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《Radiography》2022,28(3):663-667
IntroductionAnti-scatter grids efficiently reduce scatter radiation from reaching the imaging receptor, enhancing image quality; however, the patient radiation dose increases in the process. There is disagreement regarding the thickness thresholds for which anti-scatter grids are beneficial. This study aims to establish a thickness threshold for the use of anti-scatter grids to optimise adult knee radiography.MethodsThe study consisted of two phases. In Phase 1 phantom knee radiographs were acquired at varying thicknesses (10–16 cm) and tube voltages (60–80 kV). For each thickness and tube voltage, images with and without an anti-scatter grid were obtained. In Phase 2, two radiologists and three radiographers, evaluated the image quality of these images. Visual Grading Analysis (VGA) scores were analysed using Visual Grading Characteristics (VGC) based on the visualisation of five anatomic criteria.ResultsThe average DAP decreased by 72.1% and mAs by 73.1% when removing the anti-scatter grid. The VGC revealed that overall images taken with an anti-scatter grid have better image quality (AUC ≥0.5 for all comparisons). However, the anti-scatter grids could be removed for thicknesses 10, 12 and 14 cm in conjunction with using 80 kVp,.ConclusionAnti-scatter grids can be removed when imaging adult knees between 10 and 12 cm using any kVp setting since the radiation dose is reduced without significantly affecting image quality. For thicknesses >12 cm, the use of anti-scatter grids significantly improves image quality; however, the radiation dose to the patient is increased. The exception is at 14 cm used with 80 kVp, where changes in image quality were insignificant.Implications for practiceOptimisation by removing anti-scatter grids in adult knee radiography seems beneficial below 12 cm thickness with any kVp value. Since the average knee thickness ranges between 10 and 13 cm, anti-scatter grid can be removed for most patients. Nevertheless, further studies are recommended to test if this phantom-based threshold applies to human subjects. 相似文献
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《Biology of blood and marrow transplantation》2019,25(12):e375-e386
Successful treatment of various hematologic diseases with allogeneic hematopoietic stem cell transplantation is often limited due to the occurrence of acute graft-versus-host disease (aGVHD). So far, there are no approved molecular biomarkers for the diagnosis and prediction of aGVHD at the clinical level due to our incomplete understanding of the molecular biology of the disease. Various studies have been conducted on animal models and humans to investigate the role of microRNAs in aGVHD pathogenesis to implicate them as biomarkers and therapeutic targets. Because of their high stability, tissue specificity, ease of measurement, low cost, and simplicity, they are excellent targets for biomarkers. In this review, we focused on microRNA expression profiling studies that were performed recently in both animal models and human cases of aGVHD to identify diagnostic and predictive biomarkers for this disease. The expression pattern of microRNAs can be specific to cells and tissues. Because aGVHD affects several organs, microRNA signatures in target tissues may help to understand the molecular pathology of the disease. Identification of organ-specific microRNAs in aGVHD can be promising to categorize patients for organ-specific therapies. Thus, microRNAs can be used as noninvasive diagnostic tests in clinic to improve prophylaxis, predict incidence and severity, and reduce morbidity. 相似文献
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《Clinical Lymphoma, Myeloma & Leukemia》2022,22(11):e981-e991
Over the years, a rising incidence of liver cirrhosis and lymphoma has been observed. Therefore, the risk of having cirrhosis as a comorbidity increases, thus challenging treatment approaches as data on the management of these patients is lacking. We performed a systematic review to summarize papers that analyzed patients with liver cirrhosis that occurred before and/or concomitantly to lymphoma. We identified 153 papers (230 patients) through Pubmed and/or Embase search. Publications comprised predominantly of case reports and/or case series. Most patients had HCV-related cirrhosis (62.6%), and aggressive lymphoma histology (59.6%). Data on liver status was available in 55.7% of all patients, with 46.1% having decompensated liver cirrhosis. These patients experienced more often treatment reductions and/or modifications, treatment side effects, and inferior survival than those with compensated cirrhosis (median 18 months vs. median not reached). Dose reductions and/or treatment modifications primarily due to concomitant liver disease were common. Moreover, liver toxicity was observed in 33.6% of patients with provided information on treatment side effects, ranging from mild toxicity to liver failure with fatal outcomes. Again, despite treatment modification/reduction, patients with decompensated liver cirrhosis developed hepatic toxicity more frequently than patients with compensated liver disease. Although patients suffering from cirrhosis and lymphoma can tolerate standard chemoimmunotherapy, a cautious multidisciplinary approach is needed to evaluate the risks and benefits. 相似文献
