Key facts for NCD 160.8
- Benefit category
- Diagnostic Tests (other), Physicians' Services
- Effective date
- 06/19/2006
- Implemented 06/19/2006
- Transmittal
- Transmittal 48
- Versions published
- 2
- Manual chapter
- 160
- NCD Manual (Pub. 100-03)
TL;DR
NCD 160.8 sets Medicare's national policy for electroencephalographic monitoring during surgical procedures involving the cerebral vasculature under the benefit category "Diagnostic Tests (other), Physicians' Services", effective 06/19/2006 and implemented 06/19/2006. Electroencephalographic (EEG) monitoring is a safe and reliable technique for the assessment of gross cerebral blood flow during general anesthesia and is covered under Medicare. Very characteristic changes in the EEG occur when cerebral perfusion is… It has been revised 1 time since publication and binds every Medicare Administrative Contractor nationally.
Indications and limitations of coverage
CIM 35-57
Electroencephalographic (EEG) monitoring is a safe and reliable technique for the assessment of gross cerebral blood flow during general anesthesia and is covered under Medicare. Very characteristic changes in the EEG occur when cerebral perfusion is inadequate for cerebral function. EEG monitoring as an indirect measure of cerebral perfusion requires the expertise of an electroencephalographer, a neurologist trained in EEG, or an advanced EEG technician for its proper interpretation.
The EEG monitoring may be covered routinely in carotid endarterectomies and in other neurological procedures where cerebral perfusion could be reduced. Such other procedures might include aneurysm surgery where hypotensive anesthesia is used or other cerebral vascular procedures where cerebral blood flow may be interrupted.
Text reproduced from the CMS Medicare Coverage Database record for NCD 160.8 version 2. View the original on cms.gov.
Revision history
03/2006 - Effective/Implementation Date: 06/19/2006. ( TN 48 ) (CR4278)
How this NCD shows up on remittances
A service denied under a National Coverage Determination returns CARC 50 (not deemed medically necessary) with remark N386 (decision based on an NCD); a denial citing a local policy instead carries N115. Because NCDs bind nationally, the appeal path is documentation that the patient meets the indications above, not a contractor-policy argument.
How QuickIntell applies NCD 160.8
QuickAuth checks the ordered service and diagnosis against NCD and LCD criteria before the encounter, QuickCode validates the diagnosis pairing on the claim, and QuickRCM routes CARC 50 denials with the policy text and the covered-code list attached so the appeal starts with evidence.
Frequently asked questions — NCD 160.8
What does NCD 160.8 cover?
Electroencephalographic (EEG) monitoring is a safe and reliable technique for the assessment of gross cerebral blood flow during general anesthesia and is covered under Medicare. Very characteristic changes in the EEG occur when cerebral perfusion is inadequate for cerebral function. EEG monitoring as an indirect measure of cerebral perfusion requires the expertise of an electroencephalographer, a neurologist… The full indications and limitations are reproduced on this page from the CMS Medicare Coverage Database.
When did NCD 160.8 take effect?
The current version (2) is effective 06/19/2006, implemented 06/19/2006, published in transmittal 48. CMS lists 2 versions of this NCD.
Does a Local Coverage Determination override NCD 160.8?
No. A National Coverage Determination binds all Medicare Administrative Contractors; an LCD can only address services or circumstances the NCD leaves open. Claims denied under this NCD typically return CARC 50 with remark N386 (NCD) rather than N115 (LCD).
Sources
Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-02. Verify against the primary file before billing or contracting decisions.
- Medicare Coverage Database NCDs via the CMS Coverage APIVersion API snapshot 2026-09-27 · effective 2026-09-20 · file national-coverage-ncd.jsonSHA-256 a90fadfd264b9ef4…
Disclaimer
This page reproduces the CMS National Coverage Determination text and, for laboratory NCDs, the CMS ICD-10 edit lists, as an operational reference. Coverage decisions depend on the full policy, the claim and the contractor; nothing here is legal, clinical or billing advice. CPT codes are shown as numbers only; CPT descriptors are copyright AMA.