A computer algorithm to standardize medical images acquired using positron emission tomography.

Positron emission tomography (PET) is a commonly utilized imaging modality used for body-wide assessments of a variety of diseases, including cancer.  Measurements derived from PET images are used to make diagnostic, staging, and treatment decisions for improved patient care. The standardized uptake value (SUV) is a quantitative measurement widely utilized for a semi-quantitative PET assessment in clinical practice. Patient-related factors including body weight and habitus, and technical factors including image acquisition methods and image reconstruction methods may adversely affect the accuracy of PET-derived measurements. Attempting to account for all adverse factors remains a challenge to the goal of accurate and reproducible measurements from PET images.

A computer algorithm to standardize PET images and reduce errors in PET quantification. This algorithm does not use patient-related or scanner-related factors which allows it to be applied across scanners and image acquisition protocols and even for already existing data sets.

The standardization operation is applicable to both PET and SUV images. A calibration step is first applied to a series of training images from which key parameters characterizing a standardization mapping are determined. This operation is performed only once. Subsequently, for any given image to be standardized, a standardization transformation is applied by estimating the corresponding parametric values for the given image and utilizing the learned parametric values. PET and SUV images are standardized separately. 

• Post-acquisition application
• Applicable to whole-body PET images
• Decrease in variability of measurements of radiotracer uptake within and between patient scans within tissues or lesions of interest
• Can be incorporated into existing PET image analysis software packages
• Fully automated