Outpatient Facility Coding Alert

Question: How do I code a bilateral frontal sinus balloon dilation and a left sphenoid sinus balloon dilation?

New Jersey Subscriber

Answer The coding mechanics behind this procedure are especially tricky when working with the new set of endoscopic sinus surgery codes. First, you’ll want to report 31298 (Nasal/sinus endoscopy, surgical; with dilation of frontal and sphenoid sinus ostia (eg, balloon dilation)) with modifier LT (Left Side).

Next, you will report 31296 (Nasal/sinus endoscopy, surgical; with dilation of frontal sinus ostium (eg, balloon dilation)) with modifiers RT (Right Side) and either XS (Separate Structure) or 59 (Distinct Procedural Service), depending on payer. For Medicare Part B, you’ll report modifier XS. For other commercial payers, report modifier 59.

The reporting of 31298-LT indicates to the payer that the provider performed a left-sided frontal sinus balloon dilation and a left-sided sphenoid sinus balloon dilation. Reporting 31296-RT-XS indicates to the payer that the provider performed a right-sided frontal sinus balloon dilation.

In checking the National Correct Coding Initiative (NCCI, or CCI) edits, you’ll find that NCCI bundles 31296 into 31298 using a modifier indicator of “1.” Since 31296 is the column 2 code, you will append the respective modifier (XS or 59) to 31296. For Medicare Part B patients, it is advised that you report modifier XS over 59 for greater specificity. Modifier XS informs the insurance company that the two surgeries should be unbundled due to the fact that the operations are performed on separately identifiable sites.

In this case, you are referring to the left- and right-sided frontal sinus balloon dilations.

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