ICD-10-CM 2027
ICD-10 code for cornea degeneration
From the official ICD-10-CM alphabetic index entry “Degeneration, degenerative › cornea”. Page updated September 29, 2026.
About coding cornea degeneration
The ICD-10-CM code for cornea degeneration is H18.40 (Unspecified corneal degeneration). The official index lists 7 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on H18.40.
Within H18.4, choose H18.40 (Unspecified corneal degeneration) only when documentation doesn't support a more specific option: Arcus senilis (H18.41), band keratopathy (H18.42), other calcerous corneal degeneration (H18.43), keratomalacia (H18.44), nodular corneal degeneration (H18.45), peripheral corneal degeneration (H18.46) and other corneal degeneration (H18.49).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 124 (Other Disorders of the Eye with MCC or Thrombolytic Agent, relative weight 1.2471) and DRG 125 (Other Disorders of the Eye without MCC, relative weight 0.7702), in MDC 02 (Diseases and Disorders of the Eye), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific cornea degeneration codes (official index)
- calcerous H18.43 — Other calcerous corneal degeneration
- band keratopathy H18.42 — Band keratopathy
- familial, hereditary
- hyaline (of old scars) H18.49 — Other corneal degeneration
- keratomalacia
- nodular H18.45 — Nodular corneal degeneration
- peripheral H18.46 — Peripheral corneal degeneration
- senile H18.41 — Arcus senilis
- specified type NEC H18.49 — Other corneal degeneration
Common questions about cornea degeneration ICD-10 codes
What is the ICD-10 code for cornea degeneration?
- H18.40 — Unspecified corneal degeneration. More specific codes apply when the documentation supports them: H18.43, H18.42, H18.49, H18.45 and others below.
What is the ICD-10 code for calcerous cornea degeneration?
- H18.43 — Other calcerous corneal degeneration.
What is the ICD-10 code for hyaline cornea degeneration?
- H18.49 — Other corneal degeneration.
What is the ICD-10 code for nodular cornea degeneration?
- H18.45 — Nodular corneal degeneration (header code; choose a more specific subcode).
What is the ICD-10 code for peripheral cornea degeneration?
- H18.46 — Peripheral corneal degeneration (header code; choose a more specific subcode).
What is the ICD-10 code for senile cornea degeneration?
- H18.41 — Arcus senilis (header code; choose a more specific subcode).
Is H18.40 billable?
- Yes. H18.40 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can H18.40 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict H18.40 as a principal diagnosis.
Is H18.40 a CC or MCC?
- No. H18.40 is neither a CC nor an MCC under MS-DRG v44.0.