Which of the following corresponds to a distinct procedural service?

The correct answer pertains to the modifier 59, which is used to indicate a distinct procedural service. This modifier allows clinicians and coders to report that a procedure or service was distinct or separate from other services performed on the same day. It helps specify that the procedure done was not part of the usual service or was different enough to be reported independently.

Using modifier 59 is essential in circumstances where multiple procedures are performed, ensuring that each service is appropriately recognized and reimbursed. It plays a crucial role in preventing bundling issues where different but related procedures may be improperly grouped together.

In contrast, the other options represent modifiers with different uses. Modifier 78, for example, is used to indicate a return to the operating room for a related procedure during the post-operative period. Modifiers XE and XS are subsets of the 59 modifier, specifically used to provide more granular distinctions between services, but they are not equivalent to the broader concept of a distinct procedural service. Therefore, the understanding and application of modifier 59 is critical for ensuring accurate coding and proper claims processing in outpatient settings.