H54.42A4

H54.42A4: Blindness Left Eye Category 4, Normal Vision Right Eye

Code Overview

ICD-10-CM H54.42A4 is a high-specificity diagnostic code used to classify a distinct clinical state of unilateral blindness. This code specifically identifies that the left eye has reached Visual Impairment Category 4, representing a stage of near-total vision loss, while the right eye remains within “normal” functional parameters. This distinction is critical for both clinical rehabilitation planning and accurate statistical morbidity reporting.

Quick Reference

Attribute	Value
Code	H54.42A4
Description	Blindness left eye category 4, normal vision right eye
Code Type	ICD-10-CM Diagnosis
Billable	Yes
Effective Date	October 1, 2017
2026 Status	Active/No Changes
Chapter	H00-H59 (Diseases of the Eye and Adnexa)
Category	H54 (Blindness and Low Vision)

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Code Hierarchy & Tree Structure

Full Code Path

H00-H59 Diseases of the Eye and Adnexa └── H54 Blindness and Low Vision └── H54.4 Blindness, One Eye └── H54.42 Blindness, Left Eye, Normal Vision Right Eye └── H54.42A Blindness, Left Eye, Category 3-5 └── H54.42A4 Blindness Left Eye Category 4, Normal Vision Right Eye

Parent Codes

Code	Description	Billable
H54	Blindness and low vision	No
H54.4	Blindness, one eye	No
H54.42	Blindness, left eye, normal vision right eye	No
H54.42A	Blindness, left eye, category 3-5	No

Sibling Codes (Same Parent H54.42A)

Code	Description
H54.42A3	Blindness left eye category 3, normal vision right eye
H54.42A4	Blindness left eye category 4, normal vision right eye
H54.42A5	Blindness left eye category 5, normal vision right eye

Related Codes (Same Parent H54.42)

Code	Description
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
H54.42A3	Blindness left eye category 3, normal vision right eye
H54.42A4	Blindness left eye category 4, normal vision right eye
H54.42A5	Blindness left eye category 5, normal vision right eye

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🌲 Enhanced Code Hierarchy (Tree)

The path to this specific code reflects a progression from general anatomical involvement to precise lateralization and severity:

• Chapter 7: Diseases of the eye and adnexa (H00-H59)

  • Section: Visual disturbances and blindness (H53-H54) — Focuses on functional deficits rather than just physical pathology.

    • Category: H54 - Blindness and low vision — The primary category for all levels of sight loss.

      • Subcategory: H54.4- - Blindness, one eye — Isolates unilateral cases from bilateral impairments.

        • Sub-subcategory: H54.42 - Blindness, left eye, normal vision right eye — Specifies which eye is affected and the health of the fellow eye.

          • Specific Code: H54.42A4 — The terminal digit “4” confirms the exact WHO-defined category of impairment.

Visual Acuity Category Definitions

WHO Visual Impairment Categories

The H54 code series uses standardized visual impairment categories based on presenting visual acuity:

Category	Classification	Visual Acuity (Better Eye)	Description
Category 0	Normal Vision	20/20 to 20/60	No visual impairment
Category 1	Mild Vision Loss	20/70 to 20/160	Low vision
Category 2	Moderate Vision Loss	20/200 to 20/400	Low vision
Category 3	Severe Vision Loss	20/500 to 20/1000	Borderline blindness
Category 4	Blindness	<20/1000 to Light Perception	Legal blindness
Category 5	Blindness	No Light Perception	Complete blindness

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Category 4 Specific Criteria

Category 4 blindness is defined as:

• Presenting visual acuity worse than 20/1000 (1/60) with light perception in the affected eye
• Central visual acuity of 20/200 or less meets legal blindness criteria in the United States
• Visual field of 20 degrees or less may also qualify as legal blindness

Documentation Requirements

For accurate coding of H54.42A4, the medical record must document:

1. Left eye visual acuity measurement in category 4 range
2. Right eye visual acuity confirmed as normal (category 0)
3. Visual acuity measured with presenting correction (glasses/contacts if normally worn)
4. Underlying cause of blindness should be coded first per coding guidelines

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Coding Guidelines & Rules

Code First Requirement

Code first any associated underlying cause of the blindness

Examples of underlying conditions that should be coded first:

• Diabetic retinopathy (E08-E13 with .3- extension)
• Glaucoma (H40.-)
• Age-related macular degeneration (H35.3-)
• Retinal detachment (H33.-)
• Optic nerve disorders (H47.0-)
• Traumatic eye injury (S05.-)

Excludes1 Notes

Excludes1 Code	Description
G45.31	Amaurosis fugax (transient visual loss)

Note: Excludes1 means “NOT CODED HERE” - these conditions cannot be coded together with H54.42A4.

