Imaging 2016

Report of Abstracts

Imaging 2016 / Report of Abstracts Chaotic system based multi- . . .

Abstract ID : 1

Chaotic system based multi-layers security ofgray-scale image combined with RP2DFRFT and

Arnold transform

Content

With the increase in overall social networking based sharing of image data, security ofimage information has become more relevant and important today. We hereby, proposea new technique to encrypt and decrypt images (or any multimedia data) by means ofchaotic map based scrambling combined with reality preserving two dimensional discreteFractional Fourier Transform (RP2DFRFT) and Arnold Transform (AT). Earlier designedkey-based cryptosystems for image data provides single layer protection for the images. Butthe proposed technique provides multi-layered security to the image without loss of anysensitive information. The advantage of this technique is that in addition to the supply ofmore number of keys, it also requires cryptanalysts to have the knowledge of arrangement ofparameters. The employment of two scrambling techniques, one before and another after thedomain transform adds to the intricacies of the algorithm providing additional security.Theuse of reality preserving method not just eliminates the complexity of dealing with imaginarydata, but it also enhances the efficiency of the technique by reducing the domain space toits half, at least for all the calculations involved in two dimensional DFRFT. Results ofsecurity analysis and statistical analysis obtained on some standard images are testimonyto the robustness of the presented technique. This method would find a large applicationsin multimedia data processing and its security in regard to the transmission in less securenetwork.

Primary author(s) : Mr. SAURAV, Saurav (Indian School of Mines (ISM))

Co-author(s) : Mr. DEEPAK, D.c. Mishra (Indian Institute of Technology, Delhi); Prof.SHARMA, R.k. (Indian Institute of Technology, Delhi); Dr. AKHILESH, Akhilesh (IndianSchool of Mines, Dhanbad)

Presenter(s) : Mr. SAURAV, Saurav (Indian School of Mines (ISM))

Status: SUBMITTED

Submitted by SUMAN, Saurav on Wednesday 13 April 2016

June 12, 2016 Page 1

Imaging 2016 / Report of Abstracts Photon-counting x-ray imaging . . .

Abstract ID : 2

Photon-counting x-ray imaging of scoliosis

ContentBackground: Scoliosis is a medical condition where a spinal axis has a complex three-dimensional (3D) deformity. In the diagnosis, monitoring and management of scoliosis, imagesof the spine are required where imaging modalities such as radiography, computed tomography(CT) and magnetic resonance (MR) imaging are commonly used, where radiography playsthe primary role.In a two-dimensional (2D) radiographic image, scoliosis is quantified as a condition with aCobb angle larger than 10◦. When assessing the curve condition, the apical vertebra is firstidentified, which is the furthest deviated vertebra. The Cobb angle is defined as the anglebetween a line parallel to the upper end-plate of the most tilted vertebrea above the apicalvertebrea and a line parallel to the lower end-plate of the most tilted vertebra below theapical vertebra. The angle can be measured manually or digitally, and the methods havebeen found to be equally reliable. A total error of 2◦ – 7◦ can be expected in the Cobb angleassessment due to the variations in radiographic acquisitions and measurement error.Purpose: Adolescents are the high-risk group of scoliosis. Their high sensitivities to radiationdose therefore motivate a big amount of studies in optimizing and minimizing the radiationdose during the radiographic evaluation of scoliosis. However, protocols usually refer to theoptimization of the scan parameters, e.g. x-ray tube current and voltage, physical shield oradvanced image reconstruction techniques. In this work, we investigate the possibility of low-dose radiographic imaging of the spinal curve and accurate assessment of Cobb angle with theaid of x-ray photon-counting (PC) detectors since that advantages of photon-counting x-raydetectors have been shown such as the isolation from electronic noise by proper thresholdsetting and the reduction of radiation dose while maintaining an image quality comparableto an energy-integrating (EI) system in various imaging tasks.Method: In this work, a simulation model is built based on the Forbild thorax phantom.Instead of the normal spine that appears to be a straight line in the posteroanterior (PA) oranteroposterior (AP) radiograph, a C-shaped scoliotic spine is used in the thorax phantom.PA radiographs of the phantom are obtained both by the PC and the EI x-ray imagingsystems at different incident photon fluxes, in the other word, different dose levels. At eachdose level, radiography of the phantom is repeated 50 times for both systems to introducethe noise effects. For each obtained radiograph, an algorithm for automatic measurement ofCobb angle is applied. The measurement error of the Cobb angle is used as a figure-of-merit.Results: From 0.1 mGy, the measurement error of the Cobb angle from images obtained bythe PC system is lower than 2◦, whereas, the EI system comes to this point until 0.7 mGy.Even lower dose can be achieved by the PC system by applying energy-weighting schemes.

Primary author(s) : Ms. LIU, Xuejin (KTH Royal Institute of Technology)

Co-author(s) : Prof. DANIELSSON, Mats (KTH Royal Institute of Technology)

Presenter(s) : Ms. LIU, Xuejin (KTH Royal Institute of Technology)

Status: SUBMITTED

Submitted by LIU, Xuejin on Thursday 14 April 2016

June 12, 2016 Page 2

Imaging 2016 / Report of Abstracts Improvement of the performan� . . .

Abstract ID : 3

Improvement of the performance of broad energygermanium detectors using pulse shape analysis for

environmental applications

Content

The optimisation of High Purity Germanium (HPGe) detector performance for differentgamma-ray interactions is an active area of research in the field of nuclear physics. This goalrequires a theoretical study of the detector response from the simulation point of view andexperimental sets of measurements for validation. Consequently, simulations were used tomodel the response of a broad energy germanium (BEGe) detector, produced by Canberra,using unique pieces of software; MCNP4C, GAMOS and MATLAB for analyzing simulationoutputs. In routine sample counting, for instance, the gamma-ray energies are required to beexactly determined so the radionuclides within samples can be identified and quantified. Thedrawback of germanium detectors is their poor peak to Compton response that can makeachieving this objective difficult. This is because of the fact that Compton scattering effect isthe most probable interaction type within the detector for gamma-ray energies, which leadsto a significant Compton continuum in the measured energy spectrum at energies below thefull energy photo peak. Therefore, this work aims to increase the peak-to-Compton (P/C)ratios while maintaining both the excellent energy resolution and the detector efficiency.P/C ratio means the total number of events in the maximum channel of a photo peakdivided by the average of Compton background events per channel within a region whereCompton events are located. Increasing P/C ratio will result in an improvement in thedetector sensitivity. To achieve this, Digital Pulse Processing (DPP) techniques were appliedto gamma spectroscopy measurements, which focus on measuring and counting samples.DPP allowed pulse-shaping parameters to be optimised and pulse shapes to be recorded foroff-line analysis. Data from a digital acquisition (DAQ) system has been analysed by sets ofsort codes to produce spectra after the application of energy and rise time filters. SeveralFigures of Merit (FOM) were then constructed each considering a specific class of eventswhich is described as Compton escaped events, in an attempt to expand the proportionof the full energy events in the processed spectra. One of the figures was focusing on theforward scattering events, provided a remarkable improvement in the P/C values comparedto those for the original (or ungated) spectrum of all recorded events.

Primary author(s) : ALI, Najat (University of Liverpool)

Presenter(s) : ALI, Najat (University of Liverpool)

Comments:Dear/Madam/Sir;I am submitting the above abstract in response to the call for Imaging 2016 conferenceand am looking forward to participate in this conference along side my supervisor Dr.Andrew Boston which is one of the invited speakers in this conference.I am looking forward to hearing from you soonerNajat Ali a.ali@liv.ac.uk

June 12, 2016 Page 3

Imaging 2016 / Report of Abstracts Improvement of the performan� . . .

Status: SUBMITTED

Submitted by ALI, Najat on Monday 18 April 2016

June 12, 2016 Page 4

Imaging 2016 / Report of Abstracts X-ray astronomical imaging wi� . . .

Abstract ID : 4

X-ray astronomical imaging with emphasis on theAthena mission

Content

The Athena mission is the next large European effort in building X-ray observatories with aforeseen launch in 2028. The optical system is based on Silicon Pore Optics (SPO) with agoal to obtain an angular resolution of close to or better than 5”. The collecting area willbe around 2 sqm hence it reaches an unprecedented sensitivity in the 0.1 - 12 keV energyrange. The technology is reviewed with respect to surface preparation, assembly, and testing.The optical properties are analyzed using a raytracing code. Finally the science goals arediscussed.

Primary author(s) : Dr. WESTERGAARD, Niels Jørgen (Technical University of Denmark)

Co-author(s) : Dr. FERREIRA, Desiree D. M. (Technical University of Denmark); Dr.MASSAHI, Sonny (Technical University of Denmark)

Presenter(s) : Dr. WESTERGAARD, Niels Jørgen (Technical University of Denmark)

Comments:Invited presentation

Status: SUBMITTED

Submitted by JØRGEN WESTERGAARD, Niels on Wednesday 20 April 2016

June 12, 2016 Page 5

Imaging 2016 / Report of Abstracts Liquid-metal-jet X-ray tube tec� . . .

Abstract ID : 5

Liquid-metal-jet X-ray tube technology andtomography applications

ContentThe power and brightness of electron-impact micro-focus X-ray tubes have long been limitedby thermal damage in the anode. This limit is overcome by the liquid-metal-jet anode(MetalJet) technology that has previously demonstrated [1] brightness in the range of oneorder of magnitude above current state-of-the art sources. This is possible due to theregenerative nature of this anode and the fact that the anode is already molten, which allowsfor significantly higher e-beam power density than on conventional solid anodes.Over the last years, the MetalJet technology has developed from prototypes into fullyoperational and stable X-ray tubes running in many labs over the world. Key applicationsinclude X-ray diffraction and scattering, but recently several publications [2,3,4,5] have alsoshown very impressive X-ray computed tomography results using the liquid-metal-jet anodetechnology, especially in phase contrast imaging.This presentation will review the current status of the technology specifically in termsof stability, lifetime, flux and brightness, with a clear focus on its applicability for X-raycomputed tomography. It will also discuss details of the liquid-metal-jet technology with afocus on the fundamental limitations of the technology. It will furthermore refer to somerecent data from applications within X-ray computed tomography.[1] O. Hemberg, M. Otendal, and H. M. Hertz, Liquid-metal-jet anode electron-impact x-raysource, Applied Physics Letter, 2003, 83, 1483.[2] D. H. Larsson, U. Lundström, U. Westermark, P. A. C. Takman, A. Burvall, M. ArsenianHenriksson, H. M. Hertz, Small-animal tomography with a liquid-metal-jet x-ray source,SPIE Proceedings Vol. 8313 Medical Imaging 2012: Physics of Medical Imaging[3] S. Zabler, T. Ebensperger, C. Fella, R. Hanke, High-resolution X-ray imaging for lab-basedmaterials research, Conference on Industrial Computed Tomography, Wels, Austria 2012[4] T. Thüring, T. Zhou, U. Lundström, A. Burvall, S. Rutishauser, C. David, H. M. Hertz,M. Stampanoni, X-ray grating interferometry with a liquid-metal-jet source, Applied PhysicsLetters 103, 091105 (2013)[5] M. Bartels, V. H. Hernandez, M. Krenkel, T. Moser, T. Salditt, Phase contrast tomographyof the mouse cochlea at microfocus x-ray sources, Applied Physics Letters 103, 083703 (2013)

Primary author(s) : Dr. HANSSON, Björn (Excillum AB)

Presenter(s) : Dr. HANSSON, Björn (Excillum AB)

Status: SUBMITTED

Submitted by ESPES, Emil on Thursday 21 April 2016

June 12, 2016 Page 6

Imaging 2016 / Report of Abstracts Application of gamma imaging . . .

