Effects of Fe as a physical filter on spectra of Technitium-99m, uniformity, system volume sensitivity and spatial resolution of Philip ADAC Forte dual-head gamma camera
Single photon emission computed tomography (SPECT) imaging inherits some limitations, i.e., due to scattered gamma photons which degrade spatial resolution causes poor image quality. This study attempts to reduce a fraction of scattered gamma photons before reaching gamma camera detector by using Fe...
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| Format: | Article |
| Language: | English English |
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Institute of Physics Publishing (UK)
2014
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| Online Access: | http://irep.iium.edu.my/39997/ http://irep.iium.edu.my/39997/1/Effect_of_Fe_as_a_physical_filter....pdf http://irep.iium.edu.my/39997/3/39997_Effects%20of%20Fe%20as%20a%20physical%20filter%20on%20spectra_SCOPUS.pdf |
| _version_ | 1848781881065078784 |
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| author | Sohaimi, Norhanna Abdullah, Nazifah Shah, Sayed Inayatullah Zakaria, Ahmad |
| author_facet | Sohaimi, Norhanna Abdullah, Nazifah Shah, Sayed Inayatullah Zakaria, Ahmad |
| author_sort | Sohaimi, Norhanna |
| building | IIUM Repository |
| collection | Online Access |
| description | Single photon emission computed tomography (SPECT) imaging inherits some limitations, i.e., due to scattered gamma photons which degrade spatial resolution causes poor image quality. This study attempts to reduce a fraction of scattered gamma photons before reaching gamma camera detector by using Fe sheet (0.35 mm and 0.40 mm) as a physical filter. Also investigate the effects on spectra of Tc-99m, spatial resolution, system volume sensitivity and uniformity. The thickness of Fe physical filter is selected on the basis of percentage attenuation calculations of different gamma ray energies by various thicknesses of material. Data were acquired using Philip ADAC forte dual-head gamma camera without and with physical filter with LEHR collimator installed. For spectra, uniformity and system volume sensitivity, a cylindrical source tank filled with water added with Tc-99m was scanned. Uniformity and system volume sensitivity images were reconstructed with FBP method by applying Butterworth filter of order 5, cut-off frequency 0.35cycles/cm and Chang’s attenuation correction method using 0.13 cm-1 linear attenuation coefficient. Spatial resolution study was done by scanning a line source (0.8 mm inner diameter) of Tc-99m at various source-to-collimator distances in air and in scattering medium without and with physical filter. A substantial reduction in count rate from Compton and photopeak regions of Tc-99m spectra with physical filter is recorded. Improvement in spatial resolution with physical filter up to 4 cm source-to-collimator distance is obtained. System volume sensitivity was reduced and no improvement in uniformity. These thicknesses of physical filter may be tested further by scanning different planar/SPECT phantoms in Tc-99m imaging. |
| first_indexed | 2025-11-14T15:56:36Z |
| format | Article |
| id | iium-39997 |
| institution | International Islamic University Malaysia |
| institution_category | Local University |
| language | English English |
| last_indexed | 2025-11-14T15:56:36Z |
| publishDate | 2014 |
| publisher | Institute of Physics Publishing (UK) |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | iium-399972017-09-19T02:41:58Z http://irep.iium.edu.my/39997/ Effects of Fe as a physical filter on spectra of Technitium-99m, uniformity, system volume sensitivity and spatial resolution of Philip ADAC Forte dual-head gamma camera Sohaimi, Norhanna Abdullah, Nazifah Shah, Sayed Inayatullah Zakaria, Ahmad QC Physics Single photon emission computed tomography (SPECT) imaging inherits some limitations, i.e., due to scattered gamma photons which degrade spatial resolution causes poor image