As the number of people in the US who have diabetes increases, the number of patients with diabetic retinopathy (DR) has also grown. A 2021 study showed that approximately 26% of diabetic patients had DR, equating to 9.60 million people.
Of that number, 1.84 million people had vision-threatening (proliferative) diabetic retinopathy (VTDR). Black and Hispanic patients had a higher prevalence of VTDR, and the prevalence increases with age, which leads to early mortality.1
The complexities of coding diabetic retinopathy
Given the increasing incidence of diabetes and DR in the US, it is incumbent on ODs to provide comprehensive medical eye exams to their diabetic patients annually and more frequent follow-ups to those who show signs of DR.
ODs should also take into consideration health conditions often associated with DR, such as hypertension, nephropathy, cardiovascular disease, and peripheral neuropathy, and educate their patients about the link between these comorbidities and eye health. Reports for those examinations should always be sent to the patient’s primary care physician (PCP) and other relevant medical specialists.
Caring for these patients presents several billing, coding, and documentation challenges for providers to ensure that they are paid appropriately for the care these patients require.
What is required to accurately bill and code for DR?
Documentation requires showing the medical necessity for all patient visits in order for them to be billed to medical insurance.
Considering that the standard of care for annual diabetic exams is dilation with a thorough retinal evaluation by the provider,2 which also requires extra provider time to develop a care plan, review and explain the results to the patient, and report them to their PCP, these visits should be billed to the higher reimbursing medical insurance plans and not to vision plans.
While utilizing retinal photography and optical coherence tomography (OCT) for DR is often appropriate, neither are substitutes for a dilated exam based upon the current standard of care.2 As with any billable ancillary testing, these procedures should be justified with medical necessity, and their interpretation and report should be thoroughly documented.
Providers should also adhere to the frequency of testing guidelines provided in Medicare/CMS Local and National Coverage Determination (LCD and NCD) documents, which may be accessed online. Most commercial insurance carriers will abide by these guidelines.
For a comprehensive review of billing and coding in optometry, check out The Ultimate Guide to Optometry Billing and Coding!
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Commonly Used CPT and ICD-10 Codes for Diabetic Retinopathy
This cheat sheet outlines CPT and ICD-10 codes often used for patients with diabetic retinopathy and their respective definitions.
Proper coding for diabetic exams and ancillary tests
Proper ICD-10 and CPT coding are critical for reimbursement and successful audits.
ICD-10 coding tips
Generally speaking, ICD-10 codes billed should mirror what is documented in the patient record, and conditions addressed should be coded to the highest level of specificity.
For example, if the code E11.3211 (type 2 diabetes mellitus with mild non-proliferative diabetic retinopathy with macular edema, right eye) is documented,3 the record should represent that blot hemorrhages, for example, and macular edema were clinically noted during the retinal exam of the right eye. Furthermore, “unspecified” diagnosis codes should be avoided, as these will most likely result in claim denial.
The fundamental rules for choosing the proper ICD-10 codes are listed below:
- Determine whether the patient has type 1 or type 2 diabetes. If the type of diabetes is unclear, ICD-10 guidelines state that the type 2 (E11) diabetes codes should be used for billing purposes.3
- Determine if the diabetes is controlled or uncontrolled.
- If DR is noted, it should be staged and documented properly as either non-proliferative (mild, moderate, severe) or proliferative. Sources such as the International Clinical Diabetic Retinopathy (ICDR) severity scale or ETDRS may be used to accurately stage the DR or VTDR.4
- Document the eye(s) involved.
- Determine if there are any conditions associated with the DR, such as macular edema, retinal detachment, or neovascular glaucoma.
ICD-10 codes are frequently updated and published annually on October 1. Providers should ensure that electronic medical record (EMR) and other systems used for billing are up to date at all times. To minimize problems with EMR systems choosing the incorrect or an “unspecified” code(s), providers should have a basic knowledge of coding without the EMR’s assistance.
Consider CPT codes
When it comes to billing for the diabetic eye exam, providers have the choice of using either 92xxx or 99xxx codes. Many insurers are increasingly misclassifying the 92xxx ophthalmic codes as “routine” vision exam codes, rather than recognizing them as medically necessary services.
This issue has become more prevalent with the integration of vision care plans into Medicare Advantage programs, and has contributed to provider and patient confusion. For this reason, and to delineate these as medically necessary services, it is recommended that providers use the 99xxx E/M codes for billing diabetes-related visits.
The level of the exam billed should appropriately match the documentation of medical decision-making in the patient record.
Common scenarios in the care of patients with diabetes
Patient 1
- R/V: 6-month follow-up of NPDR (no other reasons for visit)
- Findings indicate: Stability from last visit and no new problems
- CPT: 99213
- Logic: Low Complexity of problems (one chronic stable illness); Low risk of Management
- What if: If progression was noted in the DR, this would elevate the Complexity of problems to Moderate (one chronic illness with progression)
Patient 2
- R/V: Newly diagnosed diabetes with very poor control, blurry vision
- Findings indicate: Severe NPDR and center-involved macular edema with 20/60 vision in both eyes
- CPT: 99214
- Logic: Moderate Complexity of problem (one undiagnosed new problem with uncertain diagnosis) and Moderate risk of management (referral for injection)
- What if: If the acute change is truly sight-threatening, it may even meet the criteria for a 99215 exam
All about ancillary testing
Ancillary testing is an important part of the continuing care of diabetic patients, especially those with DR or VTDR. However, in order to be reimbursed for these tests, they must be medically necessary and performed with an appropriate degree of frequency.
In general, the more advanced the DR is, the more frequently the tests may be billed. As mentioned previously, the CMS LCD and NCD guidelines provide information on both the recommended frequency of testing as well as a list of ICD-10 codes approved for the tests.
Medicare guidelines specify that when choosing between two tests that provide information which is considered (by Medicare) to be the same, such as with retinal photos and OCT, only the test that provides the best information to guide the treatment of the patient should be performed and billed for.
Billing unnecessary tests or billing tests too frequently for the level of disease, could be considered “waste” or “abuse,” which could result in recoupment of payments by insurers.
Moreover, proper EMR documentation for ancillary ophthalmic tests requires specific components. The provider must include a written order in the patient’s record for any billable test, both for the current evaluation and any future examinations.
In addition to recording the test results, the provider is also required to complete a formal interpretation and report for procedures such as OCT, retinal photography, visual field testing, and other billable diagnostics where interpretation is necessary.
5 key takeaways
- Determine the type of diabetes.
- Properly stage and document the level of retinopathy.
- Use the highest specificity ICD-10 code.
- Know testing frequency and coding guidelines.
- Choose the proper CPT codes for the care provided.
In conclusion
Providing medical eyecare for diabetic patients requires understanding the disease process itself as well as the documentation and billing and coding to be properly reimbursed for the care these patients require.
It can be rewarding both professionally and financially when all of these are done properly.
