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1.
目的:探讨MR弥散加权成像(DWI)鉴别诊断良恶性椎体压缩性骨折的临床价值。方法:对57 例经临床或病理证实的椎体 良恶性压缩性骨折患者行矢状位T1WI、T2WI、T2WI/FS 及DWI扫描,研究其在常规序列和DWI序列上的表现,将常规MR 序列 和DWI序列检出率进行比较,测量正常椎体及病变椎体的表观弥散系数(ADC)值,并进行统计学分析。结果:(1)MR 常规序列和 DWI序列(b=500s/mm2)表现:良性椎体压缩性骨折呈长T1 长或等T2 改变,T2WI/FS 呈高信号,DWI 可以呈高信号、等信号及低 信号;恶性椎体压缩性骨折呈长T1 长T2 信号,大部分病灶T2WI/FS 及DWI呈高信号,少数变现为低信号;(2)MR 常规序列和 DWI 序列(b=500s/mm2)病灶检出率的比较:T1WI、T2WI/FS 及DWI序列病灶检出率均高于T2WI 序列,其间的差别有显著性意 义(P<0.01),T1WI、T2WI/FS 及DWI序列病灶检出率之间无显著性差异(P>0.01);(3)ADC 值比较:在DWI(b=500 s/mm2)上,良性组 ADC 值为(2.03± 0.83)× 10-3mm2/s,恶性组ADC 值为(1.37 ± 0.75)× 10-3mm2/s,正常组ADC值为(0.36± 0.21)× 10-3mm2/s,成像条 件相同时,良性组高于恶性组,两组间有明显的统计学意义(P<0.05)。结论:DWI可较好的反映椎体的弥散特征,ADC值作为量化 指标可对良恶性椎体压缩性骨折进行可靠鉴别。  相似文献   

2.
目的:探讨MR弥散加权成像(DWI)鉴别诊断良恶性椎体压缩性骨折的临床价值。方法:对57例经临床或病理证实的椎体良恶性压缩性骨折患者行矢状位T1M、T2WI、T2WI/FS及DWI扫描,研究其在常规序列和DWI序列上的表现,将常规MR序列和DWI序列检出率进行比较,测量正常椎体及病变椎体的表观弥散系数(ADC)值,并进行统计学分析。结果:(1)MR常规序列和DWI序列(b=500s/mm2)表现:良性椎体压缩性骨折呈长T1长或等T2改变,T2WI/FS呈高信号,DWI可以呈高信号、等信号及低信号;恶性椎体压缩性骨折呈长T1长T2信号,大部分病灶T2WUFS及DWI呈高信号,少数变现为低信号;(2)MR常规序列和DWI序列(b=500s/mm2)病灶检出率的比较:T1WI、T2WI/FS及DWI序列病灶检出率均高于T2WI序列,其间的差别有显著性意义(P〈0.01),T1WI、T2WI/FS及DWI序列病灶检出率之间无显著性差异(P〉0.01);(3)ADC值比较:在DWI(b=500s/mm2)上,良性组ADC值为(2.03±0.83)×10^3mm^2/s,恶性组ADC值为(1.37±0.75)×10^-3mm^2/s,正常组ADC值为(0.36±0.21)×10^-3mm^2/s,成像条件相同时,良性组高于恶性组,两组间有明显的统计学意义(P〈0.05)。结论:DWI可较好的反映椎体的弥散特征,ADC值作为量化指标可对良恶性椎体压缩性骨折进行可靠鉴别。  相似文献   

3.
目的:探讨磁共振弥散加权成像(DWI)及表观扩散系数(ADC)值在鼻咽癌颅底放疗中的临床价值。方法:收集我院于2013年6月~2014年6月复查的40例鼻咽癌患者,分别于放疗前及放疗结束12个月以后对所有患者行常规核磁共振成像(MRI)及DWI检查,测量放疗前、后ADC值,根据影像学检查以及临床诊断结果分为复发组(n=5)及未复发组(n=35)。结果:复发组放疗前ADC值为(0.797±0.031)×10~(-3)mm~2/s,与未复发组放疗前ADC值(0.805±0.028)×10~(-3)mm~2/s比较,差异无统计学意义(P0.05)。复发组放疗结束12个月以后ADC值为(1.097±0.091)×10~(-3)mm~2/s,与未复发组放疗结束12个月以后ADC值(1.705±0.128)×10~(-3)mm~2/s比较,差异有统计学意义(P0.05)。结论:DWI作为一种新兴的磁共振成像技术,对于鼻咽癌颅底放疗疗效的评价具有重要价值,通过DWI对ADC值的测量,可有效的预测患者预后是否良好。  相似文献   

