Neurosurgery Coding Alert

Question: For a patient diagnosed with left frontal basilar extra-axial tumor, our surgeon did the following procedures:

The operative note reads as follows:

"After infiltration of the scalp, a bicoronal scalp incision was made behind the hairline. It was on the level of the zygomatic arch on the left and just above the zygomatic arch on the right. This was taken down through subcutaneous tissues and galea as well as pericranium in the midline. We went through galea sparing temporalis muscle out to the right and left. The tissue was sharply divided allowing us to progressively reflect the bicoronal scalp flap anteriorly. Pericranium was reflected with the scalp flap in the midline down to the supraorbital rims. The scalp was covered with moist gauze and held up with fish hooks....

The microscope was brought into use. With elevation of the frontal love, we identified her tumor adherent to the falx. There were generous vessels over the surface, which were cauterized. We cut through a well-formed outer capsule and identified soft, predominately tan-colored fluid. This was mildly vascular. Portions of this were sent to pathology for review. On quick section, the tumor was most suggestive of a meningioma. The tumor was clearly extra-axial in location.

We then used the ultrasonic aspiration to debulk a portion of the tumor. Capsule was reflected from the left towards the midline. We were able to place Cottonoid pledgets progressively over the medial frontal love and separate this from the tumor. We did identify intermittent draining veins but also been parasitized arterioles. These were cauterized and divided. We identified the falcine attachment inferiorly. We used bipolar cautery to cauterize through falx above the tumor attachment. Falx was divided. We then cauterized the falx down to the crista galli. The tumor extended right down to the crista galli. We removed dura and the inferior basilar attachment of the tumor. A small amount of tumor extending into the right anterior cranial fossa was removed. The tumor was debulked allowing us to further remove tumor down towards the basal attachment. The left olfactory bulb was identified. Tumor was found just above this. We removed dura on either side of the crista galli. With a small rongeur, we removed the tip of the crista galli process to remove any possible bony origin. In doing so, we entered an ethmoid sinus. We cauterized some of the mucosa here and packed this very small opening with bacitracin-soaked Gelfoam as well.

At this point the tumor was removed in its entirety. Both olfactory nerves and bulbs appeared to be intact. It was clear that covering the frontal sinus and the anterior cranial fossa flow with a pericranial graft would be beneficial to secure healing. As such, gauze was removed from the scalp flap. We cut a pericranial graft approximately 6 to 7 cm along the frontal base. It was perhaps 6 to 7 cm in length as well. This was turned down over the frontal sinus. We used 4-0 Vicryl to tack pericranium onto dura of the anterior cranial fossa floor to the left and right of the left and right olfactory nerves. Another simple taking suture was placed in the posterior margin of some residual falcine/dural prominence....."

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Answer: This procedure is best described with 61512 (Craniectomy, trephination, bone flap craniotomy for excision of meningioma, supratentorial). In general, skull base codes are not reported if a craniotomy code specific to the procedure exists. If there is documentation for a skull base approach, then one would pair the appropriate approach code for the location of the neoplasm (anterior vs. middle fossa, intradural vs. extradural) with the definitive resection code of the same anatomical site.

The craniotomy performed in this example did not include descriptions of osteotomy, rhinotomy, ethmoidectomy, or sphenoidectomy that are considered parts of an anterior skull base approach. Microdissection is documented and can be separately reported with the add-on code +69990 (Microsurgical techniques, requiring use of operating microscope [List separately in addition to code for primary procedure]) for the microsurgical dissection. The locally-harvested pericranial graft is considered a bundled service.

Editor's note: To read the full operative note for this procedure, email the editor, Tarveen Jandoo, MD at tarveenj@codinginstitute.com .