This expanded access protocol is proposed to allow University of California San Francisco (UCSF) patients additional access to 18F-fluorocholine (FCH) Positron Emission Tomography (PET) imaging for localization of parathyroid adenomas.

No health outcome measures will be obtained under this protocol.

Inclusion Criteria:

1. Age ≥ 13 years.
2. Evidence of primary hyperparathyroidism.
3. Ability to understand a written informed consent document, and the willingness to sign it.

Exclusion Criteria:

1. Unlikely to comply with protocol procedures, restrictions and requirements and judged by the Investigator to be unsuitable for participation.