4.
目的:探讨磁共振成像(Magnetic resonance imaging,MRI)对非小细胞肺癌的诊断价值。方法:选择2016年9月-2019年4月南京医科大学附属脑科医院(胸科院区)放射科收治的肺部结节患者74例,包括病理证实为肺部良性病变54例(良性组)和非小细胞肺癌20例(肺癌组)。所有患者都给予常规MRI、增强MRI与磁共振扩散加权成像(Diffusion weighted imaging,DWI),记录影像学特征并评估其诊断价值。结果:肺癌组的病灶形态、边缘等MRI特征与良性组对比差异无统计学意义(P0.05)。在b值=0、600、800、1000 s/mm~2条件下,肺癌组的病灶表观扩散系数(Apparent diffusion coefficient,ADC)值都显著低于良性组(P0.05)。肺癌组的病灶MRI增强Ⅰ型+Ⅱ型比例显著高于良性组(P0.05)。MRI鉴别诊断非小细胞肺癌的敏感性与特异性为98.1%和94.4%。结论:MRI用于非小细胞肺癌的诊断能反映病灶组织的血流动力学与水分子活动状况,具有较高的诊断敏感性与特异性。  相似文献   

5.
摘要 目的:研究3.0 T磁共振扩散加权成像在乳腺良恶性病变鉴别中的价值及较优b值下ADC值与预后因子的相关性。方法:选取2017年11月~2019年11月于我院接受诊治的乳腺病变患者50例进行研究,将其按照良恶性差异分成恶性组40例与良性组10例,另取同期于我院体检的健康志愿者50例作为对照组。对所有人员均进行3.0 T磁共振扩散加权成像,比较不同b值下ADC值在不同乳腺组织中的差异,比较不同b值下诊断乳腺良恶性病变的效能,分析较优b值下ADC值和乳腺癌患者各项预后因子的相关性。结果:对照组、良性组、恶性组在不同b值下的ADC值均呈逐渐降低趋势(P<0.05);对照组、良性组、恶性组b值为1000 s/mm2下的ADC值均低于b值为600 s/mm2(P<0.05)。b值为1000 s/mm2时诊断乳腺恶性病变的敏感度、特异度、准确度分别为92.50%、100.00%、94.00%,高于b值为600 s/mm2的70.00%、60.00%、68.00%(P<0.05)。b值为1000 s/mm2下雌激素受体、孕激素受阳性患者的ADC值低于阴性患者,而人类表皮生长因子受体2阳性患者的ADC值高于阴性患者(P<0.05)。经Spearman相关性分析可得,b值为1000 s/mm2下ADC值与雌激素受体、孕激素受体阳性表达均呈负相关关系,而与人类表皮生长因子受体2阳性表达呈正相关关系(P<0.05)。结论:3.0 T磁共振扩散加权成像在乳腺良恶性病变鉴别中的价值较高,且以b值为1000 s/mm2的诊断能效较优。此外,b值下ADC值和乳腺癌部分预后因子表达状态密切相关。  相似文献   

