Abstract
Scattered radiation is a major concern impacting X-ray image-guided procedures in two ways. First, back-scatter significantly contributes to patient (skin) dose during complicated interventions. Second, forward-scattered radiation reduces contrast in projection images and introduces artifacts in 3-D reconstructions. While conventionally employed anti-scatter grids improve image quality by blocking X-rays, the additional attenuation due to the anti-scatter grid at the detector needs to be compensated for by a higher patient entrance dose. This also increases the room dose affecting the staff caring for the patient. For skin dose quantification, back-scatter is usually accounted for by applying pre-determined scalar back-scatter factors or linear point spread functions to a primary kerma forward projection onto a patient surface point. However, as patients come in different shapes, the generalization of conventional methods is limited. Here, we propose a novel approach combining conventional techniques with learning-based methods to simultaneously estimate the forward-scatter reaching the detector as well as the back-scatter affecting the patient skin dose. Knowing the forward-scatter, we can correct X-ray projections, while a good estimate of the back-scatter component facilitates an improved skin dose assessment. To simultaneously estimate forward-scatter as well as back-scatter, we propose a multi-task approach for joint back- and forward-scatter estimation by combining X-ray physics with neural networks. We show that, in theory, highly accurate scatter estimation in both cases is possible. In addition, we identify research directions for our multi-task framework and learning-based scatter estimation in general.
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References
Amanatides, J., Woo, A.: A fast voxel traversal algorithm for ray tracing. In: Proceedings of the Eurographics (1987)
Badal, A., Badano, A.: Accelerating Monte Carlo simulations of photon transport in a voxelized geometry using a massively parallel graphics processing unit. Med. Phys. 36(11), 4878–4880 (2009)
Baer, M., Kachelrieß, M.: Hybrid scatter correction for CT imaging. Phys. Med. Biol. 57(21), 6849–6867 (2012)
Balter, S.: Methods for measuring fluoroscopic skin dose. Pediatr. Radiol. 36(2), 136–140 (2006). https://doi.org/10.1007/s00247-006-0193-3
Bejarano, T., De Ornelas Couto, M., Mihaylov, I.: Head-and-neck squamous cell carcinoma patients with CT taken during pre-treatment, mid-treatment, and post-treatment dataset. The Cancer Imaging Archive (2018)
Chan, H.P., Doi, K.: Investigation of the performance of antiscatter grids: Monte Carlo simulation studies. Phys. Med. Biol. 27(6), 785–803 (1982)
Clark, K., et al.: The cancer imaging archive (TCIA): maintaining and operating a public information repository. J. Digit. Imaging 26(6), 1045–1057 (2013). https://doi.org/10.1007/s10278-013-9622-7
Freud, N., Duvauchelle, P., Pistrui-Maximean, S., Létang, J.M., Babot, D.: Deterministic simulation of first-order scattering in virtual x-ray imaging. Nucl. Instrum. Methods Phys. Res. B 222(1), 285–300 (2004)
Fritz, S., Jones, A.K.: Guidelines for anti-scatter grid use in pediatric digital radiography. Pediatr. Radiol. 44(3), 313–321 (2013). https://doi.org/10.1007/s00247-013-2824-9
Glorot, X., Bordes, A., Bengio, Y.: Deep sparse rectifier neural networks. In: Proceedings of the Fourteenth International Conference on Artificial Intelligence and Statistics, pp. 315–323 (2011)
Ingleby, H.R., Lippuner, J., Rickey, D.W., Li, Y.L., Elbakri, I.A.: Fast analytical scatter estimation using graphics processing units. J. X-Ray Sci. Technol. 23(2), 119–133 (2015)
Johnson, P.B., Borrego, D., Balter, S., Johnson, K., Siragusa, D., Bolch, W.E.: Skin dose mapping for fluoroscopically guided interventions. Med. Phys. 38(10), 5490–5499 (2011)
Kingma, D., Ba, J.: Adam: a method for stochastic optimization. In: Proceedings of the International Conference on Learning Representations (ICLR), December 2014
