Magnetic Resonance Imaging (MRI) Ofl Volunteers

* INCLUSION CRITERIA: Any subject above the age of 18 who is capable of giving informed consent. This study allows for the enrollment of healthy volunteers as well as volunteers with disease for the purpose of continued technical development in a wide variety of conditions. EXCLUSION CRITERIA: A subject will be excluded if he/she has a contraindication to MR scanning implanted metal clips or wires of the type which may concentrate radiofrequency fields or cause tissue damage from twisting in a magnetic field. Examples include: 1. Aneurysm clip 2. Implanted neural stimulator 3. Implanted cardiac pacemaker or autodefibrillator 4. Cochlear implant 5. Ocular foreign body (e.g., metal shavings) 6. Any implanted device (pumps, infusion devices, etc) 7. Shrapnel injuries 8. All employees/staff supervised by the Principal Investigator or an Associate Investigator are excluded from participation. To assess whether subjects are normal eligible to participate, they will be asked to fill out a NIH RADIS MRI Safety questionnaire. Subjects will be excluded if it is deemed that they have a condition which would preclude their use for study related MRI (e.g. paralyzed hemidiaphragm, morbid obesity, claustrophobia etc.) or present unnecessary risks (e.g. pregnancy, surgery of uncertain type, symptoms of pheochromocystoma or insulinoma, etc.). Lactating women and subjects with hemoglobinopathies, asthma, or renal or hepatic disease will be excluded from studies involving the administration of contrast agents. To assess whether subjects are eligible to participate in a GBCA study, before undergoing a GBCA imaging study, volunteers will be asked whether or not they have received a MRI with contrast at an outside institution within the last 6 months and have their Clinical Center medical records reviewed. To track exposures to intravenous GBCAs, for each subject we are administrating GBCA, we will maintain a database recording any reports of GBCA administration at an outside institution and the running total of GCBA administration at the Clinical Center. Volunteers who have had exposure to intravenous GBCAs within the last 6 months at an outside institution or the Clinical Center, or reached their maximum of 4 GBCA research imaging studies during their study participation on this protocol, will be excluded from having a contrast enhanced MRI, but will not be excluded from the protocol for non-contrasted MRI studies. To ensure volunteers who have renal failure do not undergo a GBCA imaging study, all volunteers who will receive Gadolinium based contrast agents will have a serum Creatinine obtained within one week of the MRI examination. All subjects with a calculated eGFR less than or equal to 60 will be excluded from having a contrast enhanced MRI, but will not be excluded from the protocol for non-contrasted MRI studies.