BI-RADS (Breast Imaging Reporting and Data System): ACR standardized reporting system for breast imaging; ultrasound categories 0–6 guide clinical management from routine screening to biopsy recommendation.
BI-RADS is the ACR standardized lexicon and reporting system for breast imaging including ultrasound, mammography, and MRI. Ultrasound BI-RADS categories range from 0 (incomplete) to 6 (known malignancy). Key descriptors include mass shape, orientation (parallel vs. anti-parallel), margins, echo pattern, and posterior acoustic features. Category 4 and 5 lesions are recommended for biopsy.