Get a Closer View of ICD-10-CM Glaucoma Coding
Laterality and stage of condition are key areas
to keep an eye on in physician documentation.
More than 3 million people in the United States suffer from glaucoma. The disease is a leading cause of blindness worldwide. It’s incurable, and vision lost cannot be regained; however, medication and surgical procedures can halt the loss of vision.
Types of Glaucoma
The optic nerve may become damaged due to eye pressure. In the front of the eye is a space called the anterior chamber. A clear fluid flows continuously in and out of the chamber and nourishes nearby tissues. The fluid leaves the chamber at the open angle where the cornea and iris meet. When the fluid reaches the angle, it flows through a sponge-like meshwork that acts as a drain, and then leaves the eye. Glaucoma is classified as closed or open angle.
Closed-angle glaucoma often presents with acute symptoms such as eye pain and blurred vision, and is considered an emergency.
Closed-angle glaucoma is less frequent than open-angle. Poor drainage is caused by the angle between the iris and the cornea becoming too narrow and physically blocked by the iris. This condition leads to a sudden buildup of pressure in the eye.
In open-angle glaucoma, even though the drainage angle is “open,” fluids pass too slowly through the drain and build up, causing pressure in the eyes to rise to a level that damages the optic nerve. Another risk factor for optic nerve damage relates to blood pressure. Not everyone who develops increased eye pressure develops glaucoma; each patient handles the pressure differently.
Primary open-angle glaucoma reduces blood flow and damages the optic nerve. It also causes optic neuropathy — a condition that causes the axons of the optic nerve to die. Primary open-angle glaucoma is more prevalent than open-angle glaucoma, and is considered the leading cause of irreversible blindness in the world. The condition is less common in those under 40 years of age, and more common in those over 70 years of age.
The leading causes of risk include:
- Increased intraocular pressure
- History of fracture
- Family history
- Poor vision
- Certain medications
Primary open-angle glaucoma usually results from decreased outflow of aqueous fluid due to an acceleration and exaggeration of normal aging changes in the anterior chamber angle, iris, and ciliary body tissues of the eye. It generally occurs bilaterally, but it isn’t always symmetrical in the stage progression.
Secondary open-angle glaucoma may result from a variety of substances that mechanically block the outflow of aqueous fluid through the anterior chamber angle.
Glaucoma can develop without increased eye pressure. This is called low-tension or normal-tension glaucoma. It’s a type of open-angle glaucoma. Less common causes of glaucoma include a blunt or chemical injury to the eye, severe eye infection, blockage of blood vessels in the eye, inflammatory conditions of the eye, and eye surgery to correct another condition. The condition can form in both eyes at different stages.
Diagnosis codes for glaucoma include laterality and the stage of the condition. “Unstageable” means the physician is unable to determine the stage, not that the physician did not document the stage. For lack of documentation, use an unspecified code.
Quality Reporting Is Key in 2017
New for 2017, ICD-10-CM adds laterality codes for glaucoma conditions that were previously missing. Coders and clinicians must work together to ensure that all of the required documentation elements are captured to assign the appropriate code. Glaucoma is a measure for the Physician Quality Reporting System and is included in risk adjustment measures. The transition to value-based payment models solidifies the need to correctly document and capture these codes.
Rhonda Buckholtz, CPC, CPMA, CPC-I, CRC, CHPSE, CENTC, COBGC, CPEDC, CGSC, is vice president of strategic development at AAPC.