparietal cranioplasty after retrieving the cranial bone graft that was placed in a subcutaneous pocket in the abdomen.

In the box below is a stepwise guide to coding these services.

Primary Procedure is Key

The first step is to report the primary procedure that your surgeon does to address the diagnosed condition in the patient. In the example above, you would report code 61312 (Craniectomy or craniotomy for evacuation of hematoma, supratentorial; extradural or subdural) as the primary procedure because your surgeon is doing a decompressive craniectomy in a patient with a subdural hematoma. “Although there are specific codes for decompressive craniectomy (CPT^® 61322 and 61323), these are reported when the decompressive craniectomy is performed without intra or extraparenchymal hematoma evacuation,” Przybylski says.

Earn for Bone Grafting and Reconstruction Procedures

In the example, your surgeon places the bone graft in a subcutaneous pocket in the abdomen. You use the add-on code +61316 (Incision and subcutaneous placement of cranial bone graft [List separately in addition to code for primary procedure]) to describe temporary placement of a cranial bone graft into a distant subcutaneous site for future retrieval.

Note: Since +61316 is an add-on code, you always report it with a code for the primary procedure. Some of the primary procedure codes may include codes like 61304 (Craniectomy or craniotomy, exploratory; supratentorial) - 61571 (Craniectomy or craniotomy; with treatment of penetrating wound of brain), and 61680 (Surgery of intracranial arteriovenous malformation; supratentorial, simple) - 61705 (Surgery of aneurysm, vascular malformation or carotid-cavernous fistula; by intracranial and cervical occlusion of carotid artery).

When reporting +61316, you do not need a multiple procedure modifier. “Remember, when applying add-on codes such as 61316, modifier 51 for multiple procedures does not apply because add-on codes are only valued for the incremental work performed beyond that of the primary procedure,” Przybylski says.

Rule out freeze-dried flaps: You report +61316 only when your surgeon documents the temporary placement of the cranial bone flap in the subcutaneous pocket for safe storage. You do not report this code if the flap was freeze-dried. You have no specific code for reporting the freeze-drying of the flap. “Only the subcutaneous placement of a bone flap is reportable because there is separately identifiable physician work in creating and closing the subcutaneous flap,” Przybylski says.

You should next report the retrieval of the cranial bone graft from the subcutaneous site. Your surgeon accesses the subcutaneous pocket in the abdomen and removes it from there. For this service, you use code +62148 (Incision and retrieval of subcutaneous cranial bone graft for cranioplasty [List separately in addition to code for primary procedure]). This code includes the repair of the subcutaneous site. The code, +62148, is used instead of a code for creating an artificial cranioplasty for the bony defect.

Note: You do not separately report for repair of this temporary placement site.

Finally, you report the bone flap replacement using code 62143 (Replacement of bone flap or prosthetic plate of skull).

Check if Modifiers Apply

Check the operative note and confirm the global period of the initial procedure, which is typically 90 days. If the retrieval of the cranial bone graft from the temporary abdominal subcutaneous pocket and replacement of the flap is within the 90-day global period of the initial procedure, you append modifier 58 (Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period) to the appropriate cranial repair code and retrieval code.

So, in the example above, you will report 62143-58 and 62148-58.

However, you do not need to append any modifiers to the codes 61312 or +61316. Since the craniotomy and subcutaneous bone flap placement are the original procedures performed and given that the subcutaneous bone flap placement is an add-on code exempt from modifier 51, there are no modifiers applicable to either code 61312 or +61316. “It is recommended that, in the operative documentation of the initial procedure, your physician dictates the plan for future bone flap retrieval and replacement once the acute intracranial swelling has resolved,” Przybylski says.