兴趣区设置对Gates法测定肾小球滤过率的影响

目的:探讨肾脏及本底兴趣区ROI的勾画方式对Gates法测定肾小球滤过率(GFR)的影响.方法:对41例患者行肾动态显像,并按不同ROI勾画法计算GFR.改变本底ROI位置、大小、本底与肾脏ROI距离及肾脏ROI大小、局部偏离,观察GFR变化;将各GFR与标准Gates法GFR比较,观察结果偏离程度及导致结果偏离的因素.结果:①logistic多因素分析表明,本底ROI位置、大小、本底与肾脏ROI间距离以及"肾脏ROI大小、局部偏离"均是影响GFR的重要因素(χ2分别为250.9,73.9,53.5,215.8,P=0.000);②本底位于肾脏正下方较大范围内或肾脏ROI在外下方局部外偏时GFR与标准Gates法十分接近;本底ROI、肾脏ROI的其它各种改变均可对GFR产生较大程度的影响.结论:①Gates法GFR测定时,ROI勾画须注意多种影响因素的作用.②本底ROI设置于肾脏正下方(20～160)象素大小、(0～16)象素距离范围内可减少本底大小、距离对GFR影响.     

A Dosimetric Comparative Analysis of TomoDirect and Three-Dimensional Conformal Radiotherapy in Early Breast Cancer

Purpose

The purpose of this study is to compare dosimetric parameters of intensity-modulated mode of TomoDirect and three-dimensional conformal radiotherapy (3D-CRT) in patients with early breast cancer.

Methods

TomoDirect and 3D-CRT planning were carried out for 26 patients with early breast cancer who had received breast-conserving surgery. A total of 50.4 Gy in 28 fractions were prescribed to the planning target volume. The organs at risk (OAR) such as lung and heart were contoured. Planning target volume (PTV) dose coverage, radiation conformity index (RCI), radical dose homogeneity index (rDHI), and irradiation dose of organs at risk were compared between TomoDirect and 3D-CRT planning.

Results

The mean PTV dose (51.65±0.37 Gy) and V_47.8 (100%) in TomoDirect were significantly higher than the mean PTV dose (50.88±0.65 Gy) and V_47.8 (89.23%±0.06%) in 3D-CRT (all, p<0.001). The RCI value in TomoDirect was significantly better than that in 3D-CRT (1.00 vs. 1.13, p<0.001). However, the rDHI value in TomoDirect was not significantly better than that in 3D-CRT (0.72 vs. 0.67, p=0.056). The mean lung dose and V₁₀, V₂₀, V₃₀, and V₄₀ values of ipsilateral lung in TomoDirect were significantly lower than those in 3D-CRT (all, p<0.05). There is no significant difference in the V₁₀, V₂₀, V₃₀, and V₄₀ values of heart between TomoDirect and 3D-CRT. And the mean dose for heart in TomoDirect was marginally lower than that in 3D-CRT (1.05 Gy vs. 1.62 Gy, p=0.085). The mean dose for left anterior descending coronary artery in left breast cancer was significantly lower in TomoDirect than in 3D-CRT (7.2 Gy vs. 12.1 Gy, p<0.001).

Conclusion

Compared to 3D-CRT, TomoDirect could result in favorable target coverage while reducing the irradiation dose of the ipsilateral lung for patients with early breast cancer.     

线圈填充因数与信噪比的关系

目的 分析线圈大小、样品体积对线圈信噪比的影响。方法 在体线圈中，使用1个大球形水模和1个小球形水模，水模置于线圈中央；在头、体及四肢线圈中，使用小球形水模，水模置于线圈中央。选用信噪比测量序列，每次扫描参数相同，检测信噪比。结果 体线圈中小球形水模图像信噪比较大球形水模图像信噪比高出4．0％，差异有统计学意义（P〈0．01）；体、头及四肢线圈的直径顺序变小，信噪比明显增大，但不呈简单的线性关系。结论 对于同一线圈，样本体积越小，填充因数越小，信噪比越好；对于同一样品，线圈的半径越小，填充因数越大，信噪比越好。     

