Abstract
Purpose
The aim of this study was to introduce a prototype cone-beam computed tomography system equipped with a flat panel detector (FPD-CT system) and measure its radiation dose and spatial and lowcontrast resolution.
Materials and methods
A patient was rotated in a sitting position, and cone beam data were acquired with the flat panel detector from a fixed X-ray tube. Absorbed dose, spatial and low-contrast resolution, and variation in the CT attenuation value were assessed quantitatively in the acrylic phantom. The visibility of normal blood vessels in clinical images of seven patients was analyzed qualitatively by five board-certified radiologists. These quantitative and qualitative data were compared between the FPD-CT system and multidetector row CT (MDCT).
Results
Minimal low-contrast sensitivity and a moderate spatial resolution were demonstrated in images of central lung fields acquired by FPD-CT. The absorbed dose in the FPD-CT system decreased to approximately 2.5% of the dose in the MDCT system.
Conclusion
Considering crossover structures in normal blood vessels and bronchi in the central areas of lung fields, this result implies that fairly acceptable spatial resolution can be realized with FPD-CT for detection and frequent follow-up of pulmonary abnormalities in the central lung fields.
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References
Chotas HG, Dobbins JT, Ravin CE. Principles of digital radiography with large-area, electronically readable detectors: a review of the basics. Radiology 1999;210:595–599.
Swensen SJ, Jett JR, Sloan JA, Midthun DE, Hartman TE, Sykes AM, et al. Screening for lung cancer with low-dose spiral computed tomography. Am J Respir Crit Care Med 2002;165:508–513.
Strotzer M, Gmeinweiser JK, Völk M, Fründ R, Seitz J, Feuerbach S. Detection of simulated chest lesions with normal and reduced radiation dose: comparison of conventional screen-film radiography and a flat-panel X-ray detector based on amorphous silicon. Invest Radiol 1998;33:98–103.
Kakeda S, Korogi Y, Ohnari N, Hatakeyama Y, Moriya J, Oda N, et al. 3D digital subtraction angiography of intracranial aneurysms: comparison of flat panel detector with conventional image intensifier TV system using a vascular phantom. AJNR Am J Neuroradiol 2007;28:839–843.
Closmann JJ, Schmidt BL. The use of cone beam computed tomography as an aid in evaluating and treatment planning for mandibular cancer. J Oral Maxillofac Surg 2007;65:766–771.
Honda K, Larheim TA, Maruhashi K, Matsumoto K, Iwai K. Osseous abnormalities of the mandibular condyle: diagnostic reliability of cone beam computed tomography compared with helical computed tomography based on an autopsy material. Dentomaxillofac Radiol 2006;35:152–157.
Orlov IM, Morgan DG, Cheng RH. Efficient implementation of a filtered back-projection algorithm using a voxel-by-voxel approach. J Struct Biol 2006;154:287–296.
Eder V, Bernis F, Drummn M, Diarra MI, Baulieu F, Léger C, et al. Three-dimensional analysis of left ventricle regional wall motion by using gated blood pool tomography. Nucl Med Commun 2004;25:971–978.
Hubell JH. Photon mass attenuation and mass energyabsorption coefficients for H, C, N, O, Ar and seven mixtures from 0.1 Kev and 20 MeV. Radiat Res 1977;70:58–81.
Gupta R, Grasruck M, Suess C, Bartling SH, Schmidt B, Stierstorfer K, et al. Ultra-high resolution flat-panel volume CT: fundamental principles, design architecture, and system characterization. Eur Radiol 2006;16:1191–1205.
Strotzer M, Völk M, Fründ R, Hamer O, Zorger N, Feuerbach S. Routine chest radiography using a flatpanel detector; image qualtiy at standard detector dose and 33% dose reduction. AJR Am J Roentgenol 2002;178:169–171.
Markowitz SB, Miller A, Miller J, Manowitz A, Kieding S, Sider L, et al. Ability of low-dose helical CT to distinguish between benign and malignant noncalcified lung nodules. Chest 2007;131:1028–1034.
Swensen SJ, Jett JR, Hartman TE, Midthun DE, Sloan JA, Sykes AM, et al. Lung cancer screening with CT: Mayo Clinic experience. Radiology 2003;226:756–761.
Sone S, Takashima S, Li F, Yang Z, Honda T, Murayama Y, et al. Mass screening for lung cancer with mobile spiral computed tomography scanner. Lancet 1998;351:1242–1245.
Nishizawa K, Mori S, Ohno M, Yanagawa N, Yoshida T, Akahane K, et al. Patient dose estimation for multi-detector row CT examinations. Radiat Prot Dosimetry 2008;128:98–105.
Henschke CI, Yankelevitz DF, Naidich DP, McCaulev DI, McGuinness G, Libby DM, et al. CT screening for lung cancer: suspiciousness of nodules according to size on baseline scans. Radiology 2004;231:164–168.
Gerber TC, Kuro RS, Morin RL. Techniques and parameters for estimating radiation exposure and dose in cardiac computed tomography. Int J Cardiovasc Imaging 2005;21;165–76.
Stolzmann P, Scheffel H, Schertler T, Frauenfelder T, Leschka S, Husmann L, et al. Radiation dose estimates in dual-source computed tomography coronary angiography. Eur Radiol 2008;18:592–599.
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Nagatani, Y., Nitta, N., Takahashi, M. et al. Ultra-low-dose computed tomography system with a flat panel detector: assessment of radiation dose reduction and spatial and low contrast resolution. Radiat Med 26, 627–635 (2008). https://doi.org/10.1007/s11604-008-0285-0
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DOI: https://doi.org/10.1007/s11604-008-0285-0