CPT codes describe medical, surgical, and diagnostic procedures and services in five-digit numerical sequences. These codes are published and copyrighted by the American Medical Association (AMA). They allow for standardized documentation and communication between medical facilities and organizations, as well as between patients, healthcare providers, and insurance companies.
In order to describe the myriad number of different medical services, procedures, and factors accurately, CPT codes are divided into three Categories. Category I CPT codes describe medical, surgical, and diagnostic procedures (for instance, a routine checkup of low complexity is CPT code 99213). Category II CPT codes provide supplemental information to Category I CPT codes. The example used in Course 12 is the code for low-density lipoprotein cholesterol (CPT I code 80061) with a result of less than 100 mg of cholesterol per deciliter (CPT II code 3048F). This test and its result would be coded as 80061-3048F.
Category II CPT codes supply information that streamlines administrative work and tracks the performance of certain tests or procedures. These Category II codes, however, do not always provide important information about the specifics of a procedure, like on which side of the body a surgery took place, or whether a surgery was discontinued due to concern for patient safety.
See Examples of CPT Modifiers
In order to communicate this extremely detailed information in an efficient, standardized way, the AMA created CPT modifiers. CPT modifiers are two-character suffixes that healthcare providers or coders attach to a CPT code to give additional information about the procedure documented. CPT modifiers are always two characters in length. They may consist of two numbers from 21 to 99, two letters, or a mix (alphanumeric). These modifiers are appended to the initial CPT code by a hyphen.
Some examples of common CPT modifiers include:
- -53 (discontinued procedure)
- -59 (distinct procedural service)
- -79 (unrelated procedure or service performed by the same physician during the postoperative procedure).
Some common letter-based modifiers include:
- -LT (denotes a procedure on the left side of the body)
- -RT (denotes the right side of the body),
- -GC (identifies that a service has been performed by residents or students under the guidance of a teaching physician).
If you had to code a partial mastectomy of the left breast, you would use the CPT code 19302 for the procedure, with the modifier –LT to describe on which side of the body the procedure took place. Our code would read 19302-LT. If, however, the procedure had to be stopped because of a concern for the well-being of the patient, you would add another modifier: -53. The new code would read 19302-LT-53. Note that this is a simplified example, and that a procedure as complex as a mastectomy often has numerous additional codes).
Certain CPT modifiers are only used with a particular type of procedure or service. For instance, the modifier –LT used above is only valid when describing a procedure on an appendage or organ paired in the body, such as the lung, kidney, leg, or breast. The modifiers, -21, -24, -25, and -27 are only used for evaluation and management. Also, note that unlike CPT codes and ICD codes, CPT modifiers are not necessarily grouped into related procedures.
