Billing code
M083A — Ethmoidectomy/antrostomy - Intranasal Ethmoidectomy Including Maxillary Antrostomy, With Endoscope Unilateral (not Eligible For Payment With M061 Or M054)
Endoscopic ethmoidectomy, one side
Bill M083 for endoscopic intranasal ethmoidectomy on one side, which may include maxillary antrostomy; add E844 when both sides are done.
Watch for: Not payable with M054 or M061, and an ethmoidectomy done only for surgical access isn't paid separately.
| Provider | Specialist | Assistant | Anaesthetist | Non-anaesthetist |
|---|---|---|---|---|
| $350.00 | $0.00 | $0.00 | $159.60 | $159.60 |
- Code
- M083A
- Description
- Ethmoidectomy/antrostomy - Intranasal Ethmoidectomy Including Maxillary Antrostomy, With Endoscope Unilateral (not Eligible For Payment With M061 Or M054)
- FHO+ basket
- Not in the FHO+ base rate basket (Schedule 2 or 2B).
- Effective date
- Apr 1, 2026
- Termination date
- No end date
Explanation
Updated October 26, 2026
Endoscopic intranasal ethmoidectomy, which may include maxillary antrostomy, one side. Add E844 for the other side.
What it covers
M083 is intranasal ethmoidectomy with an endoscope, which may include maxillary antrostomy, unilateral (P6).
When both sides are done, add E844 (P6).
Billing rules
- Not payable with M061 or M054 (P6).
- Payable with M050 or M052 only when the ethmoidectomy is medically needed to treat ethmoid sinus disease; ethmoidectomy done only for surgical access is not paid separately (P6).
- Add E845 for 3D CT/MRI image guidance only when anatomy is distorted (previous surgery, trauma, development, tumour) or the lesion abuts the skull base, orbit, optic nerve or carotid (P6).
- More than one procedure under the same anaesthetic: 100% for the major procedure and 85% for the others, including bilateral procedures, unless the Schedule says otherwise (SP2).
- Surgical procedures on children under 16 get the age premium (10–30% by age) (GP64).
Often billed with
- E844 bilateral procedure (P6).
- E845 image-guided system, when criteria are met (P6).
- M050 frontal sinusotomy or Z350 sphenoidotomy, when medically needed (P6).
Common rejections
- ADH: OHIP describes this as 'Cannot be billed together': M083 with M054 or M061 (P6).
Related codes: E844, M054, M050, Z350, E845, M052
Source: Schedule of Benefits (July 1, 2026), Respiratory Surgical Procedures, Accessory Nasal Sinuses, page P6.
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