We present a case of unusually intense Fluorodeoxyglucose uptake in the intercostal muscles during a Fluorodeoxyglucose positron emission tomography (FDG-PET). We hypothesized that severe left ventricular failure causing the patient to be short of breath during the study in association with insulin injection as part of study protocol led to the intense uptake of FDG in the respiratory muscles causing such an unusual appearance.