H21.21 Degeneration of chamber angle

The ICD-10-CM code for Degeneration of chamber angle is H21.21 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Chapter

7: Diseases of the eye and adnexa (H00-H59)

Section

H15-H22: Disorders of sclera, cornea, iris and ciliary body (H15-H22)

Category H21

126 codes (97 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to H21.21:

• Degeneration, degenerative › chamber angle

Official Coding Guidelines

Glaucoma (TOC entry)

a. Glaucoma .............................................................................................................................. 48

Assigning glaucoma codes (use as many H40 codes as needed)

Assign as many codes from category H40, Glaucoma, as needed to identify the type of glaucoma, the affected eye, and the glaucoma stage.

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool