Normal organ standard uptake values in carbon-11 acetate PET imaging

The goal of this study was to determine normal standard uptake values of carbon-11 (11C) acetate in healthy organs. By accurately determining the range of physiologic activity, abnormal focal or diffuse 11C-acetate activity can be more accurately assessed and thus improve the sensitivity and specificity of this emerging diagnostic PET agent.

We reviewed all 55 patients (mean age+/-SD 64.8+/-10.8, age range 35-88 years) who underwent 11C-acetate PET/computed tomography at our institution from 2005 to 2007. Regions of interest were drawn in organs that were devoid of clinical or imaging evidence of disease. The maximum standard uptake value for each region was calculated and analyzed for mean, standard deviation, and 95% confidence intervals.

The results are presented as average maximum standard uptake value+/-1 SD with the pancreas, liver, spleen and salivary glands showing the greatest 11C-acetate avidity. A review of the literature shows our results to be similar to those published earlier.

Accurate knowledge of normal biodistribution and standardized uptake values will provide the foundation for assessing focal or diffuse organ disease while using this PET agent.