ICD-10-CM 2027
ICD-10 code for Corticobasal degeneration
From the official ICD-10-CM alphabetic index entry “Degeneration, degenerative › corticobasal”. Page updated September 29, 2026.
About coding Corticobasal degeneration
The ICD-10-CM code for Corticobasal degeneration is G31.85 (Corticobasal degeneration).
Within G31.8 (other specified degenerative diseases of nervous system), G31.85 is specifically for Corticobasal degeneration. Related codes cover leukodystrophy, unspecified (G31.80), Alpers disease (G31.81), Leigh's disease (G31.82), neurocognitive disorder with Lewy bodies (G31.83), mild cognitive impairment of uncertain or unknown etiology (G31.84), Alexander disease (G31.86), primary progressive apraxia of speech (G31.87) and other specified degenerative diseases of nervous system (G31.89).
Use an additional code, if applicable, for codes G31.0-G31.83, G31.85-G31.9, to identify: dementia with anxiety (F02.84, F02.A4, F02.B4, F02.C4), dementia with behavioral disturbance (F02.81-, F02.A1-, F02.B1-, F02.C1-), dementia with mood disturbance (F02.83, F02.A3, F02.B3, F02.C3), dementia with psychotic disturbance (F02.82, F02.A2, F02.B2, F02.C2), dementia without behavioral disturbance (F02.80, F02.A0, F02.B0, F02.C0) and 1 more.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
Common questions about Corticobasal degeneration ICD-10 codes
What is the ICD-10 code for Corticobasal degeneration?
- G31.85 — Corticobasal degeneration.
Is G31.85 billable?
- Yes. G31.85 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can G31.85 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict G31.85 as a principal diagnosis.
Is G31.85 a CC or MCC?
- No. G31.85 is neither a CC nor an MCC under MS-DRG v44.0.