肺小血管分支特征的CT测量研究

目的 利用影像学手段采用分支几何学方法探索在活体状态下肺小血管的分支特征。方法 通过对63例正常胸部螺旋CT扫描图像，采用分支几何学方法对2008套肺血管两分支状血管分支点两侧的血管横径进行测量，计算扩张因子和不对称因子，分析其特征及与母支直径的相关关系。结果 活体状态下两因子与标本数据存在差异；扩张因子均值为1．0022，不对称因子中位数为1．4938，分别与母支横径呈线性负、正相关，这一趋势在母支横径小于4．0mm时最为明显。母支横径大于6．0mm时，不对称因子分布趋势不明显。母支横径为2．5mm时，扩张因子迅速降至1．622，而不对称因子降至1．500左右。结论 用分支几何学方法研究肺小血管的分支特征，对认识肺血管的分支形态特点，建立血流和压力的数学及物理模型有潜在理论和实用价值。     

北京同步辐射装置(BSRF)医学成像实验研究

目的 探讨同步辐射技术用于医学成像的应用价值。方法 利用同步辐射光源的空间相干性、准直性、高亮度等特性进行成像实验。在北京同步辐射装置（BSRF）的4W1A束线上，使用衍射增强技术（DEI）对肝、肾等组织进行成像，部分结果与病理结果进行对照；使用白光技术对大鼠冠状动脉进行成像。2种技术的分辨率通过显微放大法获得。结果 成像结果均具有较高的衬度和分辨率，显微放大法获得的分辨率为微米量级。通过白光技术获得的大鼠心脏冠状动脉图像可显示到二级分支结构，部分可达三级结构。结论 DEI和白光技术等同步辐射成像技术可显示弱吸收组织及血管等微细结构，具有较好的应用前景。     

Infra-red surface thermography. Evaluation of a new radiometry instrument for measuring skin temperature over joints

Summary A study is reported of the evaluation of a new portable, light-weight, infrared thermometer, for the measurement of the skin temperature over joints. A high degree of reproducibility was observed, but no increase in heat was found over selected rheumatoid joints. The instrument wilt prove useful in detecting temperature changes in disease states where the changes are considerable, and where the ambient temperature can be strictly controlled.On sabbatical leave from McMaster University, Hamilton, Ontario, Canada.     

Prevention of experimental allergic encephalitis with in vivo administration of anti I-A antibody : Decreased accumulation of radiolabelled lymph node cells in the central nervous system

Experimental allergic encephalitis (EAE) can be prevented with the in vivo administration of monoclonal anti I-A antibody. A radiometric assay was developed to measure the accumulation of lymphocytes in the central nervous system of EAE animals. A direct correlation was observed between severity of clinical disease and the amount of radiolabelled lymph node cells (LNC) in the central nervous system. Injection of anti I-A antibody in vivo prevented clinical EAE and decreased the accumulation of radiolabelled LNC in spinal cord after immunization with mouse spinal cord homogenate and adjuvants.     

南京地区国人股骨头头颈直径比例的影像学测量

目的 通过X线片确定南京地区国人股骨头头颈直径比例的正常值.方法 选择468例无髋部症状的生活在南京及周边地区的成年中国人,男313名,女155名;年龄17～82岁,其中≤20岁13名,21～30岁88名,31～40岁123名,41～50岁104名,51～60岁102名,61～70岁24名,≥71岁14名,平均年龄42.4岁.摄标准骨盆正位X线片,应用Digimizer软件测量左、右侧股骨头最大直径与股骨颈最小纵径,并分别计算比值.将计算结果与西方人数据进行比较.结果 股骨头头颈直径比例1.33～1.69,平均1.48±0.09.≤20岁者1.46±0.09,21～30岁者1.48±0.09,31～40岁者1.47±0.10,41～50岁者1.46±0.09,51～60岁者1.49±0.10,61～70岁者1.48±0.08,≥71岁者1.49±0.10.不同性别、侧别及年龄组间差异均无统计学意义.南京地区国人股骨头头颈直径比例(左侧、右侧分别为1.48±0.09、1.48±0.10)与欧洲人数据(左侧、右侧分别为1.43±0.09、1.44±0.09)比较差异有统计学意义(P值均＜0.05).结论 南京地区国人股骨头头颈直径比例不存在性别、年龄及侧别差异.国人数据与欧洲人不同与种族的解剖差异有关.正常人群的股骨头头颈直径比例可能对某些髋关节疾病的诊断与治疗具有一定的参考意义.

