Solitary pulmonary nodules: dynamic enhanced multi-detector row CT study and comparison with vascular endothelial growth factor and microvessel density

PURPOSE: To evaluate enhancement dynamics of solitary pulmonary nodules at multi-detector row computed tomography (CT) and to correlate results with extent of tumor angiogenesis in pathologic specimens. MATERIALS AND METHODS: One hundred thirty-one patients with solitary pulmonary nodules underwent unenhanced thin-section CT, followed by dynamic helical CT (throughout the nodule for 30 mm along the z-axis [13 images] and at 20-second intervals for 3 minutes [130 images total]) after intravenous injection of 120 mL of contrast medium. Diagnosis of malignancy or benignancy was assigned in 109 patients, and follow-up imaging suggested benignancy in the remaining 22. CT findings were analyzed for peak attenuation, net enhancement, and enhancement dynamics. In 54 patients with surgical diagnoses, Pearson correlation coefficient was used to correlate enhancement pattern with extent of microvessel density and vascular endothelial growth factor (VEGF) staining. RESULTS: With 30 HU or more of net enhancement as a cutoff value in differentiation of malignant and benign nodules, sensitivity for malignant nodules was 99% (69 of 70 malignant nodules), specificity was 54% (33 of 61 benign nodules), positive predictive value was 71% (69 of 97 malignant readings), negative predictive value was 97% (33 of 34 benign readings), and accuracy was 78% (102 of 131 nodules). Peak attenuation was correlated positively with extent of microvessel density (r = 0.369, P =.006) and VEGF staining (r = 0.277, P =.042). Malignant nodules showed significantly higher VEGF expression (P =.009) than that of benign nodules. CONCLUSION: Dynamic enhancement with multi-detector row CT shows high sensitivity and negative predictive values for diagnosis of malignant nodules but low specificity because of highly enhancing benign nodules. Extent of enhancement reflects underlying nodule angiogenesis.     

Thin-section CT features of intrapulmonary lymph nodes

PURPOSE: The objective of this study was to evaluate CT findings of pathologically proven intrapulmonary lymph nodes (IPLNs) and discuss the utility of thin-section CT and contrast-enhanced CT. METHOD: CT findings of 18 nodules in 14 patients with pathologically proven IPLNs were reviewed. CT scanning of the whole lung was performed contiguously with slice thickness of 10 mm. In addition, a helical scan with slice thickness of 2 mm was performed in nine patients, focusing on the nodule. Contrast-enhanced helical CT was performed in four patients, and the utility of thin section CT and contrast-enhanced CT was investigated. RESULTS: One patient had three nodules, 2 patients had two nodules, and the remaining 11 patients had a solitary nodule. All nodules were located below the level of the carina and within 15 mm of the pleura. In one case, conventional CT revealed the nodule 20 mm away from the pleura; however, the nodule attached to the major fissure was clearly revealed on thin-section CT. The size of the nodules was < or =15 mm, and the shape was round (n = 8), oval (n = 9), or lobulated (n = 1) with sharp border. One nodule demonstrated a spiculated border due to a surrounding pulmonary fibrosis on conventional CT; however, thin-section CT showed precisely a sharp border. The lobulated shape of one case histopathologically reflected a hilus of lymph node. On contrast-enhanced helical CT, all four nodules were enhanced and the degree enhancement was 36-85 HU (median 66.6 HU). CONCLUSION: In current times, IPLNs are not uncommon lesions. We should consider IPLN in the differential diagnosis of solitary or multiple pulmonary nodules in the peripheral field and below the level of the carina. Thin-section CT showed precisely the border or relation between IPLNs and the surrounding structure. It was difficult to distinguish between IPLNs and malignant nodules from the degree of enhancement on contrast-enhanced CT. On thin-section and contrast-enhanced CT, the findings of IPLNs are not necessarily specific. Therefore, strict observation on CT is necessary; in certain cases that are increasing in size, video-assisted thoracic surgery should be considered because of their location.     

