H54.2X21 ICD-10-CM Code: Low vision right eye category 2, low vision left eye category 1

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for H54.2X21 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on H54.2X21 itself; “inherited from” names the category or block whose note applies here.

7th Character Guide

• 1 — low vision left eye category 1 (this page’s code)
• 2 — low vision left eye category 2

Variant codes in this family

H54.2X21, H54.2X22

Character meanings are CMS's official 7th-character extensions for this family, as carried in each variant code's official description; variant codes are registry rows. The explanation of how the encounter character is assigned is MedCoder editorial, distinct from the official content above it.

Coder workflow for H54.2X21

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

Before you code H54.2X21

1. A 7th character is required in this family. Confirm the documentation supports the character assigned — its meaning in this family is defined in the official instruction. This page’s code carries “1”. The official 7th-character definitions for this family are quoted in the guide.

   See the 7th Character Guide

2. Laterality is coded in this family. Confirm the side documented — right, left, or bilateral — and select the matching code (this page’s code: right). The unspecified-side code applies only when the record states no side. Laterality is assigned from the documented side; where a bilateral code exists and both sides are documented, it is used instead of two unilateral codes (Guidelines I.B.13).

   See the relationships section · Guide: Laterality coding →

3. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with H54.2X21. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

   See the official tabular notes

Choose the right path

1. Does the documentation support a condition named in H54.2X21’s Excludes1 note?
   Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
   No → Continue.

   ReviewG45.3

2. Is the underlying (etiologic) condition the Code First note names documented?
   Yes → Sequence the underlying condition first, then H54.2X21.
   No → Continue; do not add an underlying condition the record does not document.
3. Is the side documented?
   Yes → Select the code for the documented side (or the bilateral code when both sides are documented and one exists).
   No → Use the unspecified-side code only when the record states no side; a query is the alternative.
4. Does the documentation support one of this family’s 7th-character values?
   Yes → Assign the matching 7th character; the variant codes are in the 7th Character Guide.
   No → The code is invalid without its 7th character — query for the missing element.

Consider H54.2X21. 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).

Laterality

Right, left or bilateral as documented; unspecified only when the record states no side (Guidelines I.B.13).

7th-character basis

The documented element this family’s 7th character records (see the official definitions in the 7th Character Guide).

The underlying (etiologic) condition

Named in the Code First note; sequenced before this code when documented (Guidelines I.A.13).

Official instructions as workflow

• Excludes1 — check before selecting H54.2X21(1 note)

  Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with H54.2X21: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

  CompareG45.3

  See the official tabular notes · Guidelines I.A.12.a

• Code First — sequencing check(1 note)

  Coding workflow: Check whether the underlying or etiologic condition the note names is documented. When it is, sequence it before H54.2X21. Do not add an underlying condition the record does not document.

  See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

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 H54.2X21 with…

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

The codes most likely to be picked instead of H54.2X21 — 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.

• G45.3— Excludes1 conflict (Excludes1 — generally not reported together)

  Not coded here — the tabular list excludes this pair for the same encounter.

  Not reported together with this code, except where the two conditions are documented as unrelated.

  What moves you there: Documentation of amaurosis fugax moves the case to G45.3; the two are not reported together unless documented as unrelated.

  Full comparison: H54.2X21 vs G45.3 →

• H54.2X22— Encounter relationship (Review)

  Same underlying diagnosis, different encounter phase.

  The same diagnosis at a different phase of care; one encounter takes one 7th character.

  What moves you there: Documentation of a low vision left eye category 2 moves the case to H54.2X22.

  Full comparison: H54.2X21 vs H54.2X22 →

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.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

1. A 7th character applies in this family. Confirm the documented encounter matches the character assigned. See the official 7th-character definitions and this code’s variants
2. Laterality is coded in this family. Confirm the documented side matches the code — the opposite-side siblings are in the relationships section. See the opposite-side sibling codes
3. Sequencing: 1 Code First instruction — the underlying condition is sequenced before this code when present. See the Code First notes
4. 1 Excludes1 entry — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes

Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.

Verify Before Coding

• No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

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 H54.2X21 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 Use Additional Code instruction: S04.0 — Injury of optic nerve and pathways (via H54.-).

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

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 2 MS-DRGs: DRG 124 (MDC 02), DRG 125 (MDC 02).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):EYE010 — Blindness and vision defects (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Blindness and vision defects).

