Message definition (Medicine ) ==== Diagnostic specialties ==== * ''[[Clinical laboratory]] sciences'' are the clinical diagnostic services that apply laboratory techniques to diagnosis and management of patients. In the United States, these services are supervised by a pathologist. The personnel that work in these [[medical laboratory]] departments are technically trained staff who do not hold medical degrees, but who usually hold an undergraduate [[medical technology]] degree, who actually perform the [[medical test|tests]], [[assay]]s, and procedures needed for providing the specific services. Subspecialties include [[transfusion medicine]], [[cellular pathology]], [[clinical chemistry]], [[hematology]], [[clinical microbiology]] and [[clinical immunology]]. * ''[[Pathology as a medical specialty]]'' is the branch of medicine that deals with the study of diseases and the morphologic, physiologic changes produced by them. As a diagnostic specialty, pathology can be considered the basis of modern scientific medical knowledge and plays a large role in [[evidence-based medicine]]. Many modern molecular tests such as [[flow cytometry]], [[polymerase chain reaction]] (PCR), [[immunohistochemistry]], [[cytogenetics]], gene rearrangements studies and [[fluorescent in situ hybridization]] (FISH) fall within the territory of pathology. * ''Diagnostic [[radiology]]'' is concerned with imaging of the body, e.g. by [[x-ray]]s, x-ray [[computed tomography]], [[ultrasonography]], and [[nuclear magnetic resonance]] [[tomography]]. Interventional radiologists can access areas in the body under imaging for an intervention or diagnostic sampling. * ''[[Nuclear medicine]]'' is concerned with studying human organ systems by administering radiolabelled substances (radiopharmaceuticals) to the body, which can then be imaged outside the body by a [[gamma camera]] or a PET scanner. Each radiopharmaceutical consists of two parts: a tracer that is specific for the function under study (e.g., neurotransmitter pathway, metabolic pathway, blood flow, or other), and a radionuclide (usually either a gamma-emitter or a positron emitter). There is a degree of overlap between nuclear medicine and radiology, as evidenced by the emergence of combined devices such as the PET/CT scanner. * ''[[Clinical neurophysiology]]'' is concerned with testing the physiology or function of the central and peripheral aspects of the nervous system. These kinds of tests can be divided into recordings of: (1) spontaneous or continuously running electrical activity, or (2) stimulus evoked responses. Subspecialties include [[electroencephalography]], [[electromyography]], [[evoked potential]], [[nerve conduction study]] and [[polysomnography]]. Sometimes these tests are performed by techs without a medical degree, but the interpretation of these tests is done by a medical professional.