G418 – Routine EEG - professional component (16 - 21 channel EEG)
OHIP Diagnostic & Therapeutic Procedures Code — DIAGNOSTIC AND THERAPEUTIC PROCEDURES · Schedule of Benefits
This service is the professional component for a routine Electroencephalogram (EEG) that uses 16 to 21 channels. A routine EEG is defined on page as consisting of at least a twenty-minute recording with referential and bipolar montages and at least eight channels (except in neonates). The procedure should include hyperventilation and photic stimulation in all cases where clinically possible.
When to Use
- Use G418 when performing a standard diagnostic EEG requiring 16 to 21 channels, specifically when the recording duration meets the 20-minute minimum threshold.
- Select G418 over G415 when the technical complexity of the study necessitates the higher channel count (16-21) to ensure adequate diagnostic coverage.
- Use this code for routine studies where hyperventilation and photic stimulation are successfully completed, distinguishing it from studies that fail to meet these procedural requirements.
Common Pitfalls
- Billing G418 alongside any sleep study codes (e.g., J898, J899) will result in an automatic rejection, as these services are mutually exclusive.
- Failure to explicitly document the use of 16-21 channels creates an audit risk, as the Ministry may default the claim to the lower-paying G415 if the channel count is not clearly stated.
- Submitting G418 on the same day as G415, G543, or G496 is prohibited; only one of these professional component codes is eligible for payment per patient per day.
Billing Tips
- Ensure your reporting software automatically appends the channel count to the clinical note to satisfy the documentation requirements for G418 versus G415.
- If you perform a G496 or G543 that fails to meet their specific technical requirements, you may be downgraded to the G418 fee; ensure your documentation supports the 16-21 channel minimum to secure this payment.
Effective: April 1, 2025
J. Diagnostic and Therapeutic Procedures
DIAGNOSTIC AND THERAPEUTIC PROCEDURES
Diagnostic
Diagnostic and Therapeutic Procedures
The EEG recording must be at least twenty minutes long.
Recording must include referential and bipolar montages.
Hyperventilation and photic stimulation should be performed where clinically possible.
The use of 16 to 21 channels must be documented to differentiate from G415.
1. The amount payable for a sleep-deprived/induced EEG, or an EEG with time-locked video recording that does not meet the above requirements will be reduced to that for a routine EEG fees (i.e. G414 and G415/G418).
2. G414 is not eligible for payment with G541.
3. Only one of G415, G418, G543 or G496 are eligible for payment per day.
4. EEG services (i.e. G414, G415, G418, G496, G541, G543, G540, G545, G542, G546, G554, G555, or G544) are not eligible for payment with any overnight or daytime sleep study (i.e. J898, J899, J990, J896, J897, J895, J890, J889, J893 or J894).
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