成人肺显像时组织吸收剂量及对患者的防护措施

脑显像是核医学诊断中的重要组成部分，临床诊断上应用很广，在诊断过程中，不同的疾病、不同的诊断方法，不同的试剂对患可能产生不同的吸收剂量。为了不使患接受不必要的辐射剂量，降低放射性核素诊断的风险，有必要采用包括阻吸收、促排、替代以及建立、健全诊断过程前中后的质量保证体系等措施来保护患。     

超声联合肌电诱发电位诊断战士臂丛训练伤临床应用

目的探讨采用超声联合肌电诱发电位诊断战士臂丛训练伤的临床效果。方法选取自2017年1—9月解放军208医院收治的军事训练过程中疑似臂丛神经损伤的53例战士为研究对象。所有患者均存在不同程度手部肌肉、肩胛、臂部等部位的麻痹症状,均行超声、肌电诱发电位及超声联合肌电诱发电位检查,根据诊断结果分别评估不同检查方式的诊断效果,比较不同检查方法诊断患者的灵敏度、特异性及诊断符合率。结果超声诊断灵敏度为81.1%(30/37),特异度为100.0%(16/16),诊断符合率为86.8%(46/53);肌电诱发电位诊断灵敏度为89.2%(33/37),特异度为87.5%(14/16),诊断符合率为88.7%(47/53);超声联合肌电诱发电位诊断灵敏度为97.3%(36/37),特异度为100.0%(16/16),诊断符合率为98.1%(52/53)。超声联合肌电诱发电位诊断灵敏度及诊断符合率均高于超声、肌电诱发电位检查,差异有统计学意义(P<0.05)。结论采用超声联合肌电诱发电位检查诊断臂丛损伤患者诊断准确率高,利于患者的早期诊治。     

内蒙古自治区常规X射线诊断患者剂量调查结果分析

目的 分析内蒙古地区常规X射线诊断患者入射体表剂量水平。方法 根据全国医疗照射剂量及频度调查项目方案的要求,完成内蒙古地区30%数量医疗机构常规X射线诊断应用现状调查,按照医疗机构年接诊人数比例抽取内蒙古地区12个盟市24家医疗机构开展普通X射线诊断患者入射体表剂量调查。将不同设备、不同级别医院、不同照射部位间受检者入射体表剂量结果进行比较。结果 在各类诊断设备中,以数字X射线摄影系统（DR）为主。在各类常规X射线诊断检查过程中,腰椎摄影所致患者平均入射体表剂量为3.39 mGy/人,骨盆及髋关节摄影检查所致患者平均入射体表剂量为1.65 mGy/人,颈椎、四肢和胸部摄影所致患者平均入射体表剂量分别为0.90、0.38、0.37 mGy/人。在胸部、腰椎、颈椎3种部位的诊断检查中,使用屏片摄影设备所致受检者入射体表剂量高于DR测量结果,差异具有统计学意义（Z=-3.229、-4.820、-5.265,P<0.05）。结论 屏片摄影设备所致患者的入射体表剂量大于DR,操作人员的操作行为是影响患者入射体表剂量的重要因素。     

循环miRNA在肿瘤诊治中的研究进展

微小RNAs（microRNAs,miRNAs）是一类内源性非编码小分子RNA,通过降解或抑制靶mRNA翻译,在转录后水平调节基因表达,广泛参与细胞分化、增殖、生长、凋亡等生理过程。近年来．存对多种肿瘤类型miRNA表达谱分析研究中发现miRNA的组织特异性和发育阶段特异性表达有助丁对疾病进行分类、诊断、分期和预后判断。最近,研究发现循环血液中存在稳定的miRNA分子,且肿瘤患者的循环核酸中存在源自肿瘤的miRNA分子,不同的肿瘤类型盛肿瘤的不同亚型都有不同的miRNA表达模式。这一发现开启了使用循环miRNA作为无创诊断肿瘤的新思路。     

多发性骨髓瘤的Ⅹ线CT及磁共振成像影像学表现研究

目的研究探讨多发性骨髓瘤(MM)的X线、CT及磁共振成像(MRI)的临床表现,并分析其各自的临床应用价值。方法选取我院2014年1月至12月收治的多发性骨髓瘤患者101例作为研究对象,回顾性分析患者的基本资料以及X线、CT、MRI影像学诊断结果,总结不同诊断方式的临床表现,计算其各自的诊断阳性率。结果观察患者的X线、CT、MRI影像学诊断结果,并将其与手术病理诊断结果进行对照,可见其各自的检出阳性率分别为64.4%、98.0%、100%,诊断灵敏度分别为64.6%、88.9%、98.0%,CT和MRI的检出阳性率及诊断灵敏度均显著高于X线,在诊断灵敏度上,MRI也显著高于CT,比较差异均有统计学意义(P<0.05)。结论CT和MRI在诊断多发性骨髓瘤的过程中,均有较高的检出率和诊断灵敏度,且MRI在空间定位上、病变损伤等方面的显示效果更佳,是理想的诊断方法。     

