PRFS

PRF
  • 文章类型: Journal Article
    磁共振测温法(MRT)可以实时且无创地测量体内3D温度变化。然而,对于口咽区域和整个头部和颈部,运动可能会引入大的伪影。考虑到60-90分钟的长处理时间,本研究旨在评估口咽周围的MRT在热疗治疗中是否具有临床可行性,并量化呼吸和吞咽对MRT表现的影响.3D-ME-FGRE序列用于在约75分钟内冷却五名志愿者的口咽周围的幻影。成像协议包括加速成像(ARC=2),图像平均数(NEX=1、2和3)。对于志愿者来说,这些采集包括屏气扫描和故意吞咽扫描。对颈部肌肉的MRT性能进行了量化,脊髓和咬肌,使用平均平均误差(MAE),平均误差(ME)和空间标准偏差(SD)。在幻影中,NEX的增加导致SD的显着降低,但MAE和我没有改变。在不同扫描之间的志愿者中没有发现显著差异。评估的区域之间存在显着差异:颈部肌肉具有最佳的MAE(=1.96°C)和SD(=0.82°C),其次是脊髓(MAE=3.17°C,SD=0.92°C)和咬肌(MAE=4.53°C,SD=1.16°C)。关于我,脊髓做得最好,然后是颈部肌肉和咬肌,值为-0.64°C,分别为1.15°C和-3.05°C。呼吸,吞咽,和不同的成像方式(加速度和NEX)不会显着影响口咽区域的MRT性能。然而,选择的ROI,导致显著差异。
    Magnetic resonance thermometry (MRT) can measure in-vivo 3D-temperature changes in real-time and noninvasively. However, for the oropharynx region and the entire head and neck, motion potentially introduces large artifacts. Considering long treatment times of 60-90 min, this study aims to evaluate whether MRT around the oropharynx is clinically feasible for hyperthermia treatments and quantify the effects of breathing and swallowing on MRT performance. A 3D-ME-FGRE sequence was used in a phantom cooling down and around the oropharynx of five volunteers over ∼75 min. The imaging protocol consisted of imaging with acceleration (ARC = 2), number of image averages (NEX = 1,2 and 3). For volunteers, the acquisitions included a breath-hold scan and scans with deliberate swallowing. MRT performance was quantified in neck muscle, spinal cord and masseter muscle, using mean average error (MAE), mean error (ME) and spatial standard deviation (SD). In phantom, an increase in NEX leads to a significant decrease in SD, but MAE and ME were unchanged. No significant difference was found in volunteers between the different scans. There was a significant difference between the regions evaluated: neck muscle had the best MAE (=1.96 °C) and SD (=0.82 °C), followed by spinal cord (MAE = 3.17 °C, SD = 0.92 °C) and masseter muscle (MAE = 4.53 °C, SD = 1.16 °C). Concerning the ME, spinal cord did best, then neck muscle and masseter muscle, with values of -0.64 °C, 1.15 °C and -3.05 °C respectively. Breathing, swallowing, and different ways of imaging (acceleration and NEX) do not significantly influence the MRT performance in the oropharynx region. The ROI selected however, leads to significant differences.
