Slowed localized fdg metabolism in the left frontal lobe refers to a decreased level of localized tissue metabolism in the left frontal lobe, which can be seen in epilepsy, cerebral ischemia, and other disorders. Before PET-CT examination, glucose labeled with fluorine-18 will be injected into the patient’s body, and the level of glucose uptake reflects the metabolism of the local tissues, i.e., fdg metabolism. fdg metabolism increases, which indicates that the metabolism of the local tissues is vigorous; fdg metabolism slows down, which indicates that the metabolism level of the local tissues decreases. The slowing down of localized fdg metabolism in the left frontal lobe implies that the metabolic level of localized tissues in the left frontal lobe has decreased, which can be seen in: 1. Epilepsy: slow FDG metabolism, accompanied by convulsions, loss of consciousness, etc., which can be induced by various kinds of stimuli. 2. Cerebral ischemia: FDG slowing is accompanied by dizziness and blackouts. The diagnosis of the above diseases can be clarified with the help of EEG and cranial magnetic resonance imaging (CMRI). It is recommended to consult the doctor as soon as possible for early diagnosis and treatment of localized slowing down of FDG metabolism in the left frontal lobe.