Neuroimaging is a branch of medical imaging which focuses on the brain. In addition to being used to diagnose disease and assess brain health, neuroimaging is also valuable in the study of the brain, how the brain works, and how various activities impact the brain. Many hospitals and research facilities have a neuroimaging department, which in small facilities may be bundled into the general medical imaging department.
The capability to look inside the body with imaging equipment started with the development of X-Ray machines in the early 20th century, and grew by leaps and bounds in the 1960s and 1970s. New imaging technology is constantly being developed, along with new ways to use that technology. The field of neuroimaging has benefited immensely from advances in imaging technology which have allowed companies to develop machines which can probe into the complexities of the brain.
There are two types of neuroimaging: functional and structural. Functional neuroimaging is focused on the functions of the brain, using equipment which can register brain activity. In a classic example of functional neuroimaging, functional Magnetic Resonance Imaging (MRI) can generate images in which different sections of the brain light up as they become active. Structural neuroimaging is static and concerned with the physical structure of the brain. Computed Axial Tomography (CAT), for example, can be used to identify tumors in the brain which could interfere with function.
In addition to MRI and CAT scans, neuroimaging can also use technology like Positron Emission Topography (PET), MagnetoEncephaloGraphy (MEG), diffuse optical imaging, and event related optical imaging. All of this technology can be used in a variety of ways to look at the brain and see how it works, sometimes with the assistance of contrast dyes, physical prompts for the patient, and other tools which will form a more complete picture of the brain.
When a doctor recommends neuroimaging for a patient, it is usually because the doctor is concerned about the patient's brain function, or because he or she wishes to rule out concerns about brain function when determining a diagnosis. The procedures for neuroimaging techniques vary, depending on the type of imaging studies which have been ordered, and patients are usually walked carefully through the process to ensure that the images are of high quality so that the imaging studies do not have to be repeated.
People who participate in studies on the brain may be asked to submit to neuroimaging as part of their participation in the study. This neuroimaging is performed for research purposes, not diagnostic ones, although obviously if a problem is identified, the research participant will be notified.