Solitary pulmonary nodules: comparison of classification with standard, thin-section, and reference phantom CT

Standard, thin-section, and reference phantom computed tomography (CT) were performed to evaluate 75 consecutive patients with solitary pulmonary nodules. Follow-up was available for 62 nodules in 59 patients; 53 of the nodules were benign and nine were malignant. Twenty-one of the 62 nodules were assessed as benign with thin-section CT, while 33 of the 62 nodules were assessed as benign with reference phantom CT. Two of the nodules classified as benign with both thin-section and reference phantom CT proved to be malignant (a peripheral, ossified carcinoid and a 3.5-cm-diameter calcified carcinoma). The sensitivity of reference phantom CT (58%) for classification of benign nodules was higher than the sensitivity of thin-section CT (36%). The sensitivity of standard CT was lowest (12%). The presence of fat at thin-section CT was a reliable criterion for benignancy in six hamartomas. While both thin-section and reference phantom CT were useful in the identification of benign pulmonary nodules, reference phantom CT increased sensitivity by 22% compared with thin-section CT.     

CT diagnosis of solitary pulmonary nodule]

The CT (including HRCT) findings of solitary pulmonary nodule (SPN) were reviewed. CT currently is the imaging modality of choice for the evaluation of SPN. Important roles of CT are detecting pulmonary nodules and distinguishing malignant nodules from other benign tumors or inflammatory masses. To differentiate malignancy from benignancy, it is necessary to evaluate the CT findings of SPN, including morphology using HRCT, attenuation of the nodules using thin-section CT, and enhancement effect on contrast-enhanced CT. Also important in this distinction is the evaluation of satellite lesions around SPN and the relationships between bronchus, artery, vein, pleura, and interlobular septum. Spiral CT has greatly expanded the usefulness of CT in the evaluation of SPN and has become the imaging modality of choice for SPN by combining the advantages of a single breath-hold acquisition and improved MPR and three-dimensional reconstruction capabilities. MPR and three-dimensional images of spiral CT can also be used to display the three-dimensional relationship between SPNs and bronchus, vessels, or pleura.     

Solitary pulmonary nodule: CT evaluation of enhancement with iodinated contrast material--a preliminary report.

The authors hypothesized that the degree of contrast material enhancement of a pulmonary nodule, measured with computed tomography (CT), may indicate the likelihood of malignancy. Fifty-two patients with uncalcified solitary pulmonary nodules (diameter, 6-30 mm) were studied. Five single serial thin-section CT scans were obtained at 1-minute intervals after injection of 100 mL of nonionic contrast material. Twenty-two patients were excluded because the diagnosis was not clearly established: The observation period was less than 2 years, or the examination was technically inadequate. Malignant nodules were identified in 23 of the 30 remaining patients, and benign nodules were identified in seven. Within the first 2 minutes after the injection, all the malignant nodules had enhanced by 20 HU or greater (only one benign nodule had that degree of enhancement). The authors conclude that the degree of contrast material enhancement of pulmonary nodules as measured with CT may indicate the likelihood of malignancy.     

Thin-section multiplanar reformats from multidetector-row CT data: utility for assessment of regional tumor extent in non-small cell lung cancer

PURPOSE: To determine the clinical utility of thin-section multiplanar reformats (MPRs) from multidetector-row CT (MDCT) data sets for assessing the extent of regional tumors in non-small cell lung cancer (NSCLC) patients. MATERIALS AND METHODS: Sixty consecutive NSCLC patients, who were considered candidates for surgical treatment, underwent contrast-enhanced MDCT examinations, surgical resection and pathological examinations. All MDCT examinations were performed with a 4-detector row computed tomography (CT). From each raw CT data set, 5mm section thickness CT images (routine CT), 1.25 mm section thickness CT images (thin-section CT) and 1.25 mm section thickness sagittal (thin-section sagittal MPR) and coronal images (thin-section coronal MPR) were reconstructed. A 4-point visual score was used to assess mediastinal, interlobar and chest wall invasions on each image set. For assessment of utility in routine clinical practice, mean reading times for each image set were compared by means of Fisher's protected least significant difference (PLSD) test. A receiver operator characteristic (ROC) analysis was performed to determine the diagnostic capability of each of the image data sets. Finally, sensitivity, specificity and accuracy of the reconstructed images were compared by McNemar test. RESULTS: Mean reading times for thin-section sagittal and coronal MPRs were significantly shorter than those for routine CT and thin-section CT (p<0.05). Areas under the curve (Azs) showing interlobar invasion on thin-section sagittal and coronal MPRs were significantly larger than that on routine CT (p=0.03), and the Az on thin-section sagittal MPR was also significantly larger than that on routine CT (p=0.02). Accuracy of chest wall invasion by thin-section sagittal MPR was significantly higher than that by routine CT (p=0.04). CONCLUSION: Thin-section multiplanar reformats from multidetector-row CT data sets are useful for assessing the extent of regional tumors in non-small cell lung cancer patients.     

