髋关节功能位数字化断层融合成像观察髋关节撞击综合征相关征象的价值

目的 探讨髋关节屈曲外展外旋功能位下行数字化断层融合(DTS)成像观察髋关节撞击综合征(FAI)相关征象的价值.方法 对临床症状、体征、数字X线摄影(DR)前后位平片表现均符合FAI诊断的42例患者在髋关节屈曲外展外旋功能位下行DTS检查,以配对四格表x2检验比较DR前后位和DTS功能位对FAI各个相关征象检出的差异.结果 DTS功能位对股骨颈疝窝、股骨头颈交界处骨质突起、髋臼盂唇骨化、髋臼囊变4个征象的检出率(24％、43％、22％、19％)高于DR前后位(13％、22％、7％、6％)(二项分布确切概率法P=0.031、0.001、0.008、0.016);两种检查方法对髋臼骨赘、深髋臼、关节间隙狭窄、后壁征的检出差异没有统计学意义(DTS:72％、57％、11％、13％,DR:67％、57％、11％、13％,二项分布确切概率法P=0.25、1、1、1).结论 髋关节屈曲外展外旋功能位下行DTS可细致地观察撞击试验阳性患者髋关节的解剖结构异常及继发性骨质改变,并对相关征象进行精确定位.     

数字化断层融合技术在肺结节筛查中的临床应用研究

目的比较常规数字X线摄影(DR)与数字化断层融合技术(DTS)对肺部结节的检出率。资料与方法搜集本院同时行DR和DTS检查,并经CT证实的肺部结节患者83例共125个病灶作为研究对象,以CT证实的肺结节数目作为相对金标准,按结节大小分为3组(0.5≤D<1.0 cm,1.0≤D<2.0 cm,2.0≤D≤3.0 cm),由3位高年资放射科医师独立阅片,分别观察三组之间在DR与DTS上对相应部位肺结节的检出率,并对结果进行χ2检验。结果结节直径在0.5≤D<1.0 cm及1.0≤D<2.0 cm范围内,肺结节显示率DTS优于DR,且二者之间的差异具有统计学意义(P<0.05);结节直径在2.0≤D≤3.0 cm范围内,DTS与DR对肺结节显示率相近,二者之间的差异不具有统计学意义。结论 DTS排除解剖结构重叠的干扰,提高对病变检出的敏感性,可作为DR及CT在肺部结节筛查工作中的补充检查手段及患者胸部较小结节病灶的主要随访观察手段,甚至是作为高危人群肺结节筛查的主要检查方法。     

低剂量摄影在骨盆数字化X线摄影的应用

目的探讨低剂量摄影在使用自动曝光控制技术(automatic exposure control,AEC)的骨盆数字化X线摄影中的应用价值。资料与方法在对50例骨盆外伤患者初诊和复查时,分别以低剂量和常规剂量摄取骨盆前后位片,获得低剂量组和常规组各50幅图像,并对其曝光量和剂量面积值(dose area product,DAP)进行比较。图像按欧共体标准,由高年资医师与技师各一名观察并评级,对其结果进行统计学分析。结果低剂量组的曝光量值(2.48±1.20)显著低于常规组(14.78±1.20)(t=13.69,P<0.01)。同样,低剂量组的DAP(3.63±1.79)亦显著低于常规组(10.23±1.69)(t=9.22,P<0.01)。两组图像质量差异无统计学意义(Manne-Whitney U=1175.00,P=0.34)。结论低剂量骨盆摄影可大大降低曝光量和吸收剂量,而对图像质量无影响。     

应用数字化断层融合技术诊断足骨骨折的价值

目的：探讨X线数字化断层融合成像（DTS）在诊断足骨骨折中的价值。方法：搜集经临床证实的71例足骨骨折患者的病例资料,所有患者均行数字化X线摄影（DR）、DTS（Volume RAD技术）和CT检查。根据骨折是否累及关节,将患者分为骨折通过关节面组（A组）和骨折未通过关节面组（B组）。根据CT结果,对DR和DTS对两组患者的诊断结果进行比较,并对所有患者的DR和Volume RAD图像质量进行评估（2级评分法）。结果：A组中Volume RAD的诊断符合率（84．21％）高于DR（68．42％）,差异有统计学意义（P＜0．05）;B组中DR 和Volume RAD诊断结果的差异无统计学意义（P＞0．05）。71例患者Volume RAD优质图像的构成比（52／71）高于DR（64／71）。结论：X线数字化断层融合成像较DR能够更准确地显示通过关节面的足骨骨折,具有更好的图像质量,是临床诊断足骨骨折的良好辅助检查方法。     

