| 1. |
- Ceberg, Sofie, et al.
(author)
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Surface guided radiotherapy decreases the uncertainty in breast cancer patient setup
- 2018
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Conference paper (peer-reviewed)abstract
- (Sunday, 7/29/2018) 3:00 PM - 6:00 PMRoom: Exhibit HallPurpose: The aim was to investigate if the setup of breast cancer patients could be improved using surface guided radiotherapy, compared to the conventional method using lasers and skin markings.Methods: Forty-seven patients, who received tangential or locoregional adjuvant radiotherapy, were positioned using a surface-based setup (SBS). Thirty-eight patients were positioned using the conventional laser-based setup (LBS). For the patient group positioned using a SBS, correction for posture was performed under guidance of a color map projected onto the patients' skin in real time. The surface tolerance for the color map was 5 mm. For both setup techniques the deviation of the breast position was measured using verification images. In total, 897 images were analysed. The frequency distributions of the deviations were analysed.Results: The result showed a significant improvement in the interfractional variation of the setup deviation for SBS compared to the LBS (pConclusion: Conventional laser-based setup can be replaced by surface-based setup, both for tangential and locoregional breast cancer treatments.
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| 2. |
- Johnson, Louis Banka, et al.
(author)
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Radiation enteropathy and leucocyte-endothelial cell reactions in a refined small bowel model
- 2004
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In: BMC Surgery. - : Springer Science and Business Media LLC. - 1471-2482. ; 4
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Journal article (peer-reviewed)abstract
- BACKGROUND: Leucocyte recruitment and inflammation are key features of high dose radiation-induced tissue injury. The inflammatory response in the gut may be more pronounced following radiotherapy due to its high bacterial load in comparison to the response in other organs. We designed a model to enable us to study the effects of radiation on leucocyte-endothelium interactions and on intestinal microflora in the murine ileum. This model enables us to study specifically the local effects of radiation therapy. METHOD: A midline laparotomy was performed in male C57/Bl6 mice and a five-centimetre segment of ileum is irradiated using the chamber. Leucocyte responses (rolling and adhesion) were then analysed in ileal venules 2 - 48 hours after high dose irradiation, made possible by an inverted approach using intravital fluorescence microscopy. Furthermore, intestinal microflora, myeloperoxidase (MPO) and cell histology were analysed. RESULTS: The highest and most reproducible increase in leucocyte rolling was exhibited 2 hours after high dose irradiation whereas leucocyte adhesion was greatest after 16 hours. Radiation reduced the intestinal microflora count compared to sham animals with a significant decrease in the aerobic count after 2 hours of radiation. Further, the total aerobic counts, Enterobacteriaceae and Lactobacillus decreased significantly after 16 hours. In the radiation groups, the bacterial count showed a progressive increase from 2 to 24 hours after radiation. CONCLUSION: This study presents a refinement of a previous method of examining mechanisms of radiation enteropathy, and a new approach at investigating radiation induced leucocyte responses in the ileal microcirculation. Radiation induced maximum leucocyte rolling at 2 hours and adhesion peaked at 16 hours. It also reduces the microflora count, which then starts to increase steadily afterwards. This model may be instrumental in developing strategies against pathological recruitment of leucocytes and changes in intestinal microflora in the small bowel after radiotherapy.
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| 3. |
- Jönsson, Mattias, et al.
(author)
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Technical evaluation of a laser-based optical surface scanning system for prospective and retrospective breathing adapted computed tomography.
- 2015
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In: Acta Oncologica. - 1651-226X. ; 54:2, s. 261-265
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Journal article (peer-reviewed)abstract
- Background. For breathing adapted radiotherapy, the same motion monitoring system can be used for imaging and triggering of the accelerator. Purpose. To evaluate a new technique for prospective gated computed tomography (CT) and four-dimensional CT (4DCT) using a laser based surface scanning system (Sentinel(™), C-RAD, Uppsala, Sweden). The system was compared to the AZ-733V respiratory gating system (Anzai Medical, Tokyo, Japan) and the Real-Time Position Management System (RPM(™)) (Varian Medical Systems, Palo Alto, CA, USA). Material and methods. Temporal accuracy was evaluated using a moving phantom programmed to move a platform along trajectories following a sin(6)(ωt) function with amplitudes from 6 to 20 mm and periods from 2 to 5 s during 120 s while the motion was recorded. The recorded data was Fourier transformed and the peak area at the fundamental and harmonic frequencies compared to data generated using the same sinusoidal function. For verification of the 4DCT reconstruction process, the phantom was programmed to move along a sinusoidal trajectory. Ten phase series were reconstructed. The distance from the couch to the platform was measured in each image. By fitting the function sin(ωt-ϕ) to the values measured in the images corresponding to each slice, the phase of each image was verified. Results and conclusion. In the recorded data, the peak area at the fundamental frequency covered on average 104 ± 4%, 102 ± 4% and 91 ± 27% of the peak area in the generated data for the Sentinel(™), RPM(™) and AZ-733V systems, respectively. All systems managed to resolve both harmonic frequencies. The second experiment showed that all images were sorted into the correct series using breathing data recorded by each system. The systems generated very similar results, however, it is preferable to use the same system both for imaging and treatment.
