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Objectives To evaluate the effect of pre-scan blood glucose levels (BGL) on standardized uptake value (SUV) in 18 F-FDG-PET scan. Methods A literature review was performed in the MEDLINE, Embase, and Cochrane library databases. Multivariate regression analysis was performed on individual datum to investigate the correlation of BGL with SUV max and SUV mean adjusting for sex, age, body mass index (BMI), diabetes mellitus diagnosis, 18 F-FDG injected dose, and time interval. The ANOVA test was done to evaluate differences in SUV max or SUV mean among five different BGL groups (< 110, 110-125, 125-150, 150-200, and > 200 mg/dl). Results Individual data for a total of 20,807 SUV max and SUV mean measurements from 29 studies with 8380 patients was included in the analysis. Increased BGL is significantly correlated with decreased SUV max and SUV mean in brain (p < 0.001, p < 0.001,) and muscle (p < 0.001, p < 0.001) and increased SUV max and SUV mean in liver (p = 0.001, p = 0004) and blood pool (p = 0.008, p < 0.001). No significant correlation was found between BGL and SUV max or SUV mean in tumors. In the ANOVA test, all hyperglycemic groups had significantly lower SUVs compared with the euglycemic group in brain and muscle, and significantly higher SUVs in liver and blood pool. However, in tumors only the hyperglycemic group with BGL of > 200 mg/dl had significantly lower SUV max. Conclusion If BGL is lower than 200 mg/dl no interventions are needed for lowering BGL, unless the liver is the organ of interest. Future studies are needed to evaluate sensitivity and specificity of FDG-PET scan in diagnosis of malignant lesions in hyperglycemia.

Measured activity ratios that fall within our normal range are likely to represent normal periprosthetic osteoblastic activity. Measured activity ratios that fall above the upper cut-offs of our normal range are likely to be abnormal. The cut-offs are robust in clinical practice and have utility in discriminating normal from abnormal stabilized arthroplasties where visual interpretation is ambiguous. Elevated AC/RA under 12 months and FC/RF under 24 months may represent normal periprosthetic activity and should be interpreted with caution.