All codes
M050
M050 – Frontal sinusotomy, extended, Draf II, unilateral
OHIP Ophthalmology Code · Schedule of Benefits
Frontal sinusotomy, extended, Draf II, unilateral (endoscopic approach)
When to Use
- Use M050 when performing an extended endoscopic frontal sinusotomy (Draf II) involving the removal of the frontal beak and agger nasi cells to provide wide drainage of the frontal sinus.
- Select M050 over Z318 when the procedure requires more extensive resection of the frontal sinus floor than a simple Draf I approach.
- Use M050 when the surgical intent is to address chronic frontal sinusitis that has failed medical management and requires wider access than a standard endoscopic approach.
Common Pitfalls
- Billing M050 alongside M052 is a common error; M052 (Draf III) is a more extensive procedure and typically encompasses the work of M050, leading to potential audit flags for unbundling.
- Failing to document the specific anatomical extent of the frontal sinusotomy can lead to claims being downgraded to Z318 during a post-payment audit.
- Attempting to claim E845 without explicit documentation of the specific anatomical distortion or proximity to critical structures (skull base, orbit, carotid) as required by the code's eligibility rules.
Billing Tips
- Always append E865 when performing the procedure bilaterally, as M050 is strictly defined as a unilateral service.
- Ensure the operative report explicitly describes the resection of the frontal sinus floor and the agger nasi to justify the Draf II classification over the less extensive Z318.
Provider Fee$350.00
Anaesthetist Fee$159.60
Non-Anaesthetist Fee$159.60
Effective: April 1, 2026
Service Type
Respiratory Surgical Procedures
Code Classes
Surgery
The procedure must be documented in an operative report.
M050 is an endoscopic approach to the frontal sinus (Draf II).
Major pre-operative visit is not included in the surgical fee and should be claimed separately.
Multiple procedures: Full benefit for the major procedure and 85% for others performed under the same anaesthesia or within 14 days for the same condition.
Ready to bill this code?
SnapBill makes OHIP billing simple — auto-filled codes, validation, and batch submission.