16层CT多平面重建与最大密度投影诊断孤立性肺结节的应用价值

目的:探讨多层CT后处理技术对孤立性肺结节的诊断价值。方法:对符合条件的56例患者行CT扫描,原始采集层厚为0.75mm,重建层厚7mm。发现结节时利用层厚为0.75mm的原始数据对病灶及周围组织进行三维重建,MPR重建包括冠状位、矢状位和病灶最大径平面图像,应用后处理软件重建出最大密度投影图像。结果:56例肺结节中恶性结节31例,良性结25例。4例假阴性包括2例腺癌、1例鳞癌和1例小细胞癌,4例病灶直径均小于1.0cm。5例假阳性包括2例肌纤维母细胞瘤和3例结核球。三维率>1.5的肺结节89%是良性SPN。结论:多层CT多平面重建与最大密度投影技术有助于孤立性肺结节的定性诊断,多平面重建技术的价值优于最大密度投影技术。     

16层螺旋CT不同剂量扫描对肺结节诊断价值及辐射度的影响

目的:探讨16层螺旋CT不同剂量扫描对肺结节诊断价值及辐射度的影响。方法:选取2017年9月至2018年10月期间在青岛市中心医院就诊的肺结节患者200例,所有患者均接受16层螺旋CT常规剂量扫描和低剂量扫描。比较常规剂量扫描和低剂量扫描的图像质量、CT征象检出情况(分叶征、毛刺征、胸膜凹陷征、血管集束征、支气管征)、肺结节定性诊断结果(肺癌、肺转移瘤、炎性结节、定性困难)、肺结节大小分布(≤5 mm、6-10 mm、10 mm)、辐射度。结果:常规剂量和低剂量的扫描图像质量整体比较差异无统计学意义(P0.05),常规剂量和低剂量的CT征象检出情况(分叶征、毛刺征、胸膜凹陷征、血管集束征、支气管征)比较差异无统计学意义(P0.05),常规剂量和低剂量的肺结节定性诊断结果(肺癌、肺转移瘤、炎性结节、定性困难)比较差异无统计学意义(P0.05),常规剂量和低剂量的肺结节大小分布(≤5 mm、6-10 mm、10 mm)比较差异无统计学意义(P0.05),低剂量的总管球剂量、有效管球剂量、CT容积剂量指数及剂量长度乘积均明显低于常规剂量,差异有统计学意义(P0.05)。结论:16层螺旋CT低剂量扫描对肺结节的诊断价值与常规剂量扫描相当,并可有效减少辐射度,值得临床推广应用。     

胸部CT结合AI诊断系统对疑似肺结节患者的诊断及对结节类型的评估价值

摘要 目的：探讨胸部CT结合AI诊断系统对疑似肺结节患者的诊断及对结节类型的评估价值。方法：选取2019年12月-2020年12月在我院进行CT检查的358例疑似肺结节患者,将其按照随机数字表法分为两组：对照组（放射科医生根据CT扫描结果,通过人工阅片分析记录检出结节数量和影像特征）,观察组（将CT扫描结果导入AI辅助诊断系统,经AI运算得到结节检出数量和影像特征）。AI辅助系统IMsight用于肺结节的图像分析和自动检测。通过组织病理学确定结节的良恶性。绘制受试者工作特征曲线（ROC）曲线以评估AI和CT结合图像的诊断价值。结果：病理结果最后确诊结节数量736个,恶性结节139个（18.89 %）,良性结节597个（81.11 %）。观察组诊断结节数量717个,检出率97.42%,对照组诊断出结节数量603个,检出率81.93 %。观察组较对照组的结节检出率、阳性检出率升高（P<0.05）,漏检率和假阴性率均显著降低（P<0.05）。当结节小于10 mm时,观察组较对照组的检出率升高（P<0.05）,观察组较对照组对磨玻璃密度结节和实性结节检出率升高（P<0.05）,观察组较对照组位于胸膜结节检出率升高（P<0.05）。观察组较对照组AUC（P<0.05）,表明AI系统下的结节检出准确率高。ROC曲线显示观察组的敏感性和特异性分别为88.39%和89.68 %,对照组的敏感性和特异性分别为75.24 %和82.34 %,观察组较对照组的ROC曲线敏感性和特异性升高（P<0.05）。结论：AI辅助诊断系统可有效提高肺结节的检出率,减少误检率及漏检率,值得在肺结节CT检测中应用推广。     

