A81.9 — Atypical virus infection of central nervous system, unspecified
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- This article provides billing/coding guidelines that complement Local Coverage Determination L34417 for CT of the head; consult LCD L34417 for specific coverage, coding, and documentation requirements.
- Medical records must include history and physical notes, laboratory results, and documentation of signs and symptoms that warrant the head/neck diagnostic imaging.
- Accurate HCPCS/CPT coding must be submitted to differentiate CT and MRI scans from other radiology services and to support coverage determinations.
- Documentation and supporting information must be available to Medicare upon request.
Key Coverage Criteria
- CT or MRI scans of the head or neck are covered when the medical record documents the scan is reasonable and necessary for diagnostic evaluation.
- Coverage requires documentation supporting clinical indication such as history and physical exam findings, laboratory results, and signs or symptoms that justify the diagnostic test.
- G71.21 | Nemaline myopathy
- G83.0 | Diplegia of upper limbs
- H44.19 | Other endophthalmitis
- H44.532 | Leucocoria, left eye
7 Active Policies
A57215 — Billing and Coding: MRI and CT Scans of the Head and Neck
AETNA-CPB-0221 — Quantitative EEG (Brain Mapping)
A56612 — Billing and Coding: CT of the Head
A57204 — Billing and Coding: MRI and CT Scans of the Head and Neck
L34417 — CT of the Head
Related Codes
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