Assessment of female breast dose for thoracic cone-beam CT using MOSFET dosimeters

Abstract

Objective: To assess the breast dose during a routine thoracic cone-beam CT (CBCT) check with the efforts to explore the possible dose reduction strategy.Materials and Methods: Metal oxide semiconductor field-effect transistor (MOSFET) dosimeters were used to measure breast surface doses during a thorax kV CBCT scan in an anthropomorphic phantom. Breast doses for different scanning protocols and breast sizes were compared. Dose reduction was attempted by using partial arc CBCT scan with bowtie filter. The impact of this dose reduction strategy on image registration accuracy was investigated.Results: The average breast surface doses were 20.02 mGy and 11.65 mGy for thoracic CBCT without filtration and with filtration, respectively. This indicates a dose reduction of 41.8% by use of bowtie filter. It was found 220° partial arc scanning significantly reduced the dose to contralateral breast (44.4% lower than ipsilateral breast), while the image registration accuracy was not compromised.Conclusions: Breast dose reduction can be achieved by using ipsilateral 220° partial arc scan with bowtie filter. This strategy also provides sufficient image quality for thorax image registration in daily patient positioning verification.

Monte Carlo-based software for 3D personalized dose calculations in image-guided radiotherapy

“…Previous studies reported comparable dose for breast IGRT, varying from 1 to 10 mGy in the heart, breasts and lungs for one kV-CBCT [6] , [13] , [14] , [15] . In agreement with those studies, the different kV-CBCT user protocols in the head and neck and thoracic cohorts of our study showed that reducing the acquisition amplitude from a complete to a partial rotation combined to a reduced charge allowed to preserve organs (breasts for a thoracic CBCT or eyes for head and neck CBCT in case of a posterior arc).…”

Application of 3D-print silica bolus for nasal NK/T-cell lymphoma radiation therapy

“…MOSFET is a metal oxide semiconductor field-effect transistor, which has a submicron dosimetric volume and allows dosimeters to be used in a confined space like the nasopharyngeal cavity to measure radiation dose [ 17 ]. MOSFETs are also very suitable for measuring the surface dose [ 18 ]. Therefore, MOSFETs were used to measure the spot dose on the skin surface of the anthropomorphic head phantom.…”

Cone-Beam Computed Tomography vs. Multi-Slice Computed Tomography in paleoimaging: where we stand

“…Cone Beam Computed Tomography (CBCT) is a three-dimensional (3D) X-ray imaging technology, which was developed in the early 1980s (Robb 1982). CBCT was initially applied to angiography, and subsequently introduced for otorhinolaryngology, musculoskeletal, breast, respiratory, and cardiac applications (Ejima et al, 2010;Cakli et al, 2012;Sun et al, 2017;Nardi et al, 2018;Posadzy et al, 2018). The introduction of CBCT to maxillofacial imaging in the late 1990s led to fast diffusion of the technique, which now finds application in implantology, maxillary bones fractures, temporomandibular joint disorders, periodontology, and endodontics (Horner et al, 2015).…”