经阴道三维超声在诊断及治疗卵巢储备功能低下患者中的应用价值

目的探究经阴道三维超声在卵巢储备功能低下(DOR)患者诊断与治疗过程中的检测价值。方法选择疑似DOR患者120例为观察对象。以超声以及激素检查为诊断标准进行诊断。比较经阴道三维超声和二维超声分析卵巢体积(OV)、窦卵泡数(AFC)以及优势卵泡的差异。结果 120例患者中104例确诊为DOR,三维超声诊断的敏感性和特异性均为100%,二维超声诊断的敏感性为100%(104/104),特异性为68.8%(11/16)。三维超声检测的OV、AFC以及优势卵泡在不同时间点下的增长趋势较二维超声更平稳。二维超声记录的OV、AFC以及优势卵泡其标准差均大于三维超声,但差异无统计学意义(P0.05)。104例DOR患者治疗后三维超声均发现优势卵泡,二维超声有3例患者未发现优势卵泡。结论经阴道三维超声在DOR患者的诊断与治疗过程中的检测结果均强于二维超声。     

骨折病人放射诊断误诊232例原因分析

目的探讨骨折病人误诊原因,提出应对措施。方法对来自四川省、成都市不同地区不同等级医院11 611例伤残鉴定者进行复查,然后将原始诊断与本院检查诊断进行对比分析。结果 11 611例骨折患者中,有232例诊断与原结果不符,误诊率约2.0%。结论临床医师工作责任心、放射医师临床经验与摄片技术、设备性能、患者配合欠佳等因素是导致误诊的主要原因。     

体像障碍患者美容整形术后的回顾性诊断和分析

目的：回顾性分析、探讨美容整形手术受者中体像障碍患者的诊断、治疗和康复方法。 方法：美容整形术患者5000例的病历和图片资料,对符合体像障碍诊断的25例手术治疗前后的临床表现和康复过程进行统计、分析。     

脑出血DWI的诊断价值

目的探讨脑出血过程中扩散加权成像(DWI)信号演变规律及其诊断价值。方法32例自发性脑出血患者在1.5T磁共振仪行常规MRI和DWI检查。结果DWI在脑出血急性期(<24h)主要表现为高低混杂信号;亚急性早期(2～7d)主要表现为中央低边缘高信号的“晕征”;亚急性晚期(2～3周)表现多样;慢性期(>3周)表现为含铁血黄素低信号环或低信号。结论DWI在脑出血的不同时期、不同成分的信号表现不同,有助于出血的早期诊断和与脑梗塞的鉴别诊断。     

神经系统DSA检查技术对影像质量的影响

目的:通过2500例介入神经放射的检查及治疗,探讨DSA一些技术参数的设定对影像质量的影响。方法:使用美国GE公司AdvantxDLXLCN 和德国Siemens公司的NeurostarPlus两种目前最先进的数字减影血管造影系统,对中枢神经系统血管疾病进行介入诊断和治疗。治疗过程中根据不同需要,通过对各种不同参数的调节,得到最佳的影像质量。结果:通过对DSA机技术参数的调节,可提高血管影像质量。所有患者均能清晰显示病变,满足临床医生介入放射诊断和治疗的需要,减少患者的放射剂量。结论:DSA技术参数的调整对介入神经放射诊断和治疗起着至关重要的作用。     

CR床边胸部摄影吸收剂量的相关性研究

目的：评价CR床边胸部摄影对于患者的吸收剂量。方法：68例胸部X线摄影分别采用CR病房床边胸部摄影和DR在影像科进行胸部摄影两种不同的方式拍摄。CR床边胸部摄影采用68~76kVp进行前后位摄影。DR胸部摄影采用110~140kVp后前位进行摄影。用统计学方法对其X线吸收剂量进行评价。结果：在吸收剂量方面几种方法各不相同,CR床边胸部摄影与DR胸部摄影患者的随机吸收剂量无统计学差异。CR床边胸部摄影被检者与其邻近患者之间其吸收剂量有显著性差异。结论：DR胸部摄影患者的随机吸收剂量低于CR床边胸部摄影。     

Lung toxicity in radioiodine therapy of thyroid carcinoma: development of a dose-rate method and dosimetric implications of the 80-mCi rule.

