H16.02 ICD-10-CM Code: Ring corneal ulcer

Coder workflow for H16.02

MedCoder structured workflow — derived from this code’s own official record

Before you code H16.02

1. H16.02 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).

   ReviewH16.021, H16.022, H16.023, H16.029

   See the relationships section · Guide: How to choose an ICD-10-CM code →

Choose the right path

1. Does the documentation support one of the more specific codes beneath H16.02?
   Yes → Select that code and continue the checks below on its own page.
   No → H16.02 cannot be reported as written; query for the specificity its subcategory needs.

   ReviewH16.021, H16.022, H16.023, H16.029

Consider H16.02. Then confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement

Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Don’t confuse H16.02 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of H16.02 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

• H16.00— Specificity relationship (Review)

  Overlapping diagnoses in the same category.

  Overlapping codes in the same category — the documentation decides which is the more specific fit.

  What moves you there: A record that documents no more than “Unspecified corneal ulcer” takes H16.00; specificity in the record moves it back here.

  Full comparison: H16.02 vs H16.00 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Verify Before Coding

• Not billable as written — a more specific code is required: H16.021, H16.022, H16.023, H16.029.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name H16.02 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Excludes1 note: H18.4 — Corneal degeneration (via H16.0.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 1 Use Additional Code instruction: L51 — Erythema multiforme (via H16.0.-).

These codes instruct coders to additionally report this code when it applies.

Contextual Map

Every relationship of H16.02 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run H16.02 with these 2 related codes in Claim Check

Hierarchy

• H00-H59 — Chapter 7: Diseases of the Eye and Adnexa (H00-H59) (H00-H59)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H15-H22 — Disorders of sclera, cornea, iris and ciliary body[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes1 notes

• H18.4 — Corneal degeneration[Excludes1](via H16.0.-): “Mooren's ulcer (H16.0-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Use Additional Code instructions

• L51 — Erythema multiforme[Use Additional Code](via H16.0.-): “corneal ulcer (H16.0-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Nearest codes (40)

• H16 — Keratitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H16.0 — Corneal ulcer[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H16.00 — Unspecified corneal ulcer[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H16.001 — Unspecified corneal ulcer, right eye[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H16.002 — Unspecified corneal ulcer, left eye[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H16.003 — Unspecified corneal ulcer, bilateral[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H16.009 — Unspecified corneal ulcer, unspecified eye[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H16.01 — Central corneal ulcer[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• and 32 more

Change history

• FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Common coding questions

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data

CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page

Claim edits Official source data

CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page

Change history and date-of-service validity Official source data

CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page

Comparisons, relationships and the contextual map MedCoder structured relationship

Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears

Summary and FAQ answers MedCoder explanation

Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Nearest Codes in This Family

Official ICD-10-CM classifications closest to H16.02 in its code family, with their registry titles.

• H16.01 — Central corneal ulcer
• H16.011 — Central corneal ulcer, right eye
• H16.012 — Central corneal ulcer, left eye
• H16.013 — Central corneal ulcer, bilateral
• H16.019 — Central corneal ulcer, unspecified eye
• H16.021 — Ring corneal ulcer, right eye
• H16.022 — Ring corneal ulcer, left eye
• H16.023 — Ring corneal ulcer, bilateral
• H16.029 — Ring corneal ulcer, unspecified eye
• H16.03 — Corneal ulcer with hypopyon

View all codes in the H16 family