Coding corner: Diabetic eye disease

Patients with diabetes require ongoing medical care and monitoring to reduce the risk of complications, such as diabetic retinopathy, and improve outcomes. Clinical interventions go far beyond glycemic control.

Diabetic retinopathy
Diabetic retinopathy is caused by persistent high blood sugar levels that, over time, cause damage to the blood vessels in the retina. The blood vessels can swell, leak or close, which impairs the blood supply to the retina. In advanced cases, abnormal new blood vessels can grow on the retina, a process known as neovascularization, which results in loss of vision.

What should primary care doctors do?
Ensure that your diabetic patients have an annual dilated eye screening exam for diabetic eye diseases to prevent or delay blindness. Also, obtain a copy of the eye exam report from the ophthalmologist or optometrist and include it in the patient’s medical record.

Stages of diabetic eye disease

• Non-proliferative diabetic retinopathy: In this early stage, the blood vessels leak, making the retina swell and resulting in blurred vision
• Swelling of the macula (the central part of the retina) is known as macular edema; it’s the most common reason for vision loss among diabetics.
• Macular ischemia results when the blood supply to the macula is interrupted.
• Stages of NPDR range from mild to severe, with or without macular edema.

• Proliferative diabetic retinopathy: This advanced stage includes neovascularization, where the retina grows new abnormally fragile blood vessels, resulting in loss of vision.
• These new blood vessels often bleed into the vitreous, causing floaters or varying degrees of vision loss.
• The new blood vessels can also cause scar tissue to develop, resulting in problems with the macula and can lead to a detached retina.

Accurate documentation and coding
Health care providers should use the ICD-10-CM code Z13.5 (Encounter for screening for eye and ear disorders) until a definitive diagnosis has been determined by an eye care professional. Once definitively diagnosed, documentation and coding should be to the highest specificity of the disorder.

If primary care doctors receive no communication from the eye care professional but are aware of the presence of diabetic eye disease, they should document and code the condition to the highest specificity known to them. See the chart below for some examples.

**The seventh character is required for subcategories E11.32, E11.33, E11.34, E11.35 and E11.37 to designate laterality.

2018 updates to ICD-CM-10 Official Guidelines for Coding and Reporting

In Chapter 7, “Diseases of the Eye and Adnexa, Disorders of the Globe,” you’ll see a change to H42, Glaucoma in diseases classified elsewhere. The manual deletes the “excludes 2” note for glaucoma in diabetes mellitus and replaces it with an instructional note for appropriate sequencing that follows familiar coding conventions. The new note reads: “Code first glaucoma (in) diabetes mellitus (E08.39, E09.39, E10.39, E11.39, E13.39).”

None of the information included in this article is intended to be legal advice and, as such, it remains the provider’s responsibility to ensure that all coding and documentation are done in accordance with all applicable state and federal laws and regulations.