Optometry Coding & Billing Alert

Frequently asked questions about a frequently performed procedure.

Gonioscopy may not be performed as often anymore for glaucoma suspects, especially with the rise of other imaging procedures and technologies, but many optometrists still rely upon it as a diagnostic tool. And coding for it can still be problematic, if you don’t follow CPT® and Medicare rules.

Read on for expert answers to frequently asked questions on CPT® code 92020.

Question: Can I bill a postoperative gonioscopy?

Answer: While some may assume that a gonioscopy is included in the global surgical package, and as such can’t be billed after surgery, the reality is different.

Background: Gonioscopy is a diagnostic test, designed to determine whether glaucoma, if present, is open-angle or closed-angle. CPT® code 92020 describes both indirect and direct procedures. Optometrists use gonioscopy to examine the visually inaccessible anterior chamber angle, the eye’s drainage apparatus (the trabecular network), and its anatomic relation to the adjacent iris. During the more common indirect gonioscopy, the physician uses a mirrored goniolens and biomicroscope to examine the anterior chamber angle opposite the direction of view. The direct method of gonioscopy uses a dome-shaped contact lens to eliminate internally reflected light so the doctor can directly visualize the angle with a gonioscope.

Medicare allows diagnostic tests to be performed in the global period of a previous surgery, especially if the gonioscopy is unrelated to the condition for which the surgery was performed. You should not need to include any special modifiers on the claim, say experts. The documentation of a chief complaint other than the fact that the patient is being seen for postoperative care would have to be noted, or documentation that the fellow eye requires the services would need to be present.

Question: Can I bill gonioscopy bilaterally?

Answer: You can only code 92020 once if the optometrist tests both eyes. Medicare – and many other carriers – consider this procedure inherently bilateral, meaning they pay for the work performed in testing both eyes. Medicare will not apply the usual 150 percent adjustment if you report the code with modifier 50 (Bilateral procedure) or on two lines with modifiers LT (Left side) and RT (Right side) attached.

Unilateral billing: Because the procedure is inherently bilateral, it would be inaccurate to report the full code if the optometrist tests only one eye. In those cases, some payers may require you to append modifier 52 (Reduced services) to CPT® code 92020.

Some practices have a policy to reduce their fees when they need to append a CPT® code with either modifier 52 or 53. Some will continue to charge their usual rates. Reducing rates doesn’t guarantee your claim will be paid. Payers will make that decision and it would be beneficial to you to know your payers’ policies when it comes to modifiers.

“Medicare does direct that the provider should reduce the charge for services reported with the 52 or 53 modifier, based on the percentage of the procedure that was performed,” explains Judith Blaszczyk, RN, CPC, ACS-PM, medical compliance auditor at Auditing for Compliance and Education, Inc. in Overland Park, Kan. “Since fees are typically well over the Medicare fee allowance, the reduction of the charge itself would not impact the payment. The payer will reduce the reimbursement based on their opinion as to how much of the procedure was performed, not based on your fee,” she adds.

Question: Can I report gonioscopy along with an E/M or eye code?

Answer: Gonioscopy is listed as a separate procedure in CPT®. It can’t be billed in addition to a more comprehensive service, such as a routine eye exam. If the gonioscopy is performed routinely, CPT® will bundle the procedure into the eye exam. 

If routine (performed even though the patient doesn’t have a sign, symptom or known diagnosis that it medically warrants), it should not be billed separately. It must also be medically necessary. A screening is not covered, but a gonioscopy is covered, because the patient is a diabetic, for example. Diabetic patients can develop rubeosis iridis (neovascularization of the iris), and gonioscopy is a primary diagnostic technique for this condition. It’s also appropriate to code gonioscopy separately when the optometrist notes that a patient has an anatomically narrow angle, 365.20 (Primary angle-closure glaucoma, unspecified).