Question 1

What is ICD-10 code H26.491?

Accepted Answer

H26.491 is the ICD-10-CM diagnosis code for other secondary cataract, right eye. A clouding of the lens in the right eye that developed after eye surgery or injury, of a type not specifically classified elsewhere. H26.491 sits in the ICD-10-CM chapter for diseases of the eye and adnexa (h00-h59), within the section covering disorders of lens (h25-h28).

H26.491 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

Use this code when secondary cataract is confirmed but does not fit other specific secondary cataract categories.

Question 2

Is H26.491 an HCC code?

Accepted Answer

No. H26.491 is a billable ICD-10-CM code but does not map to any payment HCC category under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can still be reported on Medicare Advantage encounter data submissions, but it does not contribute to the beneficiary's Risk Adjustment Factor (RAF) score and therefore does not affect the risk-adjusted capitation payment to the plan. V28 reached 100% phase-in for payment year 2026.

Question 3

Is H26.491 billable?

Accepted Answer

Yes. H26.491 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. H26.491 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Question 4

What is the V28 vs V24 difference for H26.491?

Accepted Answer

H26.491 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither model rewards H26.491 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a payment HCC.

Question 5

What should coders know when reporting H26.491?

Accepted Answer

Use this code when secondary cataract is confirmed but does not fit other specific secondary cataract categories Document the underlying cause (surgery, trauma, etc.) in the medical record for clinical clarity

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H26.491

Is H26.491 an HCC code?

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Open H26.491 in the Interactive Encoder

H26.491 ICD-10-CM Code: Other secondary cataract, right eye

HCC Buddy Code Card

H26.491

Is H26.491 an HCC code?

What This Code Means

Coding Tips

Child Codes

Code Hierarchy

Open H26.491 in the Interactive Encoder