Summary & Overview
CPT 78831: SPECT Multi-Region Single-Day Localization
CPT code 78831 represents a single–day SPECT (single-photon emission computed tomography) nuclear imaging study used to localize tumors, inflammatory processes, or the distribution of radiotracers when at least two distinct areas or separate acquisitions are obtained during one session. This code matters nationally because it captures a specific, higher-complexity imaging scenario that can affect utilization patterns, reimbursement flows, and access to advanced diagnostic imaging across outpatient and hospital settings. Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare.
Readers will find a concise overview of what CPT code 78831 covers, typical clinical indications and settings, and the operational implications for sites that perform SPECT with multi-region or multi-acquisition protocols. The publication outlines payer coverage patterns and benchmarks where available, notes relevant coding and billing considerations, and situates the code within common clinical workflows for nuclear medicine. Data not available in the input is identified explicitly where applicable.
Billing Code Overview
CPT code 78831 describes a single–day SPECT nuclear imaging study performed to localize a tumor, an inflammatory process, or the distribution of a radioactive tracer. The code covers studies in which at least two distinct areas or separate acquisitions are imaged on the same day (for example, pelvis and knees or separate lung ventilation and perfusion acquisitions). Vascular flow and blood pool imaging are included if performed as part of the same session.
Service type: Nuclear medicine diagnostic imaging (SPECT), multi-region or multi-acquisition, single day
Typical site of service: Outpatient imaging centers, hospital radiology/nuclear medicine departments, and ambulatory surgical centers where SPECT-capable gamma camera systems are available.
Clinical & Coding Specifications
Clinical Context
A typical patient is a 58-year-old adult referred from oncology for localization of suspected osseous metastases following rising tumor markers and equivocal planar imaging. The patient arrives at an outpatient nuclear medicine clinic or hospital radiology/nuclear medicine department for a single-day SPECT nuclear imaging study that includes at least two distinct anatomic areas (for example, pelvis and knees) due to multi-site pain and suspected multifocal disease.
Clinical workflow: referring provider orders 78831 with clinical history and relevant ICD-10 diagnoses. The patient is registered and screened for contraindications and recent radiopharmaceutical administration. A radiopharmacist or technologist prepares and administers the appropriate tracer (commonly technetium-99m labeled agent). Vascular flow and blood-pool imaging are performed if indicated. The technologist acquires SPECT images of the specified areas during the same day in separate acquisitions. A nuclear medicine physician reviews the images, performs image interpretation, documents findings, and signs the report. Billing is submitted using 78831 for single-day SPECT imaging of at least two areas, with appropriate modifier(s) appended when required by payer rules or to indicate specific circumstances of service.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 |