PET-CT Scan Method to Monitor Pancreatic B-Cell Loss in Diabetes Mellitus

Inclusion Criteria:

• T1DM patients that are over 18 years of age, have had T1DM for greater than 5 years and show a greater than 80% reduction in C-peptide blood levels following intravenous glucagon injection are eligible to participate in this study.
• Healthy controls that are over 18 years of age, show normal C-peptide blood levels following intravenous glucagon injection, and are age- and sex-matched with one of the T1DM patients included in the study, are eligible to participate in this study.

Exclusion Criteria:

• T1DM patients or healthy controls that are not over 18 years of age are not eligible to participate in this study.
• Pregnant females are not eligible to participate in this study because there is a chance PET/CT scans might be risky for the developing baby. Females physically capable of getting pregnant will be required to get a urine pregnancy test at no cost before each of the PET/CT scans. If the pregnancy test is positive, the T1DM patient or healthy control will be excluded from the study. The consent form describes the risks in detail and the need for women of childbearing age to undergo a pregnancy test.
• Subjects with a history of psychiatric illness, substance abuse history, clinically significant head trauma, active neurological disease, cardiovascular disease, liver disease or renal impairment, claustrophobia ((very upset and afraid of being in a small space) are not eligible for the study. Dr. Ping Wang will use the subjects history, blood chemistry, to identify individuals with cardiovascular disease, liver disease, or renal impairment.
• T1DM patients with C-peptide levels following intravenous glucagon injection that are not reduced greater than 80% are not eligible for the study.
• Healthy volunteers with C-peptide levels following intravenous glucagon injection that are reduced greater than 20% compared to established control values are not eligible for the study.
• To determine if it is safe to do the procedure, T1DM patients and healthy volunteers will be expected to tell the researchers about any radiation exposure the individual may have had (including diagnostic or treatment x-rays), and any history of head injury, kidney or bladder disease, or any other serious medical conditions.
• T1DM patients and healthy volunteers will be expected to tell the researchers if they have surgical clips or metallic prostheses (i.e., replacement body parts, such as a hip joint) or a pacemaker or other pieces of metal in the body (shrapnel, metal filings, etc.).
• Patients with history of alcoholism or significant alcohol consumption will be excluded from the study.
• The consent form will be English, and non-English speakers will therefore be excluded from the study.
• Pregnant women are excluded because 18F-fallypride is a radioactive substance , which will be injected into the patient and could be hazardous to the fetus.