H54.12 — Blindness, left eye, low vision right eye, H54.1213 — Low vision right eye category 1, blindness left eye category 3, H54.1214 — Low vision right eye category 1, blindness left eye category 4, H54.1215 — Low vision right eye category 1, blindness left eye category 5, H54.1223 — Low vision right eye category 2, blindness left eye category 3, H54.1224 — Low vision right eye category 2, blindness left eye category 4, H54.1225 — Low vision right eye category 2, blindness left eye category 5, H54.2 — Low vision, both eyes, H54.2X11 — Low vision right eye category 1, low vision left eye category 1, H54.2X12 — Low vision right eye category 1, low vision left eye category 2, H54.2X22 — Low vision right eye category 2, low vision left eye category 2, H54.3 — Unqualified visual loss, both eyes, H54.40 — Blindness, one eye, unspecified eye, H54.41 — Blindness, right eye, normal vision left eye, H54.413A — Blindness right eye category 3, normal vision left eye, H54.414A — Blindness right eye category 4, normal vision left eye, H54.415A — Blindness right eye category 5, normal vision left eye, H54.42 — Blindness, left eye, normal vision right eye, H54.42A3 — Blindness left eye category 3, normal vision right eye, H54.42A4 — Blindness left eye category 4, normal vision right eye, +116 more

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Low”; these codes share that main term but sit in a different category of the Tabular List.

D64.9 — Anemia, unspecified (hematocrit), E87.1 — Hypo-osmolality and hyponatremia (salt syndrome), M54.50 — Low back pain, unspecified (back syndrome), N28.89 — Other specified disorders of kidney and ureter (lying, kidney), N28.9 — Disorder of kidney and ureter, unspecified (function, kidney), P07.00 — Extremely low birth weight newborn, unspecified weight (birthweight, extreme), P07.01 — Extremely low birth weight newborn, less than 500 grams (birthweight, extreme, with weight of, 499 grams or less), P07.02 — Extremely low birth weight newborn, 500-749 grams (birthweight, extreme, with weight of, 500-749 grams), P07.03 — Extremely low birth weight newborn, 750-999 grams (birthweight, extreme, with weight of, 750-999 grams), P07.10 — Other low birth weight newborn, unspecified weight (birthweight), P07.14 — Other low birth weight newborn, 1000-1249 grams (birthweight, with weight of, 1000-1249 grams), P07.15 — Other low birth weight newborn, 1250-1499 grams (birthweight, with weight of, 1250-1499 grams), P07.16 — Other low birth weight newborn, 1500-1749 grams (birthweight, with weight of, 1500-1749 grams), P07.17 — Other low birth weight newborn, 1750-1999 grams (birthweight, with weight of, 1750-1999 grams), P07.18 — Other low birth weight newborn, 2000-2499 grams (birthweight, with weight of, 2000-2499 grams), Q17.4 — Misplaced ear (set ears), R03.1 — Nonspecific low blood-pressure reading (blood pressure, reading), R45.81 — Low self-esteem (self esteem), R79.1 — Abnormal coagulation profile (von Willebrand factor), R94.8 — Abnormal results of function studies of other organs and systems (basal metabolic rate), +3 more

Contextual Map

Every relationship of H54.2X21 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 H54.2X21 with this related code 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
• H53-H54 — Visual disturbances and blindness[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Use Additional Code instructions

• S04.0 — Injury of optic nerve and pathways[Use Additional Code](via H54.-): “code to identify any visual field defect or blindness (H53.4-, H54.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• EYE010 — Blindness and vision defects[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

MS-DRG Grouper

• DRG 124 — OTHER DISORDERS OF THE EYE WITH MCC OR THROMBOLYTIC AGENT[MS-DRG]: “OTHER DISORDERS OF THE EYE WITH MCC OR THROMBOLYTIC AGENT (MDC 02)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 125 — OTHER DISORDERS OF THE EYE WITHOUT MCC[MS-DRG]: “OTHER DISORDERS OF THE EYE WITHOUT MCC (MDC 02)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026

MDC crossing

• MDC 02 — Diseases and Disorders of the Eye[MDC crossing]: “Diseases and Disorders of the Eye — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 1,200 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Nearest codes (40)

• H54 — Blindness and low vision[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H54.1141 — Blindness right eye category 4, low vision left eye category 1[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H54.1142 — Blindness right eye category 4, low vision left eye category 2[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H54.115 — Blindness right eye category 5, low vision left eye[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H54.1151 — Blindness right eye category 5, low vision left eye category 1[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H54.1152 — Blindness right eye category 5, low vision left eye category 2[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H54.12 — Blindness, left eye, low vision right eye[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H54.121 — Low vision right eye category 1, blindness left eye[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• and 32 more

Change history

• FY2018 — Added to the code set[Change history]— CMS release files (code change ledger) · icd10cm-fy2018

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

Inpatient payment groups Official source data

CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 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 H54.2X21 in its code family, with their registry titles.

• H54.2X — Low vision, both eyes, different category levels
• H54.2X1 — Low vision, right eye, category 1
• H54.2X11 — Low vision right eye category 1, low vision left eye category 1
• H54.2X12 — Low vision right eye category 1, low vision left eye category 2
• H54.2X2 — Low vision, right eye, category 2
• H54.2X22 — Low vision right eye category 2, low vision left eye category 2
• H54.3 — Unqualified visual loss, both eyes
• H54.4 — Blindness, one eye
• H54.40 — Blindness, one eye, unspecified eye
• H54.41 — Blindness, right eye, normal vision left eye

View all codes in the H54 family