What does a CPT code with a fourth digit typically specify?

A CPT code with a fourth digit indeed specifies a specific procedure or service within a broader category. The structure of CPT codes typically consists of five digits, where the first three digits identify a category of related services or procedures. The fourth digit further refines this classification, providing more detailed information about the nature of the service performed. For instance, while the first three digits might categorize procedures related to a certain organ or system, the fourth digit can indicate variations in the procedure, such as different approaches, techniques, or specific anatomical sites. This level of specificity helps healthcare professionals understand the nuances of the services rendered, which is essential for accurate billing, documentation, and data collection.