An optically stimulated luminescence system to measure dose profiles in x-ray computed tomography

Abstract

This paper describes an LED-based optically stimulated luminescence (OSL) system for dose profile measurements using OSL detector strips and investigates its performance in x-ray computed tomography (CT) dosimetry. To compensate for the energy response of the Al(2)O(3):C OSL detectors, which have an effective atomic number of 11.28, field-specific energy correction factors were determined using two methods: (a) comparing the OSL profiles with ionization chamber point measurements (0.3 cm(3) ionization chamber) and (b) comparing the OSL profiles integrated over a 100 mm length with 100 mm long pencil ionization chamber measurements. These correction factors were obtained for the CT body and head phantoms, central and peripheral positions and three x-ray tube potential differences (100 kVp, 120 kVp and 140 kVp). The OSL dose profiles corrected by the energy dependence agreed with the ionization chamber point measurements over the entire length of the phantom (300 mm). For 120 kVp x-ray tube potential difference, the CTDI(100) values calculated using the OSL dose profiles corrected for the energy dependence and those obtained from an independent measurement with a 100 mm long pencil ionization chamber also agreed within +/-5%.

Optically Stimulated Luminescent Dosimetry for High Dose Rate Brachytherapy

“…OSL has been employed for film dosimetry (Schembri and Heijmen, 2007), computed tomography (CT) dosimetry (Yukihara et al, 2009; Ruan et al, 2010), personal dosimetry monitoring (Akselrod et al, 1999; Lee and Lee, 2001; Yukihara and McKeever, 2008), and space dosimetry (McKeever, 2002). In OSL materials, crystal-lattice imperfections are introduced to trap electrons, which are liberated by ionizing radiation (Akselrod et al, 1990; Akselrod et al, 1999; Yukihara and McKeever, 2008).…”

Highly sensitive Europium doped SrSO4 OSL nanophosphor for radiation dosimetry applications

“…Carbon doped alumina (Al 2 O 3 :C) is the most popular phosphor material with the highest potential for OSL dosimetry due to its excellent dosimetric properties [1,2]. The application of OSL property of a-Al 2 O 3 :C single crystal has been established in personnel dosimetry [3,4], environmental dosimetry [5], medical dosimetry [6][7][8][9] and space dosimetry [10,11]. Although many OSL phosphors have been developed for dosimetric applications, the research is mainly centered on natural/synthetic quartz, feldspars, oxides, fluorides, chlorides etc.…”

“…[12][13][14][15][16]. More recently, OSL of borate and silicates doped with Ce, Eu, Sm and Cu ions have been reported [8][9][10][11][12]. Attempts are also made to study materials like BeO [17], NaMgF 3 :Eu [18], MgO:Tb [19], LiMgPO 4 :Tb,B [20], LiAlO 2 [21], YAG:C [22], Cu doped Alkali fluorosilicates [23][24][25], Li 3 PO 4 :Cu [26], SiO 2 :Ag [27], KBr:Eu [28], (NH 4 ) 2 SiF 6 :Tl [29], LiAlO 2 :Tb,Ce [30,31], ZnAl 2 O 4 :Tb [32], MgAl 2 O 4 :Tb [33] etc.…”

Characterization of optically stimulated luminescence dosemeters to measure organ doses in diagnostic radiology

“…Optically stimulated luminescence (OSL) dosimetry is another technique that is employed in many areas of radiation dosimetry, including personal monitoring, in vivo dosimetry and for generating dose profiles in the estimation of CT dose index (CTDI). [1][2][3] TLDs require complicated handling to read the device under fully controlled temperature changes and they employ sophisticated methods to thermally anneal the TLDs for reuse. 4 OSL dosemeters (OSLDs) have now been used for monitoring occupational radiation doses for more than a decade.…”