2021 ICD-10-CM Code H18.40

Unspecified corneal degeneration

Version 2021

Valid for Submission

H18.40 is a billable diagnosis code used to specify a medical diagnosis of unspecified corneal degeneration. The code H18.40 is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.

The ICD-10-CM code H18.40 might also be used to specify conditions or terms like corneal degeneration, corneal epithelial degeneration, corneal stromal degeneration, degeneration of cornea of bilateral eyes, degeneration of cornea of left eye , degeneration of cornea of right eye, etc.

Unspecified diagnosis codes like H18.40 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

ICD-10:H18.40
Short Description:Unspecified corneal degeneration
Long Description:Unspecified corneal degeneration

Code Classification

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code H18.40 are found in the index:

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Convert H18.40 to ICD-9 Code

Information for Patients


Corneal Disorders

Your cornea is the outermost layer of your eye. It is clear and shaped like a dome. The cornea helps to shield the rest of the eye from germs, dust, and other harmful matter. It also helps your eye to focus. If you wear contact lenses, they float on top of your corneas.

Problems with the cornea include

Treatments of corneal disorders include medicines, corneal transplantation, and corneal laser surgery.

NIH: National Eye Institute


[Learn More in MedlinePlus]

Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)