title: Simulation study comparing high-purity germanium and cadmium zinc telluride detectors for breast imaging.
abstract: We conducted simulations to compare the potential imaging performance for breast cancer detection with High-Purity Germanium (HPGe) and Cadmium Zinc Telluride (CZT) systems with 1% and 3.8% energy resolution at 140 keV, respectively. Using the Monte Carlo N-Particle (MCNP5) simulation package, we modelled both 5 mm-thick CZT and 10 mm-thick HPGe detectors with the same parallel-hole collimator for the imaging of a breast/torso phantom. Simulated energy spectra were generated, and planar images were created for various energy windows around the 140 keV photopeak. Relative sensitivity and scatter and the torso fractions were calculated along with tumour contrast and signal-to-noise ratios (SNR). Simulations showed that utilizing a ±1.25% energy window with an HPGe system better suppressed torso background and small-angle scattered photons than a comparable CZT system using a -5%/+10% energy window. Both systems provided statistically similar contrast and SNR, with HPGe providing higher relative sensitivity. Lowering the counts of HPGe images to match CZT count density still yielded equivalent contrast between HPGe and CZT. Thus, an HPGe system may provide equivalent breast imaging capability at lower injected radioactivity levels when acquiring for equal imaging time.
authors.affiliation: Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA. Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA.
authors.forename: D L
authors.initials: DL
authors.lastname: Campbell
authors.forename: T E
authors.initials: TE
authors.lastname: Peterson
mesh_terms: D001940:Breast / Q000000981:diagnostic imaging*; D002104:Cadmium / Q000737:chemistry*; D003198:Computer Simulation; D005260:Female; D005857:Germanium / Q000737:chemistry*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D017785:Photons; D049268:Positron-Emission Tomography / Q000295:instrumentation / Q000379:methods; D011877:Radionuclide Imaging / Q000295:instrumentation*; D059629:Signal-To-Noise Ratio; D013691:Tellurium / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: C474490:CdZnTe; D005857:Germanium; D002104:Cadmium; D015032:Zinc; D013691:Tellurium