Abstract
Positron emission tomography with 18F-fluorodeoxyglucose (FDG-PET) is useful for the diagnosis of head and neck cancers. We report 5 cases of abnormal FDG uptake in the contralateral larynx of patients with unilateral laryngeal palsy due to lung cancer, lung metastasis of breast cancer, lung metastasis of mesopharyngeal cancer, idiopathic cause and laryngeal cancer after complete remission. We concluded that overactivity of the laryngeal muscles that compensated for the paralyzed vocal cord caused a false-positive PET finding with abnormal uptake of FDG in the contralateral larynx of patients with unilateral laryngeal palsy.