How do I tell if a code is defined as unilateral or bilateral

There are some procedures which are defined as unilateral procedures, and some defined as bilateral procedures.  If the procedure is defined as unilateral but performed bilaterally, then the physician is paid 150% of the fee schedule amount when performed on both sides.  If the code is defined as bilateral, there is no additional reimbursement for the second procedure.

Modifier 50 is the code appended to a unilateral service to indicate that the service was performed on both sides.

The first place to look is the CPT® book.  In some cases (but not most) the definition of the CPT® code will say, "one or both."  That tells you that the code is already defined as bilateral, and you should not report it with modifier 50.  There is no additional payment because the relative value units include payment for both.  Some codes say specifically, "Report with modifier 50."  That tells you that the service is defined as unilateral, and if done on both sides of the body, it should be reported with modifier 50.  Expect additional payment.

What if the CPT® book is silent, and does not define the code as unilateral or bilateral?  In that case, the Medicare Physician Fee Schedule Data Base is the place to look.  Each CPT® code in the MPFS has an indicator in the bilateral field.  These indicators are:

0=150% payment adjustment for bilateral procedures does not apply. If procedure is reported with modifier -50 or with modifiers RT and LT, base the payment for the two sides on the lower of: (a) the total actual charge for both sides or (b) 100% of the fee schedule amount for a single code. Example: The fee schedule amount for code XXXXX is $125. The physician reports code XXXXX-LT with an actual charge of $100 and XXXXX-RT with an actual charge of $100. Payment should be based on the fee schedule amount ($125) since it is lower than the total actual charges for the left and right sides ($200).

The bilateral adjustment is inappropriate for codes in this category (a) because of physiology or anatomy, or (b) because the code description specifically states that it is a unilateral procedure and there is an existing code for the bilateral procedure.

1=150% payment adjustment for bilateral procedures applies. If the code is billed with the bilateral modifier or is reported twice on the same day by any other means (e.g., with RT and LT modifiers, or with a 2 in the units field), base the payment for these codes when reported as bilateral procedures on the lower of: (a) the total actual charge for both sides or (b) 150% of the fee schedule amount for a single code. If the code is reported as a bilateral procedure and is reported with other procedure codes on the same day, apply the bilateral adjustment before applying any multiple procedure rules.

2=150% payment adjustment does not apply. RVUs are already based on the procedure being performed as a bilateral procedure. If the procedure is reported with modifier -50 or is reported twice on the same day by any other means (e.g., with RT and LT modifiers or with a 2 in the units field), base the payment for both sides on the lower of (a) the total actual charge by the physician for both sides, or (b) 100% of the fee schedule for a single code. Example: The fee schedule amount for code YYYYY is $125. The physician reports code YYYYY-LT with an actual charge of $100 and YYYYY-RT with an actual charge of $100. Payment should be based on the fee schedule amount ($125) since it is lower than the total actual charges for the left and right sides ($200).

The RVUs are based on a bilateral procedure because (a) the code descriptor specifically states that the procedure is bilateral, (b) the code descriptor states that the procedure may be performed either unilaterally or bilaterally, or (c) the procedure is usually performed as a bilateral procedure. 

3=The usual payment adjustment for bilateral procedures does not apply. If the procedure is reported with modifier -50 or is reported for both sides on the same day by any other means (e.g., with RT and LT modifiers or with a 2 in the units field), base the payment for each side or organ or site of a paired organ on the lower of (a) the actual charge for each side or (b) 100% of the fee schedule amount for each side. If the procedure is reported as a bilateral procedure and with other procedure codes on the same day, determine the fee schedule amount for a bilateral procedure before applying any multiple procedure rules. Services in this category are generally radiology procedures or other diagnostic tests which are not subject to the special payment rules for other bilateral surgeries. 

9=Concept does not apply. 

###

Questions, comments?

If you have questions or comments about this article please contact us.  Comments that provide additional related information may be added here by our Editors.

Latest articles:  (any category)