Unit:
Κατεύθυνση Πυρηνική Φυσική και Φυσική Στοιχειωδών Σωματιδίων (ΒΑΣΙΚΗ ΦΥΣΙΚΗ)Library of the School of Science
Author:
Lytrosyngounis Ioannis
Supervisors info:
Στυλιάρης Ευστάθιος, Αναπληρωτής Καθηγητής, Τμήμα Φυσικής, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
Original Title:
Μελέτη των Ορίων Ανιχνευσιμότητας Καρκινικών Όγκων στη Μονοφωτονική Τομοσπινθηρογραφία με Εξειδικευμένο Ομοίωμα Μαστού
Translated title:
Cancer Lesions Detectability Limits in the Single Photon Emission Computed Tomography (SPECT) with a Dedicated Breast Phantom
Summary:
Breast imaging for early stage cancer diagnosis is still mainly relying on planar imaging techniques. Due to spatial resolution and sensitivity limitations in combination with absorption effects, clinical scanners show a poor performance in three-dimensional tomographic imaging. In order to exercise in detail the detectability limits of small breast cancer lesions in a highly noisy background, a SPECT study with a dedicated breast phantom is presented in this thesis. The small field and high efficiency γ-Camera system equipped with a Position Sensitive PhotoMultiplier Tube (PSPMT) of our SPECT laboratory was utilized for this study. The position information was reconstructed with Anger technique, while the hot spot activity-to-background ratio in the breast phantom was examined using 99mTc water solution. Various observed planar images have been extensively analyzed for this ratio ranged from 5:1 to 1:1, and the obtained experimental values were in a good agreement with simulations that performed in detail by means of GEANT4/GATE Monte-Carlo techniques, both on planar and tomographic level. A detailed specification of the tomographic limits by this method could potentially define the clinical value for the tomographic images of various small-volume and specific activity concentrations in a controllable Signal-to-Noise environment.
Main subject category:
Science
Keywords:
γ-Camera, Single Photon Emission Computed Tomography (SPECT), Breast Phantom, Monte-Carlo, GEANT4/GATE