三维肺部图像中疑似肺结节结构的自动提取

本文提出了一种肺部CT图像三维数据中自动提取疑似结节区域的方法。首先结合阈值分割、种子填充等方法,在三维体数据上分割出肺实质。进而利用改进的模糊C均值聚类,提取出结节及具有结节特征的血管、支气管等感兴趣区域。该工作对感兴趣区域的特征提取有重要意义,是早期肺癌计算机辅助诊断重要的一步。     

螺旋CT增强扫描对孤立性肺结节的诊断价值

目的:研究螺旋CT增强扫描时孤立性肺结节的诊断价值。方法:回顾分析经病理证实的恶性结节50例、炎性结节26例、结核瘤12例的螺旋CT增强扫描的表现。结果:恶性结节和炎性结节增强扫描的强化程度明显高于结核瘤(P＜0．05)。炎性结节强化峰值的时间较恶性结节延迟。恶性结节增强扫描出现点、条状及边缘强化。结论:螺旋CT增强扫描对孤立性肺结节的诊断具有重要临床应用价值。     

探讨CT技术在肺结节疾病诊断中的应用

目的：探讨CT技术在肺结节疾病诊断中的应用。利用CT技术提供的影像学特征,及时准确的诊断肺结节疾病,从而更具体更全面的提高对该疾病的认识,减少误诊的发生。方法：回顾性分析我院2010年-2012年确诊的符合相应临床诊治标准的肺结节患者48例的临床资料,通过CT扫描分析其具体的特征表现。结果：在所选的48例中,纵隔淋巴结增大45例,双侧肺门淋巴结增大44例,胸部淋巴结增大患者48例。肺部病变者33例,其中单发结节患者2例,多发结节患者25例,支气管血管束增粗者14例,磨玻璃样影案例者9例,实变案例5例。胸膜病发患者13例。结论：我们通过分析发现,胸部有典型影像学表现形式的肺结节病例诊断较容易,无典型影像学表现的患者诊断较为困难。因此我们认为利用CT技术诊断肺结节疾病具有特异性意义,值得临床医生重视。     

128层螺旋CT 低剂量扫描检查孤立性肺内结节性病灶的研究

目的:探讨多排螺旋CT(128排)低剂量扫描参数下检查孤立性肺内结节的可行性研究。方法:随机连续搜集我院低剂量(30m A)CT肺体检者,发现肺内结节病灶患者13例,对其进一步以常规剂量(350m A)CT精细扫描,比较低剂量扫描及常规剂量扫描肺结节大小差异。结果:两种剂量扫描策略均检查出46枚结节。常规剂量与低剂量测得各部位结节体积分别为:肺尖部:(431.3±92.8)mm~3,(658.4±94.4)mm~3,肺中部:(3025.8±526.7)mm~3,(2989.4±520.4)mm~3,肺底部:(1241.5±438.9)mm~3,(1266.0±447.6)mm~3,肺尖部肺结节大小差异明显,肺中部及肺底部肺结节大小均无显著性差异(P0.05)。常规剂量与低剂量测得结节体积(除外肺尖部位结节5枚)分别为,组1:(39.8±14.6)mm~3,(40.7±15.5)mm~3;组2:(202±106.3)mm~3,(204.1±103.6)mm~3;组3:(4179.7±4410.4)mm~3,(4190.5±4487.2)mm~3。三组组内测量结果均无显著性差异(P0.05)。常规剂量与低剂量测得非实性结节密度[(-68.3±24.2)HU,(-64.6±22.8)HU]及实性结节结节密度[(97.5±69.5)HU,(107.2±90)HU]均无统计学差异(P0.05)。结论:低剂量更加有利于肺内孤立结节患者扫描复查病灶,可以应用推广。     

高分辨MSCT薄层重组在常规胸部体检中的应用

目的：探讨多排螺旋CT（MSCT）高分辨薄层重组对体检中肺部疾病的诊断价值,以及MSCT薄层重组与常规CT扫描图像质量及诊断准确率对照。方法：搜集做64排常规CT扫描同时行薄层重组的2473例体检病例中筛选的97例患者进行回顾性分析。结果：97例患者在常规CT扫描中有80例可以显示病变,而在MSCT薄层重组中97例均有阳性发现;其中双肺弥漫性病变79例（两肺间质纤维化78例,肺内多发转移瘤1例）,肺结核3例,肺内孤立结节12例,早期中央型肺癌1例,先天性支气管闭锁1例以及纵隔肿瘤1例;MSCT薄层重组图像可清晰显示肺内小叶间隔线增厚、弥漫分布的囊性病变、肺内结节的细微征象。结论：MSCT薄层重组在胸部体检中的诊断阳性率、细节分辨率、图像质量及确诊率均优于常规CT,可作为肺内病变尤其是早期肺癌筛查方法之首选。     