数字化断层融合(DBT)与全视野数字X线摄影(FFDM)引导乳腺病灶定位对比

【摘要】目的:比较数字化断层融合（DBT）及全视野数字X线摄影（FFDM）引导乳腺病灶定位的异同。方法:回顾性搜集DBT引导乳腺病灶定位患者55例,FFDM引导定位患者65例。两种成像方式引导分别计算病灶中心三维坐标,通过乳腺定位针对病灶定位。当定位针针尖与病灶中心距离≤2cm时认为定位满意。应用独立样本t检验对两种方式定位满意率、定位时间、病灶穿刺时间及患者所接受辐射剂量进行比较。结果：DBT引导病灶定位满意率55/58,高于FFDM满意率67/73;定位时间对比上DBT要低于FFDM（609.14s vs 760.25s,P<0.05）;DBT病灶穿刺时间294.09s,低于FFDM 482.58s（P<0.05）;患者DBT引导比FFDM接受更少辐射剂量（9.13 vs 13.67mGy,P<0.05）。两种成像方式对恶性病灶定位满意率均高于良性病灶（DBT：26/27 vs 29/31;FFDM：26/27 vs 41/46）。而恶性病灶定位时间、穿刺时间则低于良性病灶。结论：相比于FFDM引导乳腺病灶定位,DBT能提供准确病灶深度信息,病灶定位满意率更高、定位时间及辐射剂量更少。     

幼儿髋关节的冠状断层解剖与MRI对照研究

目的:为幼儿髋关节病变的断层影像解剖和外科治疗提共实用的形态学依据.方法:在20例幼儿髋关节冠状断层标本,10例幼儿髋关节磁共振冠状图像上,研究了冠状断层幼儿髋关节的解剖结构.结果:在幼儿髋关节冠状断面上可清楚显示髋臼软骨、髋臼盂唇、骺板等重要结构;髋臼软骨在T1WI为带状中等信号,T2WI为中等信号,髋臼盂唇在T1WI、T2WI为低信号.骨骺、骺板在T1WI为带状中等低信号,T2WI为均匀高信号.结论:MRI可清析显示幼儿髋关节的解剖结构,在幼儿的外科疾病的诊断中应列为常规检查.     

数字合成体层成像低剂量特性在骨骼系统影像学中的研究

目的 对比数字化断层融合技术(DTS)与数字X射线摄影(DR)、电子计算机X射线断层扫描技术(CT)在骨骼系统影像学诊断中X射线辐射剂量的差异,分析3种检查方法在骨骼系统影像学诊断中的敏感性、特异性.方法 回顾性分析2010年2月至2012年3月间在本院同时行DR、DTS、CT骨骼系统检查的100名患者资料,对比DR、DTS、CT之间的X射线辐射剂量,以临床诊断结果为金标准,由2名专家评价3种检查方法的图像,对评价结果进行受试者操作特性曲线(ROC)分析.结果 DR、DTS、CT组的吸收剂量与有效剂量平均值分别为[(1.9±1.8)mGy、(0.03±0.03) mSv)]、[(3.5±1.5)mGy、(0.05±0.02) mSv)]、[(397.7±106.0)mGy·cm、(5.60±1.50) mSv].3种检查方法的吸收剂量和有效剂量差异有统计学意义(F=1377、1377,P＜0.05).采用LSD检验分析CT与DR、DTS的辐射剂量,差异有统计学意义(P＜0.05).阅片者A、B对DR、DTS、CT检出病灶可信度评价的ROC曲线下面积分别为0.870±0.035、0.966±0.018、0.974±0.015和0.852±0.038、0.951±0.021、0.959±0.019,对其进行Z检验,DR与DTS的差异有统计学意义(P＜0.05);DR与CT的差异有统计学意义(P＜0.05).CT与DR敏感性差异有统计学意义(x2 =4.833,P＜0.05).结论 DTS的辐射剂量只有CT的1％左右,其在骨骼系统的图像质量可以与CT相当.如有DR检查诊断不明确或有疑似病变的患者,推荐首选DTS进一步检查,减少不必要的辐射剂量.     

