Computed tomography in the diagnosis of mechanic jaundice complicated with diseases of the distal common bile duct]

Computerized tomography (CT) is a noninvasive indirect method of instrumental investigation for imaging the liver, bile ducts and the adjacent organs. CT enables one to confirm objectively the mechanical nature of jaundice, to assess a degree and level of involvement of the biliary tract, to assess the nature and spreading of disease. CT sensitivity for the diagnosis of pancreatic head cancer was 78.8%, specificity-91.3%, that for choledocholithiasis--84.6%, specificity--96.7%. CT in jaundice made it possible to establish diagnosis at various levels of accuracy: from differentiation of mechanical and parenchymatous jaundices to preliminary assessment of malignant tumor resectability facilitating a choice of surgical tactics.     

双源CT三维重建前交叉韧带移植物新技术

目的:探讨双源CT(DSCT)三维重建前交叉韧带(anterior cruciate ligament,ACL)重建术后移植物的技术方法。方法:对30例ACL损伤后移植重建术后患者进行DSCT扫描,利用软件三维重建ACL移植物的三维图像,对图像效果进行分析。结果:采用设定的参数和方法,30例患者的ACL移植物均获得三维重现,其中24例获得清晰的移植物图像,6例移植物图像略模糊。结论:DSCT可以重建出移植术后ACL移植物的三维图像,对临床检验、评估重建技术、修正重建方法、实现解剖重建有重大价值。     

Accuracy of Lung Ultrasonography versus Chest Radiography for the Diagnosis of Adult Community-Acquired Pneumonia: Review of the Literature and Meta-Analysis

Lung ultrasonography (LUS) is being increasingly utilized in emergency and critical settings. We performed a systematic review of the current literature to compare the accuracy of LUS and chest radiography (CR) for the diagnosis of adult community-acquired pneumonia (CAP). We searched in Pub Med, EMBASE dealing with both LUS and CR for diagnosis of adult CAP, and conducted a meta-analysis to evaluate the diagnostic accuracy of LUS in comparison with CR. The diagnostic standard that the index test compared was the hospital discharge diagnosis or the result of chest computed tomography scan as a “gold standard”. We calculated pooled sensitivity and specificity using the Mantel-Haenszel method and pooled diagnostic odds ratio using the DerSimonian-Laird method. Five articles met our inclusion criteria and were included in the final analysis. Using hospital discharge diagnosis as reference, LUS had a pooled sensitivity of 0.95 (0.93-0.97) and a specificity of 0.90 (0.86 to 0.94), CR had a pooled sensitivity of 0.77 (0.73 to 0.80) and a specificity of 0.91 (0.87 to 0.94). LUS and CR compared with computed tomography scan in 138 patients in total, the Z statistic of the two summary receiver operating characteristic was 3.093 (P = 0.002), the areas under the curve for LUS and CR were 0.901 and 0.590, respectively. Our study indicates that LUS can help to diagnosis adult CAP by clinicians and the accuracy was better compared with CR using chest computed tomography scan as the gold standard.     

18F-FDG PET/CT 在宫颈癌诊断及分期中的临床价值

目的:探讨氟代脱氧葡萄糖(~(18)F-FDG)正电子发射断层显像/X线计算机体层成像仪(PET/CT)检查在局灶早期宫颈癌中的临床应用价值。方法:53例病理确诊为早期宫颈癌的患者行全身~(18)F-FDG PET/CT检查,并在检查结束10日内行广泛性全子宫切除术+双附件切除术+盆腔淋巴结清扫术,计算~(18)F-FDG PET/CT诊断宫颈原发部位肿瘤及盆腔淋巴结转移的敏感度,特异度与准确度。结果:~(18)F-FDG PET/CT检查诊断的宫颈原发部位肿瘤的敏感度为79.25%,特异度为86.79%,准确度为84.9%;以病人为单位诊断盆腔淋巴结转移的准确度为85.71%,特异度为97.87%;以淋巴结为单位诊断盆腔淋巴结转移的准确度为84.61%,特异度为99.00%。结论:PET/CT显像对宫颈癌诊断,分期诊断及盆腔淋巴结转移的检出具有重要临床意义。     

To the role of computed tomography in the algorithm of diagnosis of lung cancer

The paper summarizes the results of examination of 100 patients with malignant tumors of the lung. The results of X-ray study, linear tomography, and computed tomography (CT) used in the examination of patients with lung cancer were compared by using as an indicator the following parameters: to make diagnosis of lung cancer, to reveal mediastinal intergrowths, to detect enlarged lymph nodes, pulmonary metastases, and pleural lesions, to obtain information on tumor spread into the chest, to reveal growths into the vascular walls. To evaluate the efficiency of the techniques in solving the above diagnostic tasks, a statistical analysis including the estimation of their accuracy, specificity, and sensitivity was made. Recommendations for examination of patients with lung cancer were drawn up for therapeutic institutions of different types.     

