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Author Soriano, A.; Gonzalez, A.; Orero, A.; Moliner, L.; Carles, M.; Sanchez, F.; Benlloch, J.M.; Correcher, C.; Carrilero, V.; Seimetz, M.
Title Attenuation correction without transmission scan for the MAMMI breast PET Type Journal Article
Year 2011 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 648 Issue Pages S75-S78
Keywords Breast PET; Attenuation correction
Abstract (down) Whole-body Positron Emission Tomography (PET) scanners are required in order to span large Fields of View (FOV). Therefore, reaching the sensitivity and spatial resolution required for early stage breast tumor detection is not straightforward. MAMMI is a dedicated breast PET scanner with a ring geometry designed to provide PET images with a spatial resolution as high as 1.5 mm, being able to detect small breast tumors ( < 1 cm). The patient lays down in prone position during the scan, thus making possible to image the whole breast, up to regions close to the base of the pectoral without the requirement of breast compression. Attenuation correction (AC) for PET data improves the image quality and the quantitative accuracy of radioactivity distribution determination. In dedicated, high resolution breast cancer scanners, this correction would enhance the proper diagnosis in early disease stages. In whole-body PET scanners, AC is usually taken into account with the use of transmission scans, either by external radioactive rod sources or by Computed Tomography (CT). This considerably increases the radiation dose administered to the patient and time needed for the exploration. In this work we propose a method for breast shape identification by means of PET image segmentation. The breast shape identification will be used for the determination of the AC. For the case of a specific breast PET scanner the procedure we propose should provide AC similar to that obtained by transmission scans as we take advantage of the breast anatomical simplicity. Experimental validation of the proposed approach with a dedicated breast PET prototype is also presented. The main advantage of this method is an important dose reduction since the transmission scan is not required.
Address [Soriano, A.; Orero, A.; Moliner, L.; Carles, M.; Sanchez, F.; Benlloch, J. M.] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46980 Paterna, Spain, Email: soriano@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000305376900021 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1069
Permanent link to this record
 
 
Author Blume, M.; Martinez-Moller, A.; Keil, A.; Navab, N.; Rafecas, M.
Title Joint Reconstruction of Image and Motion in Gated Positron Emission Tomography Type Journal Article
Year 2010 Publication IEEE Transactions on Medical Imaging Abbreviated Journal IEEE Trans. Med. Imaging
Volume 29 Issue 11 Pages 1892-1906
Keywords Gating; motion compensation; positron emission tomography (PET); reconstruction
Abstract (down) We present a novel intrinsic method for joint reconstruction of both image and motion in positron emission tomography (PET). Intrinsic motion compensation methods exclusively work on the measured data, without any external motion measurements. Most of these methods separate image from motion estimation: They use deformable image registration/optical flow techniques in order to estimate the motion from individually reconstructed gates. Then, the image is estimated based on this motion information. With these methods, a main problem lies in the motion estimation step, which is based on the noisy gated frames. The more noise is present, the more inaccurate the image registration becomes. As we show both visually and quantitatively, joint reconstruction using a simple deformation field motion model can compete with state-of-the-art image registration methods which use robust multilevel B-spline motion models.
Address [Blume, Moritz; Rafecas, Magdalena] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: moritz.blume@cs.tum.edu
Corporate Author Thesis
Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0278-0062 ISBN Medium
Area Expedition Conference
Notes ISI:000283941800007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 340
Permanent link to this record
 
 
Author Gomez-Cadenas, J.J.; Benlloch-Rodriguez, J.M.; Ferrario, P.
Title Application of scintillating properties of liquid xenon and silicon photomultiplier technology to medical imaging Type Journal Article
Year 2016 Publication Spectrochimica Acta Part B Abbreviated Journal Spectroc. Acta Pt. B
Volume 118 Issue Pages 6-13
Keywords PET; TOF; Liquid xenon; Energy resolution; High sensitivity; Coincidence resolution time (CRT); SiPMs
Abstract (down) We describe a new positron emission time-of-flight apparatus using liquid xenon. The detector is based in a liquid xenon scintillating cell. The cell shape and dimensions can be optimized depending on the intended application. In its simplest form, the liquid xenon scintillating cell is a box in which two faces are covered by silicon photomultipliers and the others by a reflecting material such as Teflon. It is a compact, homogenous and highly efficient detector which shares many of the desirable properties of monolithic crystals, with the added advantage of high yield and fast scintillation offered by liquid xenon. Our initial studies suggest that good energy and spatial resolution comparable with that achieved by lutetium oxyorthosilicate crystals can be obtained with a detector based in liquid xenon scintillating cells. In addition, the system can potentially achieve an excellent coincidence resolving time of better than 100 ps.
Address [Gomez-Cadenas, J. J.; Benlloch-Rodriguez, J. M.; Ferrario, Paola] Univ Valencia, CSIC, IFIC, E-46003 Valencia, Spain, Email: gomez@mail.cern.ch
Corporate Author Thesis
Publisher Pergamon-Elsevier Science Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0584-8547 ISBN Medium
Area Expedition Conference
Notes WOS:000374073300002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2631
Permanent link to this record
 
