Q04.3

Billable code

Other reduction deformities of brain

The ICD-10 code for other reduction deformities of brain is Q04.3.

Clinical notes

Excludes1 (not coded here)

An Excludes1 note is a pure exclusion: the excluded condition and this code should never be reported together, because the two conditions cannot occur at the same time (e.g. a congenital form vs. an acquired form of the same disease).

congenital malformations of corpus callosum (Q04.0)

Also known as

Alternate wording, synonyms, or specific conditions that fall under this code, listed to help confirm you've picked the right one.

Absence of part of brain
Agenesis of part of brain
Agyria
Aplasia of part of brain
Hydranencephaly
Hypoplasia of part of brain
Lissencephaly
Microgyria
Pachygyria

Documentation support

General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.

•Confirm the excluded condition(s) listed above are not also present — Excludes1 conditions cannot be coded together with this one.
•As a general rule, code to the highest level of specificity supported by the documentation in the medical record.

ICD-9-CM equivalent

Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.

7422Approximate match

View full ICD-10 → ICD-9 crosswalk →

Associated MS-DRGs

Q04.3 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.

Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.