Purpose or Case Report: Recently JACHO proposed to address double scanning in pediatric chest CT, yet there are no data to determine whether this takes place; similarly, there is discussion regarding validity of sending pediatric patients to adult-focused practices for routine imaging by third party payors. Our purpose is to review the technical factors that impact upon radiation dose and image quality in CT scans of children referred from adult-focused practices to a children’s hospital, referenced to pre-Image Gently values. To our knowledge this is the first such review that includes body and neuro scans and extensive technique and exposure data
Methods & Materials: This IRB-approved study assessed 100 randomly selected external CT scans. The study CDs were uploaded into Sante DICOM software for viewing and analysis. Study type, indication, gender, age, use of oral or IV contrast, number of phases, reformats, slice thickness (ST) DLP, CTDIvol, kV, mA, mAs, phantom size, iterative reconstruction (IR) vs filtered back projection (FBP)
Results: Of the 100 scans, 56% were body; 44% were neuro. Mean patient age was 9.4 years [0-24]. 38/51 (75%) A/P scans were done for pain, and of these 6 (16%) were done without IV contrast. Head CT was done for trauma in 15 (48%) and for seizure, H/A, N/V in 15 (48%). Of 51 A/P studies, 10 (20%) were multiphase, 3 were triple phase; of the 44 neuro studies, 3 (7%) were multiphase. Biplane reformats were available in less than half (43%) of body scans. The mean DLP for body scans was 496mGy*cm [32-2583], and for neuro 662 [102-2355]. Phantom size was available in 47/56 body scans, and a 16 inch phantom was used in only 1; phantom size was available in 39/44 neuro studies, and the 32 inch phantom was used in 6. Mean mA, mAs, kV, ST and DLP for neuro and body scans in 3 age groups: 0-6; 7-10 and >10 years are outlined in Table
Conclusions: Since 2001 (Paterson AJR 2001;176:297) our data indicate that adjustment for size is not universally applied in scan settings, or choice of ST; phantom size used in estimation of DLP is chosen more based on the body part scanned than on the patient size; the variation in dose is extremely high, with DLP’s in the greater than 2000 range in some children; despite the multiphase examinations, triplane reformats are not universally provided