2006 ICD-9-CM Volume 1 Diagnosis Codes Home > Diseases Of The Nervous System And Sense Organs 320-389 > Hereditary And Degenerative Diseases Of The Central Nervous System 330-338 > 2006 ICD-9-CM Diagnosis 331 Other cerebral degenerations View the most recent version of ICD-9-CM 331 331 is a non-specific code that cannot be used to specify a diagnosis