H70.91 — Unspecified mastoiditis, right ear
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- 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.
- Providers should check and apply Correct Coding Initiative (CCI) edits and applicable LCD guidance for correct code combinations before billing.
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.
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- G83.0 | Diplegia of upper limbs
- H44.19 | Other endophthalmitis
- H44.532 | Leucocoria, left eye
4 Active Policies
A57215 — Billing and Coding: MRI and CT Scans of the Head and Neck
A57204 — Billing and Coding: MRI and CT Scans of the Head and Neck
L35175 — MRI and CT Scans of the Head and Neck
L37373 — MRI and CT Scans of the Head and Neck
Related Codes
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