Benlloch Baviera, Jose María

Organizational Units

Organizational Unit

Instituto de Instrumentación para Imagen Molecular

ORCID

0000-0001-6073-1436

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https://www.upv.es/ficha-personal/jobenba

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Now showing 1 - 10 of 11

Scanner calibration of a small animal PET camera based on continuous LSO crystals and flat panel PSPMTs
(Elsevier, 2007-02-01) Benlloch Baviera, Jose María; Carrilero, V.; González Martínez, Antonio Javier; Catret, J.; Lerche, Christoph Werner; Abellan, D.; García de Quiros, F.; Gimenez, M.; Modia, J.; Sánchez, Filomeno; Ros García, Ana; Martínez, J.; Sebastia Cortes, Angel; Instituto de Instrumentación para Imagen Molecular
[EN] We have constructed a small animal PET with four identical detector modules, each consisting of a continuous LYSO crystal attached to a Position Sensitive Photomultiplier Tube (PSPMT). The dimensions of the continuous crystal are 50 x 50 mm 2 and 10 mm thickness. The modules are separated 11 cm between each other in the scanner. In this paper we discuss the method used for the calibration of the camera for this special system with continuous detectors. We also present the preliminary values for the main performance parameters such as spatial and energy resolution, and sensitivity of the system. (c) 2006 Elsevier B.V. All rights reserved.
Retroreflector arrays for better light collection efficiency of γ-ray imaging detectors with continuous scintillation crystals without DOI misestimation
(IOP Publishing, 2014-04) Ros, A.; Lerche, Christoph Werner; Sebastia Cortes, Angel; Sanchez, F.; Benlloch Baviera, Jose María; Instituto de Instrumentación para Imagen Molecular
A method to improve light collection efficiency of γ-ray imaging detectors by using retroreflector arrays has been tested, simulations of the behaviour of the scintillation light illuminating the retroreflector surface have been made. Measurements including retroreflector arrays in the setup have also been taken. For the measurements, positron emission tomography (PET) detectors with continuous scintillation crystals have been used. Each detector module consists of a continuous LSO-scintillator of dimensions 49x49x10 mm3 and a H8500 position-sensitive photomultiplier (PSPMT) from Hamamatsu. By using a continuous scintillation crystal, the scintillation light distribution has not been destroyed and the energy, the centroids along the x- and y-direction and the depth of interaction (DOI) can be estimated. Simulations have also been run taking into account the use of continuous scintillation crystals. Due to the geometry of the continuous scintillation crystals in comparison with pixelated crystals, a good light collection efficiency is necessary to correctly reconstruct the impact point of the γ-ray. The aim of this study is to investigate whether micro-machine retro-reflectors improve light yield without misestimation of the impact point. The results shows an improvement on the energy and centroid resolutions without worsening the depth of interaction resolution. Therefore it can be concluded that using retroreflector arrays at the entrance side of the scintillation crystal improves light collection efficiency without worsening the impact point estimation.
PET detector block with accurate 4D capabilities
(Elsevier, 2018-12-21) Lamprou, Efthymios; Aguilar -Talens, Albert; Gonzalez-Montoro, Andrea; Monzó Ferrer, José María; Cañizares-Ledo, Gabriel; Iranzo-Egea, Sofía; Vidal San Sebastián, Luis Fernando; Hernández Hernández, Liczandro; Conde-Castellanos, Pablo Eloy; Sánchez-Góez, Sebastián; Sánchez Martínez, Filomeno; González Martínez, Antonio Javier; Benlloch Baviera, Jose María; Departamento de Ingeniería Electrónica; Escuela Técnica Superior de Ingeniería de Telecomunicación; Instituto de Instrumentación para Imagen Molecular; European Commission; Ministerio de Economía y Competitividad
[EN] In this contribution, large SiPM arrays (8 x 8 elements of 6 x 6 mm(2) each) are processed with an ASIC-based readout and coupled to a monolithic LYSO crystal to explore their potential use for TOF-PET applications. The aim of this work is to study the integration of this technology in the development of clinical PET systems reaching sub-300 ps coincidence resolving time (CRT). The SiPM and readout electronics have been evaluated first, using a small size 1.6 mm (6 mm height) crystal array (32 x 32 elements). All pixels were well resolved and they exhibited an energy resolution of about 20% (using Time-over-Threshold methods) for the 511 keV photons. Several parameters have been scanned to achieve the optimum readout system performance, obtaining a CRT as good as 330 +/- 5 ps FWHM. When using a black-painted monolithic block, the spatial resolution was measured to be on average 2.6 +/- 0.5 mm, without correcting for the source size. Energy resolution appears to be slightly above 20%. CRT measurements with the monolithic crystal detector were also carried out. Preliminary results as well as calibration methods specifically designed to improve timing performance, are being analyzed in the present manuscript.
