Revenue Cycle Insider

Differentiate open and closed angle glaucoma.

Loosely defined, the term glaucoma encompasses a range of conditions affecting more than 4 million Americans and an estimated 60 million people worldwide. As an ophthalmology coder, you need to understand this complex condition and the treatments available.

In this first part of a two-article series, Revenue Cycle Insider breaks down glaucoma and explores common treatment options to alleviate the symptoms.

Get to Know Open- and Closed-Angle Glaucoma

Glaucoma starts to develop when aqueous humor, which nourishes and supports the structure of the eye, drains slowly or inadequately through the trabecular meshwork to the angle at the junction of the iris and cornea. The insufficient drainage can lead to a rise in intraocular pressure (IOP) and potential damage to the optic nerve. As the optic nerve relays information from the eyes to the brain, glaucoma may cause visual complications or even blindness if left untreated.

Primary open-angle glaucoma (POAG) is the most common type and develops over time, sometimes without noticeable symptoms. POAG occurs when the aqueous humor drains slowly due to faulty mechanisms of the eye, much like a clogged drain. Closed-angle glaucoma occurs when the iris shifts to block the drain angle entirely, resulting in a drainage obstruction and causing an immediate and drastic spike in pressure. Other types of glaucoma exist in less common forms. Glaucoma cannot be cured, but various management options exist to control the disease and minimize the risk of vision loss.

Examine Conservative Treatment Options

For patients with increased IOP, most ophthalmologists will begin treatment with one or more medications (eye drops) intended to reduce pressure by decreasing the amount of aqueous humor produced, to open the drainage angles where fluid is eliminated, or both. Many patients respond well to drops and have no further need for other intervention. However, when medication is ineffective, not tolerated, or a patient is noncompliant with their drop regimen, a surgical procedure may be offered to facilitate the drainage of fluid from the eye.

In the 1960s, the introduction of trabeculotomy revolutionized glaucoma surgery and paved the way for continued advancements. Minimally invasive glaucoma surgery (MIGS) procedures have emerged and grown in popularity in recent years. These procedures involve microincisions, specialized tools, and/or miniscule drainage implants, all of which result in faster healing and better patient comfort, for better outcomes with less risk of ocular complications.

Learn How to Report First-Line Treatments

While it may be appealing to treat a glaucoma patient with a MIGS procedure, several Medicare Administrative Contractors (MACs) and commercial payers have requirements for fail-first of medications and/or laser treatments. To qualify for coverage of a MIGS procedure, the patient must have a documented history of treatments that have not achieved the desired decrease in pressure, thus necessitating surgical intervention.

The most common laser treatment for open-angle glaucoma, 65855 (Trabeculoplasty by laser surgery), known as selective laser trabeculoplasty (SLT), aims a cold laser beam at the trabecular meshwork to stimulate the cells and encourage natural drainage. Argon selective laser (ALT) uses a thermal laser instead of cold, but otherwise performs the same procedure and is billed with the same CPT^® code. The operative note will identify the type of laser.

Code 66761 (Iridotomy/iridectomy by laser surgery (eg, for glaucoma) (per session)) is a different type of laser that targets the iris to create a tiny hole as an alternative avenue for aqueous humor to move through the eye. This procedure treats angle-closure glaucoma and is commonly known as a Yag Peripheral Iridotomy (PI). 

These laser treatments can be performed in an office setting and are considered first-line treatments for various types of glaucoma.

Next month in part 2 of the series, Revenue Cycle Insider will examine MIGS and traditional surgeries, as well as stent and shunt placement procedures.

Christine Killeen, CPC, CPB, COPC, Contributing Writer