Thanks Megaspaz!) Like the left turn this is another hand signal that you should know if you have your license. Unlike the left hand turn this one is a little more tricky to figure out if you aren't familiar with it so don't expect your average car driver to know what this means.
A Single Photon Emission Computed Tomography (SPECT) scan is a type of nuclear imaging test that shows how blood flows to tissues and organs. A SPECT scan integrates two technologies to view your body: computed tomography (CT) and a radioactive material (tracer). The tracer is what allows doctors to see how blood flows to tissues and organs.
[edit on Wikidata] A radioallergosorbent test (RAST) is a blood test using radioimmunoassay test to detect specific IgE antibodies, to determine the substances a subject is allergic to. This is different from a skin allergy test, which determines allergy by the reaction of a person's skin to different substances. Because there are other tests that help with confirmation, results are best interpreted by a doctor. Since at least 2010, health organizations have recommended that the RAST be abandoned as a diagnostic test for allergy in favor of more sensitive fluorescence enzyme-labeled assays.