Effective dose to patient measurements in flat-detector and multislice computed tomography: a comparison of applications in neuroradiology
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Flat-detector CT (FD-CT) is used for a variety of applications. Additionally, 3D rotational angiography (3D DSA) is used to supplement digital subtraction angiography (DSA) studies. The aim was to measure and compare the dose of (1) standard DSA and 3D DSA and (2) analogous FD-CT and multislice CT (MSCT) protocols.
Using an anthropomorphic phantom, the effective dose to patients (according to ICRP 103) was measured on an MSCT and a flat-detector angiographic system using standard protocols as recommended by the manufacturer.
(1) Evaluation of DSA and 3D DSA angiography protocols: ap.-lat. Standard/low-dose series 1/0.8 mSv, enlarged oblique projection 0.3 mSv, 3D DSA 0.9 mSv (limited coverage length 0.3 mSv). (2) Comparison of FD-CT and MSCT: brain parenchyma imaging 2.9 /1.4 mSv, perfusion imaging 2.3/4.2 mSv, temporal bone 0.2 /0.2 mSv, angiography 2.9/3.3 mSv, limited to the head using collimation 0.5/0.5 mSv.
The effective dose for an FD-CT application depends on the application used. Using collimation for FD-CT applications, the dose may be reduced considerably. Due to the low dose of 3D DSA, we recommend using this technique to reduce the number of DSA series needed to identify working projections.
• Effective dose of FD-CT in comparison to MSCT is in comparable range.
• Collimation decreases the dose of FD-CT effectively.
• Effective dose of 3-D angiography is identical to 2-D DSA.
• Different FD-CT programs have different dose.
KeywordsFlat-detector CT Multislice CT Effective dose to patient Thermoluminescent dosimetry Neuroradiology
The scientific guarantor of this publication is Prof. Arnd Doerfler. The authors of this manuscript declare relationships with the following companies: Rosemarie Banckwitz, Christoph Koehler and Kevin Royalty are full-time Siemens employees. The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article. The authors state that this work has not received any funding. No complex statistical methods were necessary for this paper. Institutional review board approval was not required because we performed a phantom study. Human subjects were not involved. Animals were not involved. No study subjects or cohorts have been previously reported. Methodology: experimental.
- 14.International Commission on Radiological Protection (2007) 2007 Recommendations of the ICRP. ICRP Publication 103. Ann. ICRP 37(2–4). Elsevier Science LtdGoogle Scholar
- 15.Exact description available via http://www.thermoscientific.com
- 16.Exact description of the ionization chamber, annealing oven and annealing procedure available via http://www.ptw.de
- 17.Information available at http://www.dkd.eu
- 19.Paul J, Banckwitz R, Krauss B, Vogl TJ, Maentele W, Bauer RW (2012) Estimation and comparison of effective dose (E) in standard chest CT by organ dose measurements and dose-length-product methods and assessment of the influence of CT tube potential (energy dependency) on effective dose in a dual-source CT. Eur J Radiol 81:e507–e512CrossRefPubMedGoogle Scholar
- 26.Struffert T, Deuerling-Zheng Y, Kloska S, Engelhorn T, Strother CM, Kalender WA et al (2010) Flat detector CT in the evaluation of brain parenchyma, intracranial vasculature, and cerebral blood volume: a pilot study in patients with acute symptoms of cerebral ischemia. AJNR Am J Neuroradiol 31:1462–1469CrossRefPubMedGoogle Scholar