R398 – Medial transnasal canthopexy - unilateral
OHIP Radiology Code — MUSCULOSKELETAL SYSTEM SURGICAL PROCEDURES · Schedule of Benefits
Medial transnasal canthopexy, unilateral, is a surgical procedure to correct the position of the medial canthus. An associated code, E557A, may be added when this procedure is performed in conjunction with another main operation. This is a surgical procedure with specific unit calculations for assistant (suffix B) and anaesthetist (suffix C) services. The anaesthetist fee is calculated using 6 base units plus time units.
When to Use
- Use R398 for a standalone unilateral medial transnasal canthopexy procedure performed to correct medial canthal dystopia or laxity.
- Use R398 in combination with E557 when the canthopexy is performed as a secondary or adjunctive procedure during a more extensive orbital or facial reconstruction.
Common Pitfalls
- Billing R398 bilaterally by using the code twice without appropriate modifiers or documentation, as this code is explicitly defined as unilateral.
- Failing to document the Injury Severity Score (ISS) in the medical record when attempting to claim the E420 trauma premium alongside R398.
- Attempting to claim E557 as a standalone code; it is strictly an add-on fee that must be submitted on the same claim as the primary surgical procedure.
Billing Tips
- Ensure the anaesthetist fee is calculated using the mandatory 6 base units plus the specific time units for the duration of the procedure.
- Verify that the E557 add-on is only applied when the canthopexy is secondary to a distinct primary surgical operation performed in the same operative session.
Effective: April 1, 2025
N. Musculoskeletal System Surgical Procedures
MUSCULOSKELETAL SYSTEM SURGICAL PROCEDURES
Surgical
Musculoskeletal System Surgical Procedures
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