6.
目的:探讨磁共振体素内不相干运动扩散加权成像(intravoxel incoherent motion diffusion weighted MR Imaging,IVIM-DWI)在肺癌所致肺不张的影像诊断中的初步应用。方法:选取独立肺段肺不张病变患者43例,其中肺癌致肺不张31例(肺癌组),局部炎症致肺不张12例(炎症组)。所有患者在药物治疗或手术前均行3.0T磁共振IVIM-DWI检查,b值取0、50、100、200、400、600、800、1000 s/mm~2,分别测量灌注分数(perfusion fraction,f)、真实扩散系数(diffusion coefficient,D)以及关注相关扩散系数(diffusion coefficient from the perfused compartment,D*),对上述参数值进行相关统计学分析,并依据受试者工作特征曲线(Receiver Operating Characteristic,ROC)对各参数的评价效能进行分析。结果:肺癌组的D值、D*值以及f值分别为(0.64±0.16)×10~(-3)mm~2/s、(19.77±6.16)×10~(-3)mm~2/s以及(29.62±9.74)%,而炎症组的D值、D*值以及f值分别为(0.67±0.14)×10~(-3) mm~2/s、(21.14±8.32)×10~(-3)mm~2/s以及(47.62±11.46)%;经比较,肺癌组D值、D*值与炎症组无统计学差异(P0.05),而二者f值差异显著,有统计学意义(P0.01)。f值最佳阈值为38.42%,此时曲线下面积(Area Under Curve,AUC)为0.94,诊断肺癌的特异度为0.89,敏感度为0.93,阳性预测值为0.92,阴性预测值为0.89。结论:磁共振IVIM-DWI技术在肺癌所致肺不张的影像诊断中具有一定的应用价值。  相似文献   

7.
目的:声触诊组织定量技术(VTQ)是一种新的弹性成像方法,能够定量、无创地评价组织硬度信息。本文的研究目的是探讨声触诊组织定量技术在鉴别诊断甲状腺微小癌(TMCs)中的应用价值。方法:应用VTQ技术对110例共114个结节(最大直径≤1 cm)进行检测,获取并分析结节及周边甲状腺组织的横向剪切波速度(SWV)。利用ROC曲线对测量结果进行分析,评价VTQ技术的诊断价值并确定最佳诊断界值。结果:114个结节中良性结节32个(30个为结节性甲状腺肿,2个为腺瘤),恶性结节82个(均为乳头状癌)。甲状腺良性结节及周边甲状腺组织的SWV平均值分别为(2.30±0.49)m/s、(2.08±0.40)m/s,恶性结节及周边甲状腺组织的SWV平均值分别为(3.12±0.97)m/s、(2.06±0.46)m/s。恶性结节的SWV值明显高于良性结节,两者之间差异具有统计学意义(t=5.911,P0.0001);恶性结节与其周边甲状腺组织比较有显著差异(P0.0001);而良性结节与其周边甲状腺组织无统计学差异(P0.05)。ROC曲线下面积为0.833,以2.30 m/s诊断界值点时,敏感度、特异度分别为90.2%、62.5%。结论:甲状腺恶性结节的SWV值明显高于良性结节。VTQ技术能够提供组织硬度信息,在鉴别诊断甲状腺微小癌方面具有一定的临床应用价值。  相似文献   

8.
目的:研究常规高频超声与超声弹性成像在甲状腺结节良恶性鉴别诊断中的应用价值。方法:选择住院的甲状腺结节性疾病患者120例(146个甲状腺结节)。对患者进行常规高频超声和超声弹性成像检查,以术后病理检查为金标准,计算不同方法对甲状腺良恶性结节鉴别诊断的灵敏度、特异度、准确度。结果:120例患者,经手术病理检查证实有146个结节,其中良性结节98个,恶性结节48个。常规高频超声显示在形态、边界、包膜、内部回声、微钙化及RI值上,甲状腺良、恶性结节之间的差异有统计学意义(P0.05)。常规高频超声与弹性成像相比,诊断效能之间的差异无统计学意义(P0.05);常规高频超声与联合超声诊断的灵敏度(X~2=12.22,P0.01)、特异度(X~2=10.21,P0.01)、准确度(X~2=9.31,P0.01)相比较,差异具有统计学显著性;超声弹性成像与联合超声诊断灵敏度(X~2=6.51,P0.01)、特异度(X~2=5.82,P0.05)、准确度(X~2=4.56,P0.05)相比,差异具有统计学显著性。结论:常规高频超声联合超声弹性成像对甲状腺良恶性结节的诊断灵敏度和准确度高,值得进一步推广临床应用。  相似文献   

