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. 2015 Jul-Sep;40(3):170-5.
doi: 10.4103/0971-6203.165073.

Cost-effective pediatric head and body phantoms for computed tomography dosimetry and its evaluation using pencil ion chamber and CT dose profiler

A Saravanakumar  1 , K Vaideki  1 , K N Govindarajan  2 , S Jayakumar  3 , B Devanand  4
Affiliations

Cost-effective pediatric head and body phantoms for computed tomography dosimetry and its evaluation using pencil ion chamber and CT dose profiler

A Saravanakumar et al. J Med Phys. 2015 Jul-Sep.

Abstract

In the present work, a pediatric head and body phantom was fabricated using polymethyl methacrylate (PMMA) at a low cost when compared to commercially available phantoms for the purpose of computed tomography (CT) dosimetry. The dimensions of head and body phantoms were 10 cm diameter, 15 cm length and 16 cm diameter, 15 cm length, respectively. The dose from a 128-slice CT machine received by the head and body phantom at the center and periphery were measured using a 100 mm pencil ion chamber and 150 mm CT dose profiler (CTDP). Using these values, the weighted computed tomography dose index (CTDIw) and in turn the volumetric CTDI (CTDIv) were calculated for various combinations of tube voltage and current-time product. A similar study was carried out using standard calibrated phantom and the results have been compared with the fabricated ones to ascertain that the performance of the latter is equivalent to that of the former. Finally, CTDIv measured using fabricated and standard phantoms were compared with respective values displayed on the console. The difference between the values was well within the limits specified by Atomic Energy Regulatory Board (AERB), India. These results indicate that the cost-effective pediatric phantom can be employed for CT dosimetry.

Keywords: CT dose profiler; CTDI phantom; Pediatric CT; pediatric radiation dose; pencil ion chamber.

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Figures

Figure 1
Figure 1
CT dose profiler. CT = Computed tomography
Figure 2
Figure 2
Piranha 557 reader
Figure 3
Figure 3
Pediatric CTDI: (a) Head phantom and (b) body phantom. CTDI = Computed tomography dose index
Figure 4
Figure 4
Dose profiles in the standard phantom: (a) Centre (b) periphery
Figure 5
Figure 5
Dose profiles in the fabricated phantom: (a) Centre (b) periphery
Figure 6
Figure 6
Variations in CTDIv with tube potential (a) head (b) body. CTDIv = Volumetric computed tomography dose index, CTDP = CT dose profiler
See this image and copyright information in PMC

References

    1. Zacharias C, Alessio AM, Otto RK, Iyer RS, Philips GS, Swanson JO, et al. Pediatric CT: Strategies to lower radiation dose. AJR Am J Roentgenol. 2013;200:950–6. - PMC - PubMed
    1. Strauss KJ, Goske MJ, Kaste SC, Bulas D, Frush DP, Butler P, et al. Image gently: Ten steps you can take to optimize image quality and lower CT dose for pediatric patients. AJR Am J Roentgenol. 2010;194:868–73. - PubMed
    1. Mettler FA, Jr, Wiest PW, Locken JA, Kelsey CA. CT scanning: Patterns of use and dose. J Radiol Prot. 2000;20:353–9. - PubMed
    1. Wiklund LM, Brolin I, Sjoholm K. Nonionic contrast media in pediatric CT: A comparative study of intravenous use of iopentol and iohexol. Acta Radiol. 1994;35:186–90. - PubMed
    1. Thomas KE, Owens CM, Britto J, Nadel S, Habibi P, Nicholson R. Efficacy of chest CT in a pediatric ICU: A prospective study. Chest. 2000;117:1697–705. - PubMed