Lower doses, faster acquisitions: Experts share how to improve PET scans for peds

Experts recently uncovered “favorable findings” associated with the image quality of FDG PET/CT and reduced acquisition times for children and young adults. 

These findings can be found this week in the American Journal of Roentgenology, where experts shared how they were able to reduce FDG PET scan acquisition times by 33%, thus reducing the amount of total radiation exposure to more vulnerable pediatric patients. 

The retrospective study included 27 children and young adults who had undergone clinically indicated whole-body FDG PET/CT examinations on a 25-cm axial FOV PET/CT system at 90 seconds per bed position. To simulate the acquisition positions, raw data were reprocessed at 60, 55, 50, 45, 40 and 30 seconds. Qualitative measures, such as SUV measurements were calculated after three radiologists analyzed the reconstructed images. 

Based on the radiologists' assigned Likert scores for lesion conspicuity, normal structure conspicuity, image quality and image noise, there were no significant qualitative differences in the images derived from the 90 and 60 second scans. When acquisition times dropped below 55 seconds, however, image quality steadily deteriorated. Starting below 55 seconds, differences in image noise were observed; at 45 seconds conspicuity of normal structures and overall image quality degraded, as did lesion conspicuity when scans times of 40 seconds or less were simulated.

Overall, SUV measures did not vary significantly throughout the series of acquisition times, except for the liver at 60 seconds/bed. 

“Favorable findings for the simulated 60 seconds/bed acquisition suggest that, in children and young adults imaged on a 25-cm FOV digital PET scanner, acquisition time or administered FDG activity may be decreased by approximately 33% from the clinical standard without significantly impacting image quality,” corresponding author Andrew T. Trout, of the Department of Radiology at Cincinnati Children's Hospital Medical Center, and co-authors shared. 

These findings, the authors concluded, suggest that faster acquisition times and reduced pediatric doses can be achieved without sacrificing image quality. 

View the study abstract here

Reference: 

Simulated Reduced-Count Whole-Body FDG PET: Evaluation in Children and Young Adults Imaged on a Digital PET Scanner. Vinicius de Padua V. Alves, Samuel Brady, Nadeen Abu Ata, Yinan Li, Joseph MacLean, Bin Zhang, Susan E. Sharp, and Andrew T. Trout. American Journal of Roentgenology. 

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In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She joined Innovate Healthcare in 2021 and has since put her unique expertise to use in her editorial role with Health Imaging.

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