Design of the PET–MR system for head imaging of the DREAM Project
(Elsevier, 2013-02-21) González Martínez, Antonio Javier; Conde, P.; Hernández Hernández, Liczandro; Herrero Bosch, Vicente; Moliner Martínez, Laura; Monzó Ferrer, José María; Orero Palomares, Abel; Peiró Cloquell, Antonio; Rodríguez-Alvarez, M.J.; Ros García, Ana; Sánchez Martínez, Filomeno; Soriano Asensi, Antonio; Vidal San Sebastián, Luis Fernando; Benlloch Baviera, Jose María; Departamento de Ingeniería Electrónica; Escuela Técnica Superior de Ingeniería de Telecomunicación; Instituto de Instrumentación para Imagen Molecular; Generalitat Valenciana
In this paper we describe the overall design of a PET–MR system for head imaging within the framework of the DREAM Project as well as the first detector module tests. The PET system design consists of 4 rings of 16 detector modules each and it is expected to be integrated in a head dedicated radio frequency coil of an MR scanner. The PET modules are based on monolithic LYSO crystals coupled by means of optical devices to an array of 256 Silicon Photomultipliers. These types of crystals allow to preserve the scintillation light distribution and, thus, to recover the exact photon impact position with the proper characterization of such a distribution. Every module contains 4 Application Specific Integrated Circuits (ASICs) which return detailed information of several light statistical momenta. The preliminary tests carried out on this design and controlled by means of ASICs have shown promising results towards the suitability of hybrid PET–MR systems.
Metascintillators: New Results for TOF-PET Applications
(Institute of Electrical and Electronics Engineers, 2022-05) Lecoq, Paul; Konstantinou, Georgios; Latella, Riccardo; Moliner Martínez, Laura; Nuyts, Johan; Zhang, Lei; Barrio Toala, John; Benlloch Baviera, Jose María; González Martínez, Antonio Javier; Departamento de Ingeniería Electrónica; Escuela Técnica Superior de Ingeniería de Telecomunicación; Instituto de Instrumentación para Imagen Molecular; European Commission; European Research Council
[EN] We report on the progress on a first generation of realistic size metascintillators for time-of-flight PET. These heterostructures combine dense LYSO or BGO plates, interleaved with fast scintillator layers producing a bunch of prompt photons from the energy leakage of the recoil photoelectric electron. From a Geant4 simulation of the energy sharing distribution between the dense and the fast scintillator on 42 LYSO-based and 42 BGO-based configurations, a detailed study of the timing performance has been performed on a selection of the most promising 12 LYSO-based and 14 BGO-based metascintillators. A Monte Carlo simulation was first performed to extrapolate from direct measurements of the performance of the metascintillator components, the detector time resolution (DTR), and sensitivity on the basis of the simulated amount of energy leakage to the fast scintillator. An analytic algorithm was then applied to determine an equivalent coincidence time resolution (CTR) from the random association of the DTR distributions from two metapixels in coincidence. This equivalent CTR is calculated in order to obtain the same variance in the reconstructed image as the combination of the DTR distributions of 2 metapixels. Preliminary results confirm that with these simple and still nonoptimized configurations, an equivalent CTR of 150 ps for BGO-based and 140 ps for LYSO-based metapixels of realistic size can be obtained
PETIROC2 based readout electronics optimization for Gamma Cameras and PET detectors
(IOP Publishing, 2017) Monzó Ferrer, José María; Aguilar -Talens, Albert; González Montoro, Andrea; Lamprou,E.; González Martínez, Antonio Javier; Hernández Hernández, Liczandro; Mázur, Dmytro; Colom Palero, Ricardo José; Benlloch Baviera, Jose María; Departamento de Ingeniería Electrónica; Escuela Técnica Superior de Ingeniería de Telecomunicación; Instituto de Instrumentación para Imagen Molecular; Ministerio de Economía, Industria y Competitividad
