Warsaw Medical Physics Meeting 2015

14-05-2015 09:00 to 16-05-2015 16:00

Center of New Technologies
Warsaw, Poland

Texture analysis of CT perfusion in head and neck cancer patients

  • 15-05-2015 11:30

The response to radiotherapy depends on the tumor physiology. The aim of this project was to compare second order statistical texture parameters in CT perfusion of head and neck patients with respect to tumor site, stage and human papillomavirus (HPV) status. Energy, entropy, contrast and correlation were calculated using Python. Median values, as the standard first order parameter, were calculated for comparison. Data for 42 patients was analyzed (n=17 oropharynx, n=7 hypopharynx, n=9 larynx, n...

Comparative studies of FE boards for use of J-PET scanner

  • 15-05-2015 11:55

The Jagiellonian Positron Emission Tomograph (J-PET) prototype based on plastic scintillators is currently under development at the Jagiellonian University (see e.g. [1,2]). Each J-PET module consists of long polymer scintillator strip with fast photomultipliers connected to each end. Due to very good timing properties of each module, a new kind of front end board is needed to not diminish spacial resolution of the scanner. Three different approaches to probe signal shapes will be presented: mul...

Optimization of Levels of Voltage Thresholds in a Novel J-PET Device

  • 15-05-2015 12:40

Nowadays, in Positron Emission Tomography (PET) systems, a Time of Flight (TOF) information is used to improve the image reconstruction process. A novel concept, called J-PET scanner, offers an improvement of TOF resolution due to the use of fast plastic scintillators and dedicated electronics allowing for sampling the signals in the voltage domain [1,2,3]. Owing to Compress Sensing theory, the full waveforms of the signals are recovered [4]. In the presentation we will demonstrate that with fu...

Novel J-PET plastic scintillator with 2-(4-styrylphenyl)benzoxazole as a wavelength shifter

  • 15-05-2015 13:05

Plastic scintillators are the key part of positron emission tomography device which is being constructed at the Jagiellonian University. Experiments confirmed that low detection efficiency and slight probability of photoelectric effect do not prevent the use of plastic scintillators as detectors for 511 keV gamma quanta [1]. The novelty of the J-PET scintillator concept lies in the application of 2-(4-styrylphenyl)benzoxazole as a wavelength shifter [2]. Properties of the J-PET scintillators wi...

Application of the 4D Flow visualisation in cardiology.

  • 15-05-2015 14:15

The 4D Flow technique is a MRI method of imaging blood flow in three dimensions and time over an averaged heart cycle. It provides information about three directions of blood’s velocity. The method allows for qualitative assessment of the flow of blood through the whole imaged region. 4D Flow data gives the possibility of creating three-dimensional visualisations of the blood flow, e.g. streamlines and pathlines. Even though the method still faces some challenges (such as long acquisition times ...

Characterization of the spatial resolution of the J-PET detector

  • 16-05-2015 10:25

A prototype of the positron emission tomography device based on plastic scintillators is currently being developed at the Jagiellonian University [1-3]. Point Spread Function (PSF) determined for the detector with different scintillator shapes will be shown. PSF can be used both to determine and to improve spatial resolution in PET scanners [4]. Spatial resolution of the J-PET prototype was determined using two 22Na radioactive isotopes placed inside the detector. [1] P. Moskal, S. Niedźwick...

Performance of the 24-module prototype of the J-PET detector

  • 16-05-2015 11:10

A prototype of Positron Emission Tomography scanner is being developed by the J-PET collaboration at the Jagiellonian University [1,2,3,4]. The J-PET detector is built out of plastic scintillators characterized by good timing properties. The reconstruction of the hit-position of gamma quanta is based predominantly on the measurement of the time of registered signals. In order to reconstruct proper hit-position of the gamma quanta the time synchronization of many detector modules is needed. Meth...

Performance characteristics of J-PET detector simulated using GATE package

  • 16-05-2015 13:00

Novel PET system based on plastic scintillators is developed by the J-PET collaboration [1,2]. In order to determine performance characteristics of built scanner prototype, advanced computer simulations must be performed. Simulations are performed using GATE software (Geant4 Application for Tomographic Emission) in CIŚ cluster (Świerk Computing Centre at National Centre for Nuclear Research). Performance of any PET scanner may be evaluated inter alia using dependencies between true, scattered...