?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Regularization+of+image+reconstruction+in+ultrasound+computed+tomography&rft.creator=Perez-Liva%2C+M&rft.creator=Herraiz%2C+JL&rft.creator=Medina-Valdes%2C+L&rft.creator=Camacho%2C+J&rft.creator=Fritsch%2C+C&rft.creator=Treeby%2C+BE&rft.creator=Udias%2C+JM&rft.description=We+propose+two+regularizations+techniques+for+a+bent-ray+(BR)+tracing+algorithm+to+reconstruct+the+speed+of+sound+maps+of+breast+tissues+in+an+Ultrasound+Computed+Tomography+(USCT)+system.+When+high+frequencies+are+employed%2C+the+use+of+BR+is+a+good+approximation+to+describe+the+propagation+of+the+front+of+the+pressure+wave.+The+quantitative+accuracy+of+the+images+reconstructed+with+the+BR+algorithm+was+evaluated+without+any+kind+of+regularization%2C+and+with+two+regularization+methods.+The+regularizations+were+based+on+some+available+a+priori+information%2C+namely+the+known+higher+and+lower+values+of+the+speed+of+sound+expected+in+the+breast+tissues%2C+and+the+maps+of+the+internal+structures+obtained+from+the+standard+reflection+ultrasound+(US)+imaging.+The+use+of+the+proposed+regularizations+in+the+implemented+algorithm+improves+the+convergence+and+quality+of+the+resulting+images%2C+although+further+improvements+are+still+possible.+These+methods+will+help+obtaining+quantitative+US+images+in+a+reasonable+amount+of+time%2C+expanding+the+possibilities+and+applications+of+this+technique.&rft.subject=Tumours%2C%0D%0Abiomedical+ultrasonics%2C%0D%0Acancer%2C%0D%0Acomputerised+tomography%2C%0D%0Aimage+reconstruction%2C%0D%0Amedical+image+processing%2C+pressure+wave%2C%0D%0Aregularization%2C%0D%0Aimage+reconstruction%2C%0D%0Aultrasound+computed+tomography%2C%0D%0Abent-ray+tracing+algorithm%2C%0D%0Asound+maps%2C%0D%0Abreast+tissues%2C%0D%0AUSCT+system&rft.publisher=IEEE&rft.date=2016-10-03&rft.type=Proceedings+paper&rft.language=eng&rft.source=+++++In%3A++2015+IEEE+Nuclear+Science+Symposium+and+Medical+Imaging+Conference+(NSS%2FMIC).++(pp.+pp.+1-3).++IEEE+(2016)+++++&rft.format=text&rft.identifier=https%3A%2F%2Fdiscovery.ucl.ac.uk%2Fid%2Feprint%2F1529179%2F1%2Ftreeby_PID4009547.pdf&rft.identifier=https%3A%2F%2Fdiscovery.ucl.ac.uk%2Fid%2Feprint%2F1529179%2F&rft.rights=open