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To investigate the feasibility of arterial spin labeling (ASL) blood flow (BF) and its histogram analysis to distinguish early-stage nasopharyngeal carcinoma (NPC) from nasopharyngeal lymphoid hyperplasia (NPLH).Sixty-three stage T1 NPC patients and benign NPLH patients underwent ASL on a 3.0-T magnetic resonance imaging system. BF histogram parameters were derived automatically, including the mean, median, maximum, minimum, kurtosis, skewness, and variance. Absolute values were obtained for skewness and kurtosis (absolute value of skewness [AVS] and absolute value of kurtosis [AVK], respectively). The Mann–Whitney U test, receiver operating characteristic curve, and multiple logistic regression models were used for statistical analysis.The mean, maximum, and variance of ASL BF values were significantly higher in early-stage NPC than in NPLH (all P < 0.0001), while the median and AVK values of early-stage NPC were also significantly higher than those of NPLH (all P < 0.001). No significant difference was found between the minimum and AVS values in early-stage NPC compared with NPLH (P = 0.125 and P = 0.084, respectively). The area under the curve (AUC) of the maximum was significantly higher than those of the mean and median (P < 0.05). The AUC of variance was significantly higher than those of the other parameters (all P < 0.05). Multivariate analysis showed that variance was the only independent predictor of outcome (P < 0.05).ASL BF and its histogram analysis could distinguish early-stage NPC from NPLH, and the variance value was a unique independent predictor. 相似文献
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《Clinical oncology (Royal College of Radiologists (Great Britain))》2022,34(7):472-479
AimsTreatment decisions for older patients with breast cancer are complex and evidence is largely extrapolated from younger populations. Frailty and comorbidity need to be considered. We studied the baseline characteristics and treatment decisions in older patients in Christchurch with breast cancer and assessed survival outcomes and prognostic/discriminatory performance of several tools.Materials and methodsWe searched the Canterbury Breast Cancer Registry and identified patients aged 70 years or older at diagnosis with invasive, non-metastatic breast cancer between 1 June 2009 and 30 June 2015. We retrieved demographics, treatment and outcome information. Overall survival and breast cancer-specific survival were estimated. Tools analysing performance status and comorbidity were assessed for their prognostic and discriminatory power.ResultsIn total, 440 patients were identified. Primary surgery was carried out for 362 patients (82.3%): breast-conserving surgery in 114 (of whom 88.6% received radiation therapy); mastectomy in 248 (of whom 24.6% received radiation). Hormone therapy was given for 265 (71.1%) patients with oestrogen receptor-positive cancers. Two hundred and seventy-four (62.3%) patients received full standard treatment, which was associated with significantly improved 5-year survival and 5-year breast cancer-specific survival. The median estimated overall survival was 8.2 years (95% confidence interval 7.3–9.1 years). Of those who died, 71.3% of deaths were due to causes other than breast cancer or unknown causes. The comorbidity-adjusted life expectancy (CALE) showed partial prognostic accuracy. CALE, Charlson and Eastern Cooperative Oncology Group tools all showed discriminatory value.ConclusionIn this population-based series of older patients with breast cancer, showing high levels of primary and adjuvant treatment, patients were more likely to die of causes other than breast cancer. Performance status and comorbidity tools showed prognostic and discriminatory potential in this population supporting their use in treatment decision making. CALE showed the most potential to improve treatment decisions but requires validation in this population to improve prognostic accuracy. 相似文献