An applicable method for PET/CT image quality assessment and comparison among three PET/CT systems with similar physical performance in cancer patients.

This research proposes a method with specific procedure guideline for clinical PET/CT image quality assessment according to physicians' behavior of image interpretation and explore the relationship between image quality and image systems with similar physical performance. Clinical PET/CT were divided according to body location: brain, chest, abdomen and pelvic cavity. We explored the lesions and suspicious regions where radiologists concerned most through eye-tracker and behavior observation study to generate an assessment checklist. Fifty-five patients who were statistically consistent in age, weight and height were studied. Thirty-seven were scanned with an experimental scanner A and control systems B or C because their clinical pathways required PET/CT examinations at short intervals, the other 18 were scanned with scanners A and C. The grade of every system's PET, CT and PET/CT image performance on the four parts was calculated by subtraction of mean value and variance between experimental and control systems. The scoring checklist was set for PET, CT and PET/CT images in four parts respectively, and a standard procedure guideline was formulated for assessment. Using assessment criteria, the statistical results objectively reflected certain systems' superiority on certain modalities and certain parts of the body. Our criteria for clinical PET/CT image quality assessment and comparison were efficient.