Type 2 Excludes (Chapter Level H00-H59)

The following conditions are excluded from this chapter and should be coded separately:

• Certain conditions originating in the perinatal period (P04-P96)
• Certain infectious and parasitic diseases (A00-B99)
• Complications of pregnancy, childbirth and the puerperium (O00-O9A)
• Congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
• Diabetes mellitus related eye conditions (E09.3-, E10.3-, E11.3-, E13.3-)
• Endocrine, nutritional and metabolic diseases (E00-E88)
• Injury (trauma) of eye and orbit (S05.-)
• Injury, poisoning and certain other consequences of external causes (S00-T88)
• Neoplasms (C00-D49)
• Symptoms, signs and abnormal clinical and laboratory findings (R00-R94)
• Syphilis related eye disorders (A50.01, A50.3-, A51.43, A52.71)

Use Additional Code

Use an external cause code following the code for the eye condition, if applicable, to identify the cause of the eye condition.

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MS-DRG Assignment

Inpatient Hospital Grouping

H54.42A4 is grouped within the following Medicare Severity Diagnosis Related Groups (MS-DRG v43.0):

MS-DRG	Description	Relative Weight	Typical LOS
124	Other disorders of the eye with MCC or thrombolytic agent	Varies by year	Varies
125	Other disorders of the eye without MCC	Varies by year	Varies

DRG Assignment Logic

• MS-DRG 124: Assigned when patient has Major Complications/Comorbidities (MCC)
• MS-DRG 125: Assigned when patient has no MCC or only Comorbidities (CC)

Note: H54.42A4 alone does not determine DRG assignment - it depends on the complete clinical picture and presence of MCC/CC conditions.

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HCC Risk Adjustment Status

CMS-HCC Model Information

H54.42A4 falls under the CMS-HCC risk adjustment model used for Medicare Advantage payment calculations

2026 HCC Model Updates

• CMS is completing the phase-in of the 2024 CMS-HCC model (V28) by using 100% of the risk score in 2026
• The new model expanded HCC categories from 86 to 115
• 2,294 diagnosis codes were removed under the new model

HCC Mapping Considerations

Factor	Status
HCC Category	Requires verification against current HCC mapping
RAF Score Impact	Vision-related HCCs typically contribute to risk adjustment
Documentation	MEAT criteria required (Monitor, Evaluate, Assess/Address, Treat)
Annual Recapture	HCC diagnoses must be documented annually for risk adjustment

Important HCC Notes

1. Chronic Condition: Blindness is considered a chronic condition for HCC purposes
2. Annual Documentation: Must be documented each calendar year to count toward RAF score
3. Specificity: Category-specific codes (like H54.42A4) are preferred over unspecified codes
4. Underlying Cause: The underlying etiology may also map to separate HCC categories

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wRVU and Assistant Payable Information

Important Clarification

H54.42A4 is an ICD-10-CM diagnosis code, not a CPT procedure code. Therefore:

Attribute	Status
wRVU (Work Relative Value Unit)	Not Applicable - Diagnosis codes do not have RVUs
Assistant Payable	Not Applicable - This applies to surgical CPT codes only
Global Period	Not Applicable
Facility/Non-Facility	Not Applicable

Related CPT Codes for Blindness Evaluation

When documenting and managing patients with H54.42A4, the following CPT codes may be relevant:

CPT Code	Description	Typical wRVU
92002/92004	Ophthalmological services (new patient)	0.49/0.96
92012/92014	Ophthalmological services (established)	0.41/0.77
92250	Fundus photography	0.37
92133/92134	OCT imaging	0.37/0.43
92083	Visual field examination	0.49
92283	Color vision testing	0.24

Note: wRVU values are approximate and vary by payer contract and year.

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Coding Examples

Example 1: Diabetic Blindness

Clinical Scenario: Patient with type 2 diabetes presents with left eye blindness (category 4) and normal right eye vision due to proliferative diabetic retinopathy.

Correct Coding: Primary: E11.359 - Type 2 diabetes mellitus with proliferative diabetic retinopathy Secondary: H54.42A4 - Blindness left eye category 4, normal vision right eye

Rationale: The underlying diabetes with retinopathy is coded first per “code first” guidelines.

