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- Alagic, Zlatan, et al.
(författare)
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First experiences of a low-dose protocol for CT-guided musculoskeletal biopsies combining different radiation dose reduction techniques
- 2020
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Ingår i: Acta Radiologica. - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 61:1, s. 28-36
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Tidskriftsartikel (refereegranskat)abstract
- Background The use of computed tomography (CT) for image guidance during biopsies is a powerful approach. The method is, however, often associated with a significant level of radiation exposure to the patient and operator. Purpose To investigate if a low-dose protocol for CT-guided musculoskeletal (MSK) biopsies, including a combination of different radiation dose (RD) techniques, is feasible in a clinical setting. Material and Methods Fifty-seven patients underwent CT-guided fine-needle aspiration cytology (FNAC) utilizing the low-dose protocol (group A). A similar number of patients underwent CT-guided FNAC using the reference protocol (group B). Between-group comparisons comprised radiation dose, success rate, image quality parameters, and workflow. Results In group A, the mean total dose-length product (DLP) was 41.2 +/- 2.9 mGy*cm, which was statistically significantly lower than of group B (257.4 +/- 22.0 mGy*cm), corresponding to a mean dose reduction of 84% (P<0.001). The mean CTDIvol for the control scans were 1.88 +/- 0.09 mGy and 13.16 +/- 0.40 mGy for groups A and B, respectively (P < 0.001). The success rate in group A was 91.2% and 87.9% in group B (P = 0.56). No negative effect on image-quality parameters, time of FNAC, and number of control scans were found. Conclusion We successfully developed a low-dose protocol for CT-guided MSK biopsies that maintains diagnostic accuracy and image quality at a fraction of the RD compared to the reference biopsy protocol at our clinic.
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| 2. |
- da Silva, Joakim, et al.
(författare)
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Resolution characterization of a silicon-based, photon-counting computed tomography prototype capable of patient scanning
- 2019
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Ingår i: Journal of Medical Imaging. - USA : SPIE - International Society for Optical Engineering. - 2329-4302 .- 2329-4310. ; 6:4
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Tidskriftsartikel (refereegranskat)abstract
- Photon-counting detectors are expected to bring a range of improvements to patient imaging with x-ray computed tomography (CT). One is higher spatial resolution. We demonstrate the resolution obtained using a commercial CT scanner where the original energy-integrating detector has been replaced by a single-slice, silicon-based, photon-counting detector. This prototype constitutes the first full-field-of-view silicon-based CT scanner capable of patient scanning. First, the pixel response function and focal spot profile are measured and, combining the two, the system modulation transfer function is calculated. Second, the prototype is used to scan a resolution phantom and a skull phantom. The resolution images are compared to images from a state-of-the-art CT scanner. The comparison shows that for the prototype 19 lp∕cm are detectable with the same clarity as 14 lp∕cm on the reference scanner at equal dose and reconstruction grid, with more line pairs visible with increasing dose and decreasing image pixel size. The high spatial resolution remains evident in the anatomy of the skull phantom and is comparable to that of other photon-counting CT prototypes present in the literature. We conclude that the deep silicon-based detector used in our study could provide improved spatial resolution in patient imaging without increasing the x-ray dose.
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