A positron emission tomography (PET) scan is an imaging test that can help reveal the metabolic or biochemical function of your tissues and organs. The PET scan uses a radioactive drug called a tracer to show both typical and atypical metabolic activity.

tome (n.) 1510s, "a single volume of a multi-volume work," from French tome (16c.) or directly from Latin tomus "section of a book, tome," from Greek tomos "volume, section of a book," originally "a section, piece cut off," from temnein "to cut," from PIE root *tem- "to cut." Sense of "a large book" is attested from 1570s. ‘ cite ’