The effect of gamma ray penetration on angle-dependent sensitivity for pinhole collimation in nuclear medicine

Nuclear medicine (NM) is a medical specialty that uses radionuclides (radioactive tracers) and ionising radiation for diagnostic and therapeutic (theranostic) purposes. Nuclear medicine arose and developed at the intersection of physics, chemistry and clinical medicine. The radiation emitted by radioisotopes can consist of gamma-, beta- and alpha emission, or it’s combination. Radioisotope of choice for medical purposes should have futher requirements: low radiotoxicity, suitable type of radiation, energy and half-life (several minutes to several hours and days), and also convenient detection of gamma ray radiation. The radionuclide is part of radiopharmaceutical (RP) and acts as its indicator. RP accumulates in morphological structures, becomes a carrier of coordinated information from patient to gamma camera or other equipment and reflects the dynamics of processes occurring in the examined organ. In 2021 NM celebrates its 80th anniversary. The trajectory of NM combines modern methods of radiotheranostics and applied genomic and post-genomic technologies.

Download Full-text

A new evaluation of the nuclear decay data of 223Ra

EPJ Web of Conferences ◽

10.1051/epjconf/202023923002 ◽

2020 ◽

Vol 239 ◽

pp. 23002

Author(s):

Aurelian Luca ◽

Mark A. Kellett

Keyword(s):

Nuclear Medicine ◽

Decay Scheme ◽

Gamma Ray ◽

Data Evaluation ◽

Nuclear Decay ◽

High Quality ◽

Targeted Radiotherapy ◽

Decay Data ◽

Evaluation Project ◽

Quality Measurements

Since 2013, the radionuclide 223Ra is used in nuclear medicine to prepare radiopharmaceuticals for targeted radiotherapy. 223Ra is a member of the natural radioactive series of actinium and decays by alpha-particle emission, populating the excited levels of 219Rn. According to the 2011 nuclear decay data evaluation within the Decay Data Evaluation Project (DDEP), by V.P. Chechev, the half-life of 223Ra is (11.43 ± 0.03) days. The decay scheme is not considered as fully complete, because of the disagreement between the measured and calculated probabilities of some alpha-transitions and incomplete information on several gamma-ray transitions. New high quality measurements of 223Ra nuclear decay data were performed and numerous results were published since 2012 and, consequently, an updated nuclear decay data evaluation was undertaken, according to the DDEP procedures. The main results obtained, focusing on the recommended data improvements, are presented and discussed in this paper.

Download Full-text

Gamma-Ray Protection Properties of Bismuth-Silicate Glasses against Some Diagnostic Nuclear Medicine Radioisotopes: A Comprehensive Study

Materials ◽

10.3390/ma14216668 ◽

2021 ◽

Vol 14 (21) ◽

pp. 6668

Author(s):

Ghada ALMisned ◽

Hesham M. H. Zakaly ◽

Shams A. M. Issa ◽

Antoaneta Ene ◽

Gokhan Kilic ◽

...

Keyword(s):

Nuclear Medicine ◽

Gamma Ray ◽

Effective Atomic Number ◽

Mean Free Path ◽

Mass Attenuation Coefficient ◽

Silicate Glasses ◽

Bismuth Silicate ◽

Diagnostic Nuclear Medicine ◽

Gamma Ray Attenuation ◽

Comprehensive Study

This study aimed to perform an investigation for the potential implementation of bismuth silicate glasses as novel shield equipment instead of ordinary shields in nuclear medicine facilities. Accordingly, a group of Bi2O3 reinforced silicate glass system were investigated and compared with ordinary shields in terms of their gamma-ray attenuation properties in diagnostic nuclear medicine radioisotope energies emitted from 99mTc, 111In, 67Ga, 123I, 131I, 81mKr, 201Tl, 133Xe. Mass attenuation coefficient (μm) results for glass samples were calculated comparatively with the XCOM program and MCNPX code. The gamma-ray attenuation parameters such as half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff) were obtained in the diagnostic gamma ray energy range from 75 to 336 keV. To confirm the attenuation performance of superior sample, obtained results were extensively compared with ordinary shielding materials. According to the results obtained, BISI6 glass sample with the highest Bi2O3 additive has an excellent gamma-ray protection.

Download Full-text