I63.321 (Cerebral infarction due to thrombosis of right anterior cerebral artery) compared with I63.322 (Cerebral infarction due to thrombosis of left anterior cerebral artery), from the official CMS tabular data. I63.321 and I63.322 code the same condition on opposite sides. MedCoder-derived
Same condition; these differ only in which side is documented.
These codes share a category and title and differ only in the side affected. The documentation decides which applies, and a bilateral code is reported only where the code set provides one.
Source: ICD-10-CM tabular list (laterality variant derived from the code title)
Same condition, opposite side. I63.321 and I63.322 name the same condition on opposite sides of the body.
Same category and title, differing only in which side is affected — the documentation decides which one applies, and a bilateral code is reported only where the code set provides one.
| I63.321Cerebral infarction due to thrombosis of right anterior cerebral artery | I63.322Cerebral infarction due to thrombosis of left anterior cerebral artery | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | I00-I99 — Diseases of the circulatory system | I00-I99 — Diseases of the circulatory system |
| Definition | Cerebral infarction due to thrombosis of right anterior cerebral artery is a billable ICD-10-CM diagnosis code (I63.321). | Cerebral infarction due to thrombosis of left anterior cerebral artery is a billable ICD-10-CM diagnosis code (I63.322). |
| Includes | occlusion and stenosis of cerebral and precerebral arteries, resulting in cerebral infarction | occlusion and stenosis of cerebral and precerebral arteries, resulting in cerebral infarction |
| Use additional code | code, if applicable, to identify status post administration of tPA (rtPA) in a different facility within the last 24 hours prior to admission to current facility (Z92.82) code, if known, to indicate National Institutes of Health Stroke Scale (NIHSS) score (R29.7-) code to identify presence of: | code, if applicable, to identify status post administration of tPA (rtPA) in a different facility within the last 24 hours prior to admission to current facility (Z92.82) code, if known, to indicate National Institutes of Health Stroke Scale (NIHSS) score (R29.7-) code to identify presence of: |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources