G821 – OCT unilateral or bilateral - active management of retinal disease with laser or intravitreal injections
OHIP Diagnostic & Therapeutic Procedures Code — DIAGNOSTIC AND THERAPEUTIC PROCEDURES · Schedule of Benefits
Unilateral or bilateral Optical Coherence Tomography (G821) is designated for the active management of retinal disease with laser or intravitreal injections. The performing or supervising physician must also interpret the results. This service is limited to patients aged 18 and older. As per general Optical Coherence Tomography (OCT) guidelines, it is only insured when the ophthalmologist is the most responsible physician for the patient's retinal disease and/or glaucoma, and is not payable if performed for cataract surgery preparation.
When to Use
- Use G821 when performing OCT to monitor treatment response for patients receiving ongoing anti-VEGF intravitreal injections for conditions like wet AMD or diabetic macular edema.
- Use G821 for patients undergoing active retinal laser therapy where the OCT is required to guide or evaluate the efficacy of the laser intervention.
Common Pitfalls
- Billing G821 for routine pre-operative OCT scans for cataract surgery is strictly prohibited and will result in recovery upon audit.
- Submitting G821 for patients under 18 years of age will trigger an automatic rejection; use appropriate pediatric-specific codes if applicable.
- Billing G821 when the OCT is performed for diagnostic screening rather than active management of a retinal disease or glaucoma will lead to claim rejection.
Billing Tips
- Ensure your documentation explicitly links the OCT findings to the active management plan (e.g., decision to proceed with or defer an injection) to justify the medical necessity of G821.
- Monitor your annual volume of G818, G820, and G821, as G822 only becomes payable once the combined limit of these codes is exhausted.
Effective: April 1, 2025
J. Diagnostic and Therapeutic Procedures
DIAGNOSTIC AND THERAPEUTIC PROCEDURES
Diagnostic
Diagnostic and Therapeutic Procedures
Patient must be 18 years of age or older.
Payment rules: 1. Except as described in payment rule #2, OCT is an insured service only: a. for the diagnosis and management of retinal disease and/or glaucoma; and b. when the ophthalmologist performing the service is the physician most responsible for the care of the patient's retinal disease and/or glaucoma. 2. Any OCT service rendered in whole or in part for preparation related to cataract surgery is not eligible for payment.
Payment rules: 1. G822 is limited to a maximum of 8 services per patient per 12 month period and a maximum of 16 services per patient for 24 consecutive months. 2. G822 is only eligible for payment when the limit of any combination of G818, G820 or G821 is reached.
Payment rules: 1. G823 is limited to a maximum of 12 services per 12 month period. 2. G818, G820, G821 and G822 are not eligible for payment when rendered on a patient younger than 18 years of age.
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