Based on an extensive dataset analyzed by Benua et al., a whole-body retention threshold of 2.96 GBq (80 mCi) at 48 h has been used to limit the radioactivity of (131)I administered to thyroid cancer patients with diffuse pulmonary metastases. In this work, the 80-mCi activity retention limit is used to derive lung-absorbed doses and dose rates. The resulting dose-rate-based limits make it possible to account for patient-specific differences in lung geometry. This is particularly important, for example, in pediatric patients exhibiting diffuse lung metastases. The approach also highlights the impact of altered radioiodine kinetics as seen with recombinant human thyroid-stimulating hormone. METHODS: The dose-rate constraint (DRC) was defined as the absorbed dose rate to the lungs of the adult female reference phantom when 80 mCi of (131)I are in the body and 90% of this is uniformly distributed in the lungs. With this definition, the 80-mCi rule was generalized by calculating the activity required to yield a dose rate equal to DRC using lung-to-lung S factor values corresponding to different reference phantoms. RESULTS: A DRC value of 43.6 cGy/h was obtained. Applying this DRC to the adult male phantom and to the phantom of a 15-y-old yields equivalent 48-h activity limits of 3.72 GBq (101 mCi) and 2.45 GBq (66.2 mCi), respectively. Depending on model parameters, the absorbed doses to lungs ranged from 57 to 112 Gy; the photon-only portion, which better reflects the dose to normal lung parenchyma, ranged from 4.9 to 55 Gy. CONCLUSION: A dose-rate-based version of the 80-mCi rule is derived and used to demonstrate application of this rule to pediatric patients and to adult male patients. The implications of the 80-mCi rule are also examined. The assumption of uniform energy deposition in the lungs leads to substantially overestimated absorbed doses. Severe radiation-induced lung toxicity, expected at normal lung absorbed doses of 25-27 Gy, is avoided, probably because most of the local electron dose is delivered to tumor tissue instead of to normal lung parenchyma. The possibility of using a DRC to adjust treatment for different clinical situations is illustrated. The analysis suggests that a dosimetry-based approach will be particularly important in the treatment of patients with lung metastases when a recombinant human thyroid-stimulating hormone protocol is used.     

The tissue proton T1 and T2 response to gadolinium DTPA injection in rabbits. A potential renal contrast agent for NMR imaging

Three different doses of gadolinium (Gd) DTPA were administered intravenously to rabbits. Cardiovascular responses and changes in blood T1 and T2 were serially followed for 15 minutes when the animals were sacrificed for in vitro measures of tissue T1 and T2. Gd-DTPA was distributed and excreted like water soluble iodinated contrast agents with large changes in blood, urine, and kidney proton relaxation. An imaging experiment confirmed the efficacy as an NMR contrast agent for renal excretion. At effective doses, no adverse effects were observed and the agent appeared to be much safer than x-ray contrast agents, but with a similar potential for clinical utility.     

Comparison of non-coplanar and coplanar irradiation techniques to treat cancer of the pancreas

We compared two different techniques of pancreatic irradiation using measures associated with normal tissue complications. Seven consecutive patients with pancreatic cancer were planned for both coplanar and non-coplanar (NCP) external beam radiation treatments, using the same defined anatomical volumes for each patient, in each case. Each pair of plans was then compared using a range of objective criteria. Individual normal tissues were assessed against traditional tolerance limits. Selected dose-points, normal tissue complication probability (NTCP) and equivalent uniform doses (EUD) were also compared, as were indices combining information from individual tissues - total NTCP and total weighted EUD. All individual normal tissues doses were within established tolerance limits. For NCP relative to coplanar planning, NTCP and EUD were lower for all individual tissues in four cases and one case, respectively, i.e. in most cases a benefit to one tissue was offset by detriment to others. Summary measures demonstrated overall benefits for NCP techniques, with the total NTCP in six patients, and with the total weighted EUD in all patients. NCP techniques show potentially useful benefits. We present a new objective measure, the total weighted EUD, which may be particularly useful comparing plans where there are multiple critical tissues.     

