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Radionuclide Imaging in Treatment Planning
Published in W. P. M. Mayles, A. E. Nahum, J.-C. Rosenwald, Handbook of Radiotherapy Physics, 2021
Robust, repeatable and reproducible imaging protocols are crucial for the standardisation of quantitative delineation methods and decision making. Important steps in this direction have been taken in clinical trials within the Quantitative Imaging Network and the National Cancer Institute to improve the effectiveness of clinical trials of new cancer therapies. The Quantative Imaging Biomarkers Alliance (QIBA) has been established to identify requirements for biomarkers and then to try to obtain consensus for their use. QIBA profiles provide a structure for collaboration that may lead to agreed protocols. The aim is to improve quantification of the use of biomarkers across centres. Two initial examples of such developments are a protocol for using FDG PET-CT in oncology (QIBA 2014) and the development of diffusion-weighted magnetic resonance imaging (DW-MRI) (see Section 33.4.3) to measure the apparent diffusion coefficient (ADC) for brain, liver and prostate (QIBA 2017).
Pathology
Published in Burkhard Madea, Asphyxiation, Suffocation,and Neck Pressure Deaths, 2020
The most sensitive imaging examination is diffusion-weighted magnetic resonance imaging (DWI or DW-MRI). This imaging method uses the diffusion of water molecules to generate contrast in MR images. It maps the diffusion process of molecules, mainly water, and distinguishes between whether the accumulation of water within is intra- or inter-cellular. Consequently, it is possible to differentiate respectively between cytotoxic oedema (in which the blood−brain barrier is not disrupted, for example seen in cerebral ischaemia) and vasogenic oedema (in which the blood−brain barrier is disrupted, for example because of an abscess or a tumour).
Breast cancer
Published in Ruijiang Li, Lei Xing, Sandy Napel, Daniel L. Rubin, Radiomics and Radiogenomics, 2019
Diffusion-weighted magnetic resonance imaging (DWI) is another advanced MRI technique to measure the mobility of the water molecules diffusing in the tissue (21). It measures the Brownian motion of water molecules which indirectly reflects the tissue microstructure via the apparent diffusion coefficient (ADC).
Comparison of frequency of silent cerebral infarction as assessed by serum neuron specific enolase in patients with non-valvular atrial fibrillation: Warfarin versus direct oral anticoagulant
Published in Acta Cardiologica, 2023
Huseyin Goksuluk, Nil Ozyuncu, Irfan Veysel Duzen, Veysel Kutay Vurgun, Turkan Seda Tan, Sadi Gulec
Silent cerebral infarcts as detected with imaging modalities in non-valvular AF patients had been evaluated in several studies [21–25]. However, there were few studies regarding the difference in oral anticoagulant treatments and the occurrence of SCI. Two AF trials reported low SCI prevalance under warfarin treatment with different imaging modalities. Ezekowitz et al. [21] evaluated 516 patients with computed tomography (CT) and overall 14.7% of them had evidence of SCI in the warfarin treatment group (rate of 1.57% per year). Likewise, Strach and colleagues reported the prevalance of SCI in 3.9% of 51 patients with diffusion-weighted magnetic resonance imaging (DW-MRI) despite therapeutic anticoagulation [26]. The sensitivity of the diagnostic technique, definition of the SCI and the patient characteristics (e.g. age, sex, race and vascular risk factors) may contribute to the lower reported prevalence of SCI in the setting of these trials. Our study confirmed the increased rate of recent SCI by serum NSE elevation, a valid and sensitive biomarker for even minör neuronal injury [12]. Besides, our study was first to demonstrate that DOAC treatment may reduce SCI when compared to warfarin in patients with NVAF. Comparison of well-conducted warfarin treatment (TTR ≥ 60%) with DOACs treatment showed the reinforcement of the need for good quality anticoagulation to prevent cerebral ischaemic events, likewise in trials and real-world settings.
Incidentally found mucinous epithelial tumors of the appendix with or without pseudomyxoma peritonei: diagnostic and therapeutic algorithms based on current evidence
Published in Acta Chirurgica Belgica, 2021
Wim Ceelen, Marc De Man, Wouter Willaert, Gabrielle H. van Ramshorst, Karen Geboes, Anne Hoorens
Imaging includes a CT scan of the abdomen and chest to define the relevant anatomy and exclude lymph node and organ metastases. In patients with PMP, whole-body diffusion-weighted magnetic resonance imaging (DWI-MRI) allows accurate measurement of the peritoneal cancer index (PCI), which is used to quantify the extent of peritoneal disease [14]. Nuclear imaging such as 18F-FDG-PET-CT is relatively insensitive to low-grade mucinous neoplasms but may be indicated when the extra-abdominal disease is suspected in patients with high-grade adenocarcinoma.Colonoscopy is routinely indicated to exclude synchronous colorectal neoplasms [15]. In some patients, mucus may be observed at the orifice of the appendix, and this is a pathognomonic sign.Several retrospective studies have shown that elevated CEA and CA-19.9 have prognostic value in patients with appendiceal mucinous neoplasms [16,17].
Effects of butylphthalide injection on treatment of transient ischemic attack as shown by diffusion-weighted magnetic resonance imaging abnormality
Published in International Journal of Neuroscience, 2020
Chenhao Zhang, Yanjing Zang, Qin Song, Weidong Zhao, Hongxuan Li, Lei Hu, Qing Zhang, Fang Gu, Chunliang Zhang
Transient ischemic attack (TIA) is an early warning signal for cerebral infarction. Once TIA occurs, the risk of cerebral infarction is significantly increased. Previous studies [1–6] have shown that the risk of stroke is high in the early stage after TIA, with a rate of 4–10% in 7 days and 10–20% in 90 days. The ABCD2 scoring system for the risk of early stroke after TIA is used to predict short-term progression to stroke among patients with TIA. The recurrence risk of high-risk patients with an ABCD2 score of greater than three is more than 14% in 90 days. Important information on assessment of TIA can be provided by magnetic resonance imaging (MRI). The sensitivity and specificity of diffusion-weighted magnetic resonance imaging (DWI) are high in the early stage of cerebral ischemia. Using the ABCD2 score, the risk of early stroke after TIA can be assessed by an increase in seizure frequency in TIA with DWI [6]. Some studies [7,8] have reported that the incidence rate of patients with TIA and positive DWI findings ranges from 37% to 49%. Furthermore, the risk of cerebral infarction in patients with TIA and positive DWI findings is greater than that in patients with TIA and normal DWI findings [9–11].