Monte Carlo modelling of a NaI(Tl) scintillator detectors using  MCNP simulation code

Mouhti, L.; Elanique, A.; Messous, Y.

doi:10.26872/jmes.2017.8.12.481

Cited by 13 publications

(7 citation statements)

References 12 publications

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“…As measurements using the recommended dial number agreed with the Oak Ridge surrogate reference samples to less than 10%, the readings of the ionization chamber were considered reliable for the study carried out in this work. The scintillation detector’s measured energy resolution and detection efficiency over the energy range of 225 Ac gamma emissions (40-662 keV) agreed with other published studies and reports [28,32,33,34]. Consequently, this detector was also considered to be calibrated in efficiency and energy for 225 Ac analysis.…”

Section: Discussionsupporting

confidence: 82%

A Monte Carlo Method for Determining the Response Relationship between Two Commonly Used Detectors to Indirectly Measure Alpha Particle Radiation Activity

et al. 2019

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Using targeted ligands to deliver alpha-emitting radionuclides directly to tumor cells has become a promising therapeutic strategy. To calculate the radiation dose to patients, activities of parent and daughter radionuclides must be measured. Scintillation detectors can be used to quantify these activities; however, activities found in pre-clinical and clinical studies can exceed their optimal performance range. Therefore, a method of correcting scintillation detector measurements at higher activities was developed using Monte Carlo modeling. Because there are currently no National Institute of Standards and Technology traceable Actinium-225 (225Ac) standards available, a well-type ionization chamber was used to measure 70.3 ± 7.0, 144.3 ± 14.4, 222.0 ± 22.2, 299.7 ± 30.0, 370.0 ± 37.0, and 447.7 ± 44.7 kBq samples of 225Ac obtained from Oak Ridge National Lab. Samples were then placed in a well-type NaI(Tl) scintillation detector and spectra were obtained. Alpha particle activity for each species was calculated using gamma abundance per alpha decay. MCNP6 Monte Carlo software was used to simulate the 4π-geometry of the NaI(Tl) detector. Using the ionization chamber reading as activity input to the Monte Carlo model, spectra were obtained and compared to NaI(Tl) spectra. Successive simulations of different activities were run until a spectrum minimizing the mean percent difference between the two was identified. This was repeated for each sample activity. Ionization chamber calibration measurements showed increase in error from 3% to 10% as activities decreased, resulting from decreasing detection efficiency. Measurements of 225Ac using both detector types agreed within 7% of Oak Ridge stated activities. Simulated Monte Carlo spectra of 225Ac were successfully generated. Activities obtained from these spectra differed with ionization chamber readings up to 156% at 147.7 kBq. Simulated spectra were then adjusted to correct NaI(Tl) measurements to be within 1%. These were compared to ionization chamber readings and a response relationship was determined between the two instruments. Measurements of 225Ac and daughter activity were conducted using a NaI(Tl) scintillation detector calibrated for energy and efficiency and an ionization chamber calibrated for efficiency using a surrogate calibration reference. Corrections provided by Monte Carlo modeling improve the accuracy of activity quantification for alpha-particle emitting radiopharmaceuticals in pre-clinical and clinical studies.

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Section: Discussionsupporting

confidence: 82%

A Monte Carlo Method for Determining the Response Relationship between Two Commonly Used Detectors to Indirectly Measure Alpha Particle Radiation Activity

et al. 2019

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“…With and without the GEB card, we calculated two spectra of 60 Co isotope. Our next step was to assess the results against experimental data [ 34 ]. The data acquired from the MCNPX (with/without GEB) and the experiment are shown in Figure 3 .…”

Section: Methodsmentioning

confidence: 99%

A closer look at the efficiency calibration of LaBr3(Ce) and NaI(Tl) scintillation detectors using MCNPX for various types of nuclear investigations

ALMisned

Zakaly

Ali

et al. 2022

Heliyon

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“…In MCNPx simulations, the following structures were represented in the NaI(Tl) detectors: NaI(Tl) crystal, aluminum wall, aluminum window, MgO reflector and photomultiplier tube (PMT) glass window. The composition of the detector materials and dimensions were based in literature data and in the equipment manuals [15,16]. Elemental composition, in weight percentage (w%), and density (g.cm 3 ) of the detector structures are shown in Table 1.…”

Section: Methodsmentioning

confidence: 99%

“…Elemental composition (w%) and density (g.cm3 ) of the NaI(Tl) detector structures according to the literature[15,16].…”

mentioning

confidence: 99%

Monitoring internal contamination from OEW of an 18F-FDG production plant: WBC or head counting setup?

et al. 2019

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The production 18F-FDG for positron emission tomography (PET) has consistently increased over the past two decades. The risk of internal contamination at 18F-FDG production facilities exists. A setup for evaluation of the 18F-FDG activity incorporated into the OEW brain, called Head Counting System (HCS), was presented in previous works. In this study, the whole body counter setup (WBC) was evaluated for monitoring 18F incorporations. The Monte Carlo Virtual Software (VMC in-vivo) and the MCNPx code were used to assess the system calibration coefficient (CC). Three 18F distributions were simulated: i) uniformly distributed in soft tissue (UDST); ii) Na18F biodistribution (NAFB); and iii) 18F-FDG biodistribution (FDGB). The calibration coefficient of WBC was compared to the current head counting system CC under the same biodistribution conditions. The ICRP male reference voxelized phantoms (RCP_AM) was used in the simulations. The results showed that the WBC setup was more efficient than the head counter for all the studied 18F distributions: UDST = 1060 %, FDGB = 488 % and NAFB = 340 %. Despite this, especially for 18F-FDG, the possibility of bladder voiding before measurement can lead to considerable uncertainties when the WBC setup is used. On the other hand, bladder activity does not show great influence the calibration coefficient of the head counting system. Future work will evaluate the WBC sources of uncertainties in the measurement of 18F incorporated activity.

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Monte Carlo modelling of a NaI(Tl) scintillator detectors using MCNP simulation code

Cited by 13 publications

References 12 publications

A Monte Carlo Method for Determining the Response Relationship between Two Commonly Used Detectors to Indirectly Measure Alpha Particle Radiation Activity

A Monte Carlo Method for Determining the Response Relationship between Two Commonly Used Detectors to Indirectly Measure Alpha Particle Radiation Activity

A closer look at the efficiency calibration of LaBr3(Ce) and NaI(Tl) scintillation detectors using MCNPX for various types of nuclear investigations

Monitoring internal contamination from OEW of an 18F-FDG production plant: WBC or head counting setup?

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