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排序方式: 共有4716条查询结果,搜索用时 163 毫秒
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Jim Zhong Michael Gallagher Chris Hounslow Gareth Iball Tze Wah 《Diagnostic and interventional radiology (Ankara, Turkey)》2021,27(2):244
PURPOSEWe aimed to evaluate the effect on the radiation dose to the patient by reducing the tube current during the placement of the ablation needles (reduced dose group) compared with the patient doses delivered when scanning at the standard fully diagnostic level (full dose group) in computed tomography (CT)-guided percutaneous cryoablation.METHODSWe conducted a retrospective study of 103 patients undergoing cryoablation in a tertiary cancer center. Overall, 62 patients were scanned with standard exposure parameters (full dose group) set on a 64-slice multidetector CT scanner, while 41 patients were scanned on a reduced dose protocol. Dose levels were retrieved from the hospital picture and archiving communication system including the volumetric CT dose index (CTDIvol), total dose length product (DLP), length of cryoablation procedure, number of cryoablation needles and patient size. Wilcoxon Mann-Whitney (rank-sum) tests were used to compare the median DLP, CTDIvol and skin dose between the two groups.RESULTSMedian total DLP for the full dose group was 6025 mGy·cm (1909–13353 mGy·cm) compared with 3391 mGy·cm (1683–6820 mGy·cm) for the reduced dose group. The reduced dose group had a 44% reduction in total DLP and 42% reduction in total CTDIvol (p < 0.001). The estimated skin doses were 384 mGy for the full dose group and 224 mGy for the reduced dose group (42% reduction) (p < 0.001). At 12-month follow-up, the technical success for the full dose (n=62) was 97% with 2 patients requiring a further cryoablation treatment for residual tumor. The technical success for the reduced dose group (n=41) was 100%.CONCLUSIONCT dose reduction technique during image-guided cryoablation treatment of renal tumors can achieve significant radiation dose reduction whilst maintaining sufficient image quality.Renal cell carcinoma is the most common kidney cancer and has a rising incidence (1–4), with obesity and smoking being major risk factors (5–8).Image-guided ablation offers a more minimally invasive option compared with surgery and the current evidence base shows that it is a safe and effective treatment for T1a tumors, with a low rate of complications (9–11). The major advantage of cryoablation over other modalities is the ability to accurately visualize the iceball and therefore zone of ablation on intraprocedural imaging, either with computed tomography (CT) or magnetic resonance imaging (MRI) (12, 13). However, renal cryoablation involves the placement of more ablation probes and can have almost three times the radiation exposure compared with CT-guided radiofrequency ablation procedures (14).In addition to this substantial radiation dose per cryoablation, estimated to be between 32 and 39.7 mSv, the follow-up CT imaging will also add to the total radiation burden (15, 16). Whilst this level of radiation dose and associated stochastic risk may be a lesser concern in the older patients, greater consideration needs to be given to younger patients (<50 years old) and in patients requiring lifelong follow-up imaging, in particular those with hereditary diseases such as Von Hippel-Lindau syndrome (15). To our knowledge, the potential for reducing radiation dose for cryoablation patients.The principle aim of this study was to evaluate the effect on the radiation dose to the patient by reducing the tube current during the placement of the ablation needles (reduced dose group) compared with the patient doses delivered when scanning at the standard fully diagnostic level (full dose group) in CT-guided percutaneous cryoablation. 相似文献
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Soojung Hong Ju Hyun Lee Eun Kyeong Chun Kwang-Il Kim Jin Won Kim Se Hyun Kim Yun-Gyoo Lee In Gyu Hwang Jin Young Kim Su-Jin Koh Yoon Ho Ko Seong Hoon Shin In Sook Woo Tae-Yong Kim Ji Yeon Baek Hyun Jung Kim Hyo Jung Kim Myung Ah Lee Jung Hye Kwon Yong Sang Hong Hun-Mo Ryoo Jee Hyun Kim 《The oncologist》2020,25(3):e502-e511
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Kyung Won Lee Mi Sook Cho Dayeon Shin 《International journal of food sciences and nutrition》2016,67(2):184-194
Urinary iodine concentrations (UICs) in the US have been reported to be stable since 1988–1994, although those in selected subgroups remained low. We aimed to investigate iodine status among adults (≥20 years) by two different criteria of assessing iodine deficiency in population. Utilizing National Health and Nutrition Examination Surveys 2001–2012, we conducted linear logistic regressions adjusting for covariates. The prevalence of <50?μg/L UIC was higher in women than in men; increased from 11.6% (2001–2004) to 13.2% (2009–2012) at the national level and in young adults, non-Hispanic blacks (NHBs) and non-users of iodine-containing supplements (all, p?<0.05); the adjusted odds ratios (95%CI) in young adults (1.54 [1.11–2.15], p =?0.0007) and NHBs (1.70 [1.15–2.52], p =?0.0078). Median UICs confirm women and NHBs being in borderline iodine status. Recognizing the critical consequence of iodine deficiency particularly in women and NHBs, regular monitoring of iodine status is important for public health in the US. 相似文献
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Prospective cohort study on the outcomes of hepatitis C virus‐related cirrhosis in South Korea 下载免费PDF全文
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Quantitative anatomical analysis of facial expression using a 3D motion capture system: Application to cosmetic surgery and facial recognition technology 下载免费PDF全文
Hyung‐Jin Lee Jung‐Hyuk Seo You‐Jin Choi Hyun‐Sook Bae Jong‐Tae Park Hee‐Jin Kim 《Clinical anatomy (New York, N.Y.)》2015,28(6):735-744
The topography of the facial muscles differs between males and females and among individuals of the same gender. To explain the unique expressions that people can make, it is important to define the shapes of the muscle, their associations with the skin, and their relative functions. Three‐dimensional (3D) motion‐capture analysis, often used to study facial expression, was used in this study to identify characteristic skin movements in males and females when they made six representative basic expressions. The movements of 44 reflective markers (RMs) positioned on anatomical landmarks were measured. Their mean displacement was large in males [ranging from 14.31 mm (fear) to 41.15 mm (anger)], and 3.35–4.76 mm smaller in females [ranging from 9.55 mm (fear) to 37.80 mm (anger)]. The percentages of RMs involved in the ten highest mean maximum displacement values in making at least one expression were 47.6% in males and 61.9% in females. The movements of the RMs were larger in males than females but were more limited. Expanding our understanding of facial expression requires morphological studies of facial muscles and studies of related complex functionality. Conducting these together with quantitative analyses, as in the present study, will yield data valuable for medicine, dentistry, and engineering, for example, for surgical operations on facial regions, software for predicting changes in facial features and expressions after corrective surgery, and the development of face‐mimicking robots. Clin. Anat. 28:735–744, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Evelyn Xiu Ling Loo Hui Xing Lau Noor Hidayatul Aini Suaini Lydia Su Yin Wong Anne Eng Neo Goh Oon Hoe Teoh Hugo PS Van Bever Lynette Pei-chi Shek Bee Wah Lee Kok Hian Tan Keith M. Godfrey Johan Gunnar Eriksson Yap Seng Chong Elizabeth Huiwen Tham 《Pediatric allergy and immunology》2021,32(5):1096-1099
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Xin Yi Wong Andrew Qi Jun Lim Qianyu Shen John Whay Kuang Chia Min Hoe Chew Wah Siew Tan 《Current medical research and opinion》2020,36(10):1677-1686
Abstract