Radiology Coding Alert

Question: We have a patient who presents for a maxillofacial computerized tomography (CT) scan without contrast for a severe, chronic postnasal drip. The physician documents a possible nasal polyp during the imaging. We coded this as R09.8 and received a denial for medical necessity from the insurance company. Should we appeal?

Indiana Subscriber

Answer: Unfortunately, R09.82 (Postnasal drip) does not fall under the coding crosswalk for CPT® code 70486 (Computed tomography, maxillofacial area; without contrast material).

When considering whether another diagnosis is applicable, you should check the ICD-10 guidelines. The 2018 ICD-10 guidelines state: "Codes that describe symptoms and signs, as opposed to diagnoses, are acceptable for reporting purposes when a related definitive diagnosis has not been established (confirmed) by the provider."

In this example, a definitive diagnosis has not been established, so you should not resubmit with a different diagnosis, such as J33.9 (Nasal polyp, unspecified). If, after checking your local coverage determinations (LCDs) and confirming with the payer that the diagnosis code is not eligible for payment, you may consider an appeal since the claim was denied for medical necessity.

In your justification for the appeal, you should state that the patient presented for imaging due to chronic, underlying symptoms of postnasal drip, with the final diagnosis being inconclusive of any definitive disease. You may include information that explains how CT scan imaging is vital in identifying diseases and disorders of the nasal cavity and sinuses. You should also consider including a handwritten note from the provider explaining the medical necessity behind the procedure.

Medicare defines medically necessary services as "healthcare services or supplies needed to prevent, diagnose, or treat an illness, injury, condition, disease, or its symptoms and that meet accepted standards of medicine." Therefore, if you are able to justify the CT scan as a medically necessary component in treating and diagnosing the underlying cause of the patient's postnasal drip, you may be able to heighten your chances of getting the appeal overturned.