Abstract ID : 7

Application of gamma imaging techniques for thecharacterisation of position sensitive gamma

detectors

ContentGamma tracking arrays will be an essential tool for future gamma spectroscopy withrelativistic ion beams (e.g. AGATA [1] at FAIR [2]). Tracking the path of Comptonscattered gamma rays in such detector arrays relies on a precise knowledge of the detectorresponse in terms of the pulse shapes obtained from the preamplifiers. Thus, characterizationof the detector modules has to include setting up a database of pulse shapes obtainedeither experimentally or from simulations. Recent investigations [3] have revealed significantdifferences between simulated and measured pulse shapes implying the need for experimentallyobtained pulse shapes. However, with conventional collimator based detector scanningsystems [4,5] a full detector scan cannot be made on a reasonable timescale. For thisreason a detector scanning system has been realized at GSI that combines gamma imagingtechniques with sophisticated pulse shape analysis algorithms [6]. This novel scanning systemhas already been proven to work successful [7] and now we intend to carry out a detailedcomparison of its results with a similar scanning system at IPHC Strasbourg and pulseshapes obtained from a conventional scanning system to validate these new detector scanningsystems as an efficient and reliable alternative to simulations. The first step has been carriedout and we will report on the scan of a pixelated planar germanium detector with the GSIscanning system.[1] S. Akkoyun et al., Nuclear Instruments and Methods in Physics Research Section A,668:26–58, March 2012[2] P. Spiller,G. Franchetti, Nuclear Instruments and Methods in Physics Research SectionA, 561(2):305-309, June 2006[3] M. Ginsz, Characterisation of high purity, multi-segmented germanium detectors. PhDthesis, Université de Strasbourg, France, 2015[4] M.R. Dimmock et al., IEEE Transactions on Nuclear Science, 56(3):1593–1599, June 2009[5] T.M.H. Ha et al., Nuclear Instruments and Methods in Physics Research Section A,697:123–132, January 2013[6] C. Domingo-Pardo et al., Nuclear Instruments and Methods in Physics Research SectionA, 643(1):79-88, July 2011[7] N.Goel et al., Nuclear Instrumentation and Methods in Physics Research Section A,700:10-21, February 2013

Primary author(s) : HABERMANN, Tobias (TU Darmstadt)

Co-author(s) : GERL, Juergen (GSI); KOJOUHAROV, Ivan (GSI); PIETRALLA, Norbert(IKP, Technische Universität Darmstadt); DIDIERJEAN, Francois (IPHC); SCHAFFNER,Henning (GSI); DUCHÊNE, Gilbert (IPHC); SIGWARD, Marie-hélène (IPHC); FILLIGER,Michel (IPHC)

Presenter(s) : HABERMANN, Tobias (TU Darmstadt)

Status: SUBMITTED

June 12, 2016 Page 7

Imaging 2016 / Report of Abstracts Application of gamma imaging . . .

Submitted by HABERMANN, Tobias on Friday 22 April 2016

June 12, 2016 Page 8

Imaging 2016 / Report of Abstracts The Tynode: a new vacuum ele� . . .

Abstract ID : 8

The Tynode: a new vacuum electron multiplier for anew generation of particle detectors

Content

Within the ERC-Advanced MEMBrane project, we are developing a new generic detectorconcept based on vacuum electron multiplication. For this, we are exploring transmissiondynodes “tynodes”. After the impact of an energetic electron at one side of a tynode, amultiple of electrons is emitted at the other side. By stacking N tynodes with a multiplicationfactor M, a number of M**N electrons will leave the stack, sufficient to activate the circuitryof a pixel in a CMOS chip. The 2D position of the original single primary electron canbe measured precisely thanks to the granularity of the pixel chip, and the arrival time ofthis electron can be measured with ps time resolution. By capping the tynode stack with aphotocathode, a new photomultiplier is created with groundbreaking properties. We haveconstructed dynodes using MEMS technology, reaching a Transmission Secondary ElectronYield (TSEY) of 2.7. With Atomic Layer Deposited (ALD) MgO we expect to exceed aTSEY of 4. From such a tynode, we will develop a MEMS stacking method, integrated ontoa CMOS pixel chip, forming a monolithic detector.

Primary author(s) : VAN DER GRAAF, Harry (Nikhef National institute for subatomicphysics (NL))

Presenter(s) : VAN DER GRAAF, Harry (Nikhef National institute for subatomic physics(NL))

Status: SUBMITTED

Submitted by VAN DER GRAAF, Harry on Monday 25 April 2016

June 12, 2016 Page 9

Imaging 2016 / Report of Abstracts 3D Ultrasound Computer Tom� . . .

Abstract ID : 9

3D Ultrasound Computer Tomography: HardwareSetup, Reconstruction Methods and First Clinical

Results

ContentA promising candidate for improved imaging of breast cancer is ultrasound computertomography (USCT). Current experimental USCT systems are still focused in elevationdimension resulting in a large slice thickness, limited depth of field, loss of out-of-planereflections, and a large number of movement steps to acquire a stack of images. 3D USCTemitting and receiving spherical wave fronts overcomes these limitations. We built anoptimized 3D USCT with nearly isotropic 3D point spread function, realizing for the firsttime the full benefits of a 3D system.The imaging properties were evaluated with a dedicated phantom. The point-spread functioncould be shown to be nearly isotropic in 3D, to have very low spatial variability and fit thepredicted values of (0.24 mm)3. The contrast of the phantom images is very satisfactoryin spite of imaging with a sparse aperture. From the acquired signal data of approx.2000 ultrasound transducers, re[U+FB02]ectivity, attenuation and sound speed images arereconstructed. The resolution and imaged details of the reflectivity reconstruction arecomparable to a 3 Tesla MRI volume. The KIT 3D USCT was then tested in a pilot studyon ten patients. The primary goals of the pilot study were to test the USCT device, the dataacquisition protocols, the image reconstruction methods and the image fusion techniques ina clinical environment.To overcome the considerably different breast positioning in both imaging methods, an imageregistration and image fusion based on biomechanical modelling of the buoyancy effect andsurface-based re[U+FB01]nement was applied. The resulting images are promising: comparedwith the MRI ground truth, similar tissue structures can be identi[U+FB01]ed. Patientmotion effects could be quantified and corrected. While re[U+FB02]ection images depictstructures down to 1

4 mm, sound speed imaging and attenuation are promising candidatesfor distinguishing cancer from normal tissue by their reconstructed absolute value. The[U+FB01]rst in-vivo study was successfully completed with an average imaging time of eightminutes per breast and encourages a second in-vivo study with a considerably larger numberof patients and shorter imaging time of six minutes, which is currently ongoing. The datareconstruction time for a typical 3D volume could be shortened by GPUs and appropriateapproximations to about 16 minutes. Furthermore the overall resolution and contrast fortransmission tomography will be improved by hardware and software upgrades by a factorsix.

Primary author(s) : Prof. GEMMEKE, Hartmut (KIT)

Co-author(s) : Dr. HOPP, Torsten (KIT); Dr. KAISER, Clemens (Institute of ClinicalRadiology and Nuclear Medicine Mannheim); Mr. ZAPF, Michael (KIT); Dr. RUITER, NicoleV. (KIT)

Presenter(s) : Prof. GEMMEKE, Hartmut (KIT)

Status: SUBMITTED

June 12, 2016 Page 10

Imaging 2016 / Report of Abstracts 3D Ultrasound Computer Tom� . . .

Submitted by GEMMEKE, Hartmut on Monday 25 April 2016

June 12, 2016 Page 11

Imaging 2016 / Report of Abstracts Particle identification with Aer� . . .

Abstract ID : 10

Particle identification with Aerogel Ring ImagingCherenkov Detector in Belle II Spectrometer

Content

The Belle II spectrometer at SuperKEKB e+e- collider at KEK, Tsukuba, Japan will be usedto study rare decay of B and D mesons and tau leptons. To efficiently separate kaons frompions in the momentum range from 0.5 to 3.5 GeV/c, two dedicated particle identificationdevices are designed: Time-Of-Propagation in the barrel part and Aerogel Ring ImagingCherenkov detector (ARICH) in the forward endcap of the detector. The ARICH should fitin small space of thickness of 28 cm with a high longitudinal magnetic field of 1.5 T , neutronfluence of 1012 1 MeV equivalent n/cm2 and gamma radiation dose of 100 Gy. The RICHdetector in a proximity focusing configuration consists of an aerogel Cherenkov radiator, anexpansion volume and a photon detector. The key performance parameters are number ofdetected photons and single photon Cherenkov angle resolution. To increase the light yieldthe transparency of the aerogel tiles the production ratio have been extensively studied toreduce the Rayleigh scattering ratio. By combining two radiators with different refractiveindices in focusing configuration, the number of detected photons is increased withoutdegrading the resolution. The Hamamatsu Hybrid Avalanche Photo Detector (HAPD) wasselected as an efficient photo sensor, capable of detecting single photons in the high magneticfield. The sensor consist of an bi-alkali photo-cathode, from where the photo electronsare accelerated toward the segmented avalanche photo-diode. The single photon electricalsignals of about 35000 e- are registered by custom ASIC and Xilinx Spartan 6 FPGA frontend board at the backside of the sensor. More than 400 aerogel tiles have been producedand machined by a water jet into wedge shapes. The optical properties of the aerogel tilesas well as the quantum efficiency and the response of the 420 HAPD sensors to a short laserpulses have been measured before the installation of the components in the detector. In thenext months the ARICH detector will be measured by cosmic rays and integrated in thefinal Belle II spectrometer, which will start collecting the physics data in 2017. Based on theresults from the beam test, where we measured on average 12 photons per saturated trackwith the single photon resolution of 14 mrad and the detailed detector simulation we expectthat an efficient kaon identification with an efficiency of more than 98% at a rather low pionmisidentification probability of 2% over the entire range of interest. In the contribution thedesign, detector components, results from the beam tests and the expected performance willbe shown.