 
Author Tarifeño-Saldivia, A.; Soto, L.
Title Effects of gas chamber geometry and gas flow on the neutron production in a fast plasma focus neutron source Type Journal Article
Year 2014 Publication Plasma Physics and Controlled Fusion Abbreviated Journal Plasma Phys. Control. Fusion
Volume 56 Issue 12 Pages 125013 - 5pp
Keywords pulsed neutron source; repetitive plasma focus; neutron yield measurement; fast plasma focus
Abstract (down) This work reports that gas chamber geometry and gas flow management substantially affect the neutron production of a repetitive fast plasma focus. The gas flow rate is the most sensitive parameter. An appropriate design of the gas chamber combined with a suitable flow-rate management can lead to improvements in the neutron production of one order of magnitude working in a fast repetitive mode.
Address [Tarifeno-Saldivia, Ariel; Soto, Leopoldo] Comis Chilena Energia Nucl CCHEN, Santiago, Chile, Email: atarisal@gmail.com;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0741-3335 ISBN Medium
Area Expedition Conference
Notes WOS:000346926300024 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2070
Permanent link to this record
 
 
Author Llosa, G.
Title Recent developments in photodetection for medical applications Type Journal Article
Year 2015 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 787 Issue Pages 353-357
Keywords Detectors; Photodetectors; Medical applications; PET; SPECT; Hadron Therapy
Abstract (down) The use of the most advanced technology in medical imaging results in the development of high performance detectors that can significantly improve the performance of the medical devices employed in hospitals. Scintillator crystals coupled to photodetectors remain to be essential detectors in terms of performance and cost for medical imaging applications in different imaging modalities. Recent advances in photodetectors result in an increase of the performance of the medical scanners. Solid state detectors can provide substantial performance improvement, but are more complex to integrate into clinical detectors due mainly to their higher cost. Solid state photodetectors (APDs, SiPMs) have made new detector concepts possible and have led to improvements in different imaging modalities. Recent advances in detectors for medical imaging are revised.
Address UVEG, CSIC, Inst Fis Corpuscular, Valencia, Spain, Email: gabriela.llosa@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000354869900079 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2233
Permanent link to this record
 
 
Author Viegas, R.; Roser, J.; Barrientos, L.; Borja-Lloret, M.; Casaña, J.V.; Lopez, J.G.; Jimenez-Ramos, M.C.; Hueso-Gonzalez, F.; Ros, A.; Llosa, G.
Title Characterization of a Compton camera based on the TOFPET2 ASIC Type Journal Article
Year 2023 Publication Radiation Physics and Chemistry Abbreviated Journal Radiat. Phys. Chem.
Volume 202 Issue Pages 110507 - 11pp
Keywords Compton camera; Hadron therapy; LaBr3; PETsys TOFPET2; Silicon photomultipliers
Abstract (down) The use of Compton cameras for medical imaging and its interest as a hadron therapy treatment monitoring has increased in the last decade with the development of silicon photomultipliers. MACACOp is a Compton camera prototype designed and assembled at the IRIS group of IFIC-Valencia. This Compton camera is based on monolithic Lanthanum (III) Bromide crystals and silicon photomultipliers, and employs the novel TOFPET2 ASIC as readout electronics. This system emerged as an alternative to MACACO II prototype, with the aim of improving its limited time resolution. To test the performance of the ASIC in a Compton camera setup, the prototype was characterized, both in laboratory and in-beam. A time resolution of 1.5 ns was obtained after time corrections, which improves greatly the performance of the MACACO II. Moreover, the results obtained at high photon energies demonstrate the ability of the system to obtain 1 mm displacements of the reconstructed spots. The results reinforce the potential of the system as a monitoring device for hadron therapy.
Address [Viegas, R.; Roser, J.; Barrientos, L.; Borja-Lloret, M.; Casana, J., V; Hueso-Gonzalez, F.; Ros, A.; Llosa, G.] CSIC UV, Inst Fis Corpuscular IFIC, Valencia, Spain, Email: Rita.Viegas@ific.uv.es
Corporate Author Thesis
Publisher Pergamon-Elsevier Science Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0969-806x ISBN Medium
Area Expedition Conference
Notes WOS:000870840600006 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5392
Permanent link to this record
 
