331.9 CEREB DEGENERATION NOS


Code Information

Diagnosis Code: 331.9

Short Description: Cereb degeneration NOS

Long Description: Cerebral degeneration, unspecified

Code Classification:

  • Diseases of the nervous system (320–359)
    • Hereditary and degenerative diseases of the central nervous system (330-337)
      • 331 Other cerebral degenerations
        • 331.9 Cereb degeneration NOS

Code Version: 2015 ICD-9-CM


References to Index of Diseases and Injuries

The code 331.9 has the following ICD-9-CM references to the Index of Diseases and Injuries
  • Atrophy, atrophic
    • brain (cortex) (progressive) 331.9
      • with dementia 290.10
      • Alzheimer's 331.0
        • with dementia - see Alzheimer's, dementia
      • circumscribed (Pick's) 331.11
        • with dementia
          • with behavioral disturbance 331.11 [294.11]
          • without behavioral disturbance 331.11 [294.10]
      • congenital 742.4
      • hereditary 331.9
      • senile 331.2
    • cortical (see also Atrophy, brain) 331.9
  • Cirrhosis, cirrhotic 571.5
    • brain 331.9
  • Degeneration, degenerative
    • brain (cortical) (progressive) 331.9
      • arteriosclerotic 437.0
      • childhood 330.9
        • specified type NEC 330.8
      • congenital 742.4
      • cystic 348.0
        • congenital 742.4
      • familial NEC 331.89
      • grey matter 330.8
      • heredofamilial NEC 331.89
      • in
        • alcoholism 303.9 [331.7]
        • beriberi 265.0 [331.7]
        • cerebrovascular disease 437.9 [331.7]
        • congenital hydrocephalus 742.3 [331.7]
          • with spina bifida (see also Spina bifida) 741.0 [331.7]
        • Babry's disease 272.7 [330.2]
        • Gaucher's disease 272.7 [330.2]
        • Hunter's disease or syndrome 277.5 [330.3]
        • lipidosis
          • cerebral 330.1
          • generalized 272.7 [330.2]
        • mucopolysaccharidosis 277.5 [330.3]
        • myxedema (see also Myxedema) 244.9 [331.7]
        • neoplastic disease NEC (M8000/1) 239.9 [331.7]
        • Niemann-Pick disease 272.7 [330.2]
        • sphingolipidosis 272.7 [330.2]
        • vitamin B12�deficiency 266.2 [331.7]
      • motor centers 331.89
      • senile 331.2
      • specified type NEC 331.89
  • Depression 311
    • cerebral 331.9
      • newborn 779.2
  • Hypofunction
    • cerebral 331.9
  • Marasmus 261
    • brain 331.9

Crosswalk Information

The code 331.9 converts into the following ICD-10 code(s):
ICD-9 Code ICD-10 Code ICD-10 Description
331.9 Right Arrow G31.9 Degenerative disease of nervous system, unspecified
This ICD-9 to ICD-10 data is based on the 2018 General Equivalency Mapping (GEM) files published by the Centers for Medicare & Medicaid Services (CMS) for informational purposes only. The data is not an ICD-10 conversion tool and doesn’t guarantee clinical accuracy.

Similar Codes

ICD-9 Code ICD-9 Description
331.0 Alzheimer's disease
331.11 Pick's disease
331.19 Other frontotemporal dementia
331.2 Senile degeneration of brain
331.3 Communicating hydrocephalus
331.4 Obstructive hydrocephalus
331.5 Idiopathic normal pressure hydrocephalus (INPH)
331.6 Corticobasal degeneration
331.7 Cerebral degeneration in diseases classified elsewhere
331.81 Reye's syndrome
331.82 Dementia with lewy bodies
331.83 Mild cognitive impairment, so stated
331.89 Other cerebral degeneration


This page was last updated on: 10/1/2014