BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Preparation of laser-proton cell irradiation experiments at L2A2 DTSTART;VALUE=DATE-TIME:20201215T114500Z DTEND;VALUE=DATE-TIME:20201215T120000Z DTSTAMP;VALUE=DATE-TIME:20260811T021432Z UID:indico-contribution-1950-13915@indico.ific.uv.es DESCRIPTION:Speakers: Alberto Torralba Torregrosa ()\nUltra-short and ultr a-intense pulsed lasers allow for accelerating short bunches of protons an d ions to MeV-range energies. Our aim is to design and build an experiment al setup for the L2A2 laboratory\, at the University of Santiago de Compos tela\, for the study of radiobiological effects caused by laser-accelerate d protons on human cancer cell cultures. The Ti:Sapphire laser at L2A2 del ivers 1.2 J pulses at a rate of 10 Hz and peak power of 50 TW. The corresp onding focused intensity is sufficient for accelerating protons to 5-10 Me V through the Target Normal Sheath Acceleration mechanism (TNSA).\nThe bea m of accelerated protons/ions passes through a pinhole collimator followed by a sequence of permanent magnets that generate a configuration of antip arallel magnetic fields with the purpose of bending the trajectories of th e protons and separating them from electrons and photons originating from the laser-plasma interaction. In addition\, the magnetic fields act as an energy separator with a resulting\, lateral displacement of the protons de pending on their momentum. This allows for selecting a narrow range of ene rgies with approximately uniform dose deposition within the irradiated are a. This entire setup is located inside a vacuum chamber. The particles lea ve the chamber through a thin foil of kapton (polyimide) and finally impin ge on the cell culture outside the vacuum system. Cell cultures are prepar ed and analysed at the Fundación Pública Galega Medicina Xenómica and I DIS. The first trials will be centred around the quantification of DNA dou ble-strand breaks as a function of radiation dose.\nA major challenge of t his project is the precise measurement of the dose deposited by the laser- driven beams. For significant doses (up to 5 Gy)\, several shots have to b e accumulated. Shot-to-shot fluctuations of the proton flux impose the nec essity for online monitoring which is demanding in our range of energies. Furthermore\, the response of electronic detectors to ultra-high instantan eous rates will be studied in careful cross-calibration measurements with passive materials. The experiment is under construction and it is planned to be running in 2021.\n\nhttps://indico.ific.uv.es/event/5983/contributio ns/13915/ LOCATION:Virtuales URL:https://indico.ific.uv.es/event/5983/contributions/13915/ END:VEVENT BEGIN:VEVENT SUMMARY:TERMOGRAFÍA INFRARROJA: TÉCNICA DE IMAGEN ÚTIL EN PEDIATRÍA DTSTART;VALUE=DATE-TIME:20201215T121500Z DTEND;VALUE=DATE-TIME:20201215T123000Z DTSTAMP;VALUE=DATE-TIME:20260811T021432Z UID:indico-contribution-1950-13914@indico.ific.uv.es DESCRIPTION:Speakers: Olga Benavent Casanova (Departamento de Salud de la Ribera)\n**Introducción y objetivo**\nLa Termografía Infrarroja\, permit e registrar el mapa de temperaturas de la piel\, de manera inocua\, rápid a y sin contacto con el paciente. Detecta las asimetrías que se producen en la microcirculación cutánea cuando existen procesos inflamatorios\, i nfecciosos\, vasculares...que alteran su distribución. Por estas razones\ , su uso resultaría especialmente útil en población pediátrica\, y en patologías que alteran la vascularización periférica. El objetivo de es te trabajo es realizar una correlación descriptiva entre las imágenes ob tenidas mediante técnicas convencionales y mediante Termografía Infrarro ja en diferentes patologías pediátricas.