Primary author(s) : PESTOTNIK, Rok (Jozef Stefan Institute)

Presenter(s) : PESTOTNIK, Rok (Jozef Stefan Institute)

Comments:on behalf of the Aerogel ARICH group

Status: SUBMITTED

June 12, 2016 Page 12

Imaging 2016 / Report of Abstracts Particle identification with Aer� . . .

Submitted by PESTOTNIK, Rok on Monday 25 April 2016

June 12, 2016 Page 13

Imaging 2016 / Report of Abstracts Characterization of CRY-018 a� . . .

Abstract ID : 12

Characterization of CRY-018 and CRY-019monolithic scintillation crystals for SPECT and PET

applications

Content

During the last years advancements in imaging for nuclear medicine have been tied up to thegrowth and invention of new scintillation crystals. The purpose of this work is to investigatethe radiation detection properties of gamma imagers based on two by Crytur enterpriserecently released mixed rare earth silicate single crystals, CRY-018 (Yttrium-Silicon mixture)and CRY-019 (Lutetium-Silicon mixture). CRY-018 and CRY-019 are non hygroscopic,have short decay time and low refraction index and are therefore attractive for PET andSPECT detectors. The crystals have been manufactured in a cylindrical shape of diameter52.0 ± 0.1 mm and thickness 6.25 ± 0.05 mm, in order to match the geometry of twonewly developed flat panel multi anode PMT-HAMAMATSU H12700A (BA) and H10966A(SBA). Both crystals were coated with a 0.2 mm TiO white paint, used as reflector. Opticalgrease (produced by “DOW CORNING CORPORATION” Mod. Q2-3067) was used forthe optical coupling and black tape was used to cover the crystals. H12700A (BA) andH10966A (SBA) have the same metal channel dynodic structure but respectively with 10and 8 dynodic stages, which lead to different gains at the same supply voltage. They alsodiffer from their first dynode collection efficiency: BA has the highest one between all thePS-PMT, while SBA got the highest quantum efficiency between his class of PMTs (at 420nm 35%). Mashing-up of these properties allowed to obtain similar statistical componentsof the total energy resolution. In order to evaluate pulse height linearity response, energyresolution and intrinsic detection efficiencies, for the CRY-018 and CRY-019 based gammadetectors described above, a series of radioactive point sources (22Na, 60Co, 57Co, 137Cs,133Ba, 241Am) with emission energy in the range from 60 keV to 1.4 MeV have been used.To simulate a narrow collimation at all energies, detector response was measured in a Regionof Interest (ROI) chosen in the central part of the crystal surfaces, exploiting the imagereconstruction properties of the MA-PMTs and the of the read out electronics used thatwas able to record the signal from all of the 64 PS-PMT channels independently. CRY-018and CRY-019 showed deviations from the pulse height linearity response respectively lowerthan the 1.5% for energies higher than 60 keV and lower than the 1% for energies higherthan 122 keV. As far as concerned the overall energy resolution, values are similar to thoseobtained, by us, with the R6231-01 PMT, which are of about 17% at 122 keV and 10.5%at 511 keV for CRY-018 while they are of about 20% at 122 keV and 13.5% at 511 keV forCRY-019. Intrinsic detection efficiency values, of about 37% at 122 keV and 5% at 511 keVfor CRY-018 and 80% at 122 keV and 20% at 511 keV for CRY-019, confirmed what wasemerged about suitability of CRY-018 for SPECT and CRY-019 for both PET and SPECTapplications. Preliminary measurements showed a very good intrinsic spatial resolutionbetter than 1.5 mm for both crystals. This is slightly worse than what obtained with thesame crystals coupled to a R6231-01 because of the poorer PMT statistic energy resolution.Our conclusion is that CRY-018 and CRY-019 have highly competitive performance forgamma imaging.

June 12, 2016 Page 14

Imaging 2016 / Report of Abstracts Characterization of CRY-018 a� . . .

Primary author(s) : Mr. PANI, Renato (Department of Physics, Sapienza University, Rome,Italy)

Co-author(s) : Prof. COLARIETI-TOSTI, Massimiliano (Department of Medical Engineering,School of Technology and Health, KTH Royal Institute of Technology and Karolinska Institutet,Department of Clinical Sciences, Intervention and Technology (Clintec), Division of MedicalImaging and Technology, Stockholm, Sweden); Ms. TRIGILA, Carlotta (Department of Physics,University of Rome ’Roma Tre’, Rome, Italy); Ms. POLITO, Claudia (Morphogenesis andtissue Engineering, Curriculum in cell and tissue Biophysics, Doctorate School of Biology andMolecular Medicine - SAIMLAL Department, Sapienza University, Rome, Italy); Dr. FABBRI,Andrea (Department of Physics and I.N.F.N., University of Rome ’Roma Tre’, Rome, Italy); Dr.BENNATI, Paolo (Department of Medical Engineering, School of Technology and Health, KTHRoyal Institute of Technology, Stockholm, Sweden); Mr. KARLSSON, Mattias (KarolinskaInstitutet, Department of Clinical Sciences, Intervention and Technology (Clintec), Division ofMedical Imaging and Technology, Stockholm, Sweden)

Presenter(s) : Mr. PANI, Renato (Department of Physics, Sapienza University, Rome,Italy); Ms. TRIGILA, Carlotta (Department of Physics, University of Rome ’Roma Tre’, Rome,Italy)

Status: SUBMITTED

Submitted by PANI, Renato on Monday 25 April 2016

June 12, 2016 Page 15

Imaging 2016 / Report of Abstracts New model for PET/CT image . . .

Abstract ID : 13

New model for PET/CT image processing andradiotherapy planning based on dose painting.

ContentIntroduction: Dose Painting (DP) is a radiotherapy treatment strategy for delivering a non-uniform dose distribution with a prescription based on the new concept of biological targetvolumes (BTVs) from medical images. Two approaches are being evaluated: threshold-baseddose painting by contours (DPBC), and voxel-based dose painting by numbers (DPBN).The study of the impact of different developed PET image reconstruction protocols on thesegmentation of the BTVs for DPBC, and the generation of the dose prescription maps forDPBN are topics under study in processing image for nuclear medicine and radiotherapy.Purpose: To present a new model for assessing the effect on the radiotherapy treatmentplanning of using different acquisition and reconstruction protocols for morpho-functionalimage from PET/CT before incorporating their use in the clinical routine.Material and methods: We used Siemens Biograph mCT PET/CT clinical scannerwith Syngo V51C acquisition software. Acquisition and reconstruction methods for EARL(ResEARch for Life R©, http://earl.eanm.org) [18F]FDG-PET/CT accreditation were carriedout and a protocol for maximize Recovery Coefficient (RC) in Image Quality NEMA 2007phantom was also implemented. The scanner and software apart from typical correctionsallows Time of Flight correction, iterative OSEM reconstruction and application of PointSpread Function. Beyond the deviations already observed between dose prescriptions mapsand the different reconstructed SUV images, in order to assess the impact of differentreconstruction methods on the treatment planning algorithm, actual clinical cases should bealso planned for both a dose painting by contours (DPBC) and a dose painting by numbers(DPBN) strategy. However, as far as we know, planning of DPBN is not supported bycommercial treatment planning system. To make possible this evaluation, a novel algorithmhas been developed for planning based on inverse planning, including an optimization methodat the voxel level, so restriction of dose to volumes from a previous segmentation processin the image is not necessary. The software was implemented in our in-house platformCARMEN, based on Matlab (http://grupos.us.es/medicalphysics/) for radiotherapy research.New image processing methods for generating the previous maps to the optimization processand new metrics for the evaluation of results were implemented in CARMEN platform. Theplatform was developed for the easy implementation of new algorithms under evaluationand then, to be applied to imported clinical cases.Results: The different reconstruction methods for the generation of prescription dose mapsfor DPBN and different semiautomatic segmentation algorithms for DBPN showed relevantdiscrepancies in covering tumor and unwished doses in healthy tissue and organs at risk.These results evidenced the need to incorporate standard protocols in the processing ofPET/CT images for radiotherapy planning.Conclusions: A new model was presented for the correct evaluation of the influence inthe radiotherapy planning of the implementation of different reconstruction methods andthresholds of morpho-functional information by PET/CT image processing.Topics: PET and SPECT, Computed Tomography

Primary author(s) : Ms. JIMENEZ-ORTEGA, Elisa (Dpto. de Fisiología Médica y Biofísica,Facultad de Medicina. Universidad de Sevilla, Sevilla, Spain.); Dr. UREBA, Ana (Dpto. deFisiología Médica y Biofísica, Facultad de Medicina. Universidad de Sevilla, Sevilla, Spain.); Dr.

June 12, 2016 Page 16

Imaging 2016 / Report of Abstracts New model for PET/CT image . . .

BALCERZYK, Marcin (Centro Nacional de Aceleradores (Universidad de Sevilla – CSIC –Junta de Andalucía), Sevilla, Spain.); Dr. FERNANDEZ-MAZA, Laura (Centro Nacionalde Aceleradores (Universidad de Sevilla – CSIC – Junta de Andalucía), Sevilla, Spain.); Mr.PARRADO-GALLEGO, Angel (Centro Nacional de Aceleradores (Universidad de Sevilla – CSIC– Junta de Andalucía), Sevilla, Spain.); Mr. HEVILLA, Juan (SIEMENS S. A Health CareEspaña); Mr. BAEZA, Jose Antonio (Dpto. de Fisiología Médica y Biofísica, Facultad deMedicina. Universidad de Sevilla, Sevilla, Spain.); Ms. VARGAS, Alejandra (Dpto. de FisiologíaMédica y Biofísica, Facultad de Medicina. Universidad de Sevilla, Sevilla, Spain.); Prof. LEAL,Antonio (Dpto. de Fisiología Médica y Biofísica, Facultad de Medicina. Universidad de Sevilla,Sevilla, Spain.)

Presenter(s) : Prof. LEAL, Antonio (Dpto. de Fisiología Médica y Biofísica, Facultad deMedicina. Universidad de Sevilla, Sevilla, Spain.)

Status: SUBMITTED

Submitted by LEAL, Antonio on Monday 25 April 2016

June 12, 2016 Page 17

Imaging 2016 / Report of Abstracts Application of EARL (ResEAR� . . .

Abstract ID : 14

Application of EARL (ResEARch 4 Life R©) approvedand rejected protocols for [18F]FDG-PET/CT

clinical and research studies.

