Characteristics of an OSLD in the diagnostic energy range

Abstract

OSLDs exhibited good batch homogeneity (<5%) and reproducibility (3.3%), as well as a linear response. In addition, they showed no statistically significant difference with TLDs in CT measurements (p > 0.1). However, high uncertainty (42%) in the dose estimate was found as a result of relatively high accumulated dose. Furthermore, nanoDots showed high angular dependence (up to 70%) in low kVp techniques. Energy dependence of about 60% was found, and correction factors were suggested for the range of energies investigated. Therefore, if angular and energy dependences are taken into consideration and the uncertainty associated with accumulated dose is avoided, OSLDs (nanoDots) can be suitable for use as point dosimeters in diagnostic settings.

The effective dose of different scanning protocols using the Sirona GALILEOS®comfort CBCT scanner

“…OSLDs are more dependent on incident beam angle than are TLDs. 12 While this effect is readily observed with a fixed beam, it is less pronounced in CT exposure 12 report an effect of ,10% for a wide angular range of CT exposures at 80 kVp. If we assume that all of these angles occur internally in the RANDO phantom, this uncertainty would only account for a variation of 5% relative to the calibration exposure of OSLDs laid flat.…”

“…The aluminium content of the OSLDs causes a strong energy and orientation dependence at kilovoltage energies. 11,12 In total, 26 OSLDs were used in the RANDO phantom throughout the study. All dosemeters were individually calibrated using a Therapax HF150 superficial radiation therapy X-ray unit (Pantak, East Haven, CT) operated at 85 kVp with a composite filter [1.1 mm of aluminium (Al) and 0.3 mm of copper] Figure 1 The Therapax HF 150 unit (Pantak, East Haven, CT) is operated at 85 kVp with aluminium-copper filter in place and a Farmer Chamber (Capintec, Ramsay, NJ) at a depth of 6 cm in a polymethyl methacrylate phantom.…”

Radiation Doses in Patient Eye Lenses during Interventional Neuroradiology Procedures

“…Their small size makes them suitable for use near patients' eyes. OSLDs have been previously used to measure patient doses in different clinical situations, [10][11][12] but when used with diagnostic energies, special attention must be paid to limitations such as energy and angular dependence.…”

A Post-Mastectomy Radiation Therapy Dose Distribution Study

“…Four nanoDots were placed above the bolus, between the layers, and below the bolus, as shown in Figure 3(b) and Figure 3(c). Three control nanoDots were placed on chest wall to quantify imaging dose [24]. The phantom was scanned using CT simulator (Somatom, Siemens Medical Systems Inc., Malvern, PA) with both nanoDots and film in place.…”