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  • 文章类型: Journal Article
    背景:患者报告的结果测量(PROM)是个体身体功能和情绪健康的自我反映。埃德蒙顿症状评估量表(ESAS)是一种简单且经过验证的PRO工具,包含10种常见症状和患者报告的功能状态(PRFS)度量。该工具在胃食管癌(GEC)患者中的预后价值尚不清楚。在这项研究中,我们检查了GEC患者的ESAS评分与总生存期(OS)之间的关系,ESAS和东部肿瘤协作组(ECOG)的预后差异,并评估PRFS与医生报告的ECOG表现状态(PS)之间的相关性。
    方法:本研究是一项回顾性队列研究,纳入了211例患有局部(I-III期)和转移性疾病的GEC患者,这些患者在治疗前至少完成了一次基线ESAS。根据ESAS评分将患者分为3个队列。OS使用Kaplan-Meier方法进行评估,并计算ESAS和医师报告的ECOG的一致性指数(c指数)。还评估了PRFS和医师-ECOG之间的协议。
    结果:总计,包括211名患者。中位年龄为60.8岁;90%的患者为ECOGPS0-1;38%的患者为I-III期,而62%为从头转移患者。OS中位数低,中度,高症状负担(SB)患者队列为19.17m,16.39mm,和12.68米,分别(P<.04)。医师-ECOG和ESAS(c指数分别为0.56和0.5753)与PRFS和医师-ECOG(c指数分别为0.5615和0.5545)预测死亡的能力相似。患者和医生之间的PS一致性为50%,加权Kappa为0.27(95%CI:0.17-0.38)。
    结论:患者的SB似乎具有预后意义。ESAS和医生报告的ECOG具有相当的预后价值。医生和患者经常对PS有不同的意见。ESAS采取以患者为中心的方法,在实践中应鼓励GEC患者作为预后的附加工具。
    BACKGROUND: Patient-reported outcomes measures (PROM) are self-reflections of an individual\'s physical functioning and emotional well-being. The Edmonton Symptom Assessment Scale (ESAS) is a simple and validated PRO tool of 10 common symptoms and a patient-reported functional status (PRFS) measure. The prognostic value of this tool is unknown in patients with gastroesophageal cancer (GEC). In this study, we examined the association between the ESAS score and overall survival (OS) in patients with GEC, the prognostication difference between ESAS and Eastern Cooperative Oncology Group (ECOG), and assessed the correlation between PRFS and the physician-reported ECOG performance status (PS).
    METHODS: The study was a retrospective cohort study of 211 patients with GEC with localized (stages I-III) and metastatic disease who completed at least one baseline ESAS prior to treatment. Patients were grouped into 3 cohorts based on ESAS score. OS was assessed using the Kaplan-Meier method, and the concordance index (c-index) was calculated for ESAS and physician-reported ECOG. The agreement between PRFS and physician-ECOG was also assessed.
    RESULTS: In total, 211 patients were included. The median age was 60.8 years; 90% of patients were ECOG PS 0-1; 38% of patients were stages I-III, while 62% were de novo metastatic patients. Median OS in low, moderate, high symptom burden (SB) patients\' cohorts was 19.17 m, 16.39 mm, and 12.68 m, respectively (P < .04). The ability to predict death was similar between physician-ECOG and ESAS (c-index 0.56 and 0.5753, respectively) and PRFS and physician-ECOG (c-index of 0.5615 and 0.5545, respectively). The PS agreement between patients and physicians was 50% with a weighted Kappa of 0.27 (95% CI: 0.17-0.38).
    CONCLUSIONS: Patient\'s SB seems to carry a prognostic significance. ESAS and physician-reported ECOG exhibit comparable prognostic values. Physicians and patients can frequently have divergent opinions on PS. ESAS takes a patient-centered approach and should be encouraged in practice among patients with GEC as an additional tool for prognostication.
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  • 文章类型: Journal Article
    生物炭因其具有吸附和催化性能,是一种有前途的环境污染物修复剂。然而,对生物质热解(生物炭生产)产生的持久性自由基(PFRs)的环境影响仍然知之甚少,尽管近年来它们受到了越来越多的研究关注。虽然PFRs直接和间接地介导生物炭对环境污染物的去除,它们也有可能造成生态破坏。为了支持和维持生物炭的应用,需要有效的策略来控制生物炭PFRs的负面影响。然而,没有对环境行为进行系统的评估,风险,或生物炭PFRs的管理技术。因此,本文综述:1)概述了生物炭PFRs的形成机理和类型,2)评估其环境应用和潜在风险,3)总结了他们的环境迁移和转型,和4)探索了生物炭PFRs在生产和应用阶段的有效管理策略。最后,提出了未来的研究方向。
    Biochar is a promising environmental contaminant remediation agent because of its adsorptive and catalytic properties. However, the environmental effects of persistent free radicals (PFRs) produced by biomass pyrolysis (biochar production) are still poorly understood, though they have received increasing research attention in recent years. Although PFRs both directly and indirectly mediate biochar\'s removal of environmental pollutants, they also have the potential to cause ecological damage. In order to support and sustain biochar applications, effective strategies are needed to control the negative effects of biochar PFRs. Yet, there has been no systematic evaluation of the environmental behavior, risks, or management techniques of biochar PFRs. Thus, this review: 1) outlines the formation mechanisms and types of biochar PFRs, 2) evaluates their environmental applications and potential risks, 3) summarizes their environmental migration and transformation, and 4) explores effective management strategies for biochar PFRs during both production and application phases. Finally, future research directions are recommended.