9.
目的:声触诊组织定量技术(VTQ)是一种新的弹性成像方法,能够定量、无创地评价组织硬度信息。本文的研究目的是探讨声触诊组织定量技术在鉴别诊断甲状腺微小癌(TMCs)中的应用价值。方法:应用VTQ 技术对110 例共114 个结节(最大直径≤1 cm)进行检测,获取并分析结节及周边甲状腺组织的横向剪切波速度(SWV)。利用ROC曲线对测量结果进行分析,评价VTQ技术的诊断价值并确定最佳诊断界值。结果:114 个结节中良性结节32 个(30 个为结节性甲状腺肿,2 个为腺瘤),恶性结节82 个(均为乳头状癌)。甲状腺良性结节及周边甲状腺组织的SWV 平均值分别为(2.30± 0.49) m/s、(2.08± 0.40) m/s,恶性结节及周边甲状腺组织的SWV 平均值分别为(3.12± 0.97) m/s、(2.06± 0.46) m/s。恶性结节的SWV 值明显高于良性结节,两者之间差异具有统计学意义(t=5.911,P<0.0001);恶性结节与其周边甲状腺组织比较有显著差异(P<0.0001);而良性结节与其周边甲状腺组织无统计学差异(P>0.05)。ROC曲线下面积为0.833,以2.30 m/s诊断界值点时,敏感度、特异度分别为90.2%、62.5%。结论:甲状腺恶性结节的SWV 值明显高于良性结节。VTQ 技术能够提供组织硬度信息,在鉴别诊断甲状腺微小癌方面具有一定的临床应用价值。  相似文献   

10.
目的:探讨基于磁共振(Magnetic Resonance Imaging,MRI)多b值弥散加权成像(Diffusion Weighted Imaging,DWI)对严重胸外伤预后的预测价值。方法:2018年2月-2020年6月选择在本院诊治的严重胸外伤患者76例(开放性损伤38例,闭合性损伤38例),所有患者都给予常规MRI扫描、多b值DWI扫描,记录成像质量与特征,判断预测价值。结果:所有患者都在胸外伤后3 d内进行检查,开放性损伤与闭合性损伤患者的MRI图像质量优良率都为100.0%,符合诊断要求。开放性损伤患者的多b值DWI之D*值、f值都显著高于闭合性损伤患者,而D值显著低于闭合性损伤患者,对比差异都有统计学意义(P<0.05)。在76例患者中,病理判断为胸腔后方韧带复合体1级损伤38例,2级损伤30例,3级损伤8例。MRI诊断为1级损伤39例,2级损伤31例,3级损伤6例,MRI诊断的准确性为93.4%。结论:基于MRI多b值DWI能清晰显示严重胸外伤的组织损伤情况,也能真实反映组织的微环境变化特征,能有效预测后方韧带复合体的损伤情况。  相似文献   

11.
Rather than simply acting as a photographic camera capturing two‐dimensional (x, y) intensity images or a spectrometer acquiring spectra (λ), a hyperspectral imager measures entire three‐dimensional (x, y, λ) datacubes for multivariate analysis, providing structural, molecular, and functional information about biological cells or tissue with unprecedented detail. Such data also gives clinical insights for disease diagnosis and treatment. We summarize the principles underpinning this technology, highlight its practical implementation, and discuss its recent applications at microscopic to macroscopic scales.

Datacube acquisition strategies in hyperspectral imaging x, y, spatial coordinates; λ, wavelength.  相似文献   


12.
The main goals of this review is to provide an up-to-date account of the different uses of Cerenkov radiation (CR) and radioluminescence imaging for pre-clinical small animal imaging. We will focus on new emerging applications such as the use of Cerenkov imaging for monitoring radionuclide and external radiotherapy in humans. Another novel application that will be described is the monitoring of radiochemical synthesis using microfluidic chips.Several pre-clinical aspects of CR will be discussed such as the development of 3D reconstruction methods for Cerenkov images and the use of CR as excitation source for nanoparticles or for endoscopic imaging.We will also include a discussion on radioluminescence imaging that is a more general method than Cerenkov imaging for the detection using optical methods of alpha and gamma emitters.  相似文献   