Computer-assisted lung nodule volumetry from multi-detector row CT: influence of image reconstruction parameters

PURPOSE: To investigate differences in volumetric measurement of pulmonary nodules caused by changing the reconstruction parameters for multi-detector row CT. MATERIALS AND METHODS: Thirty-nine pulmonary nodules less than 2 cm in diameter were examined by multi-slice CT. All nodules were solid, and located in the peripheral part of the lungs. The resultant 48 parameters images were reconstructed by changing slice thickness (1.25, 2.5, 3.75, or 5 mm), field of view (FOV: 10, 20, or 30 cm), algorithm (high-spatial frequency algorithm or low-spatial frequency algorithm) and reconstruction interval (reconstruction with 50% overlapping of the reconstructed slices or non-overlapping reconstruction). Volumetric measurements were calculated using commercially available software. The differences between nodule volumes were analyzed by the Kruskal-Wallis test and the Wilcoxon Signed-Ranks test. RESULTS: The diameter of the nodules was 8.7+/-2.7 mm on average, ranging from 4.3 to 16.4mm. Pulmonary nodule volume did not change significantly with changes in slice thickness or FOV (p>0.05), but was significantly larger with the high-spatial frequency algorithm than the low-spatial frequency algorithm (p<0.05), except for one reconstruction parameter. The volumes determined by non-overlapping reconstruction were significantly larger than those of overlapping reconstruction (p<0.05), except for a 1.25 mm thickness with 10 cm FOV with the high-spatial frequency algorithm, and 5mm thickness. The maximum difference in measured volume was 16% on average between the 1.25 mm slice thickness/10 cm FOV/high-spatial frequency algorithm parameters and overlapping reconstruction. CONCLUSION: Volumetric measurements of pulmonary nodules differ with changes in the reconstruction parameters, with a tendency toward larger volumes in high-spatial frequency algorithm and non-overlapping reconstruction compared to the low-spatial frequency algorithm and overlapping reconstruction.     

CT征象联合肿瘤标志物对孤立性肺结节良恶性的鉴别诊断分析

目的 探讨CT征象联合肿瘤标志物对孤立性肺结节良恶性的鉴别诊断价值.方法 选取70例孤立性肺结节患者,行高分辨率CT、肿瘤标志物检查及病理检查.以病理组织学检查结果分为恶性结节组39例,良性结节组31例,对比两组CT征象和肿瘤标志物水平差异,运用受试者工作特征曲线(ROC)分析CT联合肿瘤标志物检测鉴别孤立性肺结节良恶...     

Solitary pulmonary nodule: characterization with combined wash-in and washout features at dynamic multi-detector row CT