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  • 文章类型: Journal Article
    热疗治疗的功效取决于良好控制的加热;因此,准确的温度监测对于确保有效治疗至关重要。对于深盆腔热疗,没有关于MR测温的全面和系统的报告。此外,数据纳入通常缺乏客观的选择标准,导致在比较结果时出现偏差的可能性很高。在这里,我们研究了基于成像的数据纳入是否能预测准确性,并可作为前瞻性患者选择的工具.局部晚期宫颈癌患者MR测温的准确性以腔内温度为基准。我们发现在治疗开始时的胃肠空气运动,由Jaccard相似系数量化,是MR测温精度的良好预测指标。与所有患者的结果相比,选择用于低胃肠空气运动的组的结果改善了50%(准确性),26%(精度),和80%(偏差)。我们发现,当考虑所有患者时,平均MR测温精度为2.0°C,而选定组的平均MR测温精度为1.0°C。这些结果是对新技术进行全面基准测试的基础。Jaccard相似系数也具有很好的潜力,可以前瞻性地确定MR测温法在哪些患者中很有价值。
    The efficacy of a hyperthermia treatment depends on the delivery of well-controlled heating; hence, accurate temperature monitoring is essential for ensuring effective treatment. For deep pelvic hyperthermia, there are no comprehensive and systematic reports on MR thermometry. Moreover, data inclusion generally lacks objective selection criteria leading to a high probability of bias when comparing results. Herein, we studied whether imaging-based data inclusion predicts accuracy and could serve as a tool for prospective patient selection. The accuracy of the MR thermometry in patients with locally advanced cervical cancer was benchmarked against intraluminal temperature. We found that gastrointestinal air motion at the start of the treatment, quantified by the Jaccard similarity coefficient, was a good predictor for MR thermometry accuracy. The results for the group that was selected for low gastrointestinal air motion improved compared to the results for all patients by 50% (accuracy), 26% (precision), and 80% (bias). We found an average MR thermometry accuracy of 2.0 °C when all patients were considered and 1.0 °C for the selected group. These results serve as the basis for comprehensive benchmarking of novel technologies. The Jaccard similarity coefficient also has good potential to prospectively determine in which patients the MR thermometry will be valuable.
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  • 文章类型: Journal Article
    为了证明交错MR测温法可以以足够的时间分辨率监测水和脂肪中的温度。这与高强度聚焦超声(HIFU)治疗骨病变有关,通常在水组织附近发现,作为肌肉,或嵌入脂肪组织中,皮下脂肪和骨髓.
    随着时间交替地获取基于质子共振频率偏移(PRFS)的测温扫描和基于T1的2D可变翻转角(2D-VFA)测温扫描。使用PRFS测温法监测水中的温度,并通过具有切片轮廓效应校正的2D-VFA测温法在脂肪中。在MR-HIFU超声处理期间研究了在猪骨骼中离体监测水/脂肪温度的可行性。在非加热条件下,在健康志愿者中评估了体内测量的准确性和稳定性。
    该方法允许观察肌肉和脂肪的温度随时间的变化,包括骨髓,在MR-HIFU超声处理期间,时间分辨率为6.1s。在体内,在实验的时间尺度上,表观温度变化是稳定的:在7分钟内,肌肉中的系统漂移<0.042°C/min(漂移校正后的PRFS)和骨髓中的系统漂移<0.096°C/min(2D-VFA)。随时间平均的温度变化的SD为0.98°C(PRFS)和2.7°C(2D-VFA)。
    交错MR测温法可以测量水和脂肪中的温度,其时间分辨率足够高,可用于监测HIFU消融。具体来说,脂肪和水的联合测温法提供了有关靠近骨皮质的组织温度变化的不间断信息。
    To demonstrate that interleaved MR thermometry can monitor temperature in water and fat with adequate temporal resolution. This is relevant for high intensity focused uUltrasounds (HIFU) treatment of bone lesions, which are often found near aqueous tissues, as muscle, or embedded in adipose tissues, as subcutaneous fat and bone marrow.
