G91
Non-billableHydrocephalus
Hydrocephalus
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Includes
Conditions included under this code
- acquired hydrocephalus
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- 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)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Child Codes (7)
G91.0Communicating hydrocephalus
G91.1Obstructive hydrocephalus
G91.2(Idiopathic) normal pressure hydrocephalus
G91.3Post-traumatic hydrocephalus, unspecified
G91.4Hydrocephalus in diseases classified elsewhere
G91.8Other hydrocephalus
G91.9Hydrocephalus, unspecified
Also Known As / Clinical Terms
UMLS
- Acquired HydrocephalusC0270716
- Acquired hydrocephalusC0270716
- Acquired hydrocephalus (disorder)C0270716
- Hydrocephalus acquiredC0270716
- acquired hydrocephalusC0270716
- HydrocephalusC0020255
- Hydrocephalus (disorder)C0020255
- Hydrocephalus NOSC0020255
- Hydrocephalus, unspecifiedC0020255
- HydrocephalyC0020255
- Nonsyndromal hydrocephalusC0020255
- Too much cerebrospinal fluid in the brainC0020255
- Water on the brainC0020255
- hydrencephalusC0020255
- hydrencephalyC0020255
- hydrocephalusC0020255
- hydrocephalyC0020255
Frequently Asked Questions
What is ICD-10 code G91?
ICD-10-CM code G91 represents "Hydrocephalus". It is a non-billable header code — use a more specific child code for billing purposes.
Is G91 a billable code?
No, G91 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 7 child codes under G91.
What chapter is G91 in?
G91 is in Chapter 6: Diseases of the Nervous System (codes G00-G99).
What codes cannot be used with G91?
G91 has Excludes1 notes indicating codes that cannot be used together with it, including: Arnold-Chiari syndrome with hydrocephalus (Q07.-); congenital hydrocephalus (Q03.-); spina bifida with hydrocephalus (Q05.-).
What are the subcategories under G91?
G91 has 7 child codes, including: G91.0 (Communicating hydrocephalus), G91.1 (Obstructive hydrocephalus), G91.2 ((Idiopathic) normal pressure hydrocephalus), G91.3 (Post-traumatic hydrocephalus, unspecified), and 3 more.
What are the UMLS CUIs for G91?
G91 is linked to 2 UMLS Concept Unique Identifiers: C0270716, C0020255. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.