Unit:
Κατεύθυνση Ιατρική Φυσική-ΑκτινοφυσικήLibrary of the School of Health Sciences
Author:
Zarketan Despoina
Supervisors info:
Ε. Στυλιάρης, Αναπληρωτής Καθηγητής, Τμήμα Φυσικής, ΕΚΠΑ
Π. Καραΐσκος, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Κ. Λουκάς, Επίκουρος Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Original Title:
Resolution Study of a γ-Camera System for Single Photon Emission Computed Tomography (SPECT) at Preclinical Level
Translated title:
Resolution Study of a γ-Camera System for Single Photon Emission Computed Tomography (SPECT) at Preclinical Level
Summary:
The current thesis is an experimental study which focuses on the resolution determination of a small-field γ-Camera system dedicated to Single Photon Emission Computed Tomography (SPECT) at preclinical level. The Position Sensitive Photomultiplier Tube (PSPMT) was characterized in terms of its spatial and energy resolution. For this purpose, light pulses of controlled time-width were guided to the front surface of the PSPMT and the multi-anodic charge signal was detected and analyzed. The linearity of the accumulated charge as a function of the light pulse duration, which equivalently reflects the energy of an incident γ-ray photon, was verified. In parallel, the overall charge gain of the PSPMT system was measured for various values of the high voltage power supply.
Simple geometrical phantoms consisted of 99mTc filled capillaries were used to evaluate the performance and the spatial resolution of the whole γ-Camera system. Detected aberrations in planar imaging were eliminated by applying 1D and 2D linear interpolation functions based on supporting points with known nominal position. Corrected images on planar and tomographic level were produced for a more complicated geometrical phantom as well as for specific targeted organs of a small mouse injected with 99mTc radiopharmaceutical.
Main subject category:
Health Sciences
Keywords:
Position Sensitive PhotoMultiplier Tube (PSPMT), Small-field γ-Camera, Spatial resolution, Energy response, Gain factor, Correction algorithm, Algebraic Reconstruction Technique (ART)
