The primary aim of this study is to determine if anti-3-[18F]FACBC PET-CT demonstrates uptake within parathyroid adenomas. 12 patients with a diagnosis of primary hyperparathyroidism will undergo PET-CT using anti-3-[18F]FACBC in addition to the standard 99mTc sestamibi scanning and other imaging as clinically appropriate such as ultrasound, MRI, and/or contrast enhanced CT scanning. Since all these patients undergo surgery routinely, the investigators will then compare findings at surgery to those of the anti-3-[18F]FACBC PET-CT to determine if this radiotracer is worthy of further study in a more comprehensive experiment.