G31.9 — Degenerative disease of nervous system, unspecified
ICD-10-CM
Prior Authorization
No Prior Auth Required
No active coverage policies found for this code (low 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.
- Speech-language pathology (SLP) services for treatment or evaluation of communication disorders when determined reasonable and necessary per LCD L35070.
- Selection and prescription of speech-generating devices should be billed with CPT code 92607.
- Adaptation and training for speech-generating devices should be billed with CPT code 92609.
20 Active Policies
A56937 — Billing and Coding: Psychiatry and Psychology Services
J06
L33632 — Psychiatry and Psychology Services
J06
A59049 — Billing and Coding: NCD Coding Article for Positron Emission Tomography (PET) Scans Used for Non-Oncologic Conditions
J09
L35070 — Speech - Language Pathology (SLP) Services: Communication Disorders
J12
Related Codes
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