Li, H., Mohan, R., Zhu, X.R.: Scatter kernel estimation with an edge-spread function method for cone-beam computed tomography imaging. Phys. Med. Biol. 53(23), 6729–6748 (2008)
Loy Rodas, N., Padoy, N.: Seeing is believing: increasing intraoperative awareness to scattered radiation in interventional procedures by combining augmented reality, Monte Carlo simulations and wireless dosimeters. Int. J. Comput. Assist. Radiol. Surg. 10(8), 1181–1191 (2015). https://doi.org/10.1007/s11548-015-1161-x
Maier, J., et al.: Real-time scatter estimation for medical CT using the deep scatter estimation: Method and robustness analysis with respect to different anatomies, dose levels, tube voltages, and data truncation. Med. Phys. 46(1), 238–249 (2019)
Ohnesorge, B., Flohr, T., Klingenbeck-Regn, K.: Efficient object scatter correction algorithm for third and fourth generation CT scanners. Eur. Radiol. 9(3), 563–569 (1999). https://doi.org/10.1007/s003300050710
Petoussi-Henss, N., Zankl, M., Drexler, G., Panzer, W., Regulla, D.: Calculation of backscatter factors for diagnostic radiology using Monte Carlo methods. Phys. Med. Biol. 43(8), 2237–2250 (1998)
Poludniowski, G., Evans, P.M., Hansen, V.N., Webb, S.: An efficient Monte Carlo-based algorithm for scatter correction in keV cone-beam CT. Phys. Med. Biol. 54(12), 3847–3864 (2009)
Rana, V.K., Rudin, S., Bednarek, D.R.: A tracking system to calculate patient skin dose in real-time during neurointerventional procedures using a biplane x-ray imaging system. Med. Phys. 43(9), 5131–5144 (2016)
Ronneberger, O., Fischer, P., Brox, T.: U-Net: convolutional networks for biomedical image segmentation. In: Navab, N., Hornegger, J., Wells, W.M., Frangi, A.F. (eds.) MICCAI 2015. LNCS, vol. 9351, pp. 234–241. Springer, Cham (2015). https://doi.org/10.1007/978-3-319-24574-4_28
Roser, P., et al.: Physics-driven learning of x-ray skin dose distribution in interventional procedures. Med. Phys. 46(10), 4654–4665 (2019)
Roser, P., et al.: Fully-automatic CT data preparation for interventional x-ray skin dose simulation. In: Bildverarbeitung für die Medizin 2020. I, pp. 125–130. Springer, Wiesbaden (2020). https://doi.org/10.1007/978-3-658-29267-6_26
Roth, H., et al.: A new 2.5 d representation for lymph node detection in CT. The Cancer Imaging Archive (2018)
Rührnschopf, E.P., Klingenbeck, K.: A general framework and review of scatter correction methods in cone-beam CT. Part 2: scatter estimation approaches. Med. Phys. 38(9), 5186–5199 (2011)
Rührnschopf, E.P., Klingenbeck, K.: A general framework and review of scatter correction methods in x-ray cone-beam computerized tomography. Part 1: scatter compensation approaches. Med. Phys. 38(7), 4296–4311 (2011)
Sun, M., Star-Lack, J.M.: Improved scatter correction using adaptive scatter kernel superposition. Phys. Med. Biol. 55(22), 6695–6720 (2010)
Ubeda, C., Vano, E., Gonzalez, L., Miranda, P.: Influence of the antiscatter grid on dose and image quality in pediatric interventional cardiology x-ray systems. Catheter. Cardio. Inte. 82(1), 51–57 (2013)
Wang, A., et al.: Acuros CTS: a fast, linear Boltzmann transport equation solver for computed tomography scatter - Part II: system modeling, scatter correction, and optimization. Med. Phys. 45(5), 1914–1925 (2018)
Yao, W., Leszczynski, K.W.: An analytical approach to estimating the first order scatter in heterogeneous medium. II. A practical application. Med. Phys. 36(7), 3157–3167 (2009)
Zhong, X., Strobel, N., Kowarschik, M., Fahrig, R., Maier, A.: Comparison of default patient surface model estimation methods. In: Bildverarbeitung für die Medizin 2017. I, pp. 281–286. Springer, Heidelberg (2017). https://doi.org/10.1007/978-3-662-54345-0_64
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Roser, P. et al. (2020). Simultaneous Estimation of X-Ray Back-Scatter and Forward-Scatter Using Multi-task Learning. In: Martel, A.L., et al. Medical Image Computing and Computer Assisted Intervention – MICCAI 2020. MICCAI 2020. Lecture Notes in Computer Science(), vol 12262. Springer, Cham. https://doi.org/10.1007/978-3-030-59713-9_20
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