13.
While metal ions play an important role in the proper functioning of all life, many questions remain unanswered about exactly how different metals contribute to health and disease. The development of fluorescent probes, which respond to metals, has allowed greater understanding of the cellular location, concentration and speciation of metals in living systems, giving a new appreciation of their function. While the focus of studies using these fluorescent tools has largely been on mammalian organisms, there has been relatively little application of these powerful tools to other organisms. In this review, we highlight recent examples of molecular fluorophores, which have been applied to sensing metals in non-mammalian organisms.  相似文献   

14.
Sub diffraction limited infrared absorption imaging of hemoglobin was performed by coupling IR optics with an atomic force microscope. Comparisons between the AFM topography and IR absorption images of micron sized hemoglobin features are presented, along with nanoscale IR spectroscopic analysis of the metalloprotein. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

15.
Molecular optoacoustic (photoacoustic) imaging typically relies on the spectral identification of absorption signatures from molecules of interest. To achieve this, two or more excitation wavelengths are employed to sequentially illuminate tissue. Due to depth‐related spectral dependencies and detection related effects, the multispectral optoacoustic tomography (MSOT) spectral unmixing problem presents a complex non‐linear inversion operation. So far, different studies have showcased the spectral capacity of optoacoustic imaging, without however relating the performance achieved to the number of wavelengths employed. Overall, the dependence of the sensitivity and accuracy of optoacoustic imaging as a function of the number of illumination wavelengths has not been so far comprehensively studied. In this paper we study the impact of the number of excitation wavelengths employed on the sensitivity and accuracy achieved by molecular optoacoustic tomography. We present a quantitative analysis, based on synthetic MSOT datasets and observe a trend of sensitivity increase for up to 20 wavelengths. Importantly we quantify this relation and demonstrate an up to an order of magnitude sensitivity increase of multi‐wavelength illumination vs. single or dual wavelength optoacoustic imaging. Examples from experimental animal studies are finally utilized to support the findings.

In vivo MSOT imaging of a mouse brain bearing a tumor that is expressing a near‐infrared fluorescent protein. ( a ) Monochromatic optoacoustic imaging at the peak excitation wavelength of the fluorescent protein. ( b ) Overlay of the detected bio‐distribution of the protein (red pseudocolor) on the monochromatic optoacoustic image. ( c ) Ex vivo validation by means of cryoslicing fluorescence imaging.  相似文献   


16.
A wearable scanning photoacoustic imaging (wPAI) system is presented for noninvasive brain study in behaving rats. This miniaturized wPAI system consists of four pico linear servos and a single transducer‐based PAI probe. It has a dimension of 50 mm × 35 mm × 40 mm, and a weight of 26 g excluding cablings. Phantom evaluation shows that wPAI achieves a lateral resolution of ~0.5 mm and an axial resolution of ~0.1 mm at a depth of up to 11 mm. Its imaging ability is also tested in a behaving rat, and the results indicate that wPAI is able to image blood vessels at a depth of up to 5 mm with intact scalp and skull. With its noninvasive, deep penetration, and functional imaging ability in behaving animals, wPAI can be used for behavior, cognition, and preclinical brain disease studies.

  相似文献   


17.
乳腺癌是危及女性健康的常见恶性肿瘤之一,病死率较高,且发病年龄呈年轻化趋势。目前临床对乳腺疾病的检查方法很多,既往检查主要包括钼靶、超声等,因价格便宜、操作方便,已成为常规的乳腺疾病检查方法,但两者的敏感性和特异性较低并有自身的局限性。CT软组织分辨率较高,但检查过程中的X线剂量较大,并且动态增强时间较长,故作为乳腺钼靶的补充检查手段。这些检查方法对乳腺疾病均有不同的诊断意义,在当前众多诊断乳腺疾病方法中,具有无辐射,较高软组织分辨力及可多方位多层面成像的乳腺磁共振(MRI)成像有其独到的优势,某些方面能弥补超声和钼靶检查的局限性,乳腺磁共振可提供病灶形态学和增强血流动力学表现,可用于常规检查方法不能确诊病灶的鉴别诊断。乳腺肿瘤MRI成像对临床诊断、鉴别诊断及手术方案的选择有着极其重要的作用。本文就乳腺MRI影像技术、MRI影像学表现及其临床应用予以综述,探讨MRI在乳腺肿瘤中的应用。  相似文献   