高分辨MSCT 薄层重组在常规胸部体检中的应用

目的:探讨多排螺旋CT(MSCT)高分辨薄层重组对体检中肺部疾病的诊断价值,以及MSCT薄层重组与常规CT扫描图像质量及诊断准确率对照。方法:搜集做64排常规CT扫描同时行薄层重组的2473例体检病例中筛选的97例患者进行回顾性分析。结果:97例患者在常规CT扫描中有80例可以显示病变,而在MSCT薄层重组中97例均有阳性发现;其中双肺弥漫性病变79例(两肺间质纤维化78例,肺内多发转移瘤1例),肺结核3例,肺内孤立结节12例,早期中央型肺癌1例,先天性支气管闭锁1例以及纵隔肿瘤1例;MSCT薄层重组图像可清晰显示肺内小叶间隔线增厚、弥漫分布的囊性病变、肺内结节的细微征象。结论:MSCT薄层重组在胸部体检中的诊断阳性率、细节分辨率、图像质量及确诊率均优于常规CT,可作为肺内病变尤其是早期肺癌筛查方法之首选。     

慢性阻塞性肺疾病合并肺曲菌病一例及文献复习

目的:提高对慢性阻塞性肺疾病合并侵袭性肺曲菌病(COPD合并IPA)临床特点、诊断及治疗的认识.方法:回顾性分析2011年4月收治的一例COPD合并IPA患者的临床资料及诊治经过,并复习相关文献.结果:男患,“咳嗽、咳痰30余年,气短3年,加重1月余”入院,肺部CT示双肺多发结节影、空洞影,经抗炎、抗念珠菌治疗无效,CT下肺结节病灶活检病理示肺曲菌.抗曲菌治疗后症状好转、肺部影像明显吸收.结论:COPD合并IPA正逐渐引起重视,临床特征无明显特异性,肺部影像以结节影、空洞影多见,早期常规治疗无效时应积极抗曲菌治疗,可明显改善症状,降低死亡率,病理活检是确诊的依据.     

高分辨率CT与常规CT检查对肺小结节及早期肺癌诊断价值的对比研究

目的:对比高分辨率电子计算机断层扫描(CT)与常规CT检查对肺小结节及早期肺癌的诊断价值。方法:将2018年6月2020年1月我院收治的肺小结节及早期肺癌患者94例纳入研究。以随机数字表法将其分为观察组及对照组,每组各47例,对照组实施常规CT检查,观察组则实施高分辨率CT检查。比较两组CT肿瘤征象情况(主要包括毛刺征、分叶征、棘突征、钙化征、空泡征、支气管征、胸膜凹陷征、血管集束征),CT扫描图像质量,诊断肺小结节及早期肺癌的效能。结果:观察组各项CT肿瘤征象人数占比均高于对照组(P<0.05)。观察组CT扫描图像质量优良率为97.87%(46/47),高于对照组的72.34%(34/47)(P<0.05)。高分辨率CT诊断早期肺癌的灵敏度及准确度、特异度分别为96.67%(29/30)、95.74%(45/47)、94.12%(16/17),高于常规CT检查的74.19%(23/31)、74.47%(35/47)、75.00%(12/16)。结论:高分辨率CT检查对肺小结节及早期肺癌诊断价值显著高于常规CT检查,可作为临床肺小结节及早期肺癌诊断的有效影像学手段,值得临床应用。     

Can Spectral CT Imaging Improve the Differentiation between Malignant and Benign Solitary Pulmonary Nodules?

Purpose

To quantitatively assess the value of dual-energy CT (DECT) in differentiating malignancy and benignity of solitary pulmonary nodules.

Materials and Methods

Sixty-three patients with solitary pulmonary nodules detected by CT plain scan underwent contrast enhanced CT scans in arterial phase (AP) and venous phase (VP) with spectral imaging mode for tumor type differentiation. The Gemstone Spectral Imaging (GSI) viewer was used for image display and data analysis. Region of interest was placed on the relatively homogeneous area of the nodule to measure iodine concentration (IC) on iodine-based material decomposition images and CT numbers on monochromatic image sets to generate spectral HU curve. Normalized IC (NIC), slope of the spectral HU curve (λ_HU) and net CT number enhancement on 70keV images were calculated. The two-sample t-test was used to compare quantitative parameters. Receiver operating characteristic curves were generated to calculate sensitivity and specificity.