Example 2: Glaucoma-Related Blindness

Clinical Scenario: Patient with primary open-angle glaucoma resulting in left eye category 4 blindness, right eye normal.

Correct Coding:

Primary: H40.119 - Primary open-angle glaucoma, unspecified eye Secondary: H54.42A4 - Blindness left eye category 4, normal vision right eye

Example 3: Age-Related Macular Degeneration

Clinical Scenario: Patient with advanced dry AMD in left eye causing category 4 blindness, right eye unaffected.

Correct Coding:

Primary: H35.30 - Unspecified macular degeneration Secondary: H54.42A4 - Blindness left eye category 4, normal vision right eye

Example 4: Unspecified Cause (Not Recommended)

Clinical Scenario: Documentation only states “left eye blindness” without visual acuity measurements.

Incorrect Coding: Query provider for specific visual acuity measurements If unavailable: H54.40 - Blindness, one eye, unspecified eye

Example 5: Bilateral Vision Loss (Different Code)

Clinical Scenario: Patient has category 4 blindness in left eye AND category 2 low vision in right eye.

Correct Coding: H54.124 - Blindness left eye category 4, low vision right eye category 2 (NOT H54.42A4 - this code requires NORMAL vision in right eye)

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Common Coding Errors to Avoid

Error 1: Using Unspecified Code When Specificity Available

Incorrect	Correct
H54.42 (non-billable)	H54.42A4 (billable with category)
H54.4 (non-billable)	H54.42A4 (billable with laterality)

Error 2: Wrong Laterality

Documentation	Incorrect Code	Correct Code
Right eye blindness	H54.42A4	H54.414A
Left eye blindness	H54.414A	H54.42A4

Error 3: Wrong Category

Visual Acuity	Incorrect Code	Correct Code
Category 3 (20/500-20/1000)	H54.42A4	H54.42A3
Category 4 (<20/1000-LP)	H54.42A3	H54.42A4
Category 5 (No LP)	H54.42A4	H54.42A5

Error 4: Missing Underlying Cause

Incomplete Coding	Complete Coding
H54.42A4 only	E11.359 + H54.42A4

Error 5: Coding Amaurosis Fugax with H54

Incorrect	Correct
G45.3 + H54.42A4	G45.3 only (Excludes1)

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Documentation Requirements

Essential Elements for H54.42A4

1. Visual Acuity Measurements

   • Left eye: Documented in category 4 range (<20/1000 to light perception)
   • Right eye: Documented as normal (20/20 to 20/60)
   • Specify if measured with correction (glasses/contacts)

2. Laterality

   • Clearly document which eye is affected
   • Avoid ambiguous terms like “one eye” without specification

3. Underlying Etiology

   • Document the cause of blindness
   • Code the underlying condition first

4. Chronicity

   • Indicate if condition is stable, progressing, or improving
   • Important for HCC risk adjustment

5. Functional Impact

   • Document impact on daily activities
   • May support medical necessity for services

MEAT Criteria for HCC

For risk adjustment purposes, ensure documentation includes:

• Monitor: Evidence the condition is being monitored
• Evaluate: Assessment of the condition’s status
• Assess/Address: Clinical decision-making related to the condition
• Treat: Treatment plan or management of the condition

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Clinical Considerations

Legal Blindness Definition

In the United States, legal blindness is defined as:

• Central visual acuity of 20/200 or less in the better-seeing eye with best correction, OR
• Visual field of 20 degrees or less in the better-seeing eye

Note: H54.42A4 represents unilateral blindness with normal vision in the other eye, which does NOT meet the federal definition of legal blindness (which requires the BETTER eye to be 20/200 or worse).

