CPT code 78018 represents a nuclear medicine thyroid scan that uses a radionuclide to assess thyroid gland function, detect nodules, or, in patients with thyroid cancer, evaluate for metastatic disease. This diagnostic imaging procedure is a key tool in endocrinology and oncology for characterizing thyroid pathology and guiding subsequent clinical management. Nationally, thyroid scans influence diagnostic pathways, imaging utilization, and coordination between imaging centers and referring clinicians.

Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of clinical context and the typical settings where the service is delivered, followed by practical benchmarking information where available. The publication covers common payer considerations, expected sites of service, and how this service fits into broader diagnostic workflows. It also outlines what to expect in claims processing and documentation needs tied to nuclear medicine imaging of the thyroid.

This summary is intended for health policy analysts, coding specialists, and practice managers seeking a national-level briefing on CPT code 78018, its clinical purpose, and payer coverage landscape. Data not available in the input is noted where applicable.