\n\n**Material y métodos**\nSe realizó un estudio prospectivo descriptivo en 6 niños (2 anomalías vasc ulares\, 2 complicaciones de catéteres y 2 óseas) atendidos en el Hospit al Clínico Universitario de Valencia. Se realizaron los controles rutinar ios y las técnicas de imagen convencionales cuando estaban indicadas\, y además se complementó la valoración con imágenes termográficas. El re gistro de las imágenes termográficas se realizó con cámara Flir E60\, siguiendo el protocolo estándar\, adaptado a población pediátrica. Los parámetros termográficos fueron: emisividad: 0\,98\, distancia: 1 metro\ , temperatura ambiente: 24°C y humedad ambiente: 50%. El análisis de las imágenes se realizó con el programa ThermaCAMResearcher Pro 2.10\, dete rminando temperatura media (TM)\, máxima (Tmáx) y mínima (Tmín) de las regiones de interés (ROIs): zona afecta\, sana y referencia (frente). Se realizó valoración cualitativa de las imágenes termográficas y cuanti tativa\, mediante el cálculo de un Índice Térmico ((IT= (TM ROIafecta – TM ROIsana/TM frente) x 100)\n\n**Resultados**\nEn las imágenes termo gráficas se apreció cualitativamente y cuantitativamente (IT) asimetría térmica entre la zona patológica y la contralateral sana\, mayor al dia gnóstico que tras la administración de tratamiento\, cuando la evolució n fue favorable. Las imágenes termográficas se correlacionaron con las p ruebas complementarias rutinarias y con la evolución clínica del pacient e. Ejemplos de hemangioma infantil en Figura 1 y de celulitis de catéter de derivación ventrículo-peritoneal en Figura 2.\n\n**Conclusiones**\nLa Termografía Infrarroja aporta información relevante para el diagnóstic o y seguimiento de pacientes pediátricos con patologías que alteran la v ascularización periférica\, ya que es capaz de identificar incluso halla zgos que pasan inadvertidos en la exploración clínica\, y detectar cambi os en la microcirculación cutánea no detectables mediante pruebas conven cionales.\n\nhttps://indico.ific.uv.es/event/5983/contributions/13914/ LOCATION:Virtuales URL:https://indico.ific.uv.es/event/5983/contributions/13914/ END:VEVENT BEGIN:VEVENT SUMMARY:Complete characterization of the energy spectra of laser-accelerat ed protons for the production of radioisotopes used in medical imaging. DTSTART;VALUE=DATE-TIME:20201215T120000Z DTEND;VALUE=DATE-TIME:20201215T121500Z DTSTAMP;VALUE=DATE-TIME:20260811T021432Z UID:indico-contribution-1950-13906@indico.ific.uv.es DESCRIPTION:Speakers: Juan Peñas Nadales (Universidade de Santiago de Com postela)\nLaser-driven ion accelerators may represent a competitive techno logy for the future production of medical radioisotopes. First experiments on laser-driven proton acceleration in the Target Normal Sheath Accelerat ion (TNSA) regime were performed at the Laser Laboratory for Acceleration and Applications (L2A2) by focusing a 45 TW\, 10 Hz repetition rate femtos econd laser on Al foils of a few micrometer thickness. Typical exponential maxwellian-like proton spectra with a cut-off energy up to 1.65 MeV were measured with a time-of-flight (ToF) detector system. Results have been co mpared to recently published data\, regarding maximum energy\, particle nu mber\, and distribution temperature in order to infer correlations between these parameters and the laser pulses characteristics. These correlations were used to extrapolate our results to obtain estimations on production activities for various proton- and deuteron-induced nuclear reactions\, fo r optimized experimental parameters. Activity levels of ~32.1 MBq for 11C via 11B(p\;n)11C reaction are estimated for one hour of irradiation at a l aser repetition rate of 10 Hz\, which are in the range of doses required f or preclinical Positron Emission Tomography (PET) imaging. Other radioisot ope production reactions are also considered and studied.\n\nhttps://indic o.ific.uv.es/event/5983/contributions/13906/ LOCATION:Virtuales URL:https://indico.ific.uv.es/event/5983/contributions/13906/ END:VEVENT BEGIN:VEVENT SUMMARY:Simultaneous imaging of hard and soft biological tissues in a low- field MRI scanner DTSTART;VALUE=DATE-TIME:20201215T113000Z DTEND;VALUE=DATE-TIME:20201215T114500Z DTSTAMP;VALUE=DATE-TIME:20260811T021432Z UID:indico-contribution-1950-13904@indico.ific.uv.es DESCRIPTION:Speakers: José Miguel Algarín (MRILab\, I3M\, CSIC and Unive rsitat Politècnica de València Valencia)\n**INTRODUCTION**\nHere we pres ent “DentMRI – Gen I” (Fig. 1(a))\, a home-made special-purpose MRI scanner designed with the goal of demonstrating dental imaging at low fiel d (260 mT). We use two variations of zero echo time (ZTE) pulse sequences (Fig. 1(b)): standard PETRA [1\,2]\, and Double Radial Non Stop Spin Echo (DRaNSSE)\, which we have devised to address limitations we encounter with PETRA. We perform image reconstruction by Algebraic Reconstruction Techni ques (ART\, [3]).