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ICD-10-CM 2027 diagnosis code

H18.791Other corneal deformities, right eye

✓ Billable / specific

H18.791 is a valid, billable ICD-10-CM code for other corneal deformities, right eye. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About H18.791

H18.791 is the ICD-10-CM diagnosis code for other corneal deformities, right eye. It belongs to category H18 (other disorders of cornea), block H15-H22 (disorders of sclera, cornea, iris and ciliary body) and chapter 7 (diseases of the eye and adnexa). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within H18.79 (other corneal deformities), H18.791 is specifically for other corneal deformities, right eye. Related codes cover left eye (H18.792), bilateral (H18.793) and unspecified eye (H18.799).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 124 (Other Disorders of the Eye with MCC or Thrombolytic Agent, relative weight 1.2471) and DRG 125 (Other Disorders of the Eye without MCC, relative weight 0.7702), in MDC 02 (Diseases and Disorders of the Eye), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 371.70 (corneal deformity, unspecified).

Notes that apply from higher levels

Instructions written at a parent level also apply to H18.791.

› From H18.7 Other and unspecified corneal deformities
Excludes1

Broader instructions also apply from Chapter 7: Diseases of the eye and adnexa.

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

ICD-9-CM equivalent

Converter →
  • 371.70Corneal deformity, unspecifiedapproximate

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about H18.791

Is H18.791 billable?

Yes. H18.791 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can H18.791 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict H18.791 as a principal diagnosis.

Is H18.791 a CC or MCC?

No. H18.791 is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does H18.791 group to?

H18.791 is used in the MS-DRG v44.0 logic for MS-DRG 124 (Other Disorders of the Eye with MCC or Thrombolytic Agent) and MS-DRG 125 (Other Disorders of the Eye without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for H18.791?

The CMS General Equivalence Mappings map H18.791 to ICD-9-CM 371.70.