H18.4 – Corneal degeneration

ICD-10-CM 2027 diagnosis code · Disorders of sclera, cornea, iris and ciliary body

Non-billable header

ICD-10-CM code H18.4

Code: H18.4 (claims format: H184)
Description: Corneal degeneration
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 7. Diseases of the eye and adnexa (H00-H59)
Block: H15-H22 Disorders of sclera, cornea, iris and ciliary body
Parent codes: H18

Billable codes under H18.4

H18.4 is a header code and cannot be used on claims. Choose the most specific code:

H18.40 – Unspecified corneal degenerationBillable
H18.41 – Arcus senilisHeader (more codes below)
H18.42 – Band keratopathyHeader (more codes below)
H18.43 – Other calcerous corneal degenerationBillable
H18.44 – KeratomalaciaHeader (more codes below)
H18.45 – Nodular corneal degenerationHeader (more codes below)
H18.46 – Peripheral corneal degenerationHeader (more codes below)
H18.49 – Other corneal degenerationBillable

Notes for H18.4

Excludes1 (not coded here):

Mooren's ulcer (H16.0-)
recurrent erosion of cornea (H18.83-)

Related codes in H18

H18.0 – Corneal pigmentations and depositsHeader
H18.1 – Bullous keratopathyHeader
H18.2 – Other and unspecified corneal edemaHeader
H18.3 – Changes of corneal membranesHeader
H18.5 – Hereditary corneal dystrophiesHeader
H18.6 – KeratoconusHeader
H18.7 – Other and unspecified corneal deformitiesHeader
H18.8 – Other specified disorders of corneaHeader
H18.9 – Unspecified disorder of corneaBillable

Frequently asked questions

What is ICD-10 code H18.4?

H18.4 is the ICD-10-CM code for corneal degeneration, in the block H15-H22 (Disorders of sclera, cornea, iris and ciliary body).

Is H18.4 a billable code?

No. H18.4 is a header code with more specific child codes; report one of the billable codes listed above.

What category does H18.4 belong to?

It belongs to category H18 – Other disorders of cornea.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.