PURPOSE: To prospectively assess the accuracy of combined wash-in and washout characteristics at dynamic contrast material-enhanced multi-detector row computed tomography (CT) in distinguishing benign from malignant solitary pulmonary nodules. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. The study included 107 patients (62 men, 45 women; mean age, 55 years; range, 22-81 years) with a solitary pulmonary nodule. After unenhanced CT (2.5-mm collimation) scans were obtained, dynamic CT was performed by using a helical technique (series of images obtained throughout the nodule, with 2.5-mm collimation, at 30, 60, 90, and 120 seconds and 4, 5, 9, 12, and 15 minutes) after intravenous injection of contrast medium (120 mL). Tissue diagnosis was made in 70 nodules, and follow-up images showed benignancy in the remaining 37 (no change in size, n = 32; decrease in size, n = 5). CT findings were analyzed in terms of wash-in and washout of contrast medium. Sensitivity, specificity, and accuracy for malignant nodules were calculated by considering both the wash-in and washout characteristics at dynamic CT. RESULTS: There were 49 malignant and 58 benign nodules. When diagnostic criteria for malignancy of both wash-in of 25 HU or greater and washout of 5-31 HU were applied, sensitivity, specificity, and accuracy for malignancy were 94% (46 of 49 nodules), 90% (52 of 58 nodules), and 92% (98 of 107 nodules), respectively. Of 58 benign nodules, 27 showed less than 25 HU wash-in, 14 showed persistent contrast enhancement without washout and with wash-in of 25 HU or greater, and 11 showed washout greater than 31 HU and wash-in of 25 HU or greater. CONCLUSION: Evaluation of solitary pulmonary nodules by analyzing combined wash-in and washout characteristics at dynamic contrast-enhanced multi-detector row CT showed 92% accuracy for distinguishing benign nodules from malignant nodules.     

CT的形态学征象联合影像组学特征诊断模型在肺结节诊断中的应用

目的结合肺结节CT形态学征像与影像组学特征建立联合诊断模型,期望提高孤立性肺结节的诊断准确性。方法选取2012年2月~2019年1月206例肺实性结节(直径≤2cm)的CT图像。由两名医师独立进行形态学征像评估,并诊断结节良恶性,使用PyRadiomics开源软件提取、筛选定量影像组学特征,采用逻辑回归建立影像组学模型,并融合形态学征像建立联合诊断模型,采用受试者操作特征(ROC)曲线评价模型诊断效能,并与人工诊断结果进行比较。结果结节的血管集束、支气管截断、毛刺、分叶、胸膜牵拉、空泡征及充气支气管征在恶性结节中的检出率高,与良性结节之间的差异有统计学意义(P<0.05);结节越小,各种CT征像检出率越低。两位医师对肺结节征像识别一致性存在差异,高年资医师诊断效能明显高于低年资医师,曲线下面积(AUC)分别为0.81(95%CI,0.744~0.856),0.69(95%CI,0.623~0.753)。影像组学诊断模型对良恶性肺结节具有较高的鉴别诊断效能,AUC为0.86(95%CI,0.8~0.92),结合毛刺征、分叶征、胸膜牵拉征及影像组学特征建立联合诊断模型,进一步提高肺结节诊断效能,AUC为0.92(95%CI,0.87~0.96)。结论结合肺结节CT形态学征像及影像组学特征建立的联合诊断模型,在肺结节良恶性鉴别诊断中有较高的应用价值。     

Petrosal bone: coronal reconstructions from axial spiral CT data obtained with 0.5-mm collimation can replace direct coronal sequential CT scans.

PURPOSE: To investigate whether coronal multiplanar reconstruction (MPR) images of the petrosal bone from axial spiral computed tomographic (CT) data obtained with 0.5-mm collimation can replace direct coronal sequential CT scans obtained with 0.5- or 1.0-mm collimation. MATERIALS AND METHODS: The differences in diagnostic quality between thin-section coronal sequential CT scans of 24 petrosal bones in 12 patients and matched MPR images were assessed by five observers. The matched MPR images were calculated with both trilinear and tricubic interpolation. Image resolution was determined by measuring the three-dimensional point spread function. RESULTS: All observers preferred tricubically interpolated MPR images over trilinearly interpolated images. Subjective differences in image quality between direct coronal scans and matched tricubically interpolated MPR images were small. Only the direct coronal scans with the highest image quality (0.5-mm collimation, 465 mAs) were judged to be slightly better than the matched MPR images. With regard to direct coronal scans obtained at 245 mAs and/or 1.0-mm collimation, either there was no preference or the MPR images were preferred. CONCLUSION: Coronal MPR images from axial spiral CT obtained with 0.5-mm collimation can replace direct coronal sequential CT scans.     

