Inclusion Criteria:

• All subjects will be over the age of 21.
• Must have symptoms suggestive of a neurodegenerative and/or related disorder;  i.e., patients must have one or more neurological symptom that is insidious in onset and has worsened over time in nature.

Exclusion Criteria:

• Subjects will be excluded if they have any concurrent illnesses that could account for all of their symptoms, such as traumatic brain injury, encephalitis, strokes or developmental syndromes.
• Women that are pregnant or post-partum and breast-feeding will be excluded.
• All women who can become pregnant must have a pregnancy test before the PET/CT scan.
• Subjects will be excluded if they have any of the following genetic conditions which can increase the chance of cancer:
  • Cowden disease;
  • Lynch syndrome;
  • Hypogammaglobulinemia;
  • Wiskott-Aldrich syndrome;
  • Down’s syndrome.
• Subjects will be excluded from undergoing the MRI if it is contraindicated (metal in head, cardiac pace maker, etc), if there is severe claustrophobia, if there are conditions that may confound brain imaging studies (e.g., structural abnormalities, including subdural hematoma, intracranial neoplasm or large cortical infarcts), or if they are medically unstable or are on medications that might affect brain structure or metabolism (e.g., chemotherapy).