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H40.42X2

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🧬ICD-10 CM H40.42X2: Glaucoma secondary to eye trauma left eye moderate stage

Code: H40.42X2
Description: Glaucoma secondary to eye trauma, left eye, moderate stage

This code is used when a patient has glaucoma in the left eye that is caused by prior eye trauma, and the glaucoma is documented as moderate stage. It belongs to the family of secondary glaucomas where the underlying cause is a previous injury to the eye.

The seventh character 2 indicates moderate stage. The X is a placeholder to allow the seventh character to be placed in the correct position.

Code structure and hierarchy

ICD‑10‑CM chapter and block

  • Chapter H00 to H59 Diseases of the eye and adnexa
  • Block H40 to H42 Glaucoma

Code family

  • H40 Glaucoma
  • H40.4 Glaucoma secondary to eye trauma
    • H40.41X Glaucoma secondary to eye trauma right eye
    • H40.42X Glaucoma secondary to eye trauma left eye
    • H40.43X Glaucoma secondary to eye trauma bilateral
    • H40.49X Glaucoma secondary to eye trauma unspecified eye

Seventh character for stage

  • 0 stage unspecified
  • 1 mild stage
  • 2 moderate stage
  • 3 severe stage
  • 4 indeterminate stage

So H40.42X2 breaks down as:

  • H40.4 secondary glaucoma due to trauma
  • 2 left eye
  • X placeholder
  • 2 moderate stage

7th Character System

The H40.4 series uses a 7th character to specify glaucoma stage:

Clinical meaning

This diagnosis indicates:

  • Glaucoma type secondary glaucoma
  • Cause prior eye trauma such as blunt trauma, penetrating injury, intraocular foreign body, or surgical trauma
  • Eye left eye
  • Stage moderate stage with structural and functional damage beyond mild but not yet severe

Typical clinical features

  • Elevated intraocular pressure or history of elevated pressure
  • Optic nerve damage consistent with glaucoma
  • Visual field loss consistent with moderate stage
  • History of significant trauma to the left eye

Common trauma mechanisms

  • Blunt ocular trauma
  • Penetrating injury
  • Intraocular foreign body
  • Post surgical trauma or complications

Documentation requirements

To support H40.42X2, documentation should clearly state:

  • Diagnosis glaucoma secondary to trauma
  • Laterality left eye
  • Causality link to prior trauma
  • Stage moderate stage
  • Trauma details when known date, type of injury, mechanism

Key documentation elements

  • Statement that glaucoma is secondary to eye trauma
  • Identification of the left eye as the affected eye
  • Explicit stage moderate
  • Description of visual field loss and optic nerve findings
  • Reference to prior injury such as contusion, laceration, or surgical trauma

Supportive phrases

  • Traumatic glaucoma left eye moderate stage
  • Glaucoma secondary to prior blunt trauma left eye moderate stage
  • Left eye glaucoma due to previous eye injury moderate stage

Includes and excludes

Includes

  • Glaucoma of the left eye that is a direct result of prior eye trauma
  • Traumatic glaucoma left eye moderate stage
  • Secondary glaucoma left eye due to penetrating or blunt trauma with moderate damage

Excludes1

  • Primary open angle glaucoma
  • Secondary glaucoma due to other causes such as uveitis, steroid use, or lens disorders
  • Glaucoma without documented link to trauma
  • Glaucoma of the right eye or both eyes
  • Glaucoma with stage not documented as moderate
  • Absolute glaucoma (H44.51-)
  • Congenital glaucoma (Q15.0)
  • Traumatic glaucoma due to birth injury (P15.3)

Excludes2 (May Co-exist)

  • Conditions originating in perinatal period (P04-P96)
  • Infectious diseases (A00-B99)
  • Pregnancy complications (O00-O9A)
  • Congenital malformations (Q00-Q99)
  • Diabetes-related eye conditions (E09.3-, E10.3-, E11.3-, E13.3-)
  • Endocrine/metabolic diseases (E00-E88)
  • Eye trauma (S05.-)
  • Injury/poisoning (S00-T88)
  • Neoplasms (C00-D49)
  • Symptoms/signs (R00-R94)
  • Syphilis-related eye disorders (A50.01, A50.3-,A51.43, A52.71)

Code Also Instructions

Code also: The underlying inflammatory condition causing the glaucoma (e.g., uveitis, iritis)

If the stage is not documented, a code with stage unspecified should be used instead of H40.42X2.

Relationship to HCC, wRVU, assistant payable, and MS‑DRG

HCC status

  • Glaucoma codes, including H40.42X2, do not map to a payment HCC in standard CMS models.
  • They are clinically important for risk and quality tracking but do not directly increase HCC based risk scores.

wRVU

  • wRVUs apply to CPT and HCPCS procedure codes, not ICD‑10‑CM diagnosis codes.
  • H40.42X2 has no wRVU value by itself.
  • It supports medical necessity for procedures such as visual field testing, optic nerve imaging, and glaucoma surgery.
    • Linked CPT Codes: This diagnosis justifies medical necessity for:
    • 92012-92014: Ophthalmological examinations
    • 92133-92134: Scanning computerized ophthalmic diagnostic imaging
    • 92250: Fundus photography
    • 0191T-0192T: Glaucoma progression analysis
  • Work RVU (wRVU): Determined by CPT procedure codes performed

Assistant payable

  • Assistant at surgery rules apply to CPT procedure codes, not diagnosis codes.
  • H40.42X2 is not assistant payable or non payable; it simply supports the clinical context.