Spiral CT of the lung in children with malignant extra-thoracic tumors: distribution of benign vs malignant pulmonary nodules

The purpose of this paper is to clarify the distribution of benign vs malignant pulmonary nodules which are seen on spiral CT in children with malignant extra-thoracic solid tumors. Seventy-four children with known solid, extra-thoracic tumors underwent spiral CT of the chest. According to the initial and follow-up (interval 9.2 ± 4.7 months) findings, the children were graded into four groups: I = normal; II = solitary nodule unchanged at follow-up; III = multiple nodules with one or more than one unchanged at follow-up; and IV = solitary or multiple nodules all changed at follow-up. Nodules without change at follow-up were regarded as benign. Forty-nine children did present with normal pulmonary CT exams. In 7 cases solitary pulmonary nodules were found unchanged (group II) at follow-up and in 2 cases (group III) some of the nodules were stationary. Thus, 12 % (9 of 74) presented with at least one pulmonary nodule that did not change at follow-up. Solitary nodules (in groups II and IV) with a diameter < 5 mm were in 70 % (7 of 10) unchanged at follow-up and regarded as benign. In children with known solid extra-thoracic tumors at initial presentation, 70 % of solitary nodules ( < 5 mm) may be benign. To avoid overstaging, smaller solitary nodules must not automatically be regarded as metastases. Received: 9 November 1999; Revised: 31 January 2000; Accepted: 4 February 2000     

螺旋CT动态增强扫描对孤立性肺结节定性诊断的价值

目的:分析良恶性孤立性肺结节(SPN)的动态强化特点,探讨动态SCT增强扫描对SPN定性诊断的价值。方法:对50例SPN患者进行螺旋CT同层动态增强扫描,对比剂总量100ml,注射流率3ml/s,延迟15s开始扫描,至180s结束,测量结节中心增强前后的CT值,分析最大强化值及时间-密度曲线(TAC),全部病例经手术病理证实。结果:肺炎性结节及恶性结节均显著强化,肺炎性结节强化峰值的时间较肺癌结节延迟。恶性结节的TAC表现为陡峭的上升支后有一较长的平台期,炎性结节的TAC表现为上升支平缓,部分见降支。结核球等其它良性SPN无明显强化。结论:动态SCT增强扫描对SPN定性诊断有较高价值。SPN的强化峰值及TAC形态有助于良、恶性病变的鉴别诊断。     

Indeterminate solitary pulmonary nodules revealed at population-based CT screening of the lung: using first follow-up diagnostic CT to differentiate benign and malignant lesions

OBJECTIVE: We studied the role of the first follow-up diagnostic CT for differentiating benign and malignant lesions in indeterminate solitary pulmonary nodules revealed at CT screening for lung cancer in which a total of 13,786 CT examinations (46% in women and 54% in men; 46% were smokers; mean age, 62 years) were performed. MATERIALS AND METHODS: We reviewed thin-section CT findings on the initial diagnostic CT (lesion size; percentages of ground-glass-opacity areas of lesion; and presence or absence of lobulation, spiculation, air bronchogram, cavity, satellite lesions, pleural tag, concave margins, polygonal shape, and peripheral subpleural lesion) in 80 pulmonary nodules (36 malignancies and 44 benign lesions) of 80 patients. We evaluated changes in size (regression, no change, or growth) on the first follow-up CT performed 42-120 days (mean, 93 days) after the initial CT. RESULTS: The greatest accuracy (81%) with 89% sensitivity and 75% specificity for determining malignancy was attained with a combined criterion of growth of lesions or predominantly ground-glass-opacity lesions. Of all criteria that were specific to malignancy, the greatest sensitivity (50%) was achieved with a combination of growth or no change in size of lesions and predominantly ground-glass opacity and no concave margins. Of all criteria that were specific to benign lesions, the greatest sensitivity (45%) was attained with a combination of lesion regression or polygonal shape. CONCLUSION: Follow-up CT findings were useful, and a combination of findings on initial CT and follow-up CT was optimal for differentiating benign and malignant pulmonary nodules.     

