Question 1

What is ICD-10 code G94?

Accepted Answer

G94 is the ICD-10-CM diagnosis code for other disorders of brain in diseases classified elsewhere. Brain disorders that occur as a result of another disease classified elsewhere, such as brain involvement in systemic infections or metabolic disorders. G94 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering other disorders of the nervous system (g89-g99).

G94 is a billable ICD-10-CM code, but the current payload does not show a mapping under the CMS-HCC V28 or V24 community payment models, and none under the ESRD, Part D RxHCC, or HHS-HCC models. Do not assign risk adjustment value from this page when no source-backed mapping is shown; verify the applicable model and payment year.

This code requires a secondary code to identify the underlying disease causing the brain disorder.

Question 2

Is G94 an HCC code?

Accepted Answer

G94 has no payable CMS-HCC V28 mapping in the final FY2026 CMS file.

Question 3

Is G94 billable?

Accepted Answer

Yes. G94 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. G94 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Question 4

Which HCC does G94 map to under V28?

Accepted Answer

G94 has no payable CMS-HCC V28 mapping in the final FY2026 CMS file.

Question 5

What RAF reference is published for G94?

Accepted Answer

G94 has no V28 reference coefficient because the final FY2026 source verifies no payable V28 mapping.

Question 6

What is the V28 vs V24 difference for G94?

Accepted Answer

G94 has verified no payable V28 mapping in the final FY2026 source. Select a historical effective period before making any V24 comparison.

Question 7

What documentation supports G94?

Accepted Answer

This code requires a secondary code to identify the underlying disease causing the brain disorder Use the 'in diseases classified elsewhere' convention; code the primary condition first G94 is not a CMS-HCC V28 payment code in the verified current source, so MEAT is not the payment hook. Documentation still has to support the diagnosis if you report it.

Question 8

Can G94 be a primary diagnosis?

Accepted Answer

No. G94 is a manifestation code, so it is never the first-listed diagnosis. The tabular instruction is to code first underlying disease, then report G94 as a secondary code. Sequencing does not change its CMS-HCC V28 category.

Question 9

Which codes cannot be reported with G94?

Accepted Answer

The Excludes1 note that applies to G94 lists encephalopathy in congenital syphilis (A50.49); encephalopathy in influenza (J09.X9, J10.81, J11.81); encephalopathy in syphilis (A52.19); hydrocephalus in diseases classified elsewhere (G91.4). An Excludes1 condition is not reported together with G94; report one or the other, unless the two conditions are unrelated, which the ICD-10-CM Official Guidelines (Section I.A.12.a) allow. The Excludes2 note lists certain conditions originating in the perinatal period (P04-P96); certain infectious and parasitic diseases (A00-B99); complications of pregnancy, childbirth and the puerperium (O00-O9A); congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99); and 4 more (see the notes on this page); those are separate conditions that may be reported together with G94 when both are documented.

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G94

Is G94 an HCC code?

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What This Code Means

Coding Tips

Excludes 1, Do NOT code together

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Code Hierarchy

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G94 ICD-10-CM Code: Other disorders of brain in diseases classified elsewhere

HCC Buddy Code Card

G94

Is G94 an HCC code?

Get the V28 mapping + MEAT cheat sheet

What This Code Means

Coding Tips

Excludes 1, Do NOT code together

Code First

Code Hierarchy

Work G94 in HCC Buddy