18.
This study characterizes the scatter‐specific tissue contrast that can be obtained by high spatial frequency (HSF) domain imaging and cross‐polarization (CP) imaging, using a standard color imaging system, and how combining them may be beneficial. Both HSF and CP approaches are known to modulate the sensitivity of epi‐illumination reflectance images between diffuse multiply scattered and superficially backscattered photons, providing enhanced contrast from microstructure and composition than what is achieved by standard wide‐field imaging. Measurements in tissue‐simulating optical phantoms show that CP imaging returns localized assessments of both scattering and absorption effects, while HSF has uniquely specific sensitivity to scatter‐only contrast, with a strong suppression of visible contrast from blood. The combination of CP and HSF imaging provided an expanded sensitivity to scatter compared with CP imaging, while rejecting specular reflections detected by HSF imaging. ex vivo imaging of an atlas of dissected rodent organs/tissues demonstrated the scatter‐based contrast achieved with HSF, CP and HSF‐CP imaging, with the white light spectral signal returned by each approach translated to a color image for intuitive encoding of scatter‐based contrast within images of tissue. The results suggest that visible CP‐HSF imaging could have the potential to aid diagnostic imaging of lesions in skin or mucosal tissues and organs, where just CP is currently the standard practice imaging modality.   相似文献   

19.
Multispectral and hyperspectral imaging (HSI) are emerging optical imaging techniques with the potential to transform the way surgery is performed but it is not clear whether current systems are capable of delivering real‐time tissue characterization and surgical guidance. We conducted a systematic review of surgical in vivo label‐free multispectral and HSI systems that have been assessed intraoperatively in adult patients, published over a 10‐year period to May 2018. We analysed 14 studies including 8 different HSI systems. Current in‐vivo HSI systems generate an intraoperative tissue oxygenation map or enable tumour detection. Intraoperative tissue oxygenation measurements may help to predict those patients at risk of postoperative complications and in‐vivo intraoperative tissue characterization may be performed with high specificity and sensitivity. All systems utilized a line‐scanning or wavelength‐scanning method but the spectral range and number of spectral bands employed varied significantly between studies and according to the system's clinical aim. The time to acquire a hyperspectral cube dataset ranged between 5 and 30 seconds. No safety concerns were reported in any studies. A small number of studies have demonstrated the capabilities of intraoperative in‐vivo label‐free HSI but further work is needed to fully integrate it into the current surgical workflow.   相似文献   

20.
IntroductionIn preclinical research, the growing number of transgenic models has led to the need for renal-function studies in mice. Many efforts have been made to develop dedicated SPECT systems for rodents, but their availability is limited due to high capital costs. The aim of this work is to demonstrate the feasibility of mouse renal imaging by using an inexpensive alternative based on clinical gamma-cameras.MethodsA healthy mouse was scanned 3 h after injection of 6 mCi of Dimercaptosuccinic acid (DMSA) labeled with 99mTc by using a single-head gamma-camera in conjunction with a dedicated pinhole collimator. List-mode data were binned to emulate multiple injections of 1 mCi, 0.1 mCi and 0.01 mCi of 99mTc-DMSA and 6-min ventral and dorsal planar images were acquired and SPECT imaging (60 projection images acquired over 60 min) was performed. An optimization of the protocols in terms of injected activity, time scan, renal cortex uniformity and cortex-to-pelvis contrast was carried out.ResultsThe appropriate protocols were an injected activity of 0.6 mCi, combined with duration of scanning of 1 min for planar and 60 min for SPECT imaging. Our results were validated through the relative quantification of renal function, which showed that both kidneys contributed equally to the total function. They showed that functional structures of the mouse kidneys can be visually distinguished as easily as in human studies.ConclusionsOur findings showed the feasibility of conducting quantitative DMSA SPECT studies of anesthetized mice on clinical gamma cameras.  相似文献   

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