ContentIn adjusting the available acquisition and reconstruction protocols to EARL (ResEARch 4Life R©, http://earl.eanm.org) [18F]FDG-PET/CT accreditation we also tried to developa protocol which maximises Recovery Coefficient (RC) for Image Quality NEMA 2007phantom. We used Siemens Biograph mCT PET/CT clinical scanner with Syngo V51Cacquisition software. The scanner and software apart from typical corrections allows Time ofFlight correction, iterative OSEM reconstruction and application of Point Spread Function.The protocol fulfilling EARL requirements was developed and also the research protocoloptimizing RC for mean Standard Uptake Value (SUV) and maximum SUV being as closeto 1 as possible for both SUV types simultaneously and for NEMA 2007 phantom spheres of17 mm diameter and larger.For all developed protocols we assessed the differences in mean and maximum SUV forsmall diameter and low metabolic rate tumours in several clinical cases. Additionally, weevaluated the differences in other tumour parameters derived from VOI and ROI delineationlike dimensions and volume. An estimation of predictive value by using EARL accreditationprotocol facing the research protocol is being carried out.Topics: PET and SPECT, Computed Tomography.

Primary author(s) : Dr. BALCERZYK, Marcin (Centro Nacional de Aceleradores (Univer-sidad de Sevilla – CSIC – Junta de Andalucía), Sevilla, Spain.); Ms. FERNÁNDEZ-LÓPEZ,Rosa (Department of Nuclear Medicine, Universitary Hospital Virgen del Rocío, Avda. ManuelSiurot s/n, Seville, Spain); Mr. PARRADO-GALLEGO, Angel (Centro Nacional de Aceleradores(Universidad de Sevilla – CSIC – Junta de Andalucía), Sevilla, Spain.); Mr. CHAVERO ROYAN,José (Centro Nacional de Aceleradores (Universidad de Sevilla – CSIC – Junta de Andalucía),Sevilla, Spain. / Facultad de Física, Universidad de Sevilla, Sevilla, Spain.); Mr. HEVILLA, Juan(SIEMENS S. A Health Care España); Ms. JIMENEZ-ORTEGA, Elisa (Dpto. de FisiologíaMédica y Biofísica, Facultad de Medicina. Universidad de Sevilla, Sevilla, Spain.); Prof. LEAL,Plaza (Dpto. de Fisiología Médica y Biofísica, Facultad de Medicina. Universidad de Sevilla,Sevilla, Spain.)

Presenter(s) : Prof. LEAL, Plaza (Dpto. de Fisiología Médica y Biofísica, Facultad deMedicina. Universidad de Sevilla, Sevilla, Spain.)

Status: SUBMITTED

Submitted by LEAL, Antonio on Monday 25 April 2016

June 12, 2016 Page 18

Imaging 2016 / Report of Abstracts Performance and imaging capa� . . .

Abstract ID : 15

Performance and imaging capabilities of the DEGAShigh-resolution gamma-ray detector array for the

DESPEC experiment at FAIR

Content

The DESPEC (DEcay SPECtroscopy) experiment, which is part of the NUSTAR programme(NUclear Structure, Astrophysics and Reactions) at FAIR (Facility for Antiproton and IonResearch), will be devoted to investigate nuclear structure far from stability by means of theirground-state and isomeric decays. A key instrument in the setup will be the high-resolutionGe detector system (DEGAS, DEspec Ge Array Spectrometer) which is based on gamma-raytracking and imaging concepts for selecting rare decays in a vast background of radiationfrom different sources. DEGAS will be developed in three different phases; a first onebased on a re-arrangement of the existing EUROBALL cluster configuration earlier used atRISING/GSI and currently at EURICA/RIBF; a second one aiming for a “first-order imagingarray” profiting from the inherent imaging capabilities of AGATA-type detectors and a thirdlong-term phase involving, in addition, detectors with enhanced position sensitivity. Thepossibility to include a Ge Double Sided Strip Detector as an active implantation detectorfor improved imaging capability of the system, is also under study.

Primary author(s) : Dr. DONCEL, Maria (University of Liverpool)

Co-author(s) : Prof. CEDERWALL, Bo (Royal Institute of Technology); Dr. GADEA,Andrés (IFIC; CSIC); Dr. GERL, Juergen (GSI); Prof. PALIT, Rudrajyoti (Tata Instituteof Fundamental Research); Dr. KOHOUHAROV, Ivan (GSI); Dr. QUINTANA, Begona(University of Salamanca)

Presenter(s) : Dr. DONCEL, Maria (University of Liverpool)

Status: SUBMITTED

Submitted by DONCEL, Maria on Monday 25 April 2016

June 12, 2016 Page 19

Imaging 2016 / Report of Abstracts XIPE (the X-ray Imaging Pola� . . .

Abstract ID : 16

XIPE (the X-ray Imaging Polarimetry Explorer):opening a new window in the X-ray sky

Content

X-ray polarimetry allows for answering, in a novel way, to questions related to the accelerationphenomena in PWNe, Supernovae and Blazars, to the transport of radiation in plasmaembedded in a strong magnetic field like in pulsating X-ray binaries, to questions related tothe scattering in a-spherical geometries, like in AGNs and in the molecular clouds locatedin the galactic center region and, finally, to questions of fundamental physics. Since thedawn of X-ray astronomy it has been clear the value of polarimetry in this energy rangebut the available techniques have always been the major limitation. Modern photoelectricX-ray polarimeters, based on the Gas Pixel Detector (GPD) technologies, overcame theselimitations allowing for a sensitive measurement on hundreds of sources. XIPE (the X-ray Imaging Polarimetry Explorer) now in the study phase for ESA will be operated asa conventional X-ray observatory but providing polarimetry simultaneously to the usualimaging, temporal and spectral information. This is made possible by its unique payloadconfiguration consisting of three GPDs at the focus of three large, albeit low-weight, X-raytelescopes and fitting in the Vega launcher. In this talk I will review the major aspectsinvolved with this kind of measurement, the scientific targets, the mission profile and payloadof upcoming opportunities.

Primary author(s) : SOFFITTA, Paolo (IAPS/INAF)

Presenter(s) : SOFFITTA, Paolo (IAPS/INAF)

Status: SUBMITTED

Submitted by SOFFITTA, Paolo on Monday 25 April 2016

June 12, 2016 Page 20

Imaging 2016 / Report of Abstracts Superresolution x-ray imaging . . .

Abstract ID : 17

Superresolution x-ray imaging of blood vessels

ContentSpatial resolution is one of the most important properties of x-ray detectors. In contrastto digital cameras, where the pixel size improves rapidly over time, the pixel size used incomputed tomography (CT) scanners has been nearly constant at 1 mm for two decades.Developing smaller detectors, without drawbacks such as decreased dose efficiency, is tech-nically difficult. However, using an energy-resolving photon-counting detector, there is away to use the spectral distribution of the x-ray photons to obtain spatial information on asub-pixel scale, using the so-called nonlinear partial volume (NLPV) effect.It is a common approximation to assume that the linear attenuation coefficient as a functionof energy µ(E) is a linear combination of two basis functions for all elements present in humantissue. If a k-edge contrast agent such as iodine is present in the imaged volume, the linearattenuation coefficient of that substance must be added as a third basis function. However,due to the NLPV effect, which is a result of the exponential form of x-ray attenuation, thelow-dimensionality assumption is violated near sharp interfaces parallel to the beam. Thisallows a spectral CT system with three or more energy levels to generate an NLPV imagewhere only sharp transitions are visible, allowing the user to differentiate between abruptand gradual transitions. This is a form of super-resolution imaging in the sense that spatialinformation on a smaller scale than the pixel size can be obtained.We calculate the signal-difference-to-noise ratio (SDNR) for different blood vessel diametersand iodine concentrations in order to determine the necessary dose for distinguishing betweensharp and gradual transitions. The robustness of the method when the interface length alongthe beam, the steepness of the interface and the pixel location relative to the interface isvaried is studied in a simulation study for an ideal photon-counting detector. The feasibilityof reconstructing a CT image from NLPV projection images is investigated in a simulationstudy.Results show that for a 10 mm long section along the blood vessel, the threshold for detectingthe NLPV component at the interface (defined as an SDNR of 5 after summing slices) isattained for a tube-current product of 170 mAs for a carotid artery imaging case and for200 mAs for an aorta imaging case, for 0.5 mm pixel width, 120 kVp and 40 mg/ml iodine.The method is relatively robust to alterations in the interface geometry.We also demonstrate the that the method works experimentally, using a photon-countingsilicon strip detector with eight energy bins. A 6 mm hole with 200 mg/ml iodine solutionembedded in a 120 mm polyethylene cylinder is imaged in a projection geometry and anNLPV image is generated, showing the locations of the hole interfaces.The technique has potential to improve visualization of small details in blood vessel wallssuch as dissections, aneurysms and ruptured plaques, thereby improving diagnosis andclinical outcome in acute stroke care.

Primary author(s) : PERSSON, Mats (KTH Royal Institute of Technology, Stockholm,Sweden)

Co-author(s) : Prof. HOLMIN, Staffan (Department of Clinical Neuroscience, KarolinskaInstitutet, Stockholm, Sweden and Department of Neuroradiology, Karolinska University HospitalSolna, Stockholm, Sweden); Mr. KARLSSON, Staffan (KTH Royal Institute Of Technology,Stockholm, Sweden); Prof. DANIELSSON, Mats (KTH Royal Institute of Technology, Stockholm,Sweden)

June 12, 2016 Page 21

Imaging 2016 / Report of Abstracts Superresolution x-ray imaging . . .

Presenter(s) : PERSSON, Mats (KTH Royal Institute of Technology, Stockholm, Sweden)

Comments:Part of the presented material, including the experimental study, will be submitted forjournal peer review before the conference. However, the SDNR investigation, the studyof sensitivity to model errors and the CT image simulation study are not publishedbefore.

Status: SUBMITTED

Submitted by PERSSON, Mats on Monday 25 April 2016

June 12, 2016 Page 22

Imaging 2016 / Report of Abstracts A SLIT-SCANNING SYSTEM . . .