数字化断层融合对肺内小结节检出价值的ROC曲线评价

目的 探讨数字化断层融合(DTS)在肺内小结节检出中的应用价值.方法 43例经MSCT证实肺内小结节与43例经MSCT证实无肺内小结节患者均行后前位DR与DTS检查,由4位影像学诊断医师采用5级法分别对后前位DR与DTS图像上结节的有无进行评分并记录,以MSCT图像作为参照标准,对后前位DR与DTS的检出结果进行ROC曲线评价.结果 后前位DR与DTS检出肺内小结节的ROC曲线下的面积(Az)分别 为0.763±0.247(0.755、0.768、0.735、0.794)与0.941±0.209(0.946、0.910、0.951、0.956),2种检查方法的差异具有统计学意义( t=10.954,P=0.02,P<0.05).4位阅片医师对肺部小结节检出诊断一致性分析Kappa值均＞0.75,诊断一致性较好.结论 DTS对肺内小结节的检出明显优于后前位DR,具有较高的应用价值,可作为疑有肺内小结节患者的常规检查方法.     

迭代重建在膝关节置换术后X线数字化断层融合检查中的应用价值

目的：探讨 X 线数字化断层融合（DTS）运用迭代重建技术（IR）,降低膝关节图像金属植入物伪影的可行性和临床应用价值。方法：79例人工膝关节置换术后患者行 DTS 扫描,分别采用滤波反投影重建（FBP）技术和迭代重建（IR）技术对原始图像进行重建。从图像清晰度、假体金属植入物与周围骨相连结构的显示度、金属伪影的多少等方面对两组图像进行分析并评价。根据骨科临床对人工膝关节的分区,在后处理工作站上测量 A1～A7区域内假体与骨之间硬化束金属伪影的长度。结果：对两种重建技术所得到的图像进行主观评价,IR 组优片率为88．6％,FBP 组优片率为62％, IR 组优片率高于 FBP 组,差异有统计学意义（P ＜0．05）。IR 组重建图像在 A1、A3～A7区域无金属伪影,仅3例图像 A2区域见少许金属伪影,A7区域关节间隙内聚氨酸脂软垫显示清晰;FBP 组人工假体在 A1～A7区域均见金属伪影,伪影长度为0．5～2．6 mm。FBP 组图像伪影明显多于 IR 组。结论：有金属植入物的人工膝关节置换术后患者行 DTS 检查,运用 IR 技术可明显减少金属植入物伪影,图像质量明显改善,在术后随访中具有较高的临床应用价值。     

Simultaneous measurement of patient dose and distribution of indoor scattered radiation during digital breast tomosynthesis

Introduction

Breast cancer incidence increases from the age of 30 years. As this age range coincides with that in which women usually pursue pregnancy, undergoing medical examinations for conditions such as breast cancer is a concern, especially when pregnancy is uncertain during the first eight weeks. Moreover, in this age range, breast often exhibits a high density, thus compromising diagnosis. For such density, digital breast tomosynthesis (DBT) provides a more accurate diagnosis than 2D mammography given its higher sensitivity and specificity. However, radiation exposure increases during DBT, and it should be determined.

The effect of different exposure parameters on radiation dose in digital mammography and digital breast tomosynthesis: A phantom study

IntroductionThere are concerns regarding the increase in radiation dose among women undergoing both digital mammography (DM) and digital breast tomosynthesis (DBT). The aim of this study was to evaluate the effect of different exposure parameters on entrance skin dose (ESD) and average glandular dose (AGD) for DM and DBT using a phantom.MethodsThe ESD and AGD of 30 DM and DBT (cranio-caudal projection) examinations using a tissue equivalent phantom where acquired using a GE Senographe Essential DM unit. Commercial phantoms were used to simulate three different breast thicknesses and compositions. Tube potential, tube load, and target/filter combinations were also varied with ESD and AGD recorded directly from the DM unit. Comparisons were made using the non-parametric Kruskal Wallis, Mann–Whitney, and Wilcoxon signed rank tests.ResultsThe individual ESD values for 4 cm, 5 cm, and 6 cm thick phantoms for DM and DBT at Rh/Rh target/filter combination and 30–32 kV/56 mAs levels were 5.06 and 4.18 mGy; 5.82 and 5.08 mGy; and 7.26 and 11.4 mGy, respectively; while AGDs were 1.57 and 1.30 mGy, 1.33 and 1.39 mGy; and 1.29 and 3.60 mGy, respectively. The Kruskal–Wallis test showed a statistically significant difference in AGD for DM (P = .029) but not for DBT (P = 0.368). The Mann–Whitney and Wilcoxon signed rank tests showed no statistically significant difference for ESD or AGD between both DM and DBT techniques (P = .827 and .513). The percentage differences in ESD for phantom thicknesses of 4 cm, 5 cm, and 6 cm between DBT and DM ranged between −21% and 36%; while for AGD between −21% and 64.2%.ConclusionsThe ESD and AGD for single view projection in DM and DBT showed differences at 4 and 6 cm breast thicknesses and compositions but not at 5 cm thickness with 30–32 kV and a Rh/Rh target/filter combination.Implications for practiceA fibro-fatty breast results in less radiation dose variations in terms of ESD and AGD between DM and DBT techniques.     