A comparison of the diagnostic accuracy of 18F-FDG PET and CT in the characterization of solitary pulmonary nodules.

CT and PET are widely used to characterize solitary pulmonary nodules (SPNs). However, most CT accuracy studies have been performed with outdated technology and methods, and previous PET studies have been limited by small sample sizes and incomplete masking. Our objective was to compare CT and PET accuracy in veterans with SPN. METHODS: Between January 1999 and June 2001, we recruited 532 participants with SPNs newly diagnosed on radiography and untreated. The SPNs were 7-30 mm. All patients underwent (18)F-FDG PET and CT. A masked panel of 3 PET and 3 CT experts rated the studies on a 5-point scale. SPN tissue diagnosis or 2-y follow-up established the final diagnosis. RESULTS: A definitive diagnosis was established for 344 participants. The prevalence of malignancy was 53%. The average size was 16 mm. Likelihood ratios (LRs) for PET and CT results for combined ratings of either definitely benign (33% and 9% of patients, respectively) or probably benign (27% and 12%) were 0.10 and 0.11, respectively. LRs for PET and CT results for combined ratings of indeterminate (1% and 25%), probably malignant (21% and 39%), or definitely malignant (35% and 15%) were 5.18 and 1.61, respectively. Area under the receiver operating characteristic curve was 0.93 (95% confidence interval, 0.90-0.95) for PET and 0.82 (95% confidence interval, 0.77-0.86) for CT (P < 0.0001 for the difference). PET inter- and intraobserver reliability was superior to CT. CONCLUSION: Definitely and probably benign results on PET and CT strongly predict benign SPN. However, such results were 3 times more common with PET. Definitely malignant results on PET were much more predictive of malignancy than were these results on CT. A malignant final diagnosis was approximately 10 times more likely than a benign final diagnosis in participants with PET results rated definitely malignant.     

分类决策树辅助CT诊断孤立性肺结节的方法学研究

目的 应用分类与回归决策树(CART)算法构建CT显像鉴别良恶性孤立性肺结节(SPN)预测模型,探讨数据挖掘技术在SPN影像诊断中的应用价值.方法 分别提取12个临床指标和22个CT征象指标作为CART预测SPN良恶性的输入指标.连续性纳入自2003年7月至2006年7月间经病理证实的SPN,且术前行CT检查的患者116例,其中良性结节62例,恶性结节54例.采用CART建立用于预测良恶性SPN的分类决策树模型,并通过交互印证的方法计算该模型的诊断准确性.同时设低年资医师诊断组和高年资医师诊断组,采用盲法进行独立阅片判断SPN的良恶性.采用受试者操作特征(ROC)曲线比较3组间的诊断效能.结果 (1)成功建立了能够判断SPN良恶性的CART诊断模型,其中含有8条诊断规则,最低相对错误代价为0.199,CART对SPN具有决策意义的最重要的前3位决策指标为结节的毛刺征、患者年龄和病灶部位.(2)CART、高年资医师和低年资医师对SPN良恶性诊断的ROC曲线下面积分别为0.910±0.029、0.827±0.038、0.612±0.052.CART与低年资医师ROC曲线下面积差(DBF)=0.297,P＜0.01;与高年资医师DBF=0.083,P＜0.05;高年资医师与低年资医师DBF=0.214,P＜0.01.CART诊断效能高于高年资医师和低年资医师,高年资医师高于低年资医师.结论 CART是具有强大学习能力的数据挖掘工具,可以对SPN的良恶性进行正确判断,为实现人工智能在影像诊断中的应甩提供重要的方法学依据.     

