Coding Endoscopic Sinus Surgery: Per Sinus, Per Side
Functional endoscopic sinus surgery is one of the few operations coded anatomically piece by piece: each sinus, on each side, has its own code. That structure rewards precise documentation and punishes vague notes.
The per-sinus structure
- 31255 — ethmoidectomy, total (anterior and posterior)
- 31256 / 31267 — maxillary antrostomy, without / with tissue removal
- 31276 — frontal sinus exploration
- 31287 / 31288 — sphenoidotomy, without / with tissue removal
Each is unilateral: append -50 (or RT/LT per payer preference) when both sides were done. The operative note should state, for every sinus, what was opened and whether tissue was removed — that single sentence is often the difference between 31256 and the higher-valued 31267.
What bundles
Diagnostic nasal endoscopy is included in surgical endoscopy of the same side. Septoplasty performed for access and turbinate work have specific NCCI pairings — an inferior turbinate procedure alongside septoplasty needs documentation that it was a distinct, indicated service, not incidental.
Navigation and image guidance
Computer-assisted navigation is an add-on that requires documented use — a line in the note stating the system was registered and used for intraoperative localization.
Clinical Capture builds the sinus-by-sinus code list directly from what the note describes, applies laterality, and flags the bundling pairs — so a four-sinus bilateral case is captured fully and defensibly.
This article is educational and not coding, billing, or legal advice. Always verify codes and values against the current CPT®, ICD-10-CM, and CMS Physician Fee Schedule, follow NCCI edits and payer policy, and confirm with a certified coder before submitting a claim. Document only work that was actually performed.