G40.814 — Lennox-Gastaut syndrome, intractable, without status epilepticus
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- Medical records must be maintained and available upon request, be legible, include complete patient identification and dates of service, and contain the legible signature of the physician or non‑physician practitioner responsible for care.
- The submitted medical record must support the selected ICD‑10‑CM diagnosis code(s) and the CPT/HCPCS code billed must accurately describe the service performed.
- When FDG PET is performed in the context of a CMS‑approved practical clinical trial using a specific protocol, the claim should be reported with modifier Q0.
- When only the technical or professional component is performed, report the PET procedure with modifier TC (technical) or 26 (professional), respectively.
Key Coverage Criteria
- FDG PET (CPT 78608 / HCPCS A9552) is covered to differentiate Alzheimer's disease (AD) from frontotemporal dementia (FTD) in patients with a recent dementia diagnosis who have documented cognitive decline for at least 6 months and who meet diagnostic criteria for both AD and FTD.
- FDG PET is covered for patients with mild cognitive impairment (MCI) or early dementia only when performed as part of a CMS‑approved practical clinical trial (coverage with evidence development).
- FDG PET (CPT 78608) is covered for intractable seizures only when used as part of a pre‑surgical evaluation for seizure focus localization.
- Ambulatory EEG is covered for diagnostic evaluation when seeking to detect clinical seizures or interictal epileptiform activity.
- Ambulatory EEG is covered for pre-surgical evaluation to localize seizure onset when capture of multiple seizures is needed for surgical planning.
- Ambulatory EEG is covered for routine follow-up monitoring of known seizure disorder or previously identified epileptiform activity.
20 Active Policies
L39995 — Pharmacogenomic Testing
J06
L33399 — EEG Ambulatory Monitoring
J06
A57030 — Billing and Coding: EEG Ambulatory Monitoring
J06
A59914 — Billing and Coding: Pharmacogenomic Testing
J06
A59915 — Billing and Coding: Pharmacogenomic Testing
Related Codes
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