2021 ICD-10-CM Code H21.309

Idiopathic cysts of iris, ciliary body or anterior chamber, unspecified eye

Version 2021
Billable Code
Unspecified Code
MS-DRG Mapping

Valid for Submission

H21.309 is a billable diagnosis code used to specify a medical diagnosis of idiopathic cysts of iris, ciliary body or anterior chamber, unspecified eye. The code H21.309 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 H21.309 might also be used to specify conditions or terms like cyst of anterior chamber of eye, cyst of ciliary body, cyst of iris, idiopathic cyst of anterior chamber of eye, idiopathic cyst of ciliary body , idiopathic cyst of iris, etc.

Unspecified diagnosis codes like H21.309 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:H21.309
Short Description:Idio cysts of iris, ciliary body or ant chamber, unsp eye
Long Description:Idiopathic cysts of iris, ciliary body or anterior chamber, unspecified eye

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 H21.309 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 H21.309 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code H21.309 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.

Information for Patients


Eye Diseases

Some eye problems are minor and don't last long. But some can lead to a permanent loss of vision.

Common eye problems include

Your best defense is to have regular checkups, because eye diseases do not always have symptoms. Early detection and treatment could prevent vision loss. See an eye care professional right away if you have a sudden change in vision, if everything looks dim, or if you see flashes of light. Other symptoms that need quick attention are pain, double vision, fluid coming from the eye, and inflammation.

NIH: National Eye Institute


[Learn More]

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)