MS‑DRG

  • As a diagnosis code, H40.42X2 may appear as a secondary diagnosis in inpatient claims.
  • It typically does not drive MS‑DRG assignment and is not a CC or MCC.
  • It can still help describe the complexity of the patient, especially in ophthalmic or trauma related admissions.

Coding guidance and tips

  • Ensure documentation clearly states that glaucoma is secondary to eye trauma.
  • If the provider only documents glaucoma without linking it to trauma, a primary glaucoma code is more appropriate.
  • If trauma is suspected but not documented as the cause, consider a query.

2. Capture laterality correctly

  • H40.42X2 is left eye only.
  • For right eye, bilateral, or unspecified eye, use the corresponding code in the H40.4 family.
  • Do not assume laterality from prior notes without clear current documentation.

3. Stage must be documented

  • The seventh character 2 requires moderate stage documentation.
  • If the provider does not specify stage, use the stage unspecified option rather than H40.42X2.
  • Encourage providers to document stage based on visual field and optic nerve findings.

4. Use additional codes for trauma

  • Add codes for the original eye trauma when appropriate, especially if the trauma is still clinically relevant.
  • For older injuries, consider sequela codes to show that glaucoma is a consequence of prior trauma.

Code tree for H40.42X series

  • H40.42X0 Glaucoma secondary to eye trauma left eye stage unspecified
  • H40.42X1 Glaucoma secondary to eye trauma left eye mild stage
  • H40.42X2 Glaucoma secondary to eye trauma left eye moderate stage
  • H40.42X3 Glaucoma secondary to eye trauma left eye severe stage
  • H40.42X4 Glaucoma secondary to eye trauma left eye indeterminate stage

This helps you keep your Obsidian vault consistent when you build notes for the other stages.

Coding examples

Example 1 - Blunt trauma with moderate glaucoma

Documentation snippet
Patient with history of blunt trauma to the left eye from sports injury. Now has traumatic glaucoma left eye with moderate visual field loss and optic nerve cupping. Right eye normal.

Coding

  • H40.42X2 glaucoma secondary to eye trauma left eye moderate stage
  • Code for prior blunt trauma or sequela if still clinically relevant

Example 2 - Post surgical trauma

Documentation snippet
Patient developed glaucoma in the left eye after complicated intraocular surgery several years ago. Current exam shows moderate stage traumatic glaucoma left eye.

Coding

  • H40.42X2
  • Code for surgical complication or sequela if documented

Example 3 - Trauma history with clear staging

Documentation snippet
Left eye traumatic glaucoma from prior penetrating injury. Visual field testing shows moderate loss. Right eye unaffected.

Coding

  • H40.42X2
  • Code for sequela of penetrating eye injury

Coding Examples

  • Scenario: 45-year-old patient with chronic anterior uveitis presents with elevated IOP (28 mmHg) in left eye. Optic nerve shows 0.7 cup-to-disc ratio with moderate field loss.
  • ICD-10-CM Codes:
    1. H40.42X2 - Glaucoma secondary to eye inflammation, left eye, moderate stage
    2. H20.012 - Chronic iridocyclitis, left eye
  • CPT Code: 92014 - Ophthalmological examination, established patient

Example 2: Post-Surgical Inflammation

  • Scenario: Patient develops glaucoma 3 months after cataract surgery in left eye, with persistent inflammation and IOP of 30 mmHg.
  • ICD-10-CM Codes:
    1. H40.42X2 - Glaucoma secondary to eye inflammation, left eye, moderate stage
    2. H59.031 - Postprocedural hemorrhage and hematoma of left eye and adnexa following cataract surgery
  • CPT Code: 92012 - Ophthalmological examination, established patient
  • Scenario: Patient with rheumatoid arthritis presents with bilateral uveitis, left eye shows moderate glaucoma (IOP 32 mmHg).
  • ICD-10-CM Codes:
    1. H40.42X2 - Glaucoma secondary to eye inflammation, left eye, moderate stage
    2. H20.033 - Iridocyclitis, bilateral
    3. M05.79 - Rheumatoid arthritis with rheumatoid factor without organ/system involvement
  • CPT Code: 92014 - Ophthalmological examination, established patient

Documentation Guidelines

Critical Elements for Proper Coding:

  1. Specify affected eye (laterality)
  2. Document glaucoma stage (mild, moderate, severe)
  3. Identify underlying inflammatory condition
  4. Include IOP measurements and optic nerve findings
  5. Record visual field test results when available

Common Documentation Errors to Avoid:

  • Using unspecified codes when staging information is available
  • Failing to link the glaucoma to its inflammatory cause
  • Omitting laterality specification
  • Not documenting specific measurements supporting stage assignment

Clinical Management Considerations

  • Treatment: Typically involves anti-inflammatory medications combined with glaucoma management
  • Monitoring: Regular IOP checks, optic nerve assessments, and visual field testing
  • Surgical Options: May require glaucoma drainage devices or trabeculectomy if medical management fails

Code History

  • 2016: Original ICD-10-CM implementation
  • 2016-2025: No significant changes to code structure
  • Current: Valid through 2025 edition

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