General Surgery Coding Alert

Question: I’m new to coding and am having trouble understanding when to use modifiers that describe laterality. Do I use them every time a procedure involves an anatomic structure that can be considered right/left?

Oklahoma Subscriber

Answer: Some CPT^® code descriptors include language about laterality, but other codes do not, and thus may require a modifier.

Laterality modifiers are used in procedure coding to indicate that a procedure or service was performed on the left, the right, or bilateral sides of the body. These modifiers are typically used with CPT^® codes that are specific to one side of the body but not the other.

There are also laterality modifiers for diagnosis codes in the ICD-10-CM coding system, where additional characters describe laterality for some diagnoses or medical conditions.

Here are some procedure situations where a laterality modifier might be required:

• Procedures performed on the eyes or ears, which are clearly left or right
• Procedures performed on limbs, such as arms or legs
• Procedures performed on organs that exist on both sides of the body, like kidneys or lungs

The specific laterality modifiers are RT (Right side (used to identify procedures performed on the right side of the body)), LT (Left side (used to identify procedures performed on the left side of the body)), and 50 (Bilateral Procedure).

Remember, not all procedures require a laterality modifier. For example, code 27395 (Lengthening of hamstring tendon; multiple tendons, bilateral) includes laterality in the description.

Always check the specific CPT^® code description and any guidelines from the payer, as well as the AMA.

Rachel Dorrell, MA, MS, CPC-A, CPPM, Production Editor, AAPC