全视野数字乳腺摄影结合乳腺数字体层合成摄影的辐射剂量与压迫厚度及乳房密度的相关性研究

目的 对比分析乳腺数字体层摄影及全数字乳腺摄影（DBT/FFDM）模式平均腺体剂量（AGD）与乳房密度、压迫厚度的关系,探讨不同类型（厚度和密度）乳房在具体情况下摄影方式的优化选择与应用。方法 回顾性分析229例乳房Combo （DBT+FFDM）临床资料,分别收集记录双乳正位（CC）及内外斜位（MLO）压迫厚度、AGD、kVp和乳房量化密度（Q_abd）类型,分析DBT/FFDM模式下压迫厚度、密度与AGD之间的关系。结果 DBT/FFDM模式AGD与压迫厚度（CC位：r=0.55、0.53,P<0.001;MLO位：r=0.62、0.48,P<0.001）、乳房密度（CC位：r=0.36、0.39,P<0.001;MLO位：r=0.16、0.30,P<0.001）正相关;DBT模式AGD组间差异小,FFDM模式AGD组间差异大（厚度分组CC位：F=35.29、31.32,P<0.005;MLO位：F=44.83、27.02,P<0.005;Q_abd分类CC位：F=18.68、19.76,P<0.005;MLO位：F=4.58、10.52,P<0.005）;Q_abd分类高的乳房平均压迫厚度较低（CC位：F=16.28,P<0.005;MLO位：F=17.81,P<0.005）;同时考虑压迫厚度与乳房密度交互作用影响,仅在MLO位DM模式对AGD有交互作用（F=3.16,P=0.005）。结论 DBT/FFDM两种模式剂量累积可能增加辐射风险;乳腺摄影优先采用单视图CC/MLO-DBT或CC/MLO-（DBT+FFDM）+单视图MLO/CC-FFDM模式,在减低辐射剂量风险方面有积极作用。     

Comparative study of DTS and CT in the skeletal trauma imaging diagnosis evaluation and radiation dose

Purpose

To compare the differences between CT (Computed tomography) and DTS (digital tomosynthesis) in the X-ray radiation dose, and to analyze the sensitivity and specificity of each examination to check the suspected fractures and dislocations cases.

Methods

From May 2010 to February 2012, 46 patients suspected with fractures and/or dislocations were prospectively enrolled to do the CT and DTS examination on the basis of the results of DR examination. Patients were considered ineligible if they were pregnant or lactating (female subjects only). The Yangzhou Regional Ethical Review Board in Jiangsu province, China approved this study. All 46 patients signed the informed consent. To contrast radiation dose between CT and DTS group of the patients and make statistical analysis. Two experienced experts assess the image quality by I–III grade and make statistical analysis. Draw the ROC of reader A and B according to the golden standard of clinical diagnosis.

Results

The average effective dose of CT Group is 5.46 msv, while average effective dose of DTS group is 0.07 msv.There is significant statistical difference (t = 22.89, p < 0.01) between them. Calculate and compare the area under the ROC curve of reader A and B. The area of reader A by CT and DTS is 0.999 ± 0.005, 0.973 ± 0.022. The area of reader B is 0.961 ± 0.026, 0.944 ± 0.032. Both of them perform z test, and P > 0.05. There is no significant difference. Assess the uniformity of two readers with Kappa test. The Kappa value of reader A and B is respectively 0.757 and 0.783. When the value is greater than 0.75, two readers’ uniformity is considered well. The two readers’ sensitivity and specificity in diagnosing hidden skeletal trauma with CT and DTS are respectively 97.06% (reader A), 96.97% (reader B); 91.67% (reader A), 84.62% (reader B). Use the χ² test to them, then get the same result: P > 0.05. There is no statistical significant.

