Article

Point/Counterpoint. Cone beam x-ray CT will be superior to digital x-ray tomosynthesis in imaging the breast and delineating cancer.

Radiology Department, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
Medical Physics (Impact Factor: 2.64). 03/2008; 35(2):409-11. DOI: 10.1118/1.2825612
Source: PubMed

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    • "In the case when such changes may be clinically significant, original radiotherapy plan should be adapted or modified to conform to the current (e.g. CBCT) images prior to further treatment to ensure that the intended dose delivery is achieved (Karellas et al 2008). Several studies on dose calculations based on CBCT images have been conducted investigating the feasibility of cone-beam-based plans for dosimetry calculations (Lee et al 2007, 2008, Ding et al 2007b, Nijkamp et al 2008, Yang et al 2007, Yoo and Yin 2006, Richter et al 2008). "
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    ABSTRACT: The purpose of this study was to investigate the effect of different acquisition parameters and to determine the optimal set of acquisition parameters of projection views (PVs) for the new developed digital breast tomosynthesis (DBT) system. The DBT imaging parameters were optimized using 32 different acquisition sets with six angular ranges (±5°, ±10°, ±13°, ±17°, ±21°, and ±25°) and eight projection views (5, 11, 15, 21, 25, 31, 41, and 51 prjections). In addition to the contrastto-noise ratio (CNR), the artifact spread function (ASF) was used to quantify the in-focus plane artifacts along the z-direction in order to explore the relationship between the acquisition parameters and the image quality. A commercially, available breast-mimicking phantom was imaged to qualitatively verify our results. Our results show that a wide angular range improved the reconstructed image quality in the z-direction. If a large number of projections are acquired, then the electronic noise may dominate the CNR due to reduce the radiation dose per projection. Although increasing angular range was found to improve the vertical resolution, due to greater effective breast thickness, the image quality of microcalcifications in the in-focus plane was also found not to be improved by increasing the noise. Therefore, potential trade-offs of these physical imaging properties must be considered to optimize the acquisition configuration of a DBT system. Our results suggest possible directions for further improvements in DBT systems for high quality imaging.
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