Computed tomography in the evaluation of tumor regression after neoadjuvant therapy: X-ray surgery and X-ray morphological comparisons

An analysis was made of chest computed tomograms of 38 small-cell lung cancer patients subjected to radical surgical treatment after neoadjuvant therapy. CT data were compared with the findings of macro- and microscopic examination of surgical specimens. In 24 (63.2%) patients, computed tomograms made before surgery showed complete tumor response confirmed by gross examination in 22 (96.1%) of them. However, microscopic examination found cancer cells in 8 (33.3%) patients. In 2 (8.3%) patients, small residual tumors could be detected by sight, which was confirmed by pathological examination. In 14 (36.8%) patients with partial response, radiological and gross examination findings fully coincided. Nevertheless, in 2 (14.3%) cases the "residual tumor" appeared to be a segment of fibrocicatrical tissue under pathological examination. On the basis of the CT findings the values of diagnostic sensitivity, accuracy and specificity in tumor response evaluation were calculated which made up 87.5%, 68.4% and 54.5% respectively. With sufficiently high sensitivity, CT specificity is low. CT makes it possible to objectively define the response of small-cell lung cancer to neoadjuvant therapy. However, the conclusion about complete response to the treatment can be made only on the basis of a comprehensive evaluation of the results of all available investigation methods and pathological examination.     

胰腺癌患者血清CEA、CA242、CA199水平变化及联合诊断的ROC曲线分析

目的:探讨胰腺癌患者血清癌胚抗原(CEA)、糖类抗原242(CA242)、糖类抗原199(CA199)水平变化,并分析上述指标对胰腺癌的联合诊断价值,为胰腺癌的临床诊断提供参考。方法:选择2014年2月至2018年2月我院收治的186例胰腺癌患者(胰腺癌组)、89例胰腺炎患者(胰腺炎组)作为研究对象,并取同期来我院检查的268例健康人作为对照组。比较三组受试者的血清CEA、CA242、CA199水平变化,对比分析血清CEA、CA242、CA199的单一以及联合诊断的准确度、特异度以及灵敏度,并绘制ROC曲线以分析上述指标的诊断价值。结果:三组受试者血清CEA、CA242、CA199水平差异具有统计学意义(P<0.05)。且胰腺炎组和胰腺癌组的血清CEA、CA242、CA199水平明显高于对照组,胰腺癌组患者的血清CEA、CA242、CA199水平明显高于胰腺炎组,差异均有统计学意义(P<0.05)。ROC曲线结果显示,CEA诊断价值最大,CA199诊断价值最小。CEA是胰腺癌单项肿瘤标志物中敏感度最高的,为85.48%;特异度最高的为CA242(96.72%);三项肿瘤标志物联合诊断的准确度增加至92.27%,敏感度增加至95.16%,特异度相比略有下降。结论:与单一肿瘤标记物诊断胰腺癌相比,CEA、CA242、CA199联合诊断的敏感度和准确度均明显升高,可以明显改善胰腺癌的漏诊率,提高患者的生存率,具有较好的临床应用价值。     

Clinical experience with positron emission tomography with 2-fluorine, 18F-2-deoxy-d-glucose used for the diagnosis of malignant breast neoplasms

The aim of the study was to evaluate sensitivity and specificity of positron emission tomography (PET) and 18F-fluorodesoxyglucose (18F-FDG) in breast cancer diagnosis and to assess tumor dissemination. Sixty two patients were examined: 10 without mammary disease, 10 with fibrous cystic mastopathy, and 42 with breast cancer, which was hystologically verified. PET scanning was recorded in the "Whole body" mode 70-90 min later administration of 370-420 MBq 18F-FDG. It was shown that PET has a high diagnostic accuracy in breast cancer detection. There were no False-positive cases in our investigations. PET scanning in the "Whole body" mode was allowed to assess dissemination of tumor process with high accuracy. Metastatic involvement of local lymph nodes was detected in 82.8% cases and bone metastases--86% in cases.     

