Eray Atli MD, Presenter: Nothing to Disclose

Erhan Akpinar MD, Abstract Co-Author: Nothing to Disclose

Berna Sayan Oguz MD, Abstract Co-Author: Nothing to Disclose

Mithat Haliloglu MD, Abstract Co-Author: Nothing to Disclose

To assess radiation dose reduction and image quality with high-pitch dual-source CT (DSCT) in comparison with standard pitch with conventional pediatric abdominal CT.

A total of 48 patients (median age, 51,8 months) underwent high-pitch abdominal CT in this institutional review board–approved HIPAA-compliant prospective study. High-pitch (value:3) mode CT was performed with 64-slice DSCT. This was compared to a group of 37 patients (median age, 60.7months) who underwent conventional pediatric abdominal CT (pitch: <1.5). Scanning protocols were adjusted for clinical indication and patient weight in both groups. Anteroposterior (APD) and lateral (LD) abdominal diameters at the umbilical level were measured in all patients and effective diameter (ED) was calculated. Scan time (ST) and length (SL), qualitative (artifacts related to patient or bowel movement, diagnostic confidence, subjective noise) and quantitative (density measurements from liver, abdominal aorta, psoas muscle and outside of abdominal wall) measures of noise, CTDIvolume, dose length products (DLP), size specific dose estimate (SSDE; calculated by using conversion factors given by AAPM at report no: 204) were assessed in both groups. Comparisons were made by using chi-square test, independent sample t test and Mann-Whitney U test. 

Both patient groups were similar with respect to age, APD, LD, ED and SL. Mean ST of high-pitch abdomen CT was 1.57 secs, while it was 9.94 secs in standard pitch mode CT. In comparison with conventional pitch mode, high pitch mode of DSCT reduced radiation exposure by 67% (5.18 vs. 1.7 mGy, SSDE according to ED); CTDlvolume, DLE and SSDE parameters were significantly lower in high pitch mode (p<0.001). Subjective noise on high pitch imaging did not have any effect on diagnostic confidence and quantitative measures of noise were similar among both types of imaging. Less artifacts, either related to patient or bowel movement, were observed with high pitch imaging (p<0.001).  

The use of high pitch DSCT significantly decreases scan times and radiation exposure when compared to conventional CT. Image quality and diagnostic confidence, however, is still similar in both imaging techniques.

In pediatric abdominal imaging, high pitch DSCT provides fast scanning, less motion artifacts and significant reductions in radiation exposure without adversely affecting image quality.

Atli, E, Akpinar, E, Sayan Oguz, B, Haliloglu, M, High-pitch Dual Source Computed Tomography of Pediatric Abdomen.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13026471.html