 
Author Becker, R.; Buck, A.; Casella, C.; Dissertori, G.; Fischer, J.; Howard, A.; Ito, M.; Khateri, P.; Lustermann, W.; Oliver, J.F.; Roser, U.; Warnock, G.; Weber, B.
Title The SAFIR experiment: Concept, status and perspectives Type Journal Article
Year 2017 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 845 Issue Pages 648-651
Keywords Positron Emission Tomography (PET); Hybrid PET/MRI; SiPM
Abstract (down) The SAFIR development represents a novel Positron Emission Tomography (PET) detector, conceived for preclinical fast acquisitions inside the bore of a Magnetic Resonance Imaging (MRI) scanner. The goal is hybrid and simultaneous PET/MRI dynamic studies at unprecedented temporal resolutions of a few seconds. The detector relies on matrices of scintillating LSO-based crystals coupled one-to-one with SiPM arrays and readout by fast ASIC5 with excellent timing resolution and high rate capabilities. The paper describes the detector concept and the initial results in terms of simulations and characterisation measurements.
Address [Becker, Robert; Casella, Chiara; Dissertori, Gunther; Fischer, Jannis; Howard, Alexander; Ito, Mikiko; Khateri, Parisa; Lustermann, Werner; Roeser, Ulf] Swiss Fed Inst Technol, Inst Particle Phys, Zurich, Switzerland, Email: chiara.casella@cern.ch
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000394556300153 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2957
Permanent link to this record
 
 
Author Gomez-Cadenas, J.J.; Benlloch-Rodriguez, J.M.; Ferrario, P.; Monrabal, F.; Rodriguez, J.; Toledo, J.F.
Title Investigation of the coincidence resolving time performance of a PET scanner based on liquid xenon: a Monte Carlo study Type Journal Article
Year 2016 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 11 Issue Pages P09011 - 18pp
Keywords Gamma camera; SPECT; PET PET/CT; coronary CT angiography (CTA); Instrumentation and methods for time-of-flight (TOF) spectroscopy; Noble liquid detectors (scintillation ionization, double-phase); Scintillators; scintillation and light emission processes (solid, gas and liquid scintillators)
Abstract (down) The measurement of the time of flight of the two 511 keV gammas recorded in coincidence in a PET scanner provides an effective way of reducing the random background and therefore increases the scanner sensitivity, provided that the coincidence resolving time (CRT) of the gammas is sufficiently good. The best commercial PET-TOF system today (based in LYSO crystals and digital SiPMs), is the VEREOS of Philips, boasting a CRT of 316 ps (FWHM). In this paper we present a Monte Carlo investigation of the CRT performance of a PET scanner exploiting the scintillating properties of liquid xenon. We find that an excellent CRT of 70 ps (depending on the PDE of the sensor) can be obtained if the scanner is instrumented with silicon photomultipliers (SiPMs) sensitive to the ultraviolet light emitted by xenon. Alternatively, a CRT of 160 ps can be obtained instrumenting the scanner with (much cheaper) blue-sensitive SiPMs coated with a suitable wavelength shifter. These results show the excellent time of flight capabilities of a PET device based in liquid xenon.
Address [Gomez-Cadenas, J. J.; Benlloch-Rodriguez, J. M.; Ferrario, P.; Rodriguez, J.] CSIC, Inst Fis Corpuscular IFIC, Calle Catedrat Jose Beltran 2, Valencia 46980, Spain, Email: paola.ferrario@ific.uv.es
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000387862300011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2866
Permanent link to this record
 