quality. This study attempts to reduce a fraction of scattered gamma photons before reaching gamma camera detector by using Fe sheet (0.35 mm and 0.40 mm) as a physical filter. Also investigate the effects on spectra of Tc-99m, spatial resolution, system volume sensitivity and uniformity. The thickness of Fe physical filter is selected on the basis of percentage attenuation calculations of different gamma ray energies by various thicknesses of material. Data were acquired using Philip ADAC forte dual-head gamma camera without and with physical filter with LEHR collimator installed. For spectra, uniformity and system volume sensitivity, a cylindrical source tank filled with water added with Tc-99m was scanned. Uniformity and system volume sensitivity images were reconstructed with FBP method by applying Butterworth filter of order 5, cut-off frequency 0.35cycles/cm and Chang’s attenuation correction method using 0.13 cm-1 linear attenuation coefficient. Spatial resolution study was done by scanning a line source (0.8 mm inner diameter) of Tc-99m at various source-to-collimator distances in air and in scattering medium without and with physical filter. A substantial reduction in count rate from Compton and photopeak regions of Tc-99m spectra with physical filter is recorded. Improvement in spatial resolution with physical filter up to 4 cm source-to-collimator distance is obtained. System volume sensitivity was reduced and no improvement in uniformity. These thicknesses of physical filter may be tested further by scanning different planar/SPECT phantoms in Tc-99m imaging. Institute of Physics Publishing (UK) 2014 Article PeerReviewed application/pdf en http://irep.iium.edu.my/39997/1/Effect_of_Fe_as_a_physical_filter....pdf application/pdf en http://irep.iium.edu.my/39997/3/39997_Effects%20of%20Fe%20as%20a%20physical%20filter%20on%20spectra_SCOPUS.pdf Sohaimi, Norhanna and Abdullah, Nazifah and Shah, Sayed Inayatullah and Zakaria, Ahmad (2014) Effects of Fe as a physical filter on spectra of Technitium-99m, uniformity, system volume sensitivity and spatial resolution of Philip ADAC Forte dual-head gamma camera. Journal of Physics: Conference Series, 546 (1). pp. 1-7. ISSN 1742-6588 (P), 1742-6596 (O) http://iopscience.iop.org/ 10.1088/1742-6596/546/1/012009 |
| spellingShingle | QC Physics Sohaimi, Norhanna Abdullah, Nazifah Shah, Sayed Inayatullah Zakaria, Ahmad Effects of Fe as a physical filter on spectra of Technitium-99m, uniformity, system volume sensitivity and spatial resolution of Philip ADAC Forte dual-head gamma camera |
| title | Effects of Fe as a physical filter on spectra of Technitium-99m, uniformity, system volume sensitivity and spatial resolution of Philip ADAC Forte dual-head gamma camera |
| title_full | Effects of Fe as a physical filter on spectra of Technitium-99m, uniformity, system volume sensitivity and spatial resolution of Philip ADAC Forte dual-head gamma camera |
| title_fullStr | Effects of Fe as a physical filter on spectra of Technitium-99m, uniformity, system volume sensitivity and spatial resolution of Philip ADAC Forte dual-head gamma camera |
| title_full_unstemmed | Effects of Fe as a physical filter on spectra of Technitium-99m, uniformity, system volume sensitivity and spatial resolution of Philip ADAC Forte dual-head gamma camera |
| title_short | Effects of Fe as a physical filter on spectra of Technitium-99m, uniformity, system volume sensitivity and spatial resolution of Philip ADAC Forte dual-head gamma camera |
| title_sort | effects of fe as a physical filter on spectra of technitium-99m, uniformity, system volume sensitivity and spatial resolution of philip adac forte dual-head gamma camera |
| topic | QC Physics |
| url | http://irep.iium.edu.my/39997/ http://irep.iium.edu.my/39997/ http://irep.iium.edu.my/39997/ http://irep.iium.edu.my/39997/1/Effect_of_Fe_as_a_physical_filter....pdf http://irep.iium.edu.my/39997/3/39997_Effects%20of%20Fe%20as%20a%20physical%20filter%20on%20spectra_SCOPUS.pdf |