Focus on Glaucoma: How to Code for Screenings

Glaucoma, open angle glaucoma, closed angle glaucoma, screening for glaucoma, vision changes

Glaucoma: Hippocrates used this name to describe blindness caused by a glazed-looking pupil. Today, the term refers to a group of eye diseases that affects about 3 million Americans and is among the leading causes of blindness. According to the National Eye Institute, without treatment, glaucoma damages the optic nerve, leading to vision loss and blindness. There are two types of glaucoma: open angle, which is the most common type, and closed angle, which affects far fewer patients.

Learn the Ocular Changes of Glaucoma

At the front of the eye lies the anterior chamber, located between the cornea and the lens, through which a watery fluid called the aqueous humor continuously circulates. The aqueous humor flows out of the anterior chamber at the open angle where the cornea and iris meet, through a spongy, drain-like meshwork called the trabecula. From there, it flows into the canal of Schlemm and out of the eye.

Open angle glaucoma: Most glaucoma patients have the open angle, or chronic, version of this disease, in which the aqueous humor fluid doesn’t flow freely from the eye. One theory as to the etiology, or cause, of this condition is that the trabecular meshwork filter is clogged by microscopic particles that slow the fluid’s movement out of the eye. Ophthalmologists typically treat open angle glaucoma with medications that improve this fluid flow.

Closed angle glaucoma: Also called acute glaucoma, this condition is a medical emergency. With acute closed angle glaucoma, the iris bows forward, blocking the trabecular meshwork at the angles so that fluid can’t flow out at all, much like a rubber stopper would block a kitchen sink. The patient develops excruciating eye pain and without prompt treatment, the patient loses vision. A treatment for closed angle glaucoma is laser iridotomy, using a laser to cut a hole in the iris.

Coding Glaucoma Screenings

Because open-angle glaucoma can be a silent disease without presenting symptoms, screening for the condition is important. Medicare and many commercial third-party payers cover annual glaucoma screenings for people at risk, including those with a family history of glaucoma, diabetics, African Americans older than 50, and Hispanics older than 65.

Choose Diagnosis Codes for Glaucoma Screening

Here’s the ICD-10 primary diagnosis code to use for glaucoma screening:

  • Z13.5, Encounter for screening for eye and ear disorders.

Because Medicare and other payers cover screenings for people at risk, an appropriate secondary diagnosis helps smooth the screening procedure claim’s path:

  • E10-E13 for the appropriate diabetes diagnosis (e.g., E11.3, Type 2 diabetes mellitus with ophthalmic complications)
  • Z82.1, Family history of blindness and visual loss
  • Z83.511, Family history of glaucoma
  • Z15.89, Genetic susceptibility to other disease.

Choosing Procedure Codes for Glaucoma Screening

If the only reason a Medicare patient is being seen by an ophthalmologist is to screen for glaucoma, break out the G codes:

  • G0117, Glaucoma screening for high risk patients furnished by an optometrist or ophthalmologist
  • G0118, Glaucoma screening for high risk patient furnished under the direct supervision of an optometrist or ophthalmologist.

The G codes carry several caveats, however. First, remember that Medicare created these codes for its beneficiaries; you would probably not use these codes for non-Medicare patients. Also, remember that even with Medicare, the patient must meet the criteria noted above for screening.

Most importantly, however, in most cases when a patient is seen for an annual eye exam, glaucoma screening would be part of the workup, rather than the only reason for the patient being seen. This means more often than not, you’d simply report the appropriate evaluation and management (E/M) code, without adding a specific glaucoma screening procedure code. You’d only report the glaucoma screening codes if the screening was the only reason the patient was being seen.

What Do You Think?

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Susan taught health information and healthcare documentation at the community college level for more than 20 years. She has a special love for medical language and terminology. She is passionate about ensuring accurate patient healthcare documentation through education. She has a master's degree in healthcare administration, is a certified healthcare documentation specialist, and serves as immediate past president for the Association for Healthcare Documentation Integrity (AHDI).

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