A method for correcting Positron Emission Tomography (PET) data includes adjusting a tube current generated by the CT imaging system to a second tube current value that is less than a first tube current value used to generate diagnostic quality CT images, and imaging the patient with the CT imaging system set at the second tube current value. The method also includes generating a plurality of computed tomography (CT) projection data from the CT imaging system and preprocessing the CT projection data to generate preprocessed CT projection data. The method further includes filtering the preprocessed CT projection data to reduce electronic noise to generate filtered CT projection data, and performing a minus logarithmic operation on the filtered CT projection data to generate the corrected PET data.