2026 ICD-10-CM Diagnosis Code H21.1X9Other vascular disorders of iris and ciliary body, unspecified eye

ICD-10-CM Codes›H00–H59›H15-H22›H21

ICD-10-CM H21.1X9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

H21.1X9 is a billable ICD-10-CM diagnosis code for other vascular disorders of iris and ciliary body, unspecified eye. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 124 through 125. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified eye disorders.

Code Identity

ICD-10-CM Code
H21.1X9
Billable Status
Yes — Valid for Submission
Code Describes
Other vascular disorders of iris and ciliary body, unspecified eye
Short Description
Other vascular disorders of iris and ciliary body, unsp eye
Parent Code
H21.1X
Other vascular disorders of iris and ciliary body

Code Classification

ChapterH00–H59Diseases of the eye and adnexa
SectionH15-H22Disorders of sclera, cornea, iris and ciliary body
CategoryH21Other disorders of iris and ciliary body
This CodeH21.1X9Other vascular disorders of iris and ciliary body, unspecified eye

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Blood vessels in iris
  • Iris and ciliary body vascular disorder
  • Neovascularization of angle due to central retinal vein occlusion
  • Neovascularization of inferior quadrant of angle
  • Neovascularization of iridocorneal angle
  • Neovascularization of iris due to central retinal vein occlusion
  • Neovascularization of nasal quadrant of angle
  • Neovascularization of superior quadrant of angle
  • Neovascularization of temporal quadrant of angle
  • Proliferative retinopathy with iris neovascularization due to diabetes mellitus
  • Rubeosis iridis
  • Rubeosis iridis due to type 1 diabetes mellitus
  • Rubeosis iridis due to type 2 diabetes mellitus
  • Vascular tufts at pupil margin

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR EYE012
Other specified eye disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

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Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert H21.1X9 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
364.42 Rubeosis iridis
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About H21.1X9Overview

Is H21.1X9 (Other vascular disorders of iris and ciliary body) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other vascular disorders of iris and ciliary body, unspecified eye on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does H21.1X9 group to?

When other vascular disorders of iris and ciliary body, unspecified eye is the principal diagnosis on an inpatient stay, it groups to MS-DRG 124, 125, with relative weights from 0.7678 to 1.3231 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of H21.1X9?

Under the General Equivalence Mappings, other vascular disorders of iris and ciliary body, unspecified eye converts to ICD-9-CM 364.42 (rubeosis iridis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.