ICD-10-CM › G00-G99 › G89-G99 › G codes › G91

G91

Hydrocephalus

Not billableICD-10-CM diagnosis code.

This code exists but cannot be submitted on its own. It groups the more specific codes beneath it.

A category header for its whole life, FY2016 onwards. It has never been valid for submission on its own.

Submit one of these 7 more specific codes instead:

  • G91.0 Communicating hydrocephalus
  • G91.1 Obstructive hydrocephalus
  • G91.2 (Idiopathic) normal pressure hydrocephalus
  • G91.3 Post-traumatic hydrocephalus, unspecified
  • G91.4 Hydrocephalus in diseases classified elsewhere
  • G91.8 Other hydrocephalus
  • G91.9 Hydrocephalus, unspecified

What has happened to this code

Every change the publisher made, from 2012 to now. Entries marked draft are from the pre-implementation releases: ICD-10 took effect on 1 October 2015, so nothing before FY2016 was ever valid on a claim.

  1. FY2012 Added to the draft code set draft Hydrocephalus

Official coding rules

Published by CDC for FY2027. A rule attached to a category binds every code beneath it, so the rules inherited from this code's ancestors are shown with the code they come from.

This code

Excludes1 - never coded here

  • Arnold-Chiari syndrome with hydrocephalus (Q07.-)
  • congenital hydrocephalus (Q03.-)
  • spina bifida with hydrocephalus (Q05.-)

Includes

  • acquired hydrocephalus