The Practice of Pediatric PET/CT in North America
Objectives: To characterize the practice of PET/CT in children at North American institutions with substantial pediatric practices.
Methods: Nineteen institutions within North American that were either dedicated pediatric hospitals or academic hospitals with substantial pediatric nuclear medicine practices were invited to participate in an email survey. The survey inquired into the demographics and the model of PET/CT scanner they routinely use for imaging children. The sites were asked whether they routinely acquire a diagnostic or low-dose (for attenuation correction or anatomical correlation) CT in the context of PET/CT and how these studies are routinely acquired. For 3 hypothetical patients (weighing 20, 50 and 75 kg), the sites were asked to provide CT acquisition parameters for both diagnostic and low-dose PET/CT including: choice of kVp, whether automatic exposure control (AEC) with tube current or kV selection was used and the choice of control parameters for image quality (e.g. Quality Reference mAs and Noise Index).
Results: All 19 sites responded to the survey. The number of PET/CT scans performed in children per week varied greatly across the sites (range=1.5 to 20, mean = 6.2, median=4). By vendor, 9, 5 and 5 sites had GE, Siemens and Philips scanners, respectively. Fifteen of the 19 sites indicated that they acquired diagnostic (Dx) scans in conjunction with PET/CT and 18 performed non-Dx scans. For those that acquired Dx scans, 4 acquired the CT over the entire PET field of view, 6 to a limited region at the time of the PET/CT and 5 performed a limited CT separate for the PET/CT but on the same scanner. Only 2 of the sites acquired IV contrast at the time of the PET/CT scan. For DX studies, the vast majority of sites used AEC in the CT protocols whereas AEC was used less for non-DX scans.
Conclusion: There is a high level of variability in both the way PET/CT exams are ordered and performed, even among institutions with substantial pediatric PET imaging practices.