Are There Radiation Risks Associated with SPECT or PET Brain Imaging?
Many people believe radiation is harmful at any level and believe any medical imaging procedure using exposure to radiation will increase risk. Medical practice and research expend great efforts (and costs) to minimize radiation exposure for patients, research volunteers, and workers. Some individuals argue fMRI imaging sequences should be used instead of Nuclear Medicine techniques, such as SPECT or PET, in order to avoid the perceived radiation risk of the radioactive tracer techniques. Many times this fear of radiation is fostered by the widespread regulatory use of the “Linear No-Threshold Theory” (described below, in lay language) regarding the assessment of radiation risk. In fact, SPECT and PET brain imaging procedures have no more known risk than MRI-based techniques. Below, we briefly review the data regarding low-level radiation and risk. The “Linear No-Threshold Theory” is a working hypothesis originated in the 1950s to serve as a prudent operational guideline to describe ra