[EN] Developing front-end electronics to improve charge detection and time resolution in gamma-ray detectors is one of the main tasks to improve performance in new multimodal imaging systems that merge information of Magnetic Resonance Imaging and Gamma Camera or PET tomographs. The aim of this work is to study the behaviour and to optimize the performance of an ASIC for PET and Gamma Camera applications based on SiPMs detectors. PETIROC2 is a commercial ASIC developed by Weeroc to provide accurate charge and time coincidence resolutions. It has 32 analog input channels that are independently managed. Each channel is divided into two signals, one for time stamping using a TDC and another for charge measurement. In this work, PETIROC2 is evaluated in an experimental setup composed of two pixelated LYSO crystals based detectors, each coupled to a Hamamatsu 4 x 4 SiPM array. Both detectors are working in coincidence with a separation distance between them that can be modified. In the present work, an energy resolution of 13 : 6% FWHM and a time coincidence resolution of 815 ps FWHM have been obtained. These results will be useful to optimize and improve PETIROC2 based PET and Gamma Camera systems.
Small animal PET scanner based on monolithic LYSO crystals: Performance evaluation
(American Association of Physicists in Medicine: Medical Physics, 2012) Sánchez Martínez, Filomeno; Moliner Martínez, Laura; Correcher, C.; González Martínez, Antonio Javier; Orero Palomares, Abel; Carles Fariña, Montserrat; Soriano Asensi, Antonio; Rodríguez Álvarez, María José; Medina, L.A; Mora Mas, Francisco José; Benlloch Baviera, Jose María; Departamento de Ingeniería Electrónica; Escuela Técnica Superior de Ingeniería de Telecomunicación; Departamento de Matemática Aplicada; Escuela Técnica Superior de Ingeniería Informática; Instituto de Instrumentación para Imagen Molecular; Ministerio de Ciencia e Innovación; Generalitat Valenciana
Purpose: The authors have developed a small animal Positron emission tomography(PET)scanner based on monolithic LYSO crystals coupled to multi-anode photomultiplier tubes (MA-PMTs). In this study, the authors report on the design, calibration procedure, and performance evaluation of a PET system that the authors have developed using this innovative nonpixelated detector design. Methods : The scanner is made up of eight compact modules forming an octagon with an axial field of view (FOV) of 40 mm and a transaxial FOV of 80 mm diameter. In order to fully determine its performance, a recently issued National Electrical Manufacturers Association (NEMA) NU-4 protocol, specifically developed for small animal PETscanners, has been followed. By measuring the width of light distribution collected in the MA-PMT the authors are able to determine depth of interaction (DOI), thus making the proper identification of lines of response (LORs) with large incidence angles possible. PET performances are compared with those obtained with currently commercially available small animal PETscanners. Results : At axial center when the point-like source is located at 5 mm from the radial center, the spatial resolution measured was 1.65, 1.80, and 1.86 mm full width at half maximum (FWHM) for radial, tangential, and axial image profiles, respectively. A system scatter fraction of 7.5% (mouse-like phantom) and 13% (rat-like phantom) was obtained, while the maximum noise equivalent count rate (NECR) was 16.9 kcps at 12.7 MBq (0.37 MBq/ml) for mouse-like phantom and 12.8 kcps at 12.4 MBq (0.042 MBq/ml) for rat-like phantom The peak absolute sensitivity in the center of the FOV is 2% for a 30% peak energy window. Several animal images are also presented. Conclusions: The overall performance of our small animal PET is comparable to that obtained with much more complex crystal pixelated PET systems. Moreover, the new proposed PET produces high-quality images suitable for studies with small animals.
Programmable integrated front-end for SiPM/PMT PET detectors with continuous scintillating crystal
(IOP Publishing: Hybrid Open Access, 2012-12) Herrero Bosch, Vicente; Monzó Ferrer, José María; Ros García, Ana; Aliaga Varea, Ramón José; González Martínez, Antonio Javier; Montoliu, C.; Colom Palero, Ricardo José; Benlloch Baviera, Jose María; Departamento de Ingeniería Electrónica; Escuela Técnica Superior de Ingeniería de Telecomunicación; Instituto Universitario de Matemática Pura y Aplicada; Instituto de Instrumentación para Imagen Molecular; Universitat Politècnica de València