Social Security Administration Criteria

For disability determination, SSA defines blindness as:

• Central visual acuity of 20/200 or less in the better eye with corrective lens
• Visual field limitation of 20 degrees or less in the better eye

Functional Implications

Patients with unilateral category 4 blindness:

• May have difficulty with depth perception
• Reduced peripheral vision on affected side
• May qualify for vocational rehabilitation services
• May need driving evaluation (state-specific requirements)

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Quality Measures & Reporting

Potential Quality Measure Impact

H54.42A4 may impact the following quality reporting programs:

Program	Relevance
MIPS (Merit-based Incentive Payment System)	May affect quality measures related to eye care
Medicare Advantage Star Ratings	Vision care measures may apply
HEDIS Measures	Eye exam measures for diabetic patients

Registry Reporting

Consider reporting to:

• IRIS Registry (Intelligent Research in Sight)
• AAO Preferred Practice Pattern compliance
• State blindness registries (if applicable)

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Code History & Changes

Year	Effective Date	Status	Notes
2018	10/1/2017	New Code	Initially implemented
2019	10/1/2018	No Change	Maintained
2020	10/1/2019	No Change	Maintained
2021	10/1/2020	No Change	Maintained
2022	10/1/2021	No Change	Maintained
2023	10/1/2022	No Change	Maintained
2024	10/1/2023	No Change	Maintained
2025	10/1/2024	No Change	Maintained
2026	10/1/2025	No Change	Current version

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Related Resources

ICD-10-CM Code Ranges

Range	Description
H00-H59	Diseases of the Eye and Adnexa
H53-H54	Visual Disturbances and Blindness
H54	Blindness and Low Vision
H54.0	Blindness, both eyes
H54.1	Blindness, one eye, low vision other eye
H54.2	Low vision, both eyes
H54.3	Unqualified visual loss, both eyes
H54.4	Blindness, one eye
H54.5	Low vision, one eye
H54.6	Unqualified visual loss, one eye
H54.7	Unspecified visual loss

Common Co-occurring Conditions

Condition	ICD-10 Code Range
Diabetic Retinopathy	E08-E13 with .3-
Glaucoma	H40.-
Cataract	H26.-
Macular Degeneration	H35.3-
Retinal Detachment	H33.-
Optic Nerve Disorders	H47.0-
Corneal Opacity	H17.-

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Billing & Reimbursement Notes

Outpatient/Professional Claims

• H54.42A4 is billable on professional claims (CMS-1500)
• Must be supported by medical record documentation
• Link to appropriate CPT codes for services rendered

Inpatient/Facility Claims

• Used on UB-04 claims for facility billing
• Contributes to MS-DRG assignment (124 or 125)
• May affect length of stay and reimbursement

Risk Adjustment Claims

• Document annually for HCC capture
• Ensure MEAT criteria are met
• Submit during appropriate collection period

Denial Prevention

Common denial reasons and prevention:

Denial Reason	Prevention Strategy
Lack of medical necessity	Document functional impact and treatment plan
Insufficient specificity	Use category-specific codes (H54.42A4 vs H54.42)
Missing underlying cause	Code etiology first per guidelines
Duplicate coding	Avoid coding both unspecified and specific codes

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Quick Reference Checklist

Before Submitting H54.42A4

• Visual acuity documented for BOTH eyes
• Left eye acuity falls in category 4 range
• Right eye acuity confirmed as normal
• Underlying cause identified and coded first
• Laterality clearly documented
• No Excludes1 conflicts (G45.3 amaurosis fugax)
• Documentation supports medical necessity
• For HCC: MEAT criteria met and documented annually

Code Selection Decision Tree

Is blindness documented? ├── NO → Consider H53.- (Visual disturbances) └── YES ├── Both eyes affected? │ ├── YES → H54.0- series │ └── NO │ ├── Low vision in other eye? │ │ ├── YES → H54.1- series │ │ └── NO (Normal vision) │ │ ├── Right eye affected? → H54.41-A series │ │ └── Left eye affected? → H54.42-A series │ │ ├── Category 3? → H54.42A3 │ │ ├── Category 4? → H54.42A4 ✓ │ │ └── Category 5? → H54.42A5 │ └── Visual acuity unspecified? │ └── H54.40 (unspecified eye) or H54.42 (left eye) └── Visual acuity not documented? └── Query provider for specificity

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Key Takeaways

1. H54.42A4 is billable and specific - Use instead of parent codes H54.42 or H54.4

2. Code underlying cause first - Per “code first” notation in ICD-10-CM

3. Category 4 = Legal blindness range - Visual acuity <20/1000 to light perception

4. Unilateral with normal other eye - Distinguishes from bilateral blindness codes

5. MS-DRG 124 or 125 - For inpatient admissions depending on MCC presence

6. HCC potential - Document annually with MEAT criteria for risk adjustment

7. No wRVU - This is a diagnosis code, not a procedure code

8. 2026 status: Active - No changes from previous years

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Last Updated: February 28, 2026 Code Set: ICD-10-CM 2026 Effective: October 1, 2025