Repository logo
 
Publication

Assessment of the mean glandular dose using LiF:Mg,Ti, LiF:Mg,Cu,P, Li2B4O7:Mn and Li2B4O7:Cu TL detectors in mammography radiation fields

2016-08Journal article Restricted access
Simple item page
dc.contributor.authorFartaria, M. J.
dc.contributor.authorReis, Cláudia
dc.contributor.authorPereira, J.
dc.contributor.authorPereira, M. F.
dc.contributor.authorCardoso, J. V.
dc.contributor.authorSantos, L. M.
dc.contributor.authorOliveira, C.
dc.contributor.authorHolovey, V.
dc.contributor.authorPascoal, A.
dc.contributor.authorAlves, J. G.
dc.date.accessioned2016-12-22T12:38:41Z
dc.date.available2016-12-22T12:38:41Z
dc.date.issued2016-08
dc.description.abstractThe aim of this paper is the characterization of four thermoluminescence detectors (TLD), namely, LiF:Mg,Ti, LiF:Mg,Cu,P, Li2B4O7:Mn and Li2B4O7:Cu for the measurement of the entrance surface air kerma (ESAK) and estimation of the mean glandular dose (MGD) in digital mammography examinations at hospitals and clinics. Low-energy x-ray beams in the typical energy ranges of mammography, produced with a tungsten target and additional 60 µm molybdenum filtration were implemented and characterized at the Laboratory of Metrology of Ionizing Radiation at Instituto Superior Técnico. These beams were used for the characterization of the TLDs in terms of sensitivity, linearity, reproducibility, energy dependence and fading at 40 °C. The energy dependence test was further extended using clinical beams produced by mammography units at hospitals and clinics. The method proposed by the International Atomic Energy Agency was used for the measurement of ESAK and assessment of MGD. The combined standard uncertainty for the measurement of ESAK (and MGD) was determined in accordance to the Guide to the expression of uncertainty in measurement. The x-ray beams generated in the 23-40 kVp range presented HVL values from 0.36 to 0.46 mm Al. The beam produced at 28 kVp (HVL 0.39 mm Al) was considered as reference. The radiation field defined a circle with 84 mm diameter with a maximum variation of the beam intensity of less than 1% at the top flat (plateau) within 4 cm of the central axis. The estimated total uncertainty for the measurement of air kerma was 0.42%. All the TL detectors tested showed good performance except the commercial Li2B4O7:Mn (or TLD-800) which was excluded due to its poor sensitivity in our experimental set up. Both lithium fluorides showed better linearity and reproducibility as well as lower energy dependence and fading when compared to lithium borates. The stable behaviour of LiF:Mg,Ti and LiF:Mg,Cu,P detectors is reflected in the low combined standard uncertainty of  ±5.6% and  ±4.3% respectively (or  ±5.1% and  ±3.6% if fading is neglected). In general a total combined uncertainty lower than  ±10% for the measurement of ESAK was obtained for the four TL materials studied.pt_PT
dc.description.versioninfo:eu-repo/semantics/publishedVersionpt_PT
dc.identifier.citationFartaria MJ, Reis C, Pereira J, Pereira MF, Cardoso JV, Santos LM, et al. Assessment of the mean glandular dose using LiF:Mg,Ti, LiF:Mg,Cu,P, Li2B4O7:Mn and Li2B4O7:Cu TL detectors in mammography radiation fields. Phys Med Biol. 2016;61(17):6384-99.pt_PT
dc.identifier.doi10.1088/0031-9155/61/17/6384pt_PT
dc.identifier.urihttp://hdl.handle.net/10400.21/6661
dc.language.isoengpt_PT
dc.peerreviewedyespt_PT
dc.publisherIOP Publishingpt_PT
dc.relation.publisherversionhttp://iopscience.iop.org/article/10.1088/0031-9155/61/17/6384/meta;jsessionid=5EE6AD9AFA1C703A7EE3C2268E5C0247.c1.iopscience.cld.iop.orgpt_PT
dc.rights.urihttp://creativecommons.org/licenses/by-nc/4.0/pt_PT
dc.subjectRadiologypt_PT
dc.subjectMammographypt_PT
dc.subjectThermoluminescence detectorspt_PT
dc.subjectDosimetrypt_PT
dc.subjectMean glandular dosept_PT
dc.titleAssessment of the mean glandular dose using LiF:Mg,Ti, LiF:Mg,Cu,P, Li2B4O7:Mn and Li2B4O7:Cu TL detectors in mammography radiation fieldspt_PT
dc.typejournal article
dspace.entity.typePublication
oaire.citation.endPage6399pt_PT
oaire.citation.issue17pt_PT
oaire.citation.startPage6384pt_PT
oaire.citation.titlePhysics in Medicine and Biologypt_PT
oaire.citation.volume61pt_PT
rcaap.rightsrestrictedAccesspt_PT
rcaap.typearticlept_PT

Files

Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
Assessment of the mean glandular dose using LiF.pdf
Size:
518.78 KB
Format:
Adobe Portable Document Format
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Download

Collections

ESTeSL - Artigos