    Proton resonance frequency shift (PRFS)-based thermometry scans and T1 -based 2D variable flip angle (2D-VFA) thermometry scans were acquired alternatingly over time. Temperature in water was monitored using PRFS thermometry, and in fat by 2D-VFA thermometry with slice profile effect correction. The feasibility of interleaved water/fat temperature monitoring was studied ex vivo in porcine bone during MR-HIFU sonication. Precision and stability of measurements in vivo were evaluated in a healthy volunteer under non-heating conditions.
    The method allowed observing temperature change over time in muscle and fat, including bone marrow, during MR-HIFU sonication, with a temporal resolution of 6.1 s. In vivo, the apparent temperature change was stable on the time scale of the experiment: In 7 min the systematic drift was <0.042°C/min in muscle (PRFS after drift correction) and <0.096°C/min in bone marrow (2D-VFA). The SD of the temperature change averaged over time was 0.98°C (PRFS) and 2.7°C (2D-VFA).
    Interleaved MR thermometry allows temperature measurements in water and fat with a temporal resolution high enough for monitoring HIFU ablation. Specifically, combined fat and water thermometry provides uninterrupted information on temperature changes in tissue close to the bone cortex.
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  • 文章类型: Journal Article
    BACKGROUND: Symptom palliation is an important objective of treatment in advanced/metastatic lung cancer (LC). Significant psychological, minor physical symptoms and several social/emotional issues often go unnoticed. This prospective study aimed to evaluate utility of patients\' perspectives [self-reported symptom assessment by revised Edmonton Symptom Assessment System (ESAS-r) and self-reported functional status by Patient-Reported Functional Status (PRFS)] amongst LC patients undergoing chemotherapy.
    METHODS: Consecutive newly diagnosed treatment-naïve LC patients attending a tertiary referral center in North India from January 2014 to March 2015 were included. All patients received standard histology-guided platinum-doublet chemotherapy. ESAS-r and PRFS questionnaires were administered under guidance, once at the time of initial assessment/diagnosis, repeated at start of chemotherapy, before C4, and after completion of chemotherapy (end of chemotherapy (EOCTx)). Functional Assessment of Cancer Therapy-Lung (FACT-L) questionnaire was also administered. Baseline and post-treatment scores were compared.
    RESULTS: Majority of 133 patients enrolled were males (86.5%,n = 115), were current/ex-smokers (81.2%, n = 108), had advanced stage [IIIB = 30.1% (n = 40), IV = 52.6% (n = 70)], and were of non-small-cell type (NSCLC;84.2%,n = 112). On baseline ESAS-r, the highest mean symptom scores were observed for tiredness followed by anorexia. Mean ESAS-r scores before C4 as well as at EOCTX were significantly better than baseline ESAS-r scores in all its components except nausea. Similarly, PRFS before C4 and EOCTx was significantly improved compared to baseline. However, Karnofsky Performance Scale (KPS) and Eastern Cooperative Oncology Group Performance Status assessed at baseline did not show significant improvement at treatment completion. FACT-L score at EOCTx showed significant improvement from baseline in physical and functional well-being domains but not for social/family and emotional well-being domains.
    CONCLUSIONS: This study validated utility of ESAS-r and PRFS in Indian LC patients. These instruments should be used in routine clinical practice besides physicians\' assessment of PS (KPS/ECOG).
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  • 文章类型: Journal Article
    BACKGROUND: Because protons in fat do not exhibit a temperature-dependent frequency shift, proton resonance frequency shift (PRFS)-based MR thermometry always suffers from disturbances due to the presence of fats or lipids.
    OBJECTIVE: A new fat suppression method for PRFS-based MR thermometry is proposed to obtain accurate variation of phase angle.
    METHODS: Similar to the approach of separating fat and water with the two-point Dixon technique, we first scan a complex MR image for reference and then scan another complex image varying with temperature at the same TE point. Based on the conventional PRFS method, we use geometric relationships to remove the effect of fat on the variation of the phase angle.
    RESULTS: Two phantoms with different water-to-fat ratios are involved in the temperature mapping test. Experimental results show that the temperature images of two phantoms are approximated under the same conditions.