Diagnostic Performance of First-Pass Myocardial Perfusion Imaging without Stress with Computed Tomography (CT) Compared with Coronary CT Angiography Alone,with Fractional Flow Reserve as the Reference Standard

Coronary computed tomography angiography (CCTA) in combination with first-pass CT myocardial perfusion imaging (MPI) has a better diagnostic performance than CCTA alone, compared with invasive coronary angiography as the reference standard. The aim of this study was to investigate the additional diagnostic value of first-pass CT-MPI without stress for detecting hemodynamic significance of coronary stenosis, compared with invasive fractional flow reserve (FFR). We recruited 53 patients with suspected coronary artery disease undergoing both CCTA and first-pass CT-MPI without stress and invasive FFR, and 75 vessels were analyzed. We used the same raw data for CCTA and CT-MPI. First-pass CT-MPI was reconstructed by examining the diastolic signal densities as a bull’s eye map. Invasive FFR <0.8 was considered as positive. On per-vessel analysis, the area under the receiver operating characteristic curve for CCTA plus first-pass CT-MPI and CCTA alone was 0.81 (0.73–0.90) and 0.70 (0.61–0.81), respectively (P = 0.036). CCTA plus first-pass CT-MPI without stress showed 0.73 sensitivity, 0.74 specificity, 0.53 positive predictive value, and 0.87 negative predictive value for detecting hemodynamically significant coronary stenosis. First-pass CT-MPI without stress correctly reclassified 38% of CCTA false-positive vessels as true negative. First-pass CT-MPI without stress combined with CCTA demonstrated excellent diagnostic accuracy, compared with invasive FFR as the reference standard. This technique could complement CCTA for diagnosis of coronary artery disease.     

基于三维卷积神经网络的肺结节探测与定位方法

提出一种基于三维卷积神经网络对肺部计算机断层扫描图像(CT)进行肺结节自动探测及定位的方法.基于开源数据集LUNA16开展研究,对数据进行像素归一化、坐标转换等预处理,对正样本使用随机平移、旋转和翻转的方式进行扩充,对负样本进行随机采样.搭建了三维卷积神经网络并在训练过程中调整网络参数,直到得到性能最佳的网络.此外还设...     

x线断层容积成像技术在肺动脉畸形中的应用

目的：通过与常规x线胸片比较,探讨胸部x线断层容积成像技术在肺动脉畸形中的应用价值。方法：对20例临床及x线平片怀疑肺动脉畸形者,进一步进行胸部x线断层容积成像检查。其中11例被明确诊断为肺动脉畸形。以CT或超声心动结果为标准,对比两种图像对肺动脉畸形的明确诊断率,分析对比该11例患者的胸部x线断层容积成像图片和普通x线胸片,评价两种方法所获得的图像质量和图片优秀率。结果：20例疑似患者中,11例被CT或超声心动确诊为肺动脉畸形,其x线断层容积成像图片和普通x线胸片经主管技师和副主任医师双盲判读,x线断层容积成像11例均获明确诊断（100％）,普通x线胸片明确诊断2例（18％）,诊断准确率有明显差异（P=0．O001）。容积断层成像优质图像为10例,占总数的90．91％;良好1例,差为0例。11例x片中优秀7例,占总数的63．63％,其中良好3例,差1例。两种图像优秀率比较差异有统计学意义（P=0．0001）。结论：x线断层容积成像技术对肺动脉畸形的图像优秀率和诊断准确率均高于x线平片,对病变的显示更加清晰、立体,提高诊断准确率和客观性,具有重要的临床诊断价值。     

Computed tomography and magnetic resonance imaging in the diagnosis of accessory nasal sinuses, upper jaw and nasal cavity tumors

Radiation studies, including computed tomography (CT) and magnetic resonance imaging (MRI), revealed that these techniques can accurately determine the site of a tumor, the borders of its spread to the adjacent anatomic structures. They also revealed the features of CT in detecting osseous structural destruction and the advantage of MRI in visualizing the soft tissue component of a neoplasm and in distinguishing the degree of contrast of tumor tissue and concurrent secondary inflammation. The accuracy of CT and MRI for small tumors is 45-80 and 29% higher than that of X-ray study and traditional tomography, respectively. The potentialities of all radiation diagnostic techniques for over 3.0-cm tumors are equal.     

Ultrasound Guided Optoacoustic Tomography in Assessment of Tumor Margins for Lumpectomies

