H21.51 – Anterior synechiae (iris)

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

Non-billable header

ICD-10-CM code H21.51

Code: H21.51 (claims format: H2151)
Description: Anterior synechiae (iris)
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: H21 › H21.5

Billable codes under H21.51

H21.51 is a header code and cannot be used on claims. Choose the most specific code:

H21.511 – Anterior synechiae (iris), right eyeBillable
H21.512 – Anterior synechiae (iris), left eyeBillable
H21.513 – Anterior synechiae (iris), bilateralBillable
H21.519 – Anterior synechiae (iris), unspecified eyeBillable

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

H21 – Other disorders of iris and ciliary body

Excludes2 (not included here):

sympathetic uveitis (H44.1-)

H21.5 – Other and unspecified adhesions and disruptions of iris and ciliary body

Excludes1 (not coded here):

corectopia (Q13.2)

Index terms for H21.51

Entries in the ICD-10-CM alphabetic index that lead to this code:

Adhesions, adhesive, iris, anterior

Related codes in H21.5

H21.50 – Unspecified adhesions of irisHeader
H21.52 – GoniosynechiaeHeader
H21.53 – IridodialysisHeader
H21.54 – Posterior synechiae (iris)Header
H21.55 – Recession of chamber angleHeader
H21.56 – Pupillary abnormalitiesHeader

Frequently asked questions

What is ICD-10 code H21.51?

H21.51 is the ICD-10-CM code for anterior synechiae (iris), in the block H15-H22 (Disorders of sclera, cornea, iris and ciliary body).

Is H21.51 a billable code?

No. H21.51 is a header code with more specific child codes; report one of the billable codes listed above.

What category does H21.51 belong to?

It belongs to category H21 – Other disorders of iris and ciliary body.

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.