2026-05-05T19:20:38Zhttps://uvadoc.uva.es/oai/request

oai:uvadoc.uva.es:10324/151672021-06-23T13:27:22Zcom_10324_1191com_10324_931com_10324_894col_10324_1379

Ramos Llordén, Gabriel Vegas Sánchez-Ferrero, Gonzalo Martín Fernández, Marcos Antonio Alberola López, Carlos Aja Fernández, Santiago Ultrasound Imaging Speckle Filter Anisotropic Diffusion Memory Equations Volterra Equations Ultrasound imaging exhibits considerable difficulties for medical visual inspection and for the development of automatic analysis methods due to speckle, which negatively affects the perception of tissue boundaries and the performance of automatic segmentation methods. With the aim of alleviating the effect of speckle, many filtering techniques are usually considered as a preprocessing step prior to automatic analysis methods or visual inspection. Most of the state-of-the-art filters try to reduce the speckle effect without considering its relevance for the characterization of tissue nature. However, the speckle phenomenon is the inherent response of echo signals in tissues and can provide important features for clinical purposes. This loss of information is even magnified due to the iterative process of some speckle filters, e.g., diffusion filters, which tend to produce over-filtering because of the progressive loss of relevant information for diagnostic purposes during the diffusion process. In this work, we propose an anisotropic diffusion filter with a probabilistic-driven memory mechanism to overcome the over-filtering problem by following a tissue selective philosophy. Specifically, we formulate the memory mechanism as a delay differential equation for the diffusion tensor whose behavior depends on the statistics of the tissues, by accelerating the diffusion process in meaningless regions and including the memory effect in regions where relevant details should be preserved. Results both in synthetic and real US images support the inclusion of the probabilistic memory mechanism for maintaining clinical relevant structures, which are removed by the state-of-the-art filters. 2015-12-21 2015-12-21 2015 info:eu-repo/semantics/article IEEE Trans. on Image Processing, Vol. 24, No. 1, Enero 2015 http://uvadoc.uva.es/handle/10324/15167 10.1109/TIP.2014.2371244 spa info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-nd/4.0/ Attribution-NonCommercial-NoDerivatives 4.0 International