\n\n**METHODS**\n“DentMRI – Gen I” operates with a “C”-shaped permanent NdFeB magnet that provides 260 mT over a spherica l region of 150 mm in diameter. The system is equipped with a gradient sys tem capable of reaching strengths > 0.4 T/m along any spatial direction an d a TxRx RF solenoid coil able to induce a flip angle of 90 degrees in a f ew microseconds.\n\n**RESULTS**\nFigure 2(c) contains selected slices from the full 3D ART reconstruction of a rabbit head employing a PETRA sequenc e with 0.5 mm isotropic resolution. We acquired two images: one with a sho rt (90 µs) dead time (Fig. 3(c) top) with a scan time of 61 minutes\; and one with a long (1 ms) dead time (Fig. 2(c) middle) with a scan time of 3 1 minutes. The bottom image in Fig. 3(c) shows difference between both ima ges to highlight hard tissues.\nFigure 3 shows ART reconstructions slices from DRaNSSE (top) and PETRA (bottom) acquisitions. Images were acquired w ith 1 mm isotropic resolution with a total scan time of 30 (15) minutes fo r DRaNSSE (PETRA). Due to the long echo time for the second echo (10 ms)\, tissue contrast is higher with DRaNSSE.\n\n**DISCUSSION/CONCLUSION**\nIn the present work we have demonstrated the capability of our new low-cost “DentMRI – Gen I” scanner to simultaneously image hard and soft biol ogical tissues\; we have devised a new pulse sequence (DRaNSSE) that\, com pared to standard sequences such as PETRA\, yields higher SNR images and e nhanced tissue contrast.\n\n**ACKNOWLEDGMENT**\nThis work was supported by the European Commission under Grants 737180 (FET-OPEN: HISTO-MRI) and 481 (ATTRACT: DentMRI). S. Aja-Fernández acknowledges Ministerio de Ciencia e Innovación of Spain for Research grant RTI2018-094569-B-I00\n\n**REFERE NCES**\n[1] M. Weiger\, K. P. Pruessmann\, A.-K. Bracher\, S. Köhler\, V. Lehmann\, U. Wolfram\, F. Hennel\, and V. Rasche\, “High-resolution ZTE imaging of human teeth\,” NMR in Biomedicine\, vol. 25\, no. 10\, pp. 1 144–1151\, oct 2012. [Online]. Available: http://doi.wiley.com/10.1002/n bm.2783\n\n[2] D. M. Grodzki\, P. M. Jakob\, and B. Heismann\, “Ultrasho rt echo time imaging using pointwise encoding time reduction with radial a cquisition (PETRA)\,” Magnetic Resonance in Medicine\, vol. 67\, no. 2\, pp. 510–518\, feb 2012.\n\n[3] R. M. Gower and P. Richtarik\, “Random ized iterative methods for linear systems\,” SIAM Journal on Matrix Anal ysis and Applications\, vol. 36\, no. 4\, pp. 1660–1690\, 2015.\n\nhttps ://indico.ific.uv.es/event/5983/contributions/13904/ LOCATION:Virtuales URL:https://indico.ific.uv.es/event/5983/contributions/13904/ END:VEVENT BEGIN:VEVENT SUMMARY:Hologramas acústicos bilaterales para terapia transcraneal DTSTART;VALUE=DATE-TIME:20201215T111500Z DTEND;VALUE=DATE-TIME:20201215T113000Z DTSTAMP;VALUE=DATE-TIME:20260811T021432Z UID:indico-contribution-1950-13903@indico.ific.uv.es DESCRIPTION:Speakers: Diana Andrés Bautista (Universitat Politècnica de València)\nEn los últimos años se ha demostrado la utilidad de la aplic ación de los ultrasonidos focalizados en el interior del cerebro con fina lidades terapéuticas. Mediante la ablación térmica se han desarrollado tratamientos para el temblor esencial y el Parkinson\, mientras que a inte nsidades moderadas se emplean para neuromodulación y apertura de la barre ra hematoencefálica\, permitiendo administrar fármacos de una forma no i nvasiva\, localizada y reversible. No obstante\, el haz de ultrasonidos su fre aberraciones en su camino hacia el sistema nervioso central (SNC) debi do a la atenuación y dispersión que introduce el cráneo. Además\, las estructuras cerebrales presentan una forma y distribución compleja a la q ue se debe adaptar el haz ultrasónico.\n\nHemos diseñado hologramas acú sticos impresos en 3D para compensar las aberraciones introducidas por el cráneo y dirigir el haz ultrasónico hacia dianas terapéuticas bilateral es en el SNC\, concretamente hacia el putamen\, núcleo caudado e hipocamp o\, cuya forma y tamaño se ha obtenido con imágenes MRI. Hemos empleado un cráneo exvivo (varón\, 73 años) del cual sabemos sus propiedades med iante una imagen TAC. Los hologramas se diseñan haciendo uso de la simetr ía de inversión temporal de las ecuaciones que dominan la propagación d e ondas acústicas y empleando fuentes virtuales que siguen la forma de es tructuras a tratar\, utilizando métodos numéricos pseudoespectrales. La información holográfica se registra en la ubicación del transductor y s e diseñan lentes de solo fase basadas en resonadores Fabry-Perot\, utiliz ando métodos de conjugación de fase. Las mismas se imprimen en 3D median te estereolitografía de fotopolímeros.