Coding and coverage · ICD-10-CM

H40 › H40.1

H40.10 Unspecified open-angle glaucoma

Not billable (header)Chapter 7

This code needs a 7th character (use X as a placeholder for missing characters).

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Codes under this one

  • H40.10X0 Unspecified open-angle glaucoma, stage unspecified
  • H40.10X1 Unspecified open-angle glaucoma, mild stage
  • H40.10X2 Unspecified open-angle glaucoma, moderate stage
  • H40.10X3 Unspecified open-angle glaucoma, severe stage
  • H40.10X4 Unspecified open-angle glaucoma, indeterminate stage

Instructional notes

Chapter 7

Excludes2Not included here: the patient may have both; report both when both are present.
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • diabetes mellitus related eye conditions (E09.3-, E10.3-, E11.3-, E13.3-)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury (trauma) of eye and orbit (S05.-)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • syphilis related eye disorders (A50.01, A50.3-, A51.43, A52.71)
Notes
  • Use an external cause code following the code for the eye condition, if applicable, to identify the cause of the eye condition

H40

Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.
  • absolute glaucoma (H44.51-)
  • congenital glaucoma (Q15.0)
  • traumatic glaucoma due to birth injury (P15.3)

This code

7th charactersOne of the following 7th characters is to be assigned to code H40.10 to designate the stage of glaucoma
  • 0 stage unspecified
  • 1 mild stage
  • 2 moderate stage
  • 3 severe stage
  • 4 indeterminate stage

Chapter 7: Diseases of the eye and adnexa · H40-H42 Glaucoma (H40-H42)

Source: ICD-10-CM FY 2027 code descriptions and tabular list (CMS and CDC National Center for Health Statistics), effective 2026-10-01 through 2027-09-30 · CMS ICD-10 files. HCC mapping: CMS-HCC V28, payment year 2027. As of 2026-11-04.

Coverage and payment depend on the claim details; confirm with the Medicare Administrative Contractor.