Pediatric PET studies of constant image quality can be performed with time or dose savings of as much as 50 percent for the lightest patients (10–20 kg), according to a study published in the February issue of the Journal of Nuclear Medicine.
“Minimizing exposure to radiation is important to all patients, but especially for young children. The results of this study show that, due to children's relatively small size and light weight, it is possible to reduce radiological dose (or scan time) while preserving image quality as compared to PET imaging in adults," said lead author Roberto Accorsi, PhD, former research assistant professor of radiology in the department of radiology at Children’s Hospital of Philadelphia in Pennsylvania.
The researchers acquired and analyzed data from 73 patients (mean weight, 45.4 kg) and patient-specific noise-equivalent count rate density curves (NECD) were derived as a function of injected dose.
“When following an injection protocol proportional to weight, the NECD of PET images were found to improve for decreasing weight from the reference case of an adult-sized (70-kg) patient. As compared with height, girth and body mass index, weight was found to be the patient statistic correlating best with the dose necessary for imaging at constant NECD and time,” wrote Accorsi and colleagues.
“Results suggest that pediatric PET of constant image quality can be performed with time or dose savings, up to 50 percent for the lightest patients (10–20 kg),” concluded the authors.
"These findings mean that PET can be used in children with methods that are even more patient-specific than those currently employed," said Accorsi.