Summary & Overview
HCPCS A9521: Technetium tc-99m Exametazime, Diagnostic Dose
HCPCS Level II code A9521 denotes technetium tc-99m exametazime, a diagnostic radiopharmaceutical provided per study dose up to 25 millicuries. The code identifies the radiotracer used in nuclear medicine perfusion and other diagnostic studies and is used on claims to represent the radiopharmaceutical supply associated with imaging procedures. Nationally, accurate coding of radiopharmaceuticals matters for proper clinical documentation, reimbursement, and utilization monitoring.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of billing context for A9521, typical sites of service, and what to expect when this radiopharmaceutical is billed alongside nuclear medicine imaging services. The publication outlines benchmark considerations, payer coverage patterns, and the clinical context for exametazime use, including typical diagnostic indications and care settings.
This summary is intended for coding professionals, revenue cycle staff, and policy analysts seeking a national-level reference on A9521 — covering definitions, payer scope, and the types of information to review when this radiopharmaceutical appears on a claim. Data not available in the input is identified where appropriate in detailed sections.
Billing Code Overview
HCPCS Level II code A9521 describes Technetium tc-99m exametazime, a diagnostic radiopharmaceutical dose of up to 25 millicuries per study. This code represents the supply and use of the radiotracer for nuclear medicine brain perfusion imaging or other diagnostic studies where exametazime is indicated.
Service Type: Diagnostic radiopharmaceutical administration and imaging
Typical Site of Service: Hospital outpatient department, outpatient imaging center, or nuclear medicine facility
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult referred to nuclear medicine for a cerebral perfusion study using Technetium Tc-99m exametazime (A9521) to evaluate cerebral blood flow. Common indications include acute stroke evaluation to distinguish ischemic penumbra from infarcted tissue, assessment of suspected brain death when perfusion imaging is required, evaluation of seizure foci in pre-surgical epilepsy workup, or characterization of perfusion abnormalities in dementia and traumatic brain injury. The clinical workflow includes: ordering provider documents indication and relevant history; nuclear medicine schedules the study and screens for pregnancy or breastfeeding; the radiopharmacy dispenses a single study dose (up to 25 millicuries) of Technetium tc-99m exametazime labeled kit; a technologist administers the radiopharmaceutical intravenously and acquires planar and/or SPECT images per protocol; the interpreting nuclear medicine physician or neuroradiologist reviews images, generates a report with perfusion findings, and sends results to the referring clinician for further management. Typical site of service is an outpatient imaging center or hospital nuclear medicine department. Patient preparation may include explanation of procedure, IV access, and continued monitoring for adverse reaction during and after tracer administration.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 |