 
Author Gillam, J.E.; Solevi, P.; Oliver, J.F.; Casella, C.; Heller, M.; Joram, C.; Rafecas, M.
Title Sensitivity recovery for the AX-PET prototype using inter-crystal scattering events Type Journal Article
Year 2014 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 59 Issue 15 Pages 4065-4083
Keywords positron emission tomography (PET); inter-crystal scattering; sensitivity
Abstract (down) The development of novel detection devices and systems such as the AX-positron emission tomography (PET) demonstrator often introduce or increase the measurement of atypical coincidence events such as inter-crystal scattering (ICS). In more standard systems, ICS events often go undetected and the small measured fraction may be ignored. As the measured quantity of such events in the data increases, so too does the importance of considering them during image reconstruction. Generally, treatment of ICS events will attempt to determine which of the possible candidate lines of response (LoRs) correctly determine the annihilation photon trajectory. However, methods of assessment often have low success rates or are computationally demanding. In this investigation alternative approaches are considered. Experimental data was taken using the AX-PET prototype and a NEMA phantom. Three methods of ICS treatment were assessed-each of which considered all possible candidate LoRs during image reconstruction. Maximum likelihood expectation maximization was used in conjunction with both standard (line-like) and novel (V-like in this investigation) detection responses modeled within the system matrix. The investigation assumed that no information other than interaction locations was available to distinguish between candidates, yet the methods assessed all provided means by which such information could be included. In all cases it was shown that the signal to noise ratio is increased using ICS events. However, only one method, which used full modeling of the ICS response in the system matrix-the V-like model-provided enhancement in all figures of merit assessed in this investigation. Finally, the optimal method of ICS incorporation was demonstrated using data from two small animals measured using the AX-PET demonstrator.
Address [Gillam, John E.; Solevi, Paola; Oliver, Josep F.; Rafecas, Magdalena] Univ Valencia, CSIC, IFIC, Valencia, Spain, Email: john.gillam@sydney.edu.au
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9155 ISBN Medium
Area Expedition Conference
Notes WOS:000340056800006 Approved no
Is ISI yes International Collaboration
Call Number IFIC @ pastor @ Serial 1879
Permanent link to this record
 
 
Author Bolle, E.; Casella, C.; Chesi, E.; De Leo, R.; Dissertori, G.; Fanti, V.; Gillam, J.E.; Heller, M.; Joram, C.; Lustermann, W.; Nappi, E.; Oliver, J.F.; Pauss, F.; Rafecas, M.; Rudge, A.; Ruotsalainen, U.; Schinzel, D.; Schneider, T.; Seguinot, J.; Solevi, P.; Stapnes, S.; Tuna, U.; Weilhammer, P.
Title AX-PET: A novel PET concept with G-APD readout Type Journal Article
Year 2012 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 695 Issue Pages 129-134
Keywords PET; Axial geometry; Geiger-mode Avalanche Photo Diodes (G-APD); SiPM
Abstract (down) The AX-PET collaboration has developed a novel concept for high resolution PET imaging to overcome some of the performance limitations of classical PET cameras, in particular the compromise between spatial resolution and sensitivity introduced by the parallax error. The detector consists of an arrangement of long LYSO scintillating crystals axially oriented around the field of view together with arrays of wave length shifter strips orthogonal to the crystals. This matrix allows a precise 3D measurement of the photon interaction point. This is valid both for photoelectric absorption at 511 key and for Compton scattering down to deposited energies of about 100 keV. Crystals and WLS strips are individually read out using Geiger-mode Avalanche Photo Diodes (G-APDs). The sensitivity of such a detector can be adjusted by changing the number of layers and the resolution is defined by the crystal and strip dimensions. Two AX-PET modules were built and fully characterized in dedicated test set-ups at CERN, with point-like Na-22 sources. Their performance in terms of energy (Renew approximate to 11.8% (FWMH) at 511 key) and spatial resolution was assessed (sigma(axial) approximate to 0.65 mm), both individually and for the two modules in coincidence. Test campaigns at ETH Zurich and at the company AAA allowed the tomographic reconstructions of more complex phantoms validating the 3D reconstruction algorithms. The concept of the AX-PET modules will be presented together with some characterization results. We describe a count rate model which allows to optimize the planing of the tomographic scans.
Address [Heller, M.; Joram, C.; Schneider, T.; Seguinot, J.] CERN, PH Dept, CH-1211 Geneva, Switzerland, Email: Matthieu.Heller@cern.ch
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000311469900026 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1236
Permanent link to this record