库普弗细胞清道夫受体、CD14表达变化及其与内毒素性肝损伤的关系

目的　从细胞受体水平探讨内毒素性肝损伤过程中肝内库普弗细胞 (KC)由防御性逐步转化为效应性的机制。　方法　经尾静脉注射不同剂量内毒素 (LPS)复制轻、中、重度内毒素血症小鼠模型。肝内KC表面清道夫受体 (SR)、CD14表达测定采用免疫组化法 ,并进行计算机图像分析。　结果　注射LPS后 1h ,高剂量组肝内KC表面SR表达明显减少 ,至 3h ,低剂量和中剂量组KC表面SR表达也开始明显减少 ,并随观察时间延长 ,3组KC表面SR表达均进行性减少 ,3组间SR的吸光度差异有显著性意义。 3组肝内KC表面CD14表达在注射LPS后 1h均明显增多 ,并随时间延长而更加明显 ,但 3组间CD14的吸光度无统计学意义。相关分析显示 ,各剂量组肝内SR与CD14表达变化呈显著负相关。血浆丙氨酸氨基转移酶 (ALT)、总胆红素 (TB)和肝组织内丙二醛 (MDA)水平变化分别与SR表达下调呈显著负相关 ,与CD14表达上调呈显著正相关。肝组织结构改变及动物死亡率也与肝内KC表面SR、CD14表达变化呈明显的平行关系。　结论　内毒素致肝损伤过程中 ,肝内KC表面SR表达下调、CD14表达上调可能是KC防御功能减弱、致炎作用增强的重要机制。     

2017-2019年我国介入放射学工作人员眼晶状体剂量水平与分析

目的 调查2017-2019年我国介入放射学工作人员眼晶状体辐射剂量水平,掌握我国介入放射工作人员眼晶状体剂量水平现状.方法 通过国家个人剂量登记系统,采集我国28个省份介入放射学工作人员眼晶状体剂量监测数据,监测部位为左眼、评估指标为个人剂量当量Hp(3)、监测方法为热释光剂量计.分别运用Mann-Whitney U...     

The effects of pyridostigmine bromide on visual performance.

The effects of pyridostigmine bromide (PB) on selected visual functions were measured on four healthy aviator candidates. Following a pretreatment day during which baseline measurements were completed, subjects were administered currently recommended doses (30 mg, t.i.d.) of PB for 3 d during which their visual functions were assessed using a repeated measures design. Spatial resolution ability was evaluated with high and low contrast visual acuity charts and contrast sensitivity charts at three luminance levels. Dark adaptation was evaluated by measuring visual thresholds for 40 min after a standardized retinal photopigment bleach. Also, refractive error and several oculomotor functions (lateral phoria, fusional vergence, accommodative amplitude, and pupil size) were measured. On days that the subjects ingested PB, only refractive error and pupil diameter were significantly different, and these only minimally. We conclude that the use of PB at doctrinal doses will not significantly compromise an aviator's visual ability.     

Dosimetry with thermoluminescence during mammography

A dosimetry study using lithium fluoride TL dosimeters was carried out during mammography in 34 patients in order to evaluate in vivo the dose of mammography rays received by these patients. The measures are made for one breast only, using two views: cranio-caudal and medio-lateral views with compression. The results show that skin entrance doses are going from 0.20 to 1.67 cGy in cranio-caudal view and from 0.15 to 1.75 cGy in medio-lateral view. The skin exit doses are from 0.001 to 0.21 cGy in cranio-caudal view and from 0.001 to 0.13 cGy in medio-lateral view. The midplane doses estimated from the skin entrance dose and the graph of the deep yield are from 0.07 to 0.48 cGy. These doses are comparable with those founded by other authors, and though maximum, they stay very low. This is important for detect the breast cancer in order to reduce radiation risks.     

Cumulative radiation doses from recurrent PET–CT examinations

Positron emission tomography (PET–CT) is an essential imaging modality for the management of various diseases. Increasing numbers of PET–CT examinations are carried out across the world and deliver benefits to patients; however, there are concerns about the cumulative radiation doses from these examinations in patients. Compared to the radiation exposure delivered by CT, there have been few reports on the frequency of patients with a cumulative effective radiation dose of ≥100 mSv from repeated PET–CT examinations. The emerging dose tracking system facilitates surveys on patient cumulative doses by PET–CT because it can easily wrap up exposure doses of PET radiopharmaceuticals and CT. Regardless of the use of a dose tracking system, implementation of justification for PET–CT examinations and utilisation of dose reduction measures are key issues in coping with the cumulative dose in patients. Despite all the advantages of PET/MRI such as eliminating radiation exposure from CT and providing good tissue contrast in MRI, it is expensive and cannot be introduced at every facility; thus, it is still necessary to utilise PET–CT with radiation reduction measures in most clinical situations.