Abstract ID : 18

A SLIT-SCANNING SYSTEM FORPHOTON-COUNTING BREAST

TOMOSYNTHESIS

ContentDigital breast tomosynthesis (DBT) is an x-ray imaging modality that has the potential toimprove both mammography screening and diagnostics. By acquiring multiple projectionsfrom a limited angular range it is possible to reconstruct a 3D volume with limited depthresolution. The most common method for doing DBT uses a fixed or tilt-able flat paneldetector with an x-ray tube scanning in an arc across the breast support. An alternativemethod uses a slit-scanning geometry with multiple collimated detector lines, which movessynchronously with the x-ray tube. A slit-scanning geometry have several benefits overflat-panel systems, including efficient scatter rejection by pre- and post-object collimators,no source motion blur thanks to synchronous source-detector movement, and physical spacefor more advanced detector systems for each line, such as edge-on silicon strip detectors formulti-threshold photon-counting. Using photon-counting detectors, each projection can beobtained with lower dose since the absence of electronic noise results in dose-independentquantum efficiency. In addition, photon-counting detector enable spectral imaging withapplications in, for instance, tissue characterization.We have previously developed prototypes for slit-scanning tomosynthesis, which utilizeda rotational geometry with the detector and source moving on a curved trajectory. Onechallenge of that implementation is that the imaging volume is curved, which is impracticalfor breast imaging tasks, and a relatively large portion of the imaging volume is shaved offwhen using a flat breast support. In addition to the reduction in imaging volume, spatialresolution is reduced at the edges of the image field because the detector moves further awayfrom the object. Other studies have demonstrated purely linear slit-scanning tomosynthesis,which results in a rectangular imaging volume and solves these challenges. A purely linearscan does, however, reduce the tomographic angle, which depends on the angular differencefrom the scanning motion in addition to the angle between the outermost detector lines.In the present study we report on the development of a novel slit-scanning geometry, whichemploys a combination of linear motion and rotation, hence maintaining rotation of thedetector and the accompanying increase in tomographic angle, while keeping the detectortranslation on a flat trajectory to generate a rectangular imaging volume. We present thedesign of the system, a framework for characterization of image quality, and example imagesfrom a prototype system.Our implementation of slit-scanning tomosynthesis does not generate projection imagesbecause 1) each line of the photon-counting detector is made up by a sparse array of sensorsand a combination of the line images is necessary to have an image without gaps, and 2) eachline image contains data from a range of source positions and is therefore not an image in theconventional sense. This makes projection bases image quality metrics unfeasible. Instead,we propose to use SBP (simple back-projection) reconstruction, which is unfiltered and canbe considered linear within small signal differences, to measure the traditional image-qualitymetrics of MTF, NPS and DQE. Measurements on the prototype system found the 50%MTF (the frequency at which the MTF has dropped to 0.5) in standard position at thebreast support to be 2.2 lp/mm in the scanning direction and 3.0 lp/mm in the slit direction.The zero-frequency value of the DQE was found to be 0.76.SBP is well-suited to estimate image-quality properties of the detector but creates strongblurring along the rays and thus mainly between slices. Depth resolution was thereforecharacterized using the clinical reconstruction and processing (iterative ART – algebraic

June 12, 2016 Page 23

Imaging 2016 / Report of Abstracts A SLIT-SCANNING SYSTEM . . .

reconstruction technique) and the artifact spread function (ASF) as a figure of merit. Thefull-width at half maximum of the ASF was found to be 3.6 mm.

Primary author(s) : BERGGREN, Karl (KTH Royal Institute of Technology)

Co-author(s) : Mr. FREDENBERG, Erik (Philips Health Systems); Mr. CEDERSTRÖM,Björn (Philips Health Systems); Mr. HJÄRN, Torbjörn (Philips Health Systems)

Presenter(s) : BERGGREN, Karl (KTH Royal Institute of Technology)

Status: SUBMITTED

Submitted by BERGGREN, Karl on Monday 25 April 2016

June 12, 2016 Page 24

Imaging 2016 / Report of Abstracts Capacitance estimation of a se� . . .

Abstract ID : 19

Capacitance estimation of a segmented silicon stripdetector

ContentCapacitance is a dominating factor in photon-counting x-ray detectors to ensure a lownoise level. We have developed a novel segmented silicon strip detector for photon-countingspectral CT. The sensor is 0.5 mm thick and 20 mm wide, and is divided into 50 strips witha strip width of 0.4 mm. A pixel size of 0.5×0.4 mm2 is formed by orienting the detector inedge-on geometry. Each detector strip is further divided into 9 segments to overcome highfluxes in x-ray CT imaging. This paper presents the results of capacitance simulation for3 diodes on the developed sensor and the comparison to measurements. The 3 diodes arethe second diode and the last diode in the second segment and the third diode in the lastsegment.The capacitance of each investigated diode was simulated by using Agilent ADS. Whenestimating the capacitance of a diode, all other components in the layout were connectedto ground plane except the measured one and its associated components, e.g. the routingwires and the corresponding ASIC input pad, and a single-ended port was added to themeasured diode. Two equivalent circuit models, Cs-Rs and Cp-Rp, were used to extract thecapacitance by assuming a parasitic resistance is in series or in parallel to the measuredcapacitance.The Cp-Rp model shows flatter frequency response and removes the low frequency artefactssignificantly. The capacitances of 1.411, 1.168 and 3.533 pF were obtained for the 3investigated diodes, in good agreement with the measured values of 1.433, 1.233 and 3.574pF, respectively, as well as the measured noise levels.

Primary author(s) : Dr. XU, Cheng (Royal Institute of Technology)

Co-author(s) : Prof. SVENSSON, Christer (Linköping University); Mr. KARLSSON, Staffan(Royal Institute of Technology); Prof. DANIELSSON, Mats (Royal Institute of Technology)

Presenter(s) : Dr. XU, Cheng (Royal Institute of Technology)

Status: SUBMITTED

Submitted by XU, Cheng on Tuesday 26 April 2016

June 12, 2016 Page 25

Imaging 2016 / Report of Abstracts RADIATION IMAGING WIT� . . .

Abstract ID : 20

RADIATION IMAGING WITH GASEOUSDETECTORS

Content

Developed primarily to meet the requirements of modern particle physics experiments, andwidely used in this field, the new class of devices collectively named Micro-pattern GaseousDetectors (MPGD) offer high rate and accurate localization performances that make theiruse attractive for application in other fields: medicine, biology, astrophysics. Robust andeasily manufactured up to sensitive areas of square meters, their design can be adapted toserve as position-sensitive detectors for charged particles, X- and Gamma-rays, neutrons.Recording of the interactions can be obtained with electronic readout systems and renderedon a screen, or directly recorded with optical sensors exploiting the scintillation of thesuitably chosen filling gases. This approach is particularly attractive for applications wherea real-time imaging of the radiation field is required. After a short survey of the MPGDperformances, I will discuss examples of the use of the technology for portal imaging, plasmadiagnostics, dose monitoring in hadrotherapy, fluorescence analysis, crystal diffraction.

Primary author(s) : Dr. SAULI, Fabio (CERN)

Presenter(s) : Dr. SAULI, Fabio (CERN)

Status: SUBMITTED

Submitted by SAULI, Fabio on Thursday 28 April 2016

June 12, 2016 Page 26

Imaging 2016 / Report of Abstracts Color Sensitive Silicon Photom� . . .

Abstract ID : 21

Color Sensitive Silicon Photomultiplier withmicro-cell level encoding for Crystal Identification of

PET detector

Content

Depth of Interaction (DOI) is important for high resolution PET system. Crystal Identifica-tion based wavelength was proposed recently. Also crystal identification is important formany radiation imaging system, such as Compton camera. A novel color sensitive SiPM(cSiPM) was designed and fabricated using micro-cell level encoding and color filtering withSiPM fabrication technology. The fabricated cSiPM has two outputs in one pixel of 2 mm x2 mm. The size of micro-cell is 30 µm x 30 µm and 2048 cells are connected for each output.2 of 4 micro-cell lines are connected and filtered with different color (Blue/Green, Blue/Redetc) and the pitch of different output is 60 µm. The thickness of deposited filter is 1.8 µm andthat of glass is 1 mm. The fabricated cSiPM was tested coupled with a stacked scintillator ofLYSO (2 x 2 x 10 mm) and GAGG (2 x 2 x 6 mm) with different peak wavelength (420 nmand 520 nm). The pulse height of two color outputs are sampled and digitized to calculatethe ratio. The ratio of two color outputs indicate the position of crystals and two crystalsare clearly separated with this method. The more detail characteristic and applications ofcSiPM will be presented at the conference.

Primary author(s) : SHIMAZOE, Kenji (The University of Tokyo)

Co-author(s) : Prof. TAKAHASHI, Hiroyuki (The University of Tokyo); GANKA, Thomas(KETEK GmbH); Dr. ISKRA, Peter (KETEK GmbH); Dr. SECO, Alicia (KETEK GmbH); Dr.SCHENEIDER, Florian (KETEK GmbH); Dr. WIEST, Florian (KETEK GmbH)

Presenter(s) : SHIMAZOE, Kenji (The University of Tokyo)

Status: SUBMITTED

Submitted by SHIMAZOE, Kenji on Thursday 05 May 2016

June 12, 2016 Page 27

Imaging 2016 / Report of Abstracts Evaluation of Double Photon . . .

Abstract ID : 23

Evaluation of Double Photon Coincidence ComptonImaging method with Geant4 Simulation

ContentCompton cameras have been used for various applications including astronomical observations,radioactive waste management, and medical imaging. They have advantages over mechanicalcollimation imaging system in wide field of view (FOV), suppression of background, andhigh detection efficiency, etc. Compton cameras use the kinematics of Compton scatteringto determine the incident angular of gamma rays. The source position is identified in theintersection of multiple cone traces through a large number of events.We explore a new approach for double photon coincidence Compton imaging method forincreasing signal to noise ratio (SNR). The target of this imaging method is a certain typeof nuclide that emits several gamma rays at the same time (Co-60, Cs-134, In-111, etc). Thesource position is confined in the intersection of two cones, which can reduce artifacts of thecone traces and enhance the SNR and angular resolution. In this paper, the comparison ofthe new double photon coincidence Compton imaging method and normal Compton imagingmethod was investigated by using GEANT4 Monte Carlo simulation.In the normal Compton imaging method, a gamma ray is scattered inelastically in the firstdetector plane (scatter), and absorbed in the second plane (absorber). If the gamma raydeposited all the energy to the two planes, its incident direction is confined on the conewith the specific angular defined by Compton scattering equation. In the double photoncoincidence Compton imaging method, two gamma rays are detected by two independentCompton cameras at the same time. Hence, the nuclide position is confined in the intersectionof the two cones. The geometry used for the simulation was a 6-ring Compton imagingsystem with a 60 mm axial extent and 100 mm diameter transaxial FOV. The scatter is50-layer stacked silicon strip detector with a sensitive area of 50×50 mm2 and the thicknessof 500 mm. Each detector layer has 48-channel readout strips with the width of 5 mm thatare arranged with the space of 5 mm. The absorber consists of 10×10 CdZnTe arrays witheach sensitive volume of 5×5×10 mm3. The distance between each scatter and absorberis 30 mm. A point source of In-111 was put in the center of the ring. The 2-D images fornormal/double photon coincidence Compton events were reconstructed by using a filter backprojection (FBP) method.The angular resolution and SNR of the normal Compton imaging method were 6.16 degreesFWHM and 14.8. On the contrary, the double photon coincidence Compton imaging methodshowed the angular resolution of 3.25 degrees FWHM and the SNR of 69.6. SNR wascalculated as the ratio of the average of bins’ value inside/outside of FWHM.