Results

There were 63 nodules, with 37 malignant nodules (59%) and 26 benign nodules (41%). NIC, λ_HU and net CT number enhancement on 70keV images for malignant nodules were all greater than those of benign nodules. NIC and λ_HU had intermediate to high performances to differentiate malignant nodules from benign ones with the areas under curve of 0.89 and 0.86 respectively in AP, 0.96 and 0.89 respectively in VP. Using 0.30 as a threshold value for NIC in VP, one could obtain sensitivity of 93.8% and specificity of 85.7% for differentiating malignant from benign solitary pulmonary nodules. These values were statistically higher than the corresponding values of 74.2% and 53.8% obtained with the conventional CT number enhancement.

Conclusions

DECT imaging with GSI mode provides more promising value in quantitative way for distinguishing malignant nodules from benign ones than CT enhancement numbers.     

PET-CT在非完全实性肺结节中的应用价值

肺癌在中国恶性肿瘤的发病率位居第一,随着低剂量薄层CT在肺癌筛查中的广泛应用,临床发现更多表现为非完全实性结节的肺腺癌,目前众多研究使CT影像学特征和肺腺癌病理的关系得到更进一步的认知,虽然CT能对部分非完全实性结节做出定性和定位诊断,但仍有部分非完全实性结节诊断困难,PET-CT结合了病灶的代谢信息和精确的定位信息,从而提高对肺部结节诊断的敏感性、特异性、准确性,综合多个文献PET-CT在非完全实性结节中的诊断分期价值较CT无明显提升,却在评估预后和制定合适手术方案上可以起到一定的作用,本文就PET-CT在SSN中的应用价值进行阐述。     

Ultra-High-Resolution Computed Tomography of the Lung: Image Quality of a Prototype Scanner

PurposeThe image noise and image quality of a prototype ultra-high-resolution computed tomography (U-HRCT) scanner was evaluated and compared with those of conventional high-resolution CT (C-HRCT) scanners.ResultsThe image noise for U-HRCT (100.87 ± 0.51 Hounsfield units [HU]) was greater than that for C-HRCT (40.41 ± 0.52 HU; P < .0001). The image quality of U-HRCT was graded as superior to that of C-HRCT (P < .0001) for all of the following parameters that were examined: margins of subsolid and solid nodules, edges of solid components and pulmonary vessels in subsolid nodules, air bronchograms, pleural indentations, margins of pulmonary vessels, edges of bronchi, and interlobar fissures.ConclusionDespite a larger image noise, the prototype U-HRCT scanner had a significantly better image quality than the C-HRCT scanners.     

18F-fluoro-deoxy-glucose focal uptake in very small pulmonary nodules: fact or artifact? Case reports

ABSTRACT: BACKGROUND: F-fluoro-deoxy-glucose (18F-FDG) positron emission tomography integrated/combined with computed tomography (PET-CT) provides the best diagnostic results in the metabolic characterization of undetermined solid pulmonary nodules. The diagnostic performance of 18F-FDG is similar for nodules measuring at least 1 cm and for larger masses, but few data exist for nodules smaller than 1 cm. CASE PRESENTATION: We report five cases of oncologic patients showing focal lung 18F-FDG uptake on PET-CT in nodules smaller than 1 cm. We also discuss the most common causes of 18F-FDG false-positive and false-negative results in the pulmonary parenchyma. In patient 1, contrast-enhanced CT performed 10 days before PET-CT did not show any abnormality in the site of uptake; in patient 2, high-resolution CT performed 1 month after PET showed a bronchiole filled with dense material interpreted as a mucoid impaction; in patient 3, contrast-enhanced CT performed 15 days before PET-CT did not identify any nodules; in patients 4 and 5, contrast-enhanced CT revealed a nodule smaller than 1 cm which could not be characterized. The 18F-FDG uptake at follow-up confirmed the malignant nature of pulmonary nodules smaller than 1 cm which were undetectable, misinterpreted, not recognized or undetermined at contrast-enhanced CT. CONCLUSION: In all five oncologic patients, 18F-FDG was able to metabolically characterize as malignant those nodules smaller than 1 cm, underlining that: 18F-FDG uptake is not only a function of tumor size but it is strongly related to the tumor biology; functional alterations may precede morphologic abnormalities. In the oncologic population, especially in higher-risk patients, PET can be performed even when the nodules are smaller than 1 cm, because it might give an earlier characterization and, sometimes, could guide in the identification of alterations missed on CT.     