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| 4. |
- Jönsson, Mattias, et al.
(author)
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Technical evaluation of different motion-monitoring systems for respiratory gating in radiation therapy
- 2013
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In: Medical Physics in the Baltic States. - 1822-5721. ; , s. 38-41
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Conference paper (peer-reviewed)abstract
- The purpose of this work was to evaluate three motion-monitoring systems: Sentinel (TM), Catalyst (TM) (both C-RAD) and Real-time Position Management (RPM (TM)) system (Varian Medical Systems Inc) for respiratory gating in radiotherapy. To measure the systems. latency, an in-house built circuit with a microcontroller operating a piston was used. The trigger pulse was sent from the gating systems to the accelerator within 300 mu s. However, the response time of the accelerator could be over 300 ms
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| 5. |
- Kügele, Malin, et al.
(author)
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Surface guided radiotherapy (SGRT) improves breast cancer patient setup accuracy
- 2019
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In: Journal of Applied Clinical Medical Physics. - : Wiley. - 1526-9914. ; , s. 61-68
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Journal article (peer-reviewed)abstract
- Purpose: The purpose of the study was to investigate if surface guided radiotherapy (SGRT) can decrease setup deviations for tangential and locoregional breast cancer patients compared to conventional laser-based setup (LBS). Materials and Methods: Both tangential (63 patients) and locoregional (76 patients) breast cancer patients were enrolled in this study. For LBS, the patients were positioned by aligning skin markers to the room lasers. For the surface based setup (SBS), an optical surface scanning system was used for daily setup using both single and three camera systems. To compare the two setup methods, the patient position was evaluated using verification imaging (field images or orthogonal images). Results: For both tangential and locoregional treatments, SBS decreased the setup deviation significantly compared to LBS (P < 0.01). For patients receiving tangential treatment, 95% of the treatment sessions were within the clinical tolerance of ≤ 4 mm in any direction (lateral, longitudinal or vertical) using SBS, compared to 84% for LBS. Corresponding values for patients receiving locoregional treatment were 70% and 54% for SBS and LBS, respectively. No significant difference was observed comparing the setup result using a single camera system or a three camera system. Conclusions: Conventional laser-based setup can with advantage be replaced by surface based setup. Daily SGRT improves patient setup without additional imaging dose to breast cancer patients regardless if a single or three camera system was used.
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| 6. |
- Polistena, Andrea, et al.
(author)
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Local radiotherapy of exposed murine small bowel : Apoptosis and inflammation
- 2008
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In: BMC Surgery. - : Springer Science and Business Media LLC. - 1471-2482. ; 8
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Journal article (peer-reviewed)abstract
- Background. Preoperative radiotherapy of the pelvic abdomen presents with complications mostly affecting the small bowel. The aim of this study was to define the features of early radiation-induced injury on small bowel. Methods. 54 mice were divided into two groups (36 irradiated and 18 sham irradiated). Animals were placed on a special frame and (in the radiated group) the exteriorized segment of ileum was subjected to a single absorbed dose of 19 or 38 Gy radiation using 6 MV high energy photons. Specimens were collected for histology, immunohistochemistry (IHC) and ELISA analysis after 2, 24 and 48 hours. Venous blood was collected for systemic leucocyte count in a Burker chamber. Results. Histology demonstrated progressive infiltration of inflammatory cells with cryptitis and increased apoptosis. MIP-2 (macrophage inflammatory protein) concentration was significantly increased in irradiated animals up to 48 hours. No significant differences were observed in IL-10 (interleukin) and TNF-α (tumour necrosis factor) levels. IHC with CD45 showed a significant increase at 2 hours of infiltrating leucocytes and lymphocytes after irradiation followed by progressive decrease with time. Caspase-3 expression increased significantly in a dose dependent trend in both irradiated groups up to 48 hours. Conclusion. Acute small bowel injury caused by local irradiation is characterised by increased apoptosis of crypt epithelial cells and by lymphocyte infiltration of the underlying tissue. The severity of histological changes tends to be dose dependent and may affect the course of tissue damage.
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| 7. |
- Rääf, Christopher, et al.
(author)
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Human metabolism of radiocaesium revisited
- 2004
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In: Radiation Protection Dosimetry. - : Oxford University Press (OUP). - 1742-3406 .- 0144-8420. ; 112:3, s. 395-404
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Journal article (peer-reviewed)abstract
- Three adult volunteers (2 males and I female) have ingested radioactive caesium in two edible forms in order to compare the gastrointestinal uptake and the subsequent short-term and long-term biokinetics. Foodstuffs made of fresh-water fish or mushrooms from regions in Sweden of high Cs-137 deposition was ingested together with a (CsCl)-Cs-134-solution mixed with soft drinks. Whole-body countings of Cs-134 and Cs-137 were performed in the Malmo whole-body counter during a period of similar to50 d prior to, and 200-300 d after the ingestion. Urine and faeces were collected the day before and up to 7-10 d after the test meals, and analysed for Cs-134 and Cs-137. No significant difference in the gastrointestinal uptake fraction, f(0) = 0.98 between caesium incorporated into a foodstuff matrix and caesium in ionic form was detected. Cumulated faecal excretion during 7 d after ingestion accounted for 2-3% of the intake. No significant difference in the long-term biological half-time was found between caesium present in a food matrix and in an aqueous solution in any of the volunteers.