Primary author(s) : Ms. YOSHIHARA, Yuri (Department of Nuclear Engineering andManagement, The University of Tokyo)

Co-author(s) : Dr. SHIMAZOE, Kenji (Department of Nuclear Engineering and Management,The University of Tokyo); Prof. TAKAHASHI, Hiroyuki (Department of Nuclear Engineeringand Management, The University of Tokyo)

Presenter(s) : Ms. YOSHIHARA, Yuri (Department of Nuclear Engineering and Management,The University of Tokyo)

June 12, 2016 Page 28

Imaging 2016 / Report of Abstracts Evaluation of Double Photon . . .

Status: SUBMITTED

Submitted by YOSHIHARA, Yuri on Saturday 07 May 2016

June 12, 2016 Page 29

Imaging 2016 / Report of Abstracts Speckle-based x-ray phase- . . .

Abstract ID : 24

Speckle-based x-ray phase-contrast imaging using alaboratory system

ContentX-ray phase-contrast imaging has seen rapid development in the last decades. Interest is stillon the rise due to its higher sensitivity for low-Z materials and small structures, especiallyin the hard x-ray regime, compared to conventional absorption imaging. Many differentphase-contrast methods have been developed, among which speckle-based phase-contrastimaging (SBI) has drawn increased attention recently [1, 2]. For SBI a thin object withrandom structures, such as sandpaper, biological membrane, etc., can be used as a diffuserto generate a near-field speckle pattern. When a sample in the beam disturbs the specklepattern, this disturbance can be modeled as the total effect of attenuation of intensity,displacement of speckle pattern and loss of intensity contrast. By tracking those changes, itis possible to simultaneously retrieve the absorption, differential phase shift and so-calleddark-field images. This process can be done using either cross correlation or the least-squaresmethod. Here we present our work of applying different SBI techniques on a laboratorysystem using a liquid-metal-jet source [3-5]. The single-shot speckle-tracking technique isapplied directly on speckle images with and without sample [4]. To retrieve the displacementof one pixel, a subset window including some adjacent pixels is normally used to obtainsufficient data for the correlation analysis. This means that the spatial resolution is limitedby the window size. The Speckle scanning technique [6] uses multiple images, steppingthe diffuser in one or two dimensions similarly to the grating-based phase-contrast imagingmethod [7, 8]. The phase retrieval process is done on the intensity map of one pixel from allthe scan positions with and without sample. This allows for higher resolution, limited bythe scan step size rather than the speckle size. Applying SBI, the spatial resolution can beflexibly tuned to adapt to different applications by using different techniques. Depending onwhich technique is chosen, scan steps or correlation window size can be tuned for furtheradjustment. The geometrical magnification of the imaging system can be modified and thediffuser material chosen to generate speckles of a suitable size. SBI can also be implementedwith tomography [3], whereby the complex index of refraction of the sample material can beretrieved. With its good compatibility with broadband laboratory sources, cost efficiency,flexibility and ability in generating multimodal and quantitative results, SBI has the potentialfor a wide range of applications including metrology, biomedical imaging, material science,etc.

1. K. S. Morgan, D. M. Paganin, and K. K. W. Siu, Appl. Phys. Lett. 100, 124102(2012).

2. S. Berujon, H. C. Wang, and K. Sawhney, Phys. Rev. A 86, 063813 (2012).

3. I. Zanette, M. C. Zdora, T. Zhou, A. Burvall, D. H. Larsson, P. Thibault, H. M. Hertz,and F. Pfeiffer, Proc. Natl. Acad. Sci. U. S. A. 112, 12569 (2015).

4. I. Zanette, T. Zhou, A. Burvall, U. Lundstrom, D. H. Larsson, M. Zdora, P. Thibault,F. Pfeiffer, and H. M. Hertz, Phys. Rev. Lett. 112, 253903 (2014).

5. T. Zhou, I. Zanette, M. C. Zdora, U. Lundstrom, D. H. Larsson, H. M. Hertz, F.Pfeiffer, and A. Burvall, Opt. Lett. 40, 2822 (2015).

6. T. Weitkamp, A. Diaz, C. David, F. Pfeiffer, M. Stampanoni, P. Cloetens, and E.Ziegler, Opt. Express 13, 6296 (2005).

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Imaging 2016 / Report of Abstracts Speckle-based x-ray phase- . . .

7. I. Zanette, T. Weitkamp, T. Donath, S. Rutishauser, and C. David, Phys. Rev. Lett.105, 248102 (2010).

Primary author(s) : Ms. ZHOU, Tunhe (Biomedical and X-ray Physics, KTH Royal Instituteof Technology, Stockholm, Sweden)

Co-author(s) : Dr. ZANETTE, Irene (Diamond Light Source, Harwell Science and InnovationCampus, Didcot, OX11 0DE, United Kingdom); Ms. ZDORA, Marie-christine (DiamondLight Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE, United Kingdom;Department of Physics & Astronomy, University College London, London WC1E 6BT, UnitedKingdom; Department of Physics & Astronomy, University of Southampton, SouthamptonSO17 1BJ, UK); Dr. THIBAULT, Pierre (Department of Physics & Astronomy, University ofSouthampton, Southampton SO17 1BJ, UK); Dr. LUNDSTRÖM, Ulf (Biomedical and X-rayPhysics, KTH Royal Institute of Technology, Stockholm, Sweden); Dr. LARSSON, Daniel H.(Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 SandHill Road, Menlo Park, CA 94025, USA); Prof. HERTZ, Hans M. (Biomedical and X-ray Physics,KTH Royal Institute of Technology, Stockholm, Sweden); Prof. PFEIFFER, Franz (Institut fürDiagnostische & Interventionelle Radiologie, Technische Universität München, 81675 München,Germany); Dr. BURVALL, Anna (Biomedical and X-ray Physics, KTH Royal Institute ofTechnology, Stockholm, Sweden)

Presenter(s) : Ms. ZHOU, Tunhe (Biomedical and X-ray Physics, KTH Royal Institute ofTechnology, Stockholm, Sweden)

Status: SUBMITTED

Submitted by ZHOU, Tunhe on Saturday 07 May 2016

June 12, 2016 Page 31

Imaging 2016 / Report of Abstracts A novel radiation imaging syst� . . .

Abstract ID : 25

A novel radiation imaging system with scintillatingglass gas electron multiplier and flat-panel

photodiode array

ContentIn this research we report on the recent development about a new imaging system whichis composed of a scintillating Glass Gas Electron Multiplier (G-GEM) coupled with aphotodiode sensor array based on LCD technology.Gas Electron Multiplier (GEM) is a widely used micro-pattern gaseous detector[1]. Ithas a large-area imaging capability with high position resolution because of its numerousmicroholes. Its high degree of freedom about the detector design is also attractive fordeveloping an imaging device; since it only multiplies electrons, it can be combined with avariety of readout systems.We have been developing a new GEM, G-GEM, which is composed of a photosensitive etchableglass substrate with numerous of high-aspect ratio holes fabricated with photolithographytechnique[2]. Since the G-GEM is made of glass substrate, it has overcome the problem ofoutgassing which degrades the purity of gas, and therefore it can be used as a gas sealed-typeimaging detector by removing the high pressure gas cylinder. In addition, the G-GEMhas the sufficiently thick glass substrate to support itself over the entire sensitive area.This self-support capability and hence the mechanical stability is necessary for achieving arobust and practical imaging device. The photolithography technique is relatively low-costproduction technique even with a large-area substrate. We have already experimentallydemonstrated the operation of large-area type G-GEM, which has a sensitive area of 280 mmsquare[3]. The size is almost comparable to those of the flat panel detectors and imagingplates.We have been investigating the imaging capability of G-GEM for these years, aiming forachieving a practical flat-panel like imaging detector with G-GEM. Because G-GEM is agaseous detector, it can visualize many different kinds of radiation such as neutron, heavycharged particles, protons, by using appropriate gas and converters. This is going to be abig advantage compared with solid state detector based imaging devices.For the two dimensional readout system of G-GEM, the optical readout system is verypromising. G-GEM has high gain property (more than 104 with single stage) and thusproduces a number of scintillating photons at the same time with its electron avalancheprocess, if it is operated under noble gas and CF4 gas mixture. The wavelength of scintillatingphotons from G-GEM is in visible region and is thus compatible with many kinds ofphotosensors.Recently we fabricated a 100 mm square photodiode array based on LCD technology. Eachphotodiode pixel is about 200 µm square. Coupling the G-GEM with this photodiode array,we suggest a new flat-panel like imaging system. In this system, A thin glass plate which hasa single-sided ITO coating was placed on the photodiode array panel with the ITO side up.The G-GEM was then placed on the glass plate. The glass was used to electrically separatethe G-GEM from the photodiode array, and its ITO coating was to prevent charge-up ofavalanche electrons. The bottom-side of G-GEM was connected to the ground and thetop-side was biased at negative high voltage with a high voltage supply. We flushed thesystem with a scintillation gas (Ar/CF4 90/10 or Ne/CF4 90/10) in the gas flow mode. Thescintillating photons from avalanche went through the glass plate and reached the pixelsof photodiode array. We will show the results of imaging with low energy X-rays and lowatomic number samples.References

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Imaging 2016 / Report of Abstracts A novel radiation imaging syst� . . .

[1]F. Sauli, Nucl. Instr. and Meth. Phys. Res. A 386 (1997) 531[2]H. Takahashi, Y. Mitsuya, T. Fujiwara, et al., Nucl. Instr. and Meth. Phys. Res. A 724(2013) 1[3]Y. Mitsuya, T. Fujiwara, T. Fushie, T. Maekawa, H. Takahashi, Nucl. Inst. and Meth.Phys. Res. A 795 (2015) 156

Primary author(s) : MITSUYA, Yuki (The University of Tokyo)

Co-author(s) : Dr. FUJIWARA, Takeshi (AIST); Mr. MIYOSHI, Hiroaki (SHARPCorporation); Prof. TAKAHASHI, Hiroyuki (The University of Tokyo); Prof. UESAKA,Mitsuru (The University of Tokyo)

Presenter(s) : MITSUYA, Yuki (The University of Tokyo)

Status: SUBMITTED

Submitted by MITSUYA, Yuki on Sunday 08 May 2016

June 12, 2016 Page 33

Imaging 2016 / Report of Abstracts Point-focusing stack lens for . . .