[EN] AMIC architecture has been introduced in previous works in order to provide a generic and expandable solution for implementing large number of outputs SiPM array/PMT detectors. The underlying idea in AMIC architecture is to calculate the moments of the detected light distribution in an analog fashion. These moments provide information about energy, x/y position, etc. of the light distribution of the detected event. Moreover this means that a small set of signals contains most of the information of the event, thus reducing the number of channels to be acquired. This paper introduces a new front-end device AMIC2GR which implements the AMIC architecture improving the features of the former integrated devices. Higher bandwidth and filtering coefficient precision along with a lower noise allow to apply some detector enhancements. Inhomogeneity among detector elements throughout the array can be reduced. Depth of interaction measurements can be obtained from the light distribution analysis. Also a common trigger signal can be obtained for the whole detector array. Finally AMIC2GR preamplifier stage close to SiPM output signals optimizes signal to noise ratio, which allows to reduce SiPM gain by using lower operating voltages thus reducing dark noise
Position correction with depth of interaction information for a small animal PET system
(Elsevier, 2011) Carles, M.; Lerche, Christoph Werner; Sánchez Martínez, Filomeno; Mora Mas, Francisco José; Benlloch Baviera, Jose María; Departamento de Ingeniería Electrónica; Escuela Técnica Superior de Ingeniería de Telecomunicación; Instituto de Instrumentación para Imagen Molecular
[EN] In this work we study the effects on the spatial resolution when depth of interaction (001) information is included in the parameterization of the line of response (LOR) for a small animal positron emission tomography (PET) system. One of the most important degrading factors for PET is the parallax error introduced in systems that do not provide DOI information of the recorded gamma-rays. Our group has designed a simple and inexpensive method for DOI determination in continuous scintillation crystals. This method is based, on one hand, in the correlation between the scintillation light distribution width in monolithic crystals and the DOI, and, on the other hand, on a small modification of the widely applied charge dividing circuits (CDR). In this work we present a new system calibration that includes the DOI information, and also the development of the correction equations that relates the LOR without and with DOI information. We report the results obtained for different measurements along the transaxial field of view (FOV) and the image quality enhancement achieved specially at the edge of the FOV. (C) 2010 Elsevier B.V. All rights reserved.
A new brain dedicated PET scanner with 4D detector information
(Walter de Gruyter GmbH, 2022-12) González-Montoro, Andrea; Barbera Ballester, Julio; Sánchez Gonzalo, David; Mondejar, Álvaro; Freire-López-Fando, Marta; Díaz González, Karel; Lucero-Ruiz, Alejandro; Jiménez Serrano, Santiago; Alamo Valenzuela, Jorge; Morera Ballester, Constantino; Barrio Toala, John; Cucarella, Neus; Ilisie, Victor; Moliner Martínez, Laura; Valladares de-Francisco, Celia; González Martínez, Antonio Javier; John Prior; Benlloch Baviera, Jose María; Departamento de Ingeniería Electrónica; Escuela Técnica Superior de Ingeniería de Telecomunicación; Departamento de Sistemas Informáticos y Computación; Escuela Técnica Superior de Ingeniería Informática; Instituto de Instrumentación para Imagen Molecular; Generalitat Valenciana; European Research Council
[EN] In this article, we present the geometrical design and preliminary results of a high sensitivity organ-specific Positron Emission Tomography (PET) system dedicated to the study of the human brain. The system, called 4D-PET, will allow accurate imaging of brain studies due to its expected high sensitivity, high 3D spatial resolution and, by including precise photon time of flight (TOF) information, a boosted signal-to-noise ratio (SNR). The 4D-PET system incorporates an innovative detector design based on crystal slabs (semi-monolithic) that enables accurate 3D photon impact positioning (including photon Depth of Interaction (DOI) measurement), while providing a precise determination of the photon arrival time to the detector. The detector includes a novel readout system that reduces the number of detector signals in a ratio of 4:1 thus, alleviating complexity and cost. The analog output signals are fed to the TOFPET2 ASIC (PETsys) for scalability purposes. The present manuscript reports the evaluation of the 4D-PET detector, achieving best values 3D resolution values of <1.6 mm (pixelated axis), 2.7±0.5 mm (monolithic axis) and 3.4±1.1 (DOI axis) mm; 359 ± 7 ps coincidence time resolution (CTR); 10.2±1.5 % energy resolution; and sensitivity of 16.2% at the center of the scanner (simulated). Moreover, a comprehensive description of the 4D-PET architecture (that includes 320 detectors), some pictures of its mechanical assembly, and simulations on the expected image quality are provided.