Z350 – Endoscopic sphenoidotomy - unilateral
OHIP Psychiatric Code — RESPIRATORY SURGICAL PROCEDURES · Schedule of Benefits
Endoscopic sphenoidotomy - unilateral is a surgical procedure to create an opening into the sphenoid sinus on one side using an endoscopic approach. This is classified as an Independent Operative Procedure (IOP) as indicated by the 'Z' prefix. As per the surgical preamble on page , specific rules apply to billing assessments with IOPs. A bilateral procedure can be claimed using the add-on code E843A. If a 3D CT/MRI image-guided system is used under specific circumstances, add-on code E845A is also payable.
When to Use
- Use Z350 for a primary endoscopic sphenoidotomy performed on one side, ensuring it is not bundled into a more comprehensive sinus procedure.
- Use Z350 in conjunction with E843A when the procedure is performed bilaterally, as Z350 is strictly defined as a unilateral service.
Common Pitfalls
- Billing E845A without explicit documentation of the specific anatomical distortion or critical structure proximity required by the billing rules.
- Attempting to claim Z350 alongside other endoscopic sinus procedures without applying the 85% payment adjustment rule for secondary procedures.
- Assuming E845A is payable for all image-guided surgeries; it is strictly restricted to the specific clinical scenarios listed in the code description.
Billing Tips
- Always document the specific anatomical distortion or the proximity to critical structures (e.g., carotid artery, optic nerve) in the operative report to support the E845A claim during potential audits.
- When performing multiple sinus procedures, identify the major procedure to claim at 100% and apply the 85% reduction to Z350 if it is the secondary procedure.
Effective: April 1, 2025
P. Respiratory Surgical Procedures
RESPIRATORY SURGICAL PROCEDURES
Surgical
Respiratory Surgical Procedures
Note: E845A is only eligible for payment under the following circumstances: 1. Identification of the anatomy of the paranasal sinuses distorted by previous surgery, trauma, abnormalities of development or benign or malignant tumours; or 2. A pathological lesion abuts the base of the skull, orbit, optic nerve or carotid artery.
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