G91.9Billable

Hydrocephalus, unspecified

Chapter
6. Diseases of the nervous system
Category
G91
Effective date
October 1, 2026

Related codes in category G91

G91HydrocephalusG91.0Communicating hydrocephalusYesG91.1Obstructive hydrocephalusYesG91.2(Idiopathic) normal pressure hydrocephalusYesG91.3Post-traumatic hydrocephalus, unspecifiedYesG91.4Hydrocephalus in diseases classified elsewhereYesG91.8Other hydrocephalusYes

Frequently asked questions

What is ICD-10 code G91.9?

G91.9 is an ICD-10-CM diagnosis code for Hydrocephalus, unspecified.

Is G91.9 a billable code?

Yes. G91.9 is billable and specific enough to be used on a claim.

What ICD-10-CM chapter is G91.9 in?

G91.9 falls under Chapter 6: Diseases of the nervous system.

When did G91.9 become effective?

G91.9 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.

What other codes are related to G91.9?

G91.9 belongs to category G91, which includes 7 other codes — see the related codes list on this page.

ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.