Summary & Overview
HCPCS A9541: Technetium Tc-99m Sulfur Colloid, Diagnostic, Up to 20 mCi
HCPCS Level II code A9541 denotes technetium tc-99m sulfur colloid supplied for diagnostic use, per study dose up to 20 millicuries. This radiopharmaceutical is central to certain nuclear medicine procedures — for example, hepatic-splenic imaging and lymphoscintigraphy — where a colloid-based tracer delineates organ structure and function. Nationally, accurate coding of radiopharmaceuticals affects both clinical workflow and billing consistency for facilities performing diagnostic nuclear medicine.
Key payers addressed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of clinical context and common sites of service, plus information relevant to billing workflows: standard code description, common modifiers list (provided separately), and areas where policy and coverage considerations commonly arise for radiopharmaceuticals.
This publication provides benchmarks and policy-focused updates relevant to payers and facilities, explains clinical indications tied to the reagent, and outlines typical billing and site-of-service scenarios. Data not available in the input is noted where applicable. The content is intended for revenue cycle leaders, nuclear medicine departments, and policy analysts seeking a national-level reference on coding and clinical use of technetium tc-99m sulfur colloid under HCPCS Level II code A9541.
Billing Code Overview
HCPCS Level II code A9541 represents technetium tc-99m sulfur colloid, diagnostic, per study dose, up to 20 millicuries. This radiopharmaceutical is used for diagnostic nuclear medicine studies that require a sulfur colloid radiotracer, typically for imaging of the liver, spleen, or lymphatic system.
Service type: Diagnostic radiopharmaceutical administration for nuclear medicine imaging.
Typical site of service: Hospital outpatient department, hospital inpatient nuclear medicine, or freestanding radiology/nuclear medicine centers that perform diagnostic imaging studies.
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult referred for a hepatic or splenic scintigraphy study to evaluate focal liver lesions, suspected splenic accessory tissue, or to assist in localization of a bleeding source. The patient arrives to the nuclear medicine department, registration and allergy review are completed, and informed consent for radiopharmaceutical administration is obtained as required by facility policy. A nuclear medicine technologist prepares A9541 (Technetium Tc-99m sulfur colloid) in the pharmacy or hot lab, confirming dose up to 20 mCi and patient identity. The radiopharmaceutical is administered intravenously; planar and/or SPECT images are acquired per protocol 15–120 minutes post-injection depending on the study. A interpreting physician (nuclear medicine or radiology) reviews images and issues a diagnostic report. Typical workflow includes dose documentation (lot number, activity, route), image acquisition, image processing, and final interpretation. Common clinical indications include characterization of focal hepatic lesions, confirmation of reticuloendothelial function, detection of splenic tissue, evaluation of colloid shift in diffuse liver disease, and localization of gastrointestinal bleeding with adjunctive studies. The typical site of service is an outpatient or hospital-based nuclear medicine / radiology department or an ambulatory imaging center.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component |