Abstract ID : 26

Point-focusing stack lens for high-energy x-ray

Content

For high-energy x rays, planar prism-array lenses have been in successful use for line focusing.Meanwhile point focusing is achieved by two planer lens in an orthogonal configuration.However this setup will double the lens length, increase the attenuating material and limitthe aperture size. In the Royal Institute of Technology (KTH), the development of true point-focusing x-ray lenses made of SU-8 is under way, which are cylindrically symmetric versionsof the planar prism-array lenses. The lenses are built up by stacking a plurality of SU-8discs, each disc having some circular prisms and manufactured by focused UV lithography.In this paper, the fabrication processes of the lenses are released and simulation modelsare developed to evaluate the performance of the described lenses. And the experimentalevaluation will be done with x-ray tube and synchrotron radiation soon.

Primary author(s) : Mr. MI, Wujun (The Royal Institute of Technology)

Co-author(s) : Prof. DANIELSSON, Mats (KTH)

Presenter(s) : Mr. MI, Wujun (The Royal Institute of Technology)

Status: SUBMITTED

Submitted by MI, Wujun on Sunday 08 May 2016

June 12, 2016 Page 34

Imaging 2016 / Report of Abstracts CT lung volume histogram cor� . . .

Abstract ID : 27

CT lung volume histogram correction based on amulti-scanner phantom study

ContentComputed Tomography is widely used in assessing lung density based on CT attenuationmeasured in Hounsfield Units (HU). The lung density metrics are quantities derived fromCT number histograms that are generated from lung CT images. This work attempts torelate the result in density calibration using a phantom containing discrete uniform densityreference standards to the histogram of the real lung density with a continuing varyingdistribution.Two most common lung density metrics are: a) the percentage of voxels with CT numbersbelow a threshold, e.g. if RA-950 = 0.04, then 4% of the volume is below the threshold valueof -950 HU, and b) a single CT number marking a given fraction of the lung volume, e.g. ifPerc15 = -915 HU, then -915 HU marks the lower density region that takes up 15% of thetotal lung volume. These metrics are being pursued as quantitative image biomarkers forthe diagnosis and monitoring of lung density changes due to emphysema related to chronicobstructive pulmonary disease (COPD) [1]. However, the utility of both types of densitymetrics has been limited by poor reproducibility dominated by within-subject variation dueto varying state of lung inflation, and is being addressed by applying volume adjustmentbased on physical or statistical models in patient studies [2]. In addition to quantifying theeffect of volume adjustment, it is necessary to assess other sources of variation contributingto a given lung density CT measure in a clinical setting. This is achieved by conductingphantom studies in a variety of scanner models to assess the variations attributed to scannercalibration and measurement uncertainty free from biological noise [3]. Based on the resultsof the phantom study where the maximum variation encountered in the group of scannersemployed, we assess the influence of the scanner variation on the outcome of the lung densitymetrics by examining how much a given shift in the lung volume histogram changes the lungdensity metrics.A sample lung volume histogram was generated by segmenting the CT images within therange of -1000 HU to -525 HU over the entire lung region, depicting the number of pixels fora given HU value for the entire density range. The density metrics were determined fromthis histogram. The previous vendor study used a phantom with three reference standardsto calibrate each scanner in the lung density region for a total of 22 scanner-protocolcombinations. The internal calibration with air and water was first applied to the CTnumber of the targeted density, and then the calibration for each scanner and protocolwas made. A correction factor was determined based on a single-parameter model thatassumes a parametric energy dependence applying to all low Z elements and mixtures [4].The maximum range of the correction factor thus determined is used in this work to shift thehorizontal axis of the histogram, assuming a simple multiplication of every bin by the samefactor. A rescaled histogram is then reassessed for the density metrics. For the metric ofPerc15, the range of change is from -2.7 HU to +1.6 HU. These values are small compared tothe current clinically significant change in Perc15 of 11 HU [5], but are not entirely negligible.We will report the statistical analysis of all available histograms.References[1] D. A. Lynch, et al.,“CT-Definable Subtypes of Chronic Obstructive Pulmonary Disease”,Radiology, 277(1) (2015) doi: http://dx.doi.org/10.1148/radiol.2015141579[2] S. Fein et al, Meta-analysis of patient studies of lung density CT with lung volumeadjustment, unpublished

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Imaging 2016 / Report of Abstracts CT lung volume histogram cor� . . .

[3] H. Chen-Mayer et al., Standardizing CT Lung Density Measure Across Scanner Manufac-turers, unpublished[4] L. C. Martinez et al., A parametrization of the CT number of a substance and its use forstoichiometric calibration, Physica Medica 28 33–42 (2012).[5] QIBA Lung Density Profile, unpublished

Primary author(s) : Dr. CHEN-MAYER, H. Heather (NIST)

Co-author(s) : Dr. JUDY, Philip (Brigham and Women’s Hospital); Dr. FAIN, Sean(University of Wisconsin)

Presenter(s) : Dr. CHEN-MAYER, H. Heather (NIST)

Comments:Due to schedule restrictions I may not able to attend the first day of the conference;but I expect to make it to day 2. Sorry for the inconvenience. Thank you. H. HeatherChen-Mayer

Status: SUBMITTED

Submitted by CHEN-MAYER, Heather on Sunday 08 May 2016

June 12, 2016 Page 36

Imaging 2016 / Report of Abstracts New universal cross sections for . . .

Abstract ID : 28

New universal cross sections for electromagneticinteractions in image-guided hadrontherapy

ContentRadiotherapy by fast multiply charged nuclei (protons, alpha particles, carbon ions, etc.)is used in medicine for treatment of patients with deep-seated tumours. This treatmentmodality has been suggested by physicist Robert Wilson in 1946 [1]. His proposal wasbased on the Bragg-peak feature [2] of heavy charged particles that deposit most of theirenergy at the tumour site and, thus, spare healthy tissue. This enables better tumor control,the ultimate goal of radiology. As such, ions were immediately appreciated and promptlyused by physicians. The Bragg-peak property of atomic nuclei is due to their large masses(relative to electrons) causing minimal multiple scatterings and struggling with merely slightdeflections (a fraction of mrad) from the initial path dictated by the energy at the beamentrance to the body. In image-guided hadrontherapy, deposited doses are monitored by aPET-CT camera (positron emission tomography – computerized tomography) inserted intothe beamline, as done in hospital-based accelerators. This device locates positron-electronannihilation events stemming from transmutation of nuclei from the target and/or positron-emitting projectiles (secondary particles, e.g. isotopes 13C from fragmented primaries 14Cfor impact of carbon ions). Any PET-CT-detected deviation from a dose-planning systemwould necessitate a prompt correction of the algorithms for predicting dose depositions, sothat the subsequent dose delivery in fractionated hadrontherapy could better conform to thetarget (tumour). The predictions of energy losses of ions during their passage through thetissue must account for nuclear reactions (mainly neutron emissions) and electro-magneticinteractions (via atomic collisions: ionization, charge transfer, neutralization). Data basesfor nuclear reactions are reasonably reliable and up-do-date. However, cross sections foratomic processes used in algorithms for hadrontherapy still employ the Bethe-Bloch formula(based solely on ionization losses) from 1930 [3] and 1933 [4], which is inapplicable at impactenergies below 1 MeV/amu. Such a high energy cut-off excludes doses imparted to thetissue by charge exchange (electron capture from the target by projectiles) which is themost important atomic process near the Bragg peak. In the vicinity of the Bragg peak,projectiles slow down to such an extent that charge exchange dominates over ionization[5-8]. To bridge this gap, we present new, simple analytical cross-section expressions foratomic and molecular targets involved in charge exchange and ionization. These formulae(to be presented at the Conference) are universally valid from low through intermediate tohigh impact energies. They have successfully been tested on abundant experimental datafrom the literature for electron capture and ionization including both atomic and moleculartargets. The rationale of this research is twofold: (1) to use the present cross sections withinthe protocols for dose planning systems in hadrontherapy as the improved predictions ofenergy losses from electromagnetic interactions, and (2) to provide the precomputed accuratedatabases for Monte Carlo simulations that, alternatively, can perform fast sampling fromthe present user-friendly distributions.

1. RR Wilson, Radiology 47 (1946) 487-91

2. WH Bragg, Phil Mag 8 (1904) 715-25

3. H Bethe, Ann Phys Lpz 5 (1930) 325-400

4. F Bloch, Ann Phys Lpz 16 (1933) 285-320

5. Dz Belkic, I Mancev, J Hanssen, Rev Mod Phys, 80 (2008) 249-314 (Review)

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Imaging 2016 / Report of Abstracts New universal cross sections for . . .

6. Dz Belkic, J Math Chem 47 (2010) 1366-1419 (Review)

7. Dz Belkic, Quantum theory of high-energy ion-atom collisions, Taylor and Francis,London, 2010

8. Dz Belkic (Editor), Fast ion-atom and ion-molecule collisions, World Scientific, Singa-pore, 2013

Primary author(s) : Prof. BELKIC, Dzevad (Karolinska Institutet)

Presenter(s) : Prof. BELKIC, Dzevad (Karolinska Institutet)

Status: SUBMITTED

Submitted by BELKIC, Karen on Sunday 08 May 2016

June 12, 2016 Page 38

Imaging 2016 / Report of Abstracts Optimization of magnetic reso� . . .

Abstract ID : 29

Optimization of magnetic resonance spectroscopicimaging for noisy data from cancerous ovary

ContentThe ovary is a small, moving ellipsoid organ. Its normal mean volume in adult females rangesfrom 6.1 cm3 to 1.8 cm3 depending on age. Especially in early-stage cancer, the ovary may beonly slightly enlarged or of normal size [1]. Morphologic imaging techniques are insufficientlyspecific for diagnosing ovarian cancer (many false positives) and are not recommended forovarian cancer screening in the general population [2]. Ovarian cancer remains a major causeof cancer deaths among women worldwide, due mainly to late detection, whereas early-stageovarian cancer has an excellent prognosis.Magnetic resonance spectroscopic imaging (MRSI) would be an ideal candidate for early ovarian cancer detection, being non-invasive, free of ionizing radiation \& going beyond anatomic imaging to identify the metabolic features of cancer. However, reliance on the fast Fourier transform (FFT) for analysis of MRSI time signals has severely limited the diagnostic yield of MRSI for ovarian cancer, since the FFT is a low resolution, non-parametric processor which at short total signal lengths gives only rough total shape spectra [3].

By contrast, the fast Pade transform (FPT), an advanced signal processor with high-resolution and parametric (quantification-equipped) features, is particularly amenable to processing MRSI time signals from the ovary [3]. In the FPT, the spectrum is given by a non-linear response function as the unique ratio of 2 polynomials. The high resolution of the FPT is due to extrapolation \& interpolation capabilities \& nonlinearity, that contribute to noise suppression. The FPT has two variants: the FPT(+) and FPT(-) that converge, respectively, inside \& outside the unit circle. The FPT(-) is an accelerator of convergence [4], while the FPT(+) converts divergent series into convergent ones via the Cauchy analytical continuation [5].

