2027 ICD-10-CM Diagnosis Code H34.8121Central retinal vein occlusion, left eye, with retinal neovascularization

ICD-10-CM Codes›H00–H59›H30-H36›H34

ICD-10-CM H34.8121
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

H34.8121 is a billable ICD-10-CM diagnosis code for central retinal vein occlusion, left eye, with retinal neovascularization. The 7th character 1 means with retinal neovascularization. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 123. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 46 closely related codes. Coders also document this condition as neovascularization of left retina. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Retinal and vitreous conditions.

For Medicare Advantage risk adjustment, H34.8121 maps to CMS-HCC Category 298 (Severe Diabetic Eye Disease, Retinal Vein Occlusion, and Vitreous Hemorrhage) under the V28 model, adding a risk factor of about 0.336 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
H34.8121
Billable Status
Yes — Valid for Submission
Code Describes
Central retinal vein occlusion, left eye, with retinal neovascularization
Short Description
Central retinal vein occlusion, left eye, w rtnl neovas
Parent Code
H34.812
Central retinal vein occlusion, left eye

Code Classification

ChapterH00–H59Diseases of the eye and adnexa
SectionH30-H36Disorders of choroid and retina
CategoryH34Retinal vascular occlusions
This CodeH34.8121Central retinal vein occlusion, left eye, with retinal neovascularization

Medicare Risk Adjustment (HCC)Billing

H34.8121 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 298— Severe Diabetic Eye Disease, Retinal Vein Occlusion, and Vitreous Hemorrhage
Payment HCC · PY 2027 one of 180 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.336
community, non-dual, aged · ranges 0.301–0.545 across segments
Hierarchy
Top of its hierarchy
HCC 298 is not superseded by any other condition category
Prior Model (CMS-HCC V24)
Not mapped under V24
this diagnosis newly risk-adjusts under the V28 model
Part D (RxHCC)
Not mapped
H34.8121 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Neovascularization of left retina
  • Retinal neovascularization due to occlusion of central retinal vein of left eye

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to H34.8121: its own notes plus those printed at H34.81, H34, and Chapter 7. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From H34 Retinal vascular occlusions applies to 45 codes

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 7 (H00-H59) Diseases of the eye and adnexa applies to 2,677 codes
  • 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, not elsewhere classified (R00-R94)
  • syphilis related eye disorders (A50.01, A50.3-, A51.43, A52.71)

Notes

General instructions on how these codes are used.

From Chapter 7 (H00-H59) Diseases of the eye and adnexa applies to 2,677 codes
  • Use an external cause code following the code for the eye condition, if applicable, to identify the cause of the eye condition

7th Character

Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.

From H34.81 Central retinal vein occlusion applies to 12 codes
  • One of the following 7th characters is to be assigned to codes in subcategory H34.81 to designate the severity of the occlusion:
Values for category H34.81 Retinal Vein Occlusion Status
  • 0with macular edema
  • 1with retinal neovascularization this code
  • 2stable

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name H34.8121, its category, or a range that includes it.

Excludes2 2

These codes carry an Excludes2 note naming H34.8121: its condition is not part of those codes, and both may be reported when the patient has both.

  • I74 Arterial embolism and thrombosis
    ophthalmic embolism and thrombosis (H34.-) names H34.-, which includes this code
  • I74 Arterial embolism and thrombosis
    retinal embolism and thrombosis (H34.-) names H34.-, which includes this code

Code Also 1

These codes say H34.8121 may also be needed to fully describe the condition. The note gives no sequencing direction.

  • H40.84 Neovascular secondary angle closure glaucoma
    central retinal vein occlusion (H34.81) names H34.81, which includes this code

Clinical ClassificationClinical

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

CCSR EYE005
Retinal and vitreous conditions
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Central Retinal Vein Occlusion

    blockage of the central retinal vein.

Patient EducationClinical

Retinal Disorders

Retinal disorders are conditions that affect the retina, the thin light-sensitive tissue at the back of your eye. The retina senses light and sends signals to your brain so you can see.

The full article covers:

  • What are retinal disorders?
  • What causes retinal disorders?
  • What are common retinal disorders?
  • What are the symptoms of retinal disorders?
  • How are retinal disorders diagnosed?
  • How are retinal disorders treated?
  • Can retinal disorders be prevented?

Read the full article at MedlinePlus

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

Convert H34.8121 to ICD-9-CMHistory

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

ICD-9-CM
362.35 Cent retinal vein occlus
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement H34.8121 replaces the following previously assigned code(s):

  • H34.812 - Central retinal vein occlusion, left eye
FY 2019AddedAdded to the ICD-10-CM code setEffective October 1, 2018.
FY 2020–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About H34.8121Overview

Is H34.8121 (Central retinal vein occlusion, left eye) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report central retinal vein occlusion, left eye, with retinal neovascularization on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What does the 7th character 1 in H34.8121 mean?

The final character 1 means with retinal neovascularization, in this case for the central retinal vein occlusion. It comes from the 7th character list in the CMS Tabular List for this category.

What MS-DRG does H34.8121 group to?

When central retinal vein occlusion, left eye, with retinal neovascularization is the principal diagnosis on an inpatient stay, it groups to MS-DRG 123 (neurological Eye Disorders), which carries a relative weight of 0.8218. Higher weights mean higher Medicare reimbursement.

Is H34.8121 a CC or MCC?

CMS lists H34.8121 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 46 closely related codes in its exclusion list.

Can H34.8121 be reported with G45.3?

Not as a rule. The Excludes1 note at H34, which applies to H34.8121, lists "amaurosis fugax (G45.3)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What HCC is H34.8121?

H34.8121 (central retinal vein occlusion, left eye, with retinal neovascularization) maps to CMS-HCC Category 298 (Severe Diabetic Eye Disease, Retinal Vein Occlusion, and Vitreous Hemorrhage), commonly written as HCC 298, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It does not map to any RxHCC in the Part D prescription drug model.

Does H34.8121 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, H34.8121 adds a risk adjustment factor of about 0.336 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.301 to 0.545 depending on the payment segment). HCC 298 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 298 category page.