All patients received both a Hand Held (HH) and Automated Breast Volume Scanner (ABVS) ultrasound. Patients were initially randomized to have either a HH or an ABVS. The HH ultrasound was performed by one of 4 sonographers that had a minimum of 10 years experience in breast ultrasound. A different sonographer than the one performing the HH or mammography technician performed ABVS. All technologists performing ABVS participated in a training course on ABVS and performed at least 10 patients satisfactorily before beginning the study. The choice of a mammography technician or sonography to perform the ABVS was randomized. Both the sonographer performing the HH and the sonographer or mammography technologist performing the ABVS were provided the patient's history and results of the mammogram if performed for placement of the ABVS and region of interest for the HH. However the results of the HH or ABVS were not available to the person performing the second examination.