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| 8. |
- Rääf, Christopher, et al.
(author)
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Urinary excretion measurements for the assessment of body burden of radiocaesium in man: differences between potassium and creatinine normalisation
- 1999
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In: Applied Radiation and Isotopes. - 0969-8043. ; 51:5, s. 505-514
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Journal article (peer-reviewed)abstract
- Relationships between 24-h urinary excretion and body burden of 137Cs obtained in a south-Swedish population, together with data from the literature, were applied to urine samples collected in 1994-95 from adult subjects living in Russia, in order to estimate their average body burden of 137Cs. Estimates obtained through creatinine normalisation of the 137Cs content in the Russian urine were a factor of 2 higher than estimates obtained through potassium normalisation. The accuracy of both these normalisation methods is discussed, as well as the influence of the difference in dietary habits between the two populations.
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| 9. |
- Röme, Andrada, et al.
(author)
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Critical Role of P-Selectin and Lymphocyte Function Antigen-1 in Radiation-Induced Leukocyte-Endothelial Cell Interactions in the Colon.
- 2007
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In: Diseases of the Colon & Rectum. - : Ovid Technologies (Wolters Kluwer Health). - 0012-3706. ; 50:12, s. 2194-2202
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Journal article (peer-reviewed)abstract
- Purpose Radiation therapy is frequently used in treating different types of tumors, although associated with serious side effects, such as fibrosis and complicated diarrhea. This study was designed to define the adhesive mechanisms behind radiotherapy-induced leukocyte recruitment in the colon. Methods All mice, except control animals, were radiated with a single dose of 20 Gy. Mice were pretreated with an isotype-matched control antibody or a monoclonal antibody directed against P-selectin. In separate experiments, lymphocyte function antigen-1–deficient animals were used. Leukocyte rolling and firm adhesion were determined by use of inverted intravital fluorescence microscopy 16 hours after radiation. Results It was found that immunoneutralization of P-selectin reduced leukocyte rolling by 83 percent and adhesion by 87 percent in radiated mice. Moreover, radiation-induced leukocyte adhesion in LFA-1-deficient mice was decreased by 94 percent compared with wild-type animals. Conclusions This study demonstrates that leukocyte rolling is mediated by P-selectin and that firm leukocyte adhesion is supported by lymphocyte function antigen-1 in radiation-induced enteritis. Moreover, P-selectin-dependent leukocyte rolling is a precondition for subsequent leukocyte adhesion in radiation-induced intestinal injury. Thus, targeting P-selectin and/or lymphocyte function antigen-1 may protect against pathologic inflammation in the colon induced by radiotherapy.
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| 10. |
- Röme, Andrada, et al.
(author)
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Radiation-induced platelet-endothelial cell interactions are mediated by P-selectin and P-selectin glycoprotein ligand-1 in the colonic microcirculation.
- 2012
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In: Surgery. - : Elsevier BV. - 1532-7361 .- 0039-6060. ; 151:4, s. 606-611
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Journal article (peer-reviewed)abstract
- BACKGROUND: Antiplatelet reagents have been reported to protect against intestinal damage associated with abdominal radiotherapy, but the mechanisms behind radiation-induced platelet-endothelium interactions are not known. We sought to define the adhesive mechanisms that regulate radiotherapy-induced platelet-endothelial cell interactions in the colon. METHODS: All mice except the controls were exposed to abdominal radiation with a single dose of 20 Gray. Mice were pretreated with an isotype-matched control antibody or a monoclonal antibody directed against either P-selectin or P-selectin glycoprotein ligand-1 (PSGL-1). Platelet and leukocyte rolling and adhesion in the colon were determined by use of inverted intravital fluorescence microscopy 16 hours after radiation. Radiation-induced intestinal leakage of fluorescein isothiocyanate-conjugated dextran was examined in separate experiments. RESULTS: Immunoneutralization of P-selectin decreased radiation-provoked platelet rolling by 87% and adhesion by 63%. Moreover, inhibition of PSGL-1 decreased platelet rolling and adhesion by 77% and 83%, respectively, in animals exposed to radiation. Similarly, inhibition of P-selectin and PSGL-1 decreased radiation-induced leukocyte rolling and adhesion by more than 84% and 90%, respectively, in the colon. In contrast, inhibition of P-selectin or PSGL-1 had no impact on radiation-induced intestinal leakage. In addition, systemic depletion of platelets and leukocytes did not affect intestinal barrier dysfunction in radiated animals. CONCLUSION: This study demonstrates that radiation-provoked platelet and leukocyte accumulation are mediated in part by P-selectin and PSGL-1. Radiation-induced gut leakage, however, is independent of accumulation of platelets and leukocytes in the intestinal microvasculature.
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