Requirements for effective functional breast imaging

Most nuclear medicine physicists were trained on devices aimed at functional neuroimaging. The clinical goals of brain-centered devices differ dramatically from the parameters needed to be useful in the breast clinic. We will discuss similarities and differences that impact on design considerations, and describe our latest generation of positron emission mammography and intraoperative products. Source of physiologic contrast: Clinical neuroimaging depends on flow agents to detect the presence of breaks in the blood-brain barrier. Breast flow agents are nonspecific, and may miss preinvasive lesions. Resolution: Brain cancers are generally diagnosed at late stages, so resolution is not so critical. Detecting early breast cancers, and specifying margins for surgery requires 3 mm spatial resolution or better. Prevalence: Primary brain cancer is uncommon, and lesions mimicking brain cancer are rare. Primary breast cancer is common, and benign lesions are even more common, so specificity and biopsy capability are very important. Anatomic references: Brain structure is standard, while breast structure is highly variable, requiring immobilization/compression for physiologic imaging and biopsy. Surgery: Complete cancer resections for brain are very rare, but are possible for breast with appropriate imaging guidance, implying the need for rapid and reliable imaging.To summarize, the breast clinic needs a rapid and highly sensitive method of assessing breast physiology, compatible with biopsy and surgery. Positron emission mammography devices, in handheld and X-ray platform based configurations, are ideal for this mission.