Abstract：

Objective To measure the femoral head-neck ratio among Chinese adults in Nanjing to explore its clinical significance. Methods 468 Chinese without hip symptoms were chosen randomly. There were 313 males and 155 females. 13 cases were less than 20 years old, 88 cases were from 21 to 30 years old, 123 cases were from 31 to 40 years old, 104 cases were from 41 to 50 years old, 102 cases were from 51 to 60 years old, 24 cases were from 61 to 70 years old, 14 cases were more than 71 years old. The mean age was 42.4 years old (ranged from 17 to 82 years old). The maximum diameter of the femoral head and the minimum vertical diameter of femoral neck length on both sides were measured by Digimizer software in the standard anteroposterior pelvis film. The femoral head-neck ratio (FHNR) was calculated and compared with that of the western. Results The normal FHNR of Chinese in Nanjing was 1.48 ± 0.09 (1.33-1.69). FHNR was 1.46±0.09 in Chinese aged less than 20 years old. It was 1.48±0.09 in Chinese aged from 21 to 30 years, and 1.47±0.10 in those aged 31-40 years, 1.46±0.09 in 41-50 years, 1.49±0.10 in 51-60 years,1.48±0.08 in 61-70 years, 1.49±0.10 in those more than 71 years. There was no difference between male and female, the left and right side or the different age groups. There was no difference between the western and Chinese in Nanjing. Conclusion FHNR measurement has not variation with regard to sex, age and side. It may be useful to understand some kind of the hip diseases.     

肿瘤放疗中剂量测量用热释光探测器的基本特性研究

目的研究肿瘤放疗剂量测量用热释光探测器(TLD)的基本特性,为临床照射剂量测量提供可靠依据。方法应用TLD、NE-Farmer2581-A电离室剂量仪,热释光剂量读出系统,AECL-780C钴-60治疗机,用线性相关、t检验统计分析,了解剂量测量用TLD的质量、敏感度、剂量响应性、剂量重复性。结果 TLD表面洁净、光滑,直径、厚度分别为3.00、0.80mm,精度为±0.01%,面积重量为(29.4±0.9)mg/cm2,敏感度因子(Si)为1.00±0.09,在1 000cGy范围内读出发光值与辐射剂量呈线性关系,r值为0.99,在cGy剂量级重复使用10次,读出值变化0.66%。结论 TLD质量好、性能稳定、线性相关性强、重复测量精度高,符合国际推荐标准,可用于肿瘤放疗剂量测定。     

MRI 硬膜囊区域划分测量和中央型腰椎管狭窄症临床相关性分析

目的：采用区域划分法将腰椎MRI中硬膜囊划分为三个区域,测量其面积,且评估与中央型腰椎管狭窄症（LSCS）的临床相关性。方法本项目共有LSCS病例资料126例,自愿完成VAS、ODI问卷和行走距离调查,且行腰椎MRI检查,T2WI横断面影像中,测量整个硬膜囊的面积,然后将硬膜囊分为左、中、右三个区域,分别测量这三个区域的面积。组间和组内差异用方差分析,所有影像学测量数据和患者基本资料用Spearman检验（rs值表示）,和VAS、ODI、行走距离关系用Pearson检验（r值表示）,P＜0.05有统计学意义,rs值和r值绝对值越接近1,关联性越强。结果所有测量数据的组间和组内均无差异（P＞0.05）,整个硬膜囊面积、硬膜囊中间部分面积与VAS、ODI评分均无意义（P＞0.05）,左侧硬膜囊的面积与腰疼VAS评分（r＝-0.397）、ODI评分（r＝-0.404）有一定的关联（P＜0.05）,右侧硬膜囊面积和腰疼VAS评分（r＝-0.422）、腿疼VAS评分（r＝-0.392）、ODI评分（r＝-0.423）、行走距离（r＝-0.393）均有一定的关联（P＜0.05）,当左右两侧硬膜囊面积在0～25 mm2区间,和 ODI联系变得更加紧密（r＝-0.621,-0.625;P＜0.05）。结论区域划分测量法可以提高影像学和LSCS临床关联性,腰椎MRI中整个硬膜囊面积无明显LSCS临床相关性,硬膜囊左右两侧区域和LSCS临床之间有紧密联系。