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1.
《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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目的探讨多元化联合教学模式在超声引导下疼痛介入治疗教学中的应用效果。方法选择2018年1月至2020年12月在北京大学第三医院疼痛科进修的30名医师作为研究对象,将其分为对照组与观察组;对照组采用常规教学模式;观察组采用多元化联合教学模式,比较两组医师技能考核成绩、教学质量评分和满意度评分。结果观察组医师技能考核成绩优良率为93.3%,高于对照组的73.3%(P<0.05);观察组医师对基础理论知识掌握、临床思维能力的提高、学习兴趣的激发、疾病诊治能力的提高4个方面的评分均高于对照组(P<0.01)。结论多元化联合教学模式可促进超声引导下疼痛介入治疗技能的提高,有利于提高学员的综合临床能力。 相似文献
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《Journal of pediatric and adolescent gynecology》2020,33(6):748-751
BackgroundObstructed hemivagina and ipsilateral renal anomaly (OHVIRA) syndrome is usually diagnose during adolescence due to pain-related symptoms; however, this syndrome can go unrecognized for several years, and unique presentations may occur later in life.CaseWe describe a 24-year-old-woman diagnosed with previously unknown OHVIRA syndrome and a 7-week intrauterine pregnancy in the obstructed side by the unique ultrasound image obtained during routine first-trimester ultrasonography. The patient was managed with single-stage vaginoplasty, and the rest of the pregnancy were uneventful.Summary and ConclusionThis report is unique in terms of showing that the pregnancy could develop in the uterine cavity on the side of the obstruction despite the blind hemivagina. 相似文献
5.
Aliyah Hussein Kiran Sran Imran Ali Janine Woellner Helen Wilcox Stephen D. Marks Helen Jones Chris Callaghan 《Pediatric transplantation》2020,24(4)
Transplant ureteric stent insertion reduces the incidence of MUCs, but it is not known whether routine PSRGU is needed to detect unmasked MUCs. This study evaluated whether routine PSRGU in the pRTR is a useful tool to identify MUCs before they become clinically apparent. A retrospective analysis was undertaken of the clinical outcomes following elective stent removal from pediatric kidney‐only transplant recipients at two London centers between 2012 and 2016. Our policy was to perform PSRGU either routinely or urgently if there were concerning symptoms or biochemical evidence of renal allograft dysfunction. Elective stent removal was performed in 86% (97 of 113 pRTR), and 75 (77%) of whom had routine PSRGU at a median (IQR) of 6 (2‐8) days after stent removal. There were changes to management in 3 (4%) of pRTR with PSRGU identifying no MUC. Nineteen patients (25%) had urgent PSRGU, most commonly due to renal allograft dysfunction, at a median (IQR) of 5.5 (2.7‐12.3) days after stent removal. Of these, two pRTR required ureteric intervention. For our current practice of removing transplant stents at 4‐6 weeks post‐transplantation, our study has found no evidence to support routine PSRGU after elective stent removal. 相似文献
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郭永华 《临床超声医学杂志》2019,21(2)
目的:总结后颅窝正常和异常的胎儿小脑及小脑蚓部的矢状面的声像学特征,了解小脑细微结构的改变与胎儿畸形的关系。 相似文献
8.
Aaron Pitzele Mohammad Rahimi Eric Armbrecht 《The journal of maternal-fetal & neonatal medicine》2015,28(15):1770-1773
Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion. 相似文献
9.
《Clinical neurophysiology》2020,131(4):859-865
ObjectiveWe examined selected peripheral and spinal nerves of children aged between two and seven years.MethodHigh resolution ultrasound was performed in 116 children (2–7 years of age) at 19 predefined landmarks of median, ulnar, tibial, fibular, sural and radial nerves, the vagus as well as cervical spinal nerve 5 and 6. Further, side-to-side measuring and grey-scale analysis was done at selected nerve sites.ResultsNerves of children were on average smaller than those of adults. Nerve growth correlates significantly with age in all nerves, the mean values were similar in the age of two to four years and five to seven years. Body mass index (BMI) and gender showed moderate effect at some nerve sites, however not uniformly in all. A side-to-side difference of up to 30% in median, and up to 20% in tibial nerve can occur in healthy individuals. Grey-scale analysis for echointensity has been performed in median, ulnar and tibial nerves.ConclusionNerve size increases with age, BMI and gender have moderate effect. A side-to-side-difference of up to 30% can exist.SignificanceReference values of nerve cross-sectional area, side-to-side-difference and echo intensity are necessary to detect nerve pathology in children as well as in adults. 相似文献
10.
目的 探讨电视辅助胸腔镜下解剖性肺切除治疗Ⅰ期肺癌的临床效果。方法 采用回顾性研究方法,选取2015年5月至2017年1月广西医科大学附属肿瘤医院收治的I期肺癌患者84例,按照手术方法不同将患者分为两组:观察组和对照组,每组各42例。观察组患者实施电视辅助胸腔镜下解剖性肺切除术治疗,对照组患者给予传统开胸肺叶切除术治疗。比较两组患者的住院时间、切口长度、术中出血量、手术时间、1年和3年生存情况及生活质量评分(SF-36生活量表)变化。结果 观察组患者的住院时间短于对照组(6. 13±1. 46 vs. 10. 39±2. 41 d),切口长度小于对照组(4. 38±1. 09 vs. 11. 84±3. 25 cm),术中出血量少于对照组(284. 62±54. 21 vs. 397. 57±61. 49 ml),差异均具有统计学意义(P <0. 05);而两组手术时间比较(165. 28±33. 24 vs. 156. 39±30. 92 min),差异无统计学意义(P> 0. 05)。观察组患者的1、3年生存率[97. 62%(41/42)、90. 48%(38/42)]均高于对照组[88. 10%(37/42)、76. 19%(32/42)],但差异无统计学意义(P> 0. 05)。观察组患者的各项生活质量评分[精神健康(75. 42±6. 87 vs 61. 30±4. 15分)、情感职能(81. 38±7. 15 vs. 73. 49±5. 76分)、社会功能(82. 67±5. 78 vs. 75. 42±4. 35分)、一般健康状况(79. 49±6. 17 vs.70. 31±5. 04分)、精力(84. 37±5. 45 vs. 74. 13±6. 07分)、生理职能(86. 52±6. 88 vs. 76. 93±6. 42分)、躯体疼痛(83. 46±7. 49 vs. 74. 33±5. 79分)、生理功能(70. 39±4. 31 vs. 61. 38±3. 56分)]均高于对照组,且差异具有统计学意义(P <0. 05)。结论 与传统开胸肺叶切除术相比,电视辅助胸腔镜下解剖性肺切除治疗I期肺癌手术损伤更小、短期生存率更高,且有助于提高患者术后生活质量水平,这对改善患者预后有重要意义,值得临床推广应用。 相似文献