H40.1121 (Primary open-angle glaucoma, left eye, mild stage) compared with H40.1191 (Primary open-angle glaucoma, unspecified eye, mild stage), from the official CMS tabular data. H40.1121 and H40.1191 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. H40.1121 and H40.1191 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.
| H40.1121Primary open-angle glaucoma, left eye, mild stage | H40.1191Primary open-angle glaucoma, unspecified eye, mild stage | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | H00-H59 — Diseases of the eye and adnexa | H00-H59 — Diseases of the eye and adnexa |
| Definition | Primary open-angle glaucoma, left eye, mild stage is a billable ICD-10-CM diagnosis code (H40.1121). | Primary open-angle glaucoma, unspecified eye, mild stage is a billable ICD-10-CM diagnosis code (H40.1191). |
| 7th character | One of the following 7th characters is to be assigned to each code in subcategory H40.11 to designate the stage of glaucoma | One of the following 7th characters is to be assigned to each code in subcategory H40.11 to designate the stage of glaucoma |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources