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H18.502 ICD-10-CM Code: Unspecified hereditary corneal dystrophies, left eye

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Inpatient Payment Groups (MS-DRG)

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0, Appendix B.

  • MS-DRG 124 — OTHER DISORDERS OF THE EYE WITH MCC OR THROMBOLYTIC AGENT (MDC 02)
  • MS-DRG 125 — OTHER DISORDERS OF THE EYE WITHOUT MCC (MDC 02)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Official Registry Overview & Definition

Unspecified hereditary corneal dystrophies, left eye is a billable ICD-10-CM diagnosis code (H18.502).

Change history

  • FY2021 — 2020-10-01
    Added to the code set
    Unspecified hereditary corneal dystrophies, left eye
    FY2021 changes

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.

Contextual Map

Every relationship of H18.502 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.

Hierarchy

  • H00-H59 — Chapter 7: Diseases of the Eye and Adnexa (H00-H59) (H00-H59) [Hierarchy]
  • H15-H22 — Disorders of sclera, cornea, iris and ciliary body [Hierarchy]

Clinical classification (CCSR)

  • EYE001 — Cornea and external disease [CCSR]

Potential MS-DRG

  • 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)”
  • DRG 125 — OTHER DISORDERS OF THE EYE WITHOUT MCC [MS-DRG]: “OTHER DISORDERS OF THE EYE WITHOUT MCC (MDC 02)”

MDC crossing · procedures (1200)

  • 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.”
  • 039S0ZX — Drainage of Right Temporal Artery, Open Approach, Diagnostic [Same-MDC procedure]: “Drainage of Right Temporal Artery, Open Approach, Diagnostic — grouped in MDC 02, the procedure side of this code's crossing.” · check together
  • 039S4ZX — Drainage of Right Temporal Artery, Percutaneous Endoscopic Approach, Diagnostic [Same-MDC procedure]: “Drainage of Right Temporal Artery, Percutaneous Endoscopic Approach, Diagnostic — grouped in MDC 02, the procedure side of this code's crossing.” · check together
  • 039T0ZX — Drainage of Left Temporal Artery, Open Approach, Diagnostic [Same-MDC procedure]: “Drainage of Left Temporal Artery, Open Approach, Diagnostic — grouped in MDC 02, the procedure side of this code's crossing.” · check together
  • 039T4ZX — Drainage of Left Temporal Artery, Percutaneous Endoscopic Approach, Diagnostic [Same-MDC procedure]: “Drainage of Left Temporal Artery, Percutaneous Endoscopic Approach, Diagnostic — grouped in MDC 02, the procedure side of this code's crossing.” · check together
  • 03BS0ZX — Excision of Right Temporal Artery, Open Approach, Diagnostic [Same-MDC procedure]: “Excision of Right Temporal Artery, Open Approach, Diagnostic — grouped in MDC 02, the procedure side of this code's crossing.” · check together
  • and 1195 more

Nearest codes (40)

  • H18 — Other disorders of cornea [Sibling]
  • H18.43 — Other calcerous corneal degeneration [Sibling]
  • H18.44 — Keratomalacia [Sibling]
  • H18.441 — Keratomalacia, right eye [Sibling]
  • H18.442 — Keratomalacia, left eye [Sibling]
  • H18.443 — Keratomalacia, bilateral [Sibling]
  • H18.449 — Keratomalacia, unspecified eye [Sibling]
  • H18.45 — Nodular corneal degeneration [Sibling]
  • and 32 more

Change history

  • FY2021 — Added to the code set [Change history]

Relationships & Classification

Clinical classification (AHRQ CCSR):EYE001 — Cornea and external disease (default).

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

Potential MS-DRG Relationships (FY2026)

Not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity.

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.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to H18.502 in its code family, with their registry titles.

  • H18.469 — Peripheral corneal degeneration, unspecified eye
  • H18.49 — Other corneal degeneration
  • H18.5 — Hereditary corneal dystrophies
  • H18.50 — Unspecified hereditary corneal dystrophies
  • H18.501 — Unspecified hereditary corneal dystrophies, right eye
  • H18.503 — Unspecified hereditary corneal dystrophies, bilateral
  • H18.509 — Unspecified hereditary corneal dystrophies, unspecified eye
  • H18.51 — Endothelial corneal dystrophy
  • H18.511 — Endothelial corneal dystrophy, right eye
  • H18.512 — Endothelial corneal dystrophy, left eye

View all codes in the H18 family