    CONCLUSIONS: The proposed fat suppression method is simple and effective for PRFS-based MR thermometry.
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  • 文章类型: Journal Article
    背景:磁共振(MR)引导的高强度聚焦超声已成为姑息治疗疼痛性骨转移的临床选择,与MR测温(MRT)用于治疗监测。在这项研究中,根据信噪比(SNR)和表观温度变化对MRT的总体图像质量进行评估.此外,对MRT伪影的发生和阻碍治疗监测进行评分。
    方法:对从13个处理中检索到的224个MRT数据集进行分析。信噪比是在幅度图像中随时间测量的每个体素,在目标病变和周围肌肉中,并平均每次治疗。MRT图像中每个体素的测量温度随时间的标准偏差,在加热区域之外的肌肉中,定义为表观温度变化,并对每个处理进行平均。评分的MRT伪影来自以下来源:呼吸和非呼吸随时间变化的场不均匀性,动脉重影,通过肌肉收缩和全身运动来实现患者的运动。在病变类型之间进行了区分,location,和程序镇静和镇痛(PSA)。
    结果:溶骨性病变及其周围的平均SNR最高(病变为21,27在周围肌肉中,n=4),上身最低(病变为9,16在周围肌肉中,n=4)。溶骨性病变的平均表观温度变化最低(1.2°C,n=4),上身最高(1.7°C,n=4)。呼吸随时间变化的场不均匀性MRT伪影发生在85%的数据集中,并阻碍了81%的治疗监测。非呼吸时变场不均匀性和动脉重影MRT伪影最常见(94%和95%),但仅在局部发生。患者运动伪影变化很大,在使用异丙酚和艾氯胺酮作为PSA的溶骨性病变治疗中发生率较低。
    结论:在这项研究中,MRT的一般图像质量在溶骨性病变中观察到较高,在上半身较低。呼吸随时间变化的场不均匀性是最突出的MRT伪影。患者的运动发生在治疗之间有所不同,并且似乎与病变类型和PSA类型有关。临床医生在解释MRT图像时应该意识到这些观察到的特征。
    BACKGROUND: Magnetic resonance (MR)-guided high-intensity focused ultrasound has emerged as a clinical option for palliative treatment of painful bone metastases, with MR thermometry (MRT) used for treatment monitoring. In this study, the general image quality of the MRT was assessed in terms of signal-to-noise ratio (SNR) and apparent temperature variation. Also, MRT artifacts were scored for their occurrence and hampering of the treatment monitoring.
    METHODS: Analyses were performed on 224 MRT datasets retrieved from 13 treatments. The SNR was measured per voxel over time in magnitude images, in the target lesion and surrounding muscle, and was averaged per treatment. The standard deviation over time of the measured temperature per voxel in MRT images, in the muscle outside the heated region, was defined as the apparent temperature variation and was averaged per treatment. The scored MRT artifacts originated from the following sources: respiratory and non-respiratory time-varying field inhomogeneities, arterial ghosting, and patient motion by muscle contraction and by gross body movement. Distinction was made between lesion type, location, and procedural sedation and analgesic (PSA).
    RESULTS: The average SNR was highest in and around osteolytic lesions (21 in lesions, 27 in surrounding muscle, n = 4) and lowest in the upper body (9 in lesions, 16 in surrounding muscle, n = 4). The average apparent temperature variation was lowest in osteolytic lesions (1.2°C, n = 4) and the highest in the upper body (1.7°C, n = 4). Respiratory time-varying field inhomogeneity MRT artifacts occurred in 85% of the datasets and hampered treatment monitoring in 81%. Non-respiratory time-varying field inhomogeneities and arterial ghosting MRT artifacts were most frequent (94% and 95%) but occurred only locally. Patient motion artifacts were highly variable and occurred less in treatments of osteolytic lesions and using propofol and esketamine as PSA.
    CONCLUSIONS: In this study, the general image quality of MRT was observed to be higher in osteolytic lesions and lower in the upper body. Respiratory time-varying field inhomogeneity was the most prominent MRT artifact. Patient motion occurrence varied between treatments and seemed to be related to lesion type and type of PSA. Clinicians should be aware of these observed characteristics when interpreting MRT images.
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