What happens to glucose levels during monitoring after glucose loading?

After glucose loading, monitoring glucose levels is crucial, particularly in the context of Positron Emission Tomography (PET) using fluorodeoxyglucose (FDG). Glucose acts as a radiotracer and is taken up by metabolically active tissues, which is the principle behind PET imaging.

The correct answer states that glucose levels should be under 150 mg/dL for FDG injection. This is particularly important because elevated blood glucose levels can affect the accuracy and efficacy of the FDG-PET scan. When glucose levels are too high, it can lead to increased competition for the uptake of FDG by the tissues, thereby potentially masking or altering the images produced during the scan.

During a PET scan, the goal is to have the glucose levels primarily in a range that ensures optimal FDG uptake by the target tissues while minimizing background interference from elevated blood sugar levels. Keeping the glucose levels under 150 mg/dL generally indicates that there is an appropriate environment for FDG to show the metabolic activity needed for accurate imaging.

In contrast, having glucose levels that remain constant or fall rapidly would not be indicative of the ideal conditions for a PET scan with FDG. Consistently high levels beyond the accepted threshold could lead to misleading results in