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G46.2 ICD-10-CM Code: Posterior cerebral artery syndrome

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Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives
1 code-first instruction

Billable · FY2027A valid, specific ICD-10-CM code, reportable for dates of service in FY2027.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too; the Instructions section marks which is which.

Code firstSequence the underlying condition before this code
  • underlying cerebrovascular disease (I60-I69)

CompareCheck ClaimView Related Codes

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v44, Appendix B.

  • MS-DRG 061 — ISCHEMIC STROKE, PRECEREBRAL OCCLUSION OR TRANSIENT ISCHEMIA WITH THROMBOLYTIC AGENT WITH MCC (MDC 01)
  • MS-DRG 062 — ISCHEMIC STROKE, PRECEREBRAL OCCLUSION OR TRANSIENT ISCHEMIA WITH THROMBOLYTIC AGENT WITH CC (MDC 01)
  • MS-DRG 063 — ISCHEMIC STROKE, PRECEREBRAL OCCLUSION OR TRANSIENT ISCHEMIA WITH THROMBOLYTIC AGENT WITHOUT CC/MCC (MDC 01)
  • MS-DRG 069 — TRANSIENT ISCHEMIA WITHOUT THROMBOLYTIC (MDC 01)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for G46.2 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on G46.2 itself; “inherited from” names the category or block whose note applies here.

Code First

Underlying conditions that must be sequenced before this code.

  • underlying cerebrovascular disease (I60-I69)

Source: inherited from G46

Coder workflow for G46.2

MedCoder structured workflow — derived from this code’s own official record

Choose the right path

  1. Is the underlying (etiologic) condition the Code First note names documented?
    Yes → Sequence the underlying condition first, then G46.2.
    No → Continue; do not add an underlying condition the record does not document.

Consider G46.2. Then confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
The underlying (etiologic) condition
Named in the Code First note; sequenced before this code when documented (Guidelines I.A.13).

Official instructions as workflow

  • Code First — sequencing check(1 note)

    Coding workflow: Check whether the underlying or etiologic condition the note names is documented. When it is, sequence it before G46.2. Do not add an underlying condition the record does not document.

    See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: The underlying condition the Code First note names is documented alongside this condition.

Coding question: How are the two sequenced?

Path: Review the Code First note.

Reason: The underlying condition is sequenced first and the manifestation follows (Guidelines I.A.13).

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Posterior cerebral artery syndrome is a billable ICD-10-CM diagnosis code (G46.2).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

  • CC as a secondary diagnosis (FY2027). Can raise the stay's MS-DRG severity tier.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder-derived relationships — computed from published CMS and AHRQ datasets

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 115 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 4 MS-DRGs: DRG 061 (MDC 01), DRG 062 (MDC 01), DRG 063 (MDC 01), DRG 069 (MDC 01).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):NVS020 — Other nervous system disorders (neither hereditary nor degenerative) (default); CIR024 — Other and ill-defined cerebrovascular disease.

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

E13.65 — Other specified diabetes mellitus with hyperglycemia, E13.69 — Other specified diabetes mellitus with other specified complication, E13.8 — Other specified diabetes mellitus with unspecified complications, G45.0 — Vertebro-basilar artery syndrome, G45.1 — Carotid artery syndrome (hemispheric), G45.2 — Multiple and bilateral precerebral artery syndromes, G45.8 — Other transient cerebral ischemic attacks and related syndromes, G45.9 — Transient cerebral ischemic attack, unspecified, G46.0 — Middle cerebral artery syndrome, G46.1 — Anterior cerebral artery syndrome, I27.841 — Fontan-associated lymphatic dysfunction, I27.848 — Other Fontan-associated condition, I27.849 — Fontan related circulation, unspecified, I63.00 — Cerebral infarction due to thrombosis of unspecified precerebral artery, I63.011 — Cerebral infarction due to thrombosis of right vertebral artery, I63.012 — Cerebral infarction due to thrombosis of left vertebral artery, I63.013 — Cerebral infarction due to thrombosis of bilateral vertebral arteries, I63.019 — Cerebral infarction due to thrombosis of unspecified vertebral artery, I63.02 — Cerebral infarction due to thrombosis of basilar artery, I63.031 — Cerebral infarction due to thrombosis of right carotid artery, +94 more

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Other nervous system disorders (neither hereditary nor degenerative), Other and ill-defined cerebrovascular disease).

G37.2 — Central pontine myelinolysis, G37.3 — Acute transverse myelitis in demyelinating disease of central nervous system, G37.4 — Subacute necrotizing myelitis of central nervous system, G37.5 — Concentric sclerosis [Balo] of central nervous system, G37.8 — Other specified demyelinating diseases of central nervous system, G37.81 — Myelin oligodendrocyte glycoprotein antibody disease, G37.89 — Other specified demyelinating diseases of central nervous system, G37.9 — Demyelinating disease of central nervous system, unspecified, G46.0 — Middle cerebral artery syndrome, G46.1 — Anterior cerebral artery syndrome, G46.3 — Brain stem stroke syndrome, G46.4 — Cerebellar stroke syndrome, G46.5 — Pure motor lacunar syndrome, G46.6 — Pure sensory lacunar syndrome, G46.7 — Other lacunar syndromes, G46.8 — Other vascular syndromes of brain in cerebrovascular diseases, G64 — Other disorders of peripheral nervous system, G90.8 — Other disorders of autonomic nervous system, G90.81 — Serotonin syndrome, G90.89 — Other disorders of autonomic nervous system, +116 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Lipid Panel, Prothrombin Time Test and INR (PT/INR)

Contextual Map

Every relationship of G46.2 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Hierarchy

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

  • MDC 01 — Diseases and Disorders of the Nervous System[MDC crossing]: “Diseases and Disorders of the Nervous System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 8,919 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Index entries

  • Syndrome, cerebral, artery, posterior[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027

Nearest codes (9)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Indexed Clinical Terms (1)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44 Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 20, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "G46.2 — Posterior cerebral artery syndrome." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/g46.2-posterior-cerebral-artery-syndrome

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Posterior cerebral artery syndrome

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to G46.2 in its code family, with their registry titles.

View all codes in the G46 family