不同放射剂量CT在早期非小细胞肺癌中筛检价值对比

摘要 目的：探讨与对比不同放射剂量计算机断层扫描(Computed Tomography,CT)在早期非小细胞肺癌中筛检价值。方法：2020年1月到2020年12月选择在本院经病理确诊为肺内磨玻璃样结节患者98例作为研究对象,所有患者都给予常规剂量正电子发射计算机断层扫描(Positron emission tomography,PET)/CT检查与低剂量PET/CT检查,记录成像特征、辐射剂量并判定筛检价值。结果：低剂量PET/CT对肺部增厚、边界不规则、钙化、囊变的检出率高于常规剂量PET/CT(P<0.05)。低剂量PET/CT与常规剂量PET/CT的图像质量优良率为98.0 %和96.9 %,对比差异无统计学意义(P>0.05)。低剂量PET/CT的有效放射剂量、剂量长度乘积低于常规剂量PET/CT(P<0.05)。低剂量PET/CT的最大标准摄取值(maximum standardized uptake value,SUVmax)值低于常规剂量PET/CT(P<0.05)。低剂量PET/CT与常规剂量PET/CT分别筛检非小细胞肺癌51例与37例,筛检敏感性分别为98.1 %和69.2 %,特异性分别为100.0 %和97.8 %。结论：低放射剂量PET/CT在肺结节中的应用不会影响图像质量,且能降低辐射剂量,提高对早期非小细胞肺癌患者的筛检效果。     

直径小于1 cm孤立性肺结节的18F-FDG PET/CT诊断研究进展

孤立性肺结节的鉴别诊断一直是胸部影像学的研究热点。早期且准确地鉴别肺内小结节的良恶性,对于患者治疗方案的确定以及随访情况的评估均具有重要的临床意义。~(18)F-FDG PET/CT在鉴别诊断恶性肿瘤方面具有明显优于其他传统检查的高特异性和高敏感性,其公认的恶性肿瘤的诊断阈值是最大化标准摄取值(maximum standard uptake value, SUVmax)为2.5,然而部分临床数据显示一些直径小于1 cm的恶性肺结节的SUVmax数值小于2.5。因此在早期研究中,~(18)F-FDG PET/CT在诊断直径较小的肺结节的其临床价值仍存在争议。为了尽量降低SUVmax的测量误差,提高~(18)F-FDG PET/CT诊断的准确率,衍生出了许多SUVmax辅助诊断方法以及优化的重建算法、放射性显像剂的联合应用等手段。本文将对~(18)F-FDG PET/CT鉴别诊断直径小于1 cm孤立性肺结节的研究进展进行综述。     

Automatic detection of pulmonary nodules in CT images by incorporating 3D tensor filtering with local image feature analysis

Computer-aided detection (CAD) technology has been developed and demonstrated its potential to assist radiologists in detecting pulmonary nodules especially at an early stage. In this paper, we present a novel scheme for automatic detection of pulmonary nodules in CT images based on a 3D tensor filtering algorithm and local image feature analysis. We first apply a series of preprocessing steps to segment the lung volume and generate the isotropic volumetric CT data. Next, a unique 3D tensor filtering approach and local image feature analysis are used to detect nodule candidates. A 3D level set segmentation method is used to correct and refine the boundaries of nodule candidates subsequently. Then, we extract the features of the detected candidates and select the optimal features by using a CFS (Correlation Feature Selection) subset evaluator attribute selection method. Finally, a random forest classifier is trained to classify the detected candidates. The performance of this CAD scheme is validated using two datasets namely, the LUNA16 (Lung Nodule Analysis 2016) database and the ANODE09 (Automatic Nodule Detection 2009) database. By applying a 10-fold cross-validation method, the CAD scheme yielded a sensitivity of 79.3% at an average of 4 false positive detections per scan (FP/Scan) for the former dataset, and a sensitivity of 84.62% and 2.8 FP/Scan for the latter dataset, respectively. Our detection results show that the use of 3D tensor filtering algorithm combined with local image feature analysis constitutes an effective approach to detect pulmonary nodules.