\n\nLos experimentos se han realiz ado en un tanque de agua\, con un transductor ultrasónico focalizado de 1 00 mm de apertura y 140 mm de focal\, con una frecuencia central de 500 kH z. Para posicionar la lente holográfica respecto del cráneo de forma que la localización coincida con la de las simulaciones y además asegurar q ue la posición del cráneo permanezca constante a lo largo de las medidas \, se ha diseñado e impreso un soporte. Las medidas se han realizado con un hidrófono de aguja con una sensibilidad de -228 dB ref. 1V/µPa.\n\nSe ha simulado el campo acústico generado por las lentes diseñadas para la s tres estructuras bilaterales en el interior del cerebro. De media\, el v olumen tratado ha sido de un 24 % del volumen total\, mientras que con el foco natural del transductor solo trataríamos un 5%. Las ganancias han si do de 3.5 p/p0\, donde p0 es la presión en la superficie del transductor\ , mientras que sin usar lente es de 6.8 p/p0. Los experimentos ex vivo con las lentes impresas 3D han demostrado un completo acuerdo con los valores obtenidos mediante simulaciones numéricas.\n\nEn conclusión\, los holog ramas pueden usarse para diseñar sistemas robustos y económicos para foc alizar los ultrasonidos en estructuras complejas en el interior del cerebr o para neuromodulación y la apertura de la barrera hematoencefálica.\n\n https://indico.ific.uv.es/event/5983/contributions/13903/ LOCATION:Virtuales URL:https://indico.ific.uv.es/event/5983/contributions/13903/ END:VEVENT BEGIN:VEVENT SUMMARY:Organ-dedicated high-performance PET developments at i3M DTSTART;VALUE=DATE-TIME:20201215T110000Z DTEND;VALUE=DATE-TIME:20201215T111500Z DTSTAMP;VALUE=DATE-TIME:20260811T021432Z UID:indico-contribution-1950-13902@indico.ific.uv.es DESCRIPTION:Speakers: Antonio J. Gonzalez (i3M (CSIC-UPV))\nPositron Emiss ion Tomography (PET) systems have significantly evolved in the last decade with the access to new photosensor technology such as Silicon Photomultip liers (SiPM) and novel readout electronics enabling the possibility to acc urately determine the Coincidence Timing Resolution (CTR) of the two annih ilation photons. \n\nThere has been a large effort into the so-called Tota l-Body PET (TB-PET) imaging for humans. That means\, PET systems with a ve ry large axial coverage\, in one case up to 2 meters long. This developmen t makes it possible to increase the system sensitivity a factor 40 compare d to 20-25 cm axial length of conventional whole-body PET systems. TB-PET also allows clinicians to perform multi-organ imaging. The non-negligible drawback of such TB-PET endeavors is their huge cost.\n\nAn alternative to increase the effective sensitivity is to improve the timing capabilities. For instance\, a CTR of 100 ps FWHM will boost this sensitivity by a fact or of 16. Moreover\, organ-dedicated systems exhibit higher overall perfor mance than WB or TB-PET due to their smaller geometries. I3M has developed several organ-dedicated PET systems\, recently including the capabilities to reach 240 ps CTR. In most of the systems monolithic crystal technology is used\, offering determination of the depth of interaction of the annih ilation event and\, thus\, allowing one to correct for the parallax error. \n\nIn this contribution we describe systems such as the breast dedicated MAMMI reaching 1.4 mm spatial resolution with few thousands of patients al ready scanned. Two new designs are ongoing\, one based on two-panels PET a nd another on an edgeless crystal geometry. We will also describe the brai n dedicated PET so-called MINDView that is also an insert\, that means MR compatible. This system uses the largest volume of monolithic crystals in a clinical PET scanner. A circular prostate-dedicated PET system was devel oped few years ago\, after the attempt of using novel geometries\, and tes ted at the neighboring largest hospital in our region. Our last developmen t is a heart PET system\, based on crystal arrays but reaching timing reso lutions below 240 ps CTR. Other novel designs will also be discussed.\n\nh ttps://indico.ific.uv.es/event/5983/contributions/13902/ LOCATION:Virtuales URL:https://indico.ific.uv.es/event/5983/contributions/13902/ END:VEVENT END:VCALENDAR