Both FPT variants are herein applied to MRSI encodings from cancerous ovarian cyst fluid [6] with detailed analysis of noisy data. All the genuine resonances were clearly identified by both FPT variants, with the correct metabolite concentrations, at short total signal lengths. Signal-noise separation was most efficient in the FPT(+) where the genuine \& spurious resonances are segregated inside \& outside the unit circle, respectively. In the FPT(-), both these resonance types are mixed and all lie outside the unit circle. Pole-zero coincidence of spurious resonances remained complete in the FPT(+), with a denoised spectrum produced automatically. Non-physical resonances were identified in the FPT(-) by their instability at different total signal lengths. The two FPT variants provide self-contained cross-validation of the reconstructed spectral parameters, from which the metabolite concentrations of cancerous ovary are reliably computed. Pade-optimized MRSI thus holds promise for improved ovarian cancer diagnostics.

1. J Seidman, B Wang, Gyn Oncol 106 (2007) 201-6

2. V Moyer, Ann Intern Med 157 (2012) 900-4

3. K Belkic, Nucl Instrum Meth Phys Res A 580 (2007) 874-80

4. Dz Belkic, Nucl Instrum Methods Phys Res A 525 (2004) 366-71

5. Dz Belkic, Nucl Instrum Methods Phys Res A 525 (2004) 372-8

6. E Boss, et al, High-resolution proton nuclear magnetic resonance spectroscopy ofovarian cyst fluid. NMR Biomed 13 (2000) 297-305

Support: Marsha Rivkin Center for Ovarian Cancer Research & King Gustav 5th JubileeFund

Primary author(s) : Prof. BELKIC, Karen (Karolinska Institutet)

Presenter(s) : Prof. BELKIC, Karen (Karolinska Institutet)

Status: SUBMITTED

Submitted by BELKIC, Karen on Sunday 08 May 2016

June 12, 2016 Page 39

Imaging 2016 / Report of Abstracts High resolution imaging using . . .

Abstract ID : 32

High resolution imaging using structuredscintillators and photon counting

ContentStructured scintillators, in which the scintillating material performs as both x-ray absorptionmedia and waveguide for secondary emitted photons, are conventionally used for imagingpurposes [1]. In this work, the structure of interest is made by making high aspect ratiopores on silicon using microfabrication techniques and consecutive oxidation of the porewalls. Then, the pores are filled with CsI (Tl) as the scintillating material and due to thehigher refractive index of silicon oxide compared to CsI, the pores perform as wave guidesfor secondary visible photons [2]. In our recent research, we have demonstrated that a veryhigh imaging resolution (MTF ≥ 10%, at below 100 cy/mm, using the slanted edge method)can be achieved by reducing the periodicity of the pores (4 um pitch) [3, 4]. However,fabrication of a thick enough scintillator with an extremely fine structure, which is capable ofconverting enough x-ray quanta to generate a high enough signal to noise ratio, is extremelycomplicated. To address this issue, we investigated a photon counting approach using thementioned structured scintillators. In this approach we integrated an image intensifier intoour imaging setup, which was already composed of a custom made microscope and a liquidNitrogen cooled CCD, in order to be able to detect single X-ray impact events. Then, bypost processing of successive, shortly exposed, images with random distributions of singleevents, one may build up high resolution images at a minimum X-ray dose. In this work, wediscuss the setup conditions, the processing method and the generated images in order toinvestigate the prospects and performance of this approach using our structured scintillators.References:

1. V.V. Nagarkar, T.K. Gupta, S.R. Miller, Y. Klugerman, M.R. Squillante, and G.Entine “Structured CsI(Tl) Scintillators for X-ray Imaging Applications,” IEEE Trans.Nucl. Sci., 45, 492-496 (1998).

2. P. Kleimann, J. Linnros, C. Fröjdh, C.S. Petersson “An X-ray imaging pixel detectorbased on a scintillating guides screen,” IEEE Trans. Nucl. Sci., 47, 1483-1486 (2000).

3. Y. Hormozan, S. Hu Yun, O. Svenonius, and J. Linnros “Towards High-ResolutionX-Ray Imaging Using a Structured Scintillator,” IEEE Trans. Nucl. Sci., 59, 19-23(2012).

4. Y. Hormozan, I. Sychugov, and J. Linnros “High-resolution x-ray imaging using astructured scintillator,” J. Med. Phys., 43, 609 (2016)

Primary author(s) : Mr. HORMOZAN, Yashar (Ph.D. student, Materials and Nano PhysicsDepartment, KTH – Royal Institute of Technology, Kista, Stockholm, 16440, Sweden)

Co-author(s) : Dr. SYCHUGOV, Ilya (Lecturer, Materials and Nano Physics Department,KTH – Royal Institute of Technology, Kista, Stockholm, 16440, Sweden); Prof. LINNROS, Jan(Professor, Materials and Nano Physics Department, KTH – Royal Institute of Technology, Kista,Stockholm, 16440, Sweden)

Presenter(s) : Mr. HORMOZAN, Yashar (Ph.D. student, Materials and Nano PhysicsDepartment, KTH – Royal Institute of Technology, Kista, Stockholm, 16440, Sweden)

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Imaging 2016 / Report of Abstracts High resolution imaging using . . .

Status: SUBMITTED

Submitted by Mr. HORMOZAN, Yashar on Monday 09 May 2016

June 12, 2016 Page 41

Imaging 2016 / Report of Abstracts Imaging x-rays and gamma-rays . . .

Abstract ID : 33

Imaging x-rays and gamma-rays using stacked metalmesh dynodes and MCP

Content

We present Monte Carlo and beam test results on using thick stacks of fine mesh dynodes,micro machined metal dynodes, and some forms of glass MCP as the medium to: a)convert penetrating radiation into secondary-emission(SE) electrons, b) amplify the resultingelectrons into detectable signals, and c) detect the resulting image, using multipixel orcross-delay line anodes. The imaging resolution can be sub-mm, and the energy resolutioncan be ˜1% at 1 MeV depending on the SE mediums. The dynode meshes considered areW or Ta meshes fabricated from 5 micron wires. Other metals have interesting properties,such as neutron sensitivity using B and Be based claddings or materials, and materials withlarger radiation lengths. If the meshes are coated with synthetic diamond, the secondaryyield per stage can be ˜100 per mesh. The meshes can be packed so that the density of theresulting detector can be 30% of the base mesh material. Beam tests using mesh PMT arepresented.The virtues are high speed, low cost, exceptional radiation resistance (similar toSE beam monitors at accelerators) and rugged. Unlike PMT photocathode fabrication, thedynodes alone can be taken up to air, can be baked out at refractory temperatures, andrequire a vacuum 1000x worse than a PMT photocathode.

Primary author(s) : Prof. WINN, David (Fairfield University, Fairfield, CT 06824 USA)

Co-author(s) : Prof. ONEL, Yasar (U.Iowa); Dr. BILKI, Burak (U.Iowa); Dr. WETZEL,James (U.Iowa)

Presenter(s) : Prof. WINN, David (Fairfield University, Fairfield, CT 06824 USA)

Status: SUBMITTED

Submitted by WINN, David on Monday 09 May 2016

June 12, 2016 Page 42

Imaging 2016 / Report of Abstracts The DESIREE facility: imaging . . .

Abstract ID : 34

The DESIREE facility: imaging particles in anextreme environment.

ContentWe have constructed an electrostatic ion storage ring for operation at cryogenic temperatures[1, 2]. This device allows ion beams of opposite charge to be confined under extreme highvacuum (residual gas density p=2x104 cm−2) and cryogenic (13 K) conditions in separate“rings” and then merged over a common straight section. The unique construction of thisDouble ElectroStatic Ion Ring ExpEriment (DESIREE) apparatus allows for studies ofinteractions between cations and anions at low and well-defined centre-of-mass energies downto 10 meV energies. DESIREE is now completing its commissioning stages.Any given experiment can be undertaken in either of the two rings or a single experimentcan utilise both rings and, in most cases, the aim is to measure critical parameters such asenergy-dependent reaction cross sections or product branching fractions. One of the mostunique aspects of the way DESIREE has been planned and constructed is the merging regionin which both rings are used to store ions: cations in one and anions in the other.One of the simplest reactions to make use of this aspect is mutual neutralisation (MN). Thesimplest mutual neutralisation reaction is H− + H+ →H∗

2→H∗ + H. To investigate thisreaction in DESIREE requires a multi-hit microchannel-plate detector with its capability ofdetermining arrival times and positions of the neutral products created in the same collisionevent, in this case the two hydrogen atoms. Detailed analysis of these data will allow thekinetic energy released in each MN event to be determined, giving exact identification of theelectronic state of the product H atoms.In this presentation, I will discuss the testing and integration of just such detectors and theproblems associated with their operation in UHV and ultra-cold cryogenic conditions [3].[1] R. D. Thomas et al. Rev. Sci. Instrum. 82, 065112 (2011). [2] H. T. Schmidt et al. Rev.Sci. Instrum. 83, 055115 (2013). [3] S. Rosén et al. Rev. Sci. Instrum. 78, 113301 (2007).

Primary author(s) : Dr. THOMAS, Richard (Stockholm University); Prof. CEDERQUIST,Henrik (Stockholm University); Prof. SCHMIDT, Henning (Stockholm University); Dr. ROSÉN,Stefan (Stockholm University); Ms. ANDERSON, Emma (Stockholm University)

Presenter(s) : Dr. THOMAS, Richard (Stockholm University)

Status: SUBMITTED

Submitted by THOMAS, Richard on Wednesday 01 June 2016

June 12, 2016 Page 43

Imaging 2016 / Report of Abstracts How to get a Nobel Prize

Abstract ID : 35

How to get a Nobel Prize

ContentA bit about the origins and history of the Nobel Prize in Physics.The Nobel Prizes for science and its applications, are considered by many to be the mostprestegious. How did it happen that Sweden was able to build this stature around theprizes? This talk will address that question with a brief look at the history of how prize wasfounded, and a description of the process that has evolved for choosing the winners. Thetalk will focus on prizes in physics, and in particular those relating to imaging.

Primary author(s) : Prof. HAVILAND, David (Nanostructure Physics, KTH Royal Instituteof Technology)

Presenter(s) : Prof. HAVILAND, David (Nanostructure Physics, KTH Royal Institute ofTechnology)

Status: SUBMITTED

Submitted by NYSTRÖM, Sofia on Sunday 12 June 2016

June 12, 2016 Page 44