Patient case (clinical description): A 19-year-old girl comes to the clinic due to a left wrist mass.  She noticed swelling on the top of her wrist about 4 months ago and came to the clinic due to cosmetic concerns.  Examination shows a nontender, rounded mass on the dorsal wrist that transilluminates with a penlight. Vital signs are normal. The patient needs to type on her computer almost all day. She is left-handed. She does not smoke or use illicit drugs. She is in sexual relationship with two male partners and uses condoms.

Patient's own account: I'm a 19-year-old girl and I went to see my doctor because of a mass on my left wrist. I noticed a swelling on top of my wrist, like 4 months ago, and I went the first time to the doctor because it was pretty ugly! My wrist was not tender, and the mass was round and let the light go through when the doctor used a penlight. My blood pressure, breathing and temperature were normal. I'm left-handed and I need to be on my PC all day. I don't smoke or do drugs. I'm sexually active and I have 2 male partners but they all use condoms.

Clinical trial: Test-retest Reproducibility of [11C]PHNO PET Using the Constant Infusion Paradigm

Eligibility criteria:
Inclusion Criteria:

          -  men and women, aged 18-55 years

          -  who are able to read and write

          -  who are able to give voluntary written informed consent

          -  have no current uncontrolled medical condition such as neurological, cardiovascular,
             endocrine, renal, liver, or thyroid pathology

          -  have no history of a neurological or psychiatric disorder, e.g., no DSMIV Axis 1
             diagnosis in 2 preceding years, except nicotine dependence in smokers)

          -  drink less than 21 drinks/week for women and less than 35 drinks per week for men

          -  have not used marijuana in the past 30 days and have not met criteria for dependence
             in the past 2 years

          -  do not suffer from claustrophobia or any MRI contradictions

          -  nonsmokers (smoked < 40 cigarettes in lifetime with urinary cotinine levels 0-30 ng/mL
             both at intake evaluation and on scan day)

          -  smokers (smoked at least 10 cigarettes/day for at least one year with an FTND>3, urine
             cotinine >150 ng/mL and CO >12 ppm at intake)

        Exclusion Criteria:

          -  psychosis

          -  presence of acute or unstable medical or neurological illness. Subjects will be
             excluded from the study if they present with any history of serious medical or
             neurological illness or if they show signs of a major medical or neurological illness
             on examination or lab testing including history of seizures, head injury, brain tumor,
             heart, liver or kidney disease, eating disorder, diabetes.

          -  regular use of any psychotropic drugs including anxiolytics and antidepressants and
             other over-the-counter medications and herbal products within the last six months

          -  pregnancy/breast feeding (as documented by pregnancy testing at screening or on days
             of the imaging studies),

          -  suicidal ideation or behavior

          -  pacemaker or other ferromagnetic material in body.

          -  use of medications which affect dopamine transmission within 2 weeks of the PET study

          -  participation in other research studies involving ionizing radiation within one year
             of the PET scans that would cause the subject to exceed the yearly dose limits for
             normal volunteers
No condition on gender to be admitted to the trial.
Accepts Healthy Volunteers
Subject must be at least 18 Years old.
Subject must be at most 55 Years

Eligibility (NLI label): Entailment