2023 Coding Tips: Functional Endoscopic Sinus Surgery

Functional endoscopic sinus surgery (FESS) is a common area of confusion for many coders. Even though the sinus is a small anatomical region, there are several code choices available for FESS. Understanding the anatomy, as well as the techniques and guidelines for FESS, will set a coder up for success in coding these cases.

Sinus Anatomy

There are four sinuses: ethmoid, sphenoid, frontal, and maxillary. ICD-10-CM and CPT selections depend on which of the sinuses are treated, whether one or multiple sinuses are treated, and the techniques used by the performing surgeon.

Sinusitis Diagnoses

Let’s review FESS diagnosis codes. FESS is performed to treat sinusitis, most often chronic sinusitis. It’s important to read the documentation closely to make accurate ICD-10-CM selections based on the sinus(es) involved.

If only one sinus is involved, choose the specific code from the following:

• J32.0 — Chronic maxillary sinusitis
• J32.1 — Chronic frontal sinusitis
• J32.2 — Chronic ethmoidal sinusitis
• J32.3 — Chronic sphenoidal sinusitis

If 2-3 sinuses are involved, code:

• J32.8 — Other chronic sinusitis

If all four sinuses are involved, code:

• J32.4 — Chronic pansinusitis

If the documentation doesn’t specify which sinus(es) are involved, code:

• J32.9 Chronic sinusitis, unspecified

CPT Codes

Procedure code selection will be determined by the sinus(es) treated as well as the technique used (opening of sinus, removal of tissue, balloon dilation). If more than one method is used on the sinus, it’s important to watch NCCI edits closely to determine which code to report. Note: All the sinus codes below include diagnostic nasal endoscopy (31231) as well as nasal/sinus endoscopy with biopsy, polypectomy, or debridement (31237).

Sinus Dilation

The codes for dilation of the sinuses are selected based on which sinus is treated. Make sure you watch for the combination codes to be used when both the frontal and sphenoid sinuses are dilated. There is no combination code for the maxillary sinus.

For sinus dilation, choose from the following codes:

• 31295 Nasal/sinus endoscopy, surgical, with dilation (eg, balloon dilation); maxillary sinus ostium, transnasal or via canine fossa
• 31296 Nasal/sinus endoscopy, surgical, with dilation (eg, balloon dilation); frontal sinus ostium
• 31297 Nasal/sinus endoscopy, surgical, with dilation (eg, balloon dilation); sphenoid sinus ostium
• 31298 Nasal/sinus endoscopy, surgical, with dilation (eg, balloon dilation); frontal and sphenoid sinus ostia

FESS

Similar to the dilation codes, traditional FESS codes are selected based on the sinus but also the extent of the procedure. Coders need to watch for tissue removal (not just suctioning of fluid/mucus) in each sinus treated and understand the guidelines regarding the combination codes.

Starting with the ethmoids, there are five different CPT options, depending on the extent of the ethmoidectomy (partial vs total) and if other sinuses were treated. It’s important to note that if only a partial ethmoidectomy is performed, a combination CPT for another sinus would not be used.

For FESS, choose from the following codes:

• 31254 Nasal/sinus endoscopy, surgical with ethmoidectomy; partial (anterior)
• 31255 Nasal/sinus endoscopy, surgical with ethmoidectomy; total (anterior and posterior)
• 31253 Nasal/sinus endoscopy, surgical with ethmoidectomy; total (anterior and posterior), including frontal sinus exploration, with removal of tissue from frontal sinus, when performed
• 31257 Nasal/sinus endoscopy, surgical with ethmoidectomy; total (anterior and posterior), including sphenoidotomy
• 31259 Nasal/sinus endoscopy, surgical with ethmoidectomy; total (anterior and posterior), including sphenoidotomy, with removal of tissue from the sphenoid sinus

According to the American Medical Association, only one ethmoid CPT would be reported per side, per encounter. If a total ethmoidectomy is performed in conjunction with a sphenoidotomy and a frontal sinus exploration, the coder would report either 31257 or 31259 (depending on if tissue is removed from the sphenoid sinus or not) with 31276 for the frontal sinus. It would not be appropriate to report both 31253 and 31257 (or 31259) in the same encounter.

If the sphenoid sinus is not treated during the same encounter, but a total ethmoidectomy is performed with a frontal sinusotomy, then 31253 would be reported.

There are no combination codes involving the maxillary sinus. Code selection depends on if tissue is removed or not:

• 31256 Nasal/sinus endoscopy, surgical, with maxillary antrostomy;
• 31267 Nasal/sinus endoscopy, surgical, with maxillary antrostomy; with removal of tissue from maxillary sinus

If the frontal sinus is treated, there is only one CPT option, regardless of if tissue is removed or not:

• 31276 Nasal/sinus endoscopy, surgical, with frontal sinus exploration, including removal of tissue from frontal sinus, when performed

Similar to the maxillary sinus, there are two CPT selections for the sphenoid sinus (when performed without a total ethmoidectomy) that are based on tissue removal:

• 31287 Nasal/sinus endoscopy, surgical, with sphenoidotomy;
• 31288 Nasal/sinus endoscopy, surgical, with sphenoidotomy; with removal of tissue from the sphenoid sinus

Coding Scenarios

Applying the codes from above can still be a challenge for coders when multiple sinuses are involved. Let’s look at four common scenarios.

1. All four sinuses are treated with partial ethmoidectomy
   • Report 31254, 31256 or 31267 (depending on tissue removal), 31276, and 31287 or 31288 (depending on tissue removal).
2. All four sinuses are treated with total ethmoidectomy
   • Report 31257 or 31259 (depending on tissue removal), 31256 or 31267 (depending on tissue removal), and 31276.
3. Total ethmoidectomy is performed with frontal sinusotomy and maxillary antrostomy
   • Report 31253 and 31256 or 31267 (depending on tissue removal).
4. If any sinuses are treated without total ethmoidectomy, report the appropriate CPTs based on tissue removal and sinus treated.

Navigation and Implants

If computer navigation is used, some commercial payers may separately reimburse for this CPT code:

• 61782 — Stereotactic computer-assisted (navigational) procedure; cranial, extradural (List separately in addition to code for primary procedure)

Coders should also watch for implants to be placed in the sinuses, such as Propel or Sinuva, and report them appropriately using the following:

• S1091 — Stent, noncoronary, temporary, with delivery system (Propel)
• J7402 — Mometasone furoate sinus implant, (Sinuva), 10 mcg