Is H21.512 a billable ICD-10-CM code?

Yes. H21.512 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does H21.512 sit in the tabular list?

Diseases of the eye and adnexa (H00-H59), in the block Disorders of sclera, cornea, iris and ciliary body (H15-H22).

What cannot be coded together with H21.512?

H21.512 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above H21.512 (H21.5) and apply to it just the same.

H21.512

H21.512 — Anterior synechiae (iris), left eye

Billable / specific codeICD-10-CMleft

H21.512 is a billable, specific ICD-10-CM code for anterior synechiae (iris), left eye. It is valid for submission on a claim.

Excludes1 inherited from the categories above H21.512

These are not written on H21.512, but they bind it: a note on a category applies to every code beneath it. Billing H21.512 with anything listed here is a denial.

Written on H21.5 — Other and unspecified adhesions and disruptions of iris and ciliary body

corectopia (Q13.2)

Excludes2 inherited from the categories above H21.512

Also inherited, and the opposite of Excludes1: these conditions are not part of H21.512, but a patient can have both, so you may code both.

Written on H21 — Other disorders of iris and ciliary body

sympathetic uveitis (H44.1-)

Risk adjustment

H21.512 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

H21.512 is named in 7 Medicare coverage policies — 7 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A53060Billing and Coding: Ophthalmology: Extended Ophthalmoscopy and Fundus Photography
A56537Billing and Coding: Scanning Computerized Ophthalmic Diagnostic Imaging (SCODI)
A56726Billing and Coding: Ophthalmology: Posterior Segment Imaging (Extended Ophthalmoscopy and Fundus Photography)
A57068Billing and Coding: Ocular Photography - External

Code history

H21.512 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share H21.51. If H21.512 is not quite right, the correct code is usually one of these.

Questions about H21.512

Is H21.512 a billable ICD-10-CM code?: Yes. H21.512 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does H21.512 sit in the tabular list?: Diseases of the eye and adnexa (H00-H59), in the block Disorders of sclera, cornea, iris and ciliary body (H15-H22).
What cannot be coded together with H21.512?: H21.512 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above H21.512 (H21.5) and apply to it just the same.