动态增强CT扫描对孤立性肺结节的诊断价值

目的:探讨动态增强CT扫描对良、恶性孤立性肺结节(SPN)的诊断价值.方法:时40例SPN患者行同层动态CT增强扫描,分别在平扫及增强后30s、60s、120s和180s测量病灶的CT值,获得病灶的时间-密度曲线(TAC),并进行统计学分析.结果:小肺癌与肺炎性结节、结核瘤的平扫CT值无显著差异.增强扫描小肺癌与结核瘤的CT强化程度有显著差异,但炎性结节与小肺癌的CT强化程度无显著差异.小肺癌、炎性结节,结核瘤三种病变的TAC形态不同.结论:动态增强CT扫描能显示SPN的强化特征并有助于定性诊断,是鉴别SPN良、恶性的有效影像学方法.     

多层螺旋CT灌注成像在肺结节鉴别诊断中的应用

目的 探讨多层螺旋CT灌注成像在肺结节的良恶性鉴别诊断中的价值.方法 采用多层螺旋CT机对96例肺结节患者行灌注扫描,其中良性结节18例、炎性结节28例、恶性结节50例.以perfusion 3软件测定结节的血流量(BF),血容量(BV),平均通过时间(MTT),渗透表面积乘积(PS)以及拟合时间-密度曲线(TDC),采用灌注参数及曲线形态来评价结节的良恶性.结果 BF、BV在炎性结节与良性结节之间具有显著性差异(P＜0.05),炎性结节均大于良性结节.MTT在三组结节之间没有显著性差异(P＞0.05),PS在恶性结节与良性结节之间、以及良性与炎性结节之间具有显著性差异(P＜0.05),恶性结节与炎性结节均高于良性结节,三组不同性质结节之间的TDC曲线形态也不同.结论 CT灌注成像能够较准确的判断肺结节的性质,在良恶性鉴别诊断中具有重要意义.     

颞骨平行枕眶线多层螺旋CT扫描法及其价值

目的:探讨以平行枕眶线扫描图像为基础的常规轴位和冠状位MPR图像是否能够取代直接轴位和冠状位图像。方法:三位医师分别观察50例颞骨CT扫描图像,分析直接常规轴位(25例)、冠状位(25例)CT扫描图像和其相应的常规轴位、冠状位MPR图像显示颞骨结构的差异。结果:所有观察者均认为直接常规轴位、冠状位CT扫描图像略优于相应的轴位、冠状位MPR图像。直接轴位、冠状位CT扫描图像和相应的轴位、冠状位MPR图像的质量差异较小。结论:以平行枕眶线扫描图像为基础的常规轴位和冠状位MPR图像可取代直接轴位和冠状位扫描图像。     

Solitary pulmonary nodule diagnosis on CT: results of an observer study

RATIONALE AND OBJECTIVES: To investigate the performance of observers with different levels of experience in distinguishing between benign and malignant solitary pulmonary nodules (SPN) on CT, and to determine the effects on interpretation of three different conditions: image data alone, the addition of clinical data, and the addition of output from a computer-aided diagnosis (CAD) system. MATERIALS AND METHODS: 28 thin-section CT datasets of SPNs with proven diagnoses (15 malignant and 13 benign) were used to measure observer performance. Readers were categorized according to their experience and read the cases in random order. For each case readers were asked to assign a level of confidence on a scale from 0.0-1.0 (0.0 benign, 1.0 malignant) for the diagnosis of the nodule. Each reader scored the cases based on review of image data alone (phase 1), then with limited clinical data (phase 2), and finally with CAD output (phase 3). To assess performance, multiple reader multiple case (MRMC) receiver operating characteristic (ROC) analysis was used. RESULTS: 2 thoracic radiologists, 1 thoracic radiology fellow, 2 nonthoracic radiologists, and 3 radiology residents read the cases. The average area under the ROC curve for all readers (A(z)) at each stage was 0.68, 0.75, and 0.81, for image data alone, with clinical data, and with CAD output respectively. The difference in performance between phases (2 and 3) and (1 and 3) was significantly different (P = 0.018 and P = 0.020). However, the difference between phases (1 and 2) was not significantly different (P = 0.155). CONCLUSION: Diagnostic performance increased significantly with the addition of CAD output. With further validation CAD output may play a significant role in SPN management.