ICD-10-CM Code H40.9

Unspecified glaucoma

Version 2020 Billable Code

Valid for Submission

H40.9 is a billable code used to specify a medical diagnosis of unspecified glaucoma. The code is valid for the year 2020 for the submission of HIPAA-covered transactions. The ICD-10-CM code H40.9 might also be used to specify conditions or terms like bilateral glaucoma, glaucoma, glaucoma due to type 2 diabetes mellitus, glaucoma following surgery, glaucoma in endocrine, nutritional and metabolic diseases, glaucoma of left eye, etc

Short Description:Unspecified glaucoma
Long Description:Unspecified glaucoma

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 H40.9 are found in the index:


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

  • Bilateral glaucoma
  • Glaucoma
  • Glaucoma due to type 2 diabetes mellitus
  • Glaucoma following surgery
  • Glaucoma in endocrine, nutritional and metabolic diseases
  • Glaucoma of left eye
  • Glaucoma of right eye
  • Iatrogenic glaucoma

Clinical Information

  • GLAUCOMA-. an ocular disease occurring in many forms having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. the consequences of the increased pressure may be manifested in a variety of symptoms depending upon type and severity such as excavation of the optic disk hardness of the eyeball corneal anesthesia reduced visual acuity seeing of colored halos around lights disturbed dark adaptation visual field defects and headaches. dictionary of visual science 4th ed
  • GLAUCOMA OPEN ANGLE-. glaucoma in which the angle of the anterior chamber is open and the trabecular meshwork does not encroach on the base of the iris.
  • OCULAR HYPERTENSION-. a condition in which the intraocular pressure is elevated above normal and which may lead to glaucoma.
  • GLAUCOMA NEOVASCULAR-. a form of secondary glaucoma which develops as a consequence of another ocular disease and is attributed to the forming of new vessels in the angle of the anterior chamber.
  • GLAUCOMA ANGLE CLOSURE-. a form of glaucoma in which the intraocular pressure increases because the angle of the anterior chamber is blocked and the aqueous humor cannot drain from the anterior chamber.
  • EXFOLIATION SYNDROME-. the deposition of flaky translucent fibrillar material most conspicuous on the anterior lens capsule and pupillary margin but also in both surfaces of the iris the zonules trabecular meshwork ciliary body corneal endothelium and orbital blood vessels. it sometimes forms a membrane on the anterior iris surface. exfoliation refers to the shedding of pigment by the iris. newell ophthalmology 7th ed p380
  • GLAUCOMA DRAINAGE IMPLANTS-. devices usually incorporating unidirectional valves which are surgically inserted in the sclera to maintain normal intraocular pressure.
  • WEILL MARCHESANI SYNDROME-. rare congenital disorder of connective tissue characterized by brachydactyly joint stiffness childhood onset of ocular abnormalities e.g. microspherophakia ectopia lentis; glaucoma and proportionate short stature. cardiovascular anomalies are occasionally seen.
  • LOW TENSION GLAUCOMA-. a form of glaucoma in which chronic optic nerve damage and loss of vision normally attributable to buildup of intraocular pressure occurs despite prevailing conditions of normal intraocular pressure.

Diagnostic Related Groups

The ICD-10 code H40.9 is grouped in the following groups for version MS-DRG V37.0 What are Diagnostic Related Groups?
The Diagnostic Related Groups (DRGs) are a patient classification scheme which provides a means of relating the type of patients a hospital treats. The DRGs divides all possible principal diagnoses into mutually exclusive principal diagnosis areas referred to as Major Diagnostic Categories (MDC).
applicable from 10/01/2020 through 09/30/2020.


Convert H40.9 to ICD-9

Code Classification

Code History

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

Information for Patients


Glaucoma is a group of diseases that can damage the eye's optic nerve. It is a leading cause of blindness in the United States. It usually happens when the fluid pressure inside the eyes slowly rises, damaging the optic nerve. Often there are no symptoms at first. Without treatment, people with glaucoma will slowly lose their peripheral, or side vision. They seem to be looking through a tunnel. Over time, straight-ahead vision may decrease until no vision remains.

A comprehensive eye exam can tell if you have glaucoma. People at risk should get eye exams at least every two years. They include

  • African Americans over age 40
  • People over age 60, especially Mexican Americans
  • People with a family history of glaucoma

There is no cure, but glaucoma can usually be controlled. Early treatment can help protect your eyes against vision loss. Treatments usually include prescription eyedrops and/or surgery.

NIH: National Eye Institute

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