1. G91 Hydrocephalus

    Includes:

    • acquired hydrocephalus

    Excludes1

    • Arnold-Chiari syndrome with hydrocephalus (Q07.-)
    • congenital hydrocephalus (Q03.-)
    • spina bifida with hydrocephalus (Q05.-)
    1. G91.0 Communicating hydrocephalus

      Inclusion term(s):

      • Secondary normal pressure hydrocephalus
    2. G91.1 Obstructive hydrocephalus

    3. G91.2 (Idiopathic) normal pressure hydrocephalus

      Inclusion term(s):

      • Normal pressure hydrocephalus NOS
    4. G91.3 Post-traumatic hydrocephalus, unspecified

    5. G91.4 Hydrocephalus in diseases classified elsewhere

    6. G91.8 Other hydrocephalus

    7. G91.9 Hydrocephalus, unspecified

Abbreviations used here:

NEC Not elsewhere classifiable
This abbreviation in the Tabular List represents “other specified”. When a specific code is not available for a condition, the Tabular List includes an NEC entry under a code to identify the code as the “other specified” code.

NOS Not otherwise specified
This abbreviation is the equivalent of unspecified.