When a code descriptor states “unilateral or bilateral,” that means the code is inherently bilateral.

Most ophthalmic testing services are inherently bilateral, which means that payment is the same whether one or both eyes are tested. Whether you test one or both eyes, you submit the service once.

Tests with unilateral payment should be submitted with either modifier -RT or -LT. You only bill for the eye that has pathology. Ophthalmology is a specialty that still has tests with unilateral coverage. Examples:

• 76510 Ophthalmic ultrasound, diagnostic; B-scan and quantitative A-scan performed during the same patient encounter
• 76511 Quantitative A-scan only
• 76512 B-scan (with or without superimposed non-quantitative A-scan)
• 76516 Ophthalmic biometry by ultrasound echography, A-scan
• The professional component (26) of 76519 Ophthalmic biometry by ultrasound echography, A-scan with intraocular lens power calculation and 92136 Ophthalmic biometry by partial coherence interferometry with intraocular lens power calculation
• 76519 Ophthalmic ultrasonic foreign body localization

Proper biometry coding for Medicare Part B patients varies by Medicare administrative contractor (MAC). Be sure to confirm requirements before submission. You may also reference the Academy’s biometry fact sheet.

For tests that are payable per eye and pathology is observed in both eyes, practices have two options for claim submission:

• A single line item, append modifier -50
• Two-line items, one with modifier –RT, one with modifier -LT, each with a 1 in each unit field

Payment is 100% of the allowable per eye with no 50% reduction for the second eye for all but Current Procedural Terminology (CPT) code 76516.