ICD-9-CM Diagnosis Code 436 Acute, but ill-defined, cerebrovascular disease Apoplexy, apoplectic: Apoplexy, apoplectic: NOS seizure Attack Cerebral seizure Cerebral Once the acute stage is passed, you can code any late or residual effects from the original occurrence. Reference: ICD-9-CM codes are used in medical billing and coding to describe diseases, injuries, symptoms and conditions.