Conclusion

Radiation dose of VolumnRAD DTS only account for 1.5% of CT, but its image can meet the requirements for clinical diagnosis. When fracture and/or dislocation is suspected with DR, VolumnRAD DTS can be recommended firstly as further checks.     

Breast tomosynthesis: A diagnostic addition to screening digital mammography

Objectives

Comparison between digital mammography alone and with adding digital breast tomosynthesis in breast cancer screening.

Radiation dose of digital tomosynthesis for sinonasal examination: comparison with multi-detector CT

Objective

Using an anthropomorphic phantom, we have investigated the feasibility of digital tomosynthesis (DT) of flat-panel detector (FPD) radiography to reduce radiation dose for sinonasal examination compared to multi-detector computed tomography (MDCT).

Materials and methods

A female Rando phantom was scanned covering frontal to maxillary sinus using the clinically routine protocol by both 64-detector CT (120 kV, 200 mA s, and 1.375-pitch) and DT radiography (80 kV, 1.0 mA s per projection, 60 projections, 40° sweep, and posterior–anterior projections). Glass dosimeters were used to measure the radiation dose to internal organs including the thyroid gland, brain, submandibular gland, and the surface dose at various sites including the eyes during those scans. We compared the radiation dose to those anatomies between both modalities.

Results

In DT radiography, the doses of the thyroid gland, brain, submandibular gland, skin, and eyes were 230 ± 90 μGy, 1770 ± 560 μGy, 1400 ± 80 μGy, 1160 ± 2100 μGy, and 112 ± 6 μGy, respectively. These doses were reduced to approximately 1/5, 1/8, 1/12, 1/17, and 1/290 of the respective MDCT dose.

Conclusion

For sinonasal examinations, DT radiography enables dramatic reduction in radiation exposure and dose to the head and neck region, particularly to the lens of the eye.     

数字摄影受检者辐射剂量调查

目的 了解数字摄影（DR）检查中受检者的辐射剂量水平,为数字放射摄影受检者指导水平的制定提供基础数据。方法 使用热释光剂量计TLD测量受检者不同部位、不同投照方向的入射体表剂量（ESD）;使用剂量面积乘积仪测量受检者不同部位、不同投照方向的剂量面积乘积（DAP）,并利用测量的DAP值,估算出有效剂量（E）。结果 同类检查中,kV和mAs的变化范围较大,不同部位DR检查中ESD、DAP和E的差别均具有统计学意义（F=33.47、24.68、43.19,P<0.05）。其中,ESD和DAP均以腰椎（LAT）最高,均数为4.62mGy/次和2.26Gy·cm²/次;E以腹部（AP）最高,均数为0.59mSv,高于腰椎（LAT）的0.31mSv。结论 DR在加强受检者放射防护最优化方面很有潜力,应尽快建立适合我国国民体质特征的数字放射摄影受检者辐射剂量的指导水平。     

Breast cancer detection: Comparison of digital mammography and digital breast tomosynthesis across non-dense and dense breasts

IntroductionBreast density is associated with an increase in breast cancer risk and limits early detection of the disease. This study assesses the diagnostic performance of mammogram readers in digital mammography (DM) and digital breast tomosynthesis (DBT).MethodsEleven breast readers with 1–39 years of experience reading mammograms and 0–4 years of experience reading DBT participated in the study. All readers independently interpreted 60 DM cases (40 normal/20 abnormal) and 35 DBT cases (20 normal/15 abnormal). Sensitivity, specificity, ROC AUC, and diagnostic confidence were calculated and compared between DM and DBT.ResultsDBT significantly improved diagnostic confidence in both dense breasts (p = 0.03) and non-dense breasts (p = 0.003) but not in other diagnostic performance metrics. Specificity was higher in DM for readers with >7 years' experience (p = 0.03) in reading mammography, non-radiologists (p = 0.04), readers who had completed a 3–6 months training fellowship in breast imaging (p = 0.04), and those with ≤2 years’ experience in reading DBT (p = 0.02), particularly in non-dense breasts.ConclusionDiagnostic confidence was higher in DBT when compared to DM. In contrast, other performance metrics appeared to be similar or better with DM and may be influenced by the lack of experience of the reader cohort in reading DBT.Implications for practiceThe benefits of DBT may not be entirely accrued until radiologists attain expertise in DBT interpretation. Specificity of DBT varied according to reader characteristics, and these characteristics may be useful for optimising pairing strategies in independent double reading of DBT as practiced in Australia to reduce false positive diagnostic errors.