T65.821D — Toxic effect of harmful algae and algae toxins, accidental (unintentional), subsequent encounter
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 record documentation must demonstrate clinical evidence of an intracranial disorder or documentation of an established intracranial disease to support coverage of cranial CT.
- When contrast-enhanced CT is ordered for staging, documentation must record the known primary cancer (e.g., lung cancer, breast cancer, lymphoma) and clinical rationale for brain staging.
- When contrast is used to assess perfusion, lesion characterization, blood–brain barrier defects, or neovascularity, the clinical indication for contrast administration should be documented.
Key Coverage Criteria
- Cranial CT (with or without contrast) is covered when the patient has clinical evidence of an intracranial disorder or an established intracranial disorder/disease.
- Contrast-enhanced CT is reasonable and necessary to assess cerebral perfusion, for example in suspected or known cerebrovascular accident (CVA).
- Contrast-enhanced CT is covered to characterize a specific intracranial lesion.
- Contrast-enhanced CT is covered to detect blood–brain barrier defects such as infarcts, tumors, infection, or vasculitis.
- Contrast-enhanced CT is covered to detect neovascularity associated with intracranial tumors.
- Contrast-enhanced CT is covered for staging when there is known primary lung cancer, breast cancer, or lymphoma that are likely to metastasize early to the brain.
2 Active Policies
A56612 — Billing and Coding: CT of the Head
L34417 — CT of the Head
Related Codes
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