PURPOSE: To determine the accuracy of a handheld ultrasound-guided optoacoustic tomography (US-OT) probe developed for human deep-tissue imaging in ex vivo assessment of tumor margins postlumpectomy. METHODS: A custom-built two-dimensional (2D) US-OT–handheld probe was used to scan 15 lumpectomy breast specimens. Optoacoustic signals acquired at multiple wavelengths between 700 and 1100 nm were reconstructed using model linear algorithm, followed by spectral unmixing for lipid and deoxyhemoglobin (Hb). Distribution maps of lipid and Hb on the anterior, posterior, superior, inferior, medial, and lateral margins of the specimens were inspected for margin involvement, and results were correlated with histopathologic findings. The agreement in tumor margin assessment between US-OT and histopathology was determined using the Bland–Altman plot. Accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of margin assessment using US-OT were calculated. RESULTS: Ninety margins (6 × 15 specimens) were assessed. The US-OT probe resolved blood vessels and lipid up to a depth of 6 mm. Negative and positive margins were discriminated by marked differences in the distribution patterns of lipid and Hb. US-OT assessments were concordant with histopathologic findings in 87 of 89 margins assessed (one margin was uninterpretable and excluded), with diagnostic accuracy of 97.9% (kappa = 0.79). The sensitivity, specificity, PPV, and NPV were 100% (4/4), 97.6% (83/85), 66.7% (4/6), and 100% (83/83), respectively. CONCLUSION: US-OT was capable of providing distribution maps of lipid and Hb in lumpectomy specimens that predicted tumor margins with high sensitivity and specificity, making it a potential tool for intraoperative tumor margin assessment.     

64层螺旋CT脑血管造影在颅内动脉瘤诊断中的应用

目的:探讨64层螺旋CT血管造影(CTA)对颅内动脉瘤的诊断价值。方法:回顾性分析54例临床怀疑为颅内动脉瘤,并同时行64层CTA和DSA检查的病例,其中47例疑诊动脉瘤患者行动脉瘤夹闭手术,将MSCTA,DSA与手术结果对照。结果:54患者中经MSCTA检出57个动脉瘤,DSA检出55个动脉瘤,另7例MSCTA和DSA均未检出动脉瘤,余47例接受手术并检出58个动脉瘤。64层CTA发现动脉瘤的敏感性为96.6%,特异性为87.5%,准确性为96.5%,阳性预测值为98.2,阴性预测值为77.7。MIP和VR技术对动脉瘤的形态、分支血管、血栓和钙化方面的显示优于DSA。结论:64层CTA诊断颅内动脉瘤具有较好的异性、敏感性及三维显示能力,具有较高的临床应用价值。。     

A Multi-Branch Convolutional Neural Network for Screening and Staging of Diabetic Retinopathy Based on Wide-Field Optical Coherence Tomography Angiography

BackgroundDiabetic retinopathy (DR) is one of the major causes of blindness in adults suffering from diabetes. With the development of wide-field optical coherence tomography angiography (WF-OCTA), it is to become a gold standard for diagnosing DR. The demand for automated DR diagnosis system based on OCTA images have been fostered due to large diabetic population and pervasiveness of retinopathy cases.Materials and methodsIn this study, 288 diabetic patients and 97 healthy people were imaged by the swept-source optical coherence tomography (SS-OCT) with 12 mm × 12 mm single scan centered on the fovea. A multi-branch convolutional neural network (CNN) was proposed to classify WF-OCTA images into four grades: no DR, mild non-proliferative diabetic retinopathy (NPDR), moderate to severe NPDR, and proliferative diabetic retinopathy (PDR).ResultsThe proposed model achieved a classification accuracy of 96.11%, sensitivity of 98.08% and specificity of 89.43% in detecting DR. The accuracy of the model for DR staging is 90.56%, which is higher than that of other mainstream convolution neural network models.ConclusionThis technology enables early diagnosis and objective tracking of disease progression, which may be useful for optimal treatment to reduce vision loss.     

Computed tomography-guided fine needle aspiration biopsy of deep-seated lesions. A four-year experience

With the increased sophistication of radiologic imaging techniques, the sensitivity of detecting nonpalpable, deep-seated lesions has greatly improved. Coupling these techniques with fine needle aspiration biopsy (FNAB) provides a cost-effective, minimum-risk, highly sensitive and specific method of diagnostically evaluating the lesions. Over a four-year period (1985-1989) a total of 2,229 FNABs were performed at Loyola University Medical Center, Chicago; 539 of these biopsies were computed tomographically guided. The geographic computed tomographic biopsy sites were: thorax, 267 (49.54%); abdomen, 175 (32.47%); and retroperitoneum, 97 (18%). Four hundred eighty FNAB cases were diagnostic, with subsequent histologic follow-up in 284 (58%) cases. Fifty-nine (10.9%) FNABs were unsatisfactory; of them, 31 had subsequent diagnostic histology, and 9 remained unsatisfactory. A good correlation between FNAB and histology was observed, with an overall sensitivity of 93.2%, specificity of 98.8%, false-negative rate of 6.8% and false-positive rate of 1.2%. Diagnostic pitfalls and biopsy adequacy in computed tomographically guided FNABs are discussed.     

Assessment of Double Outlet Right Ventricle Associated with Multiple Malformations in Pediatric Patients Using Retrospective ECG-Gated Dual-Source Computed Tomography

Purpose

To evaluate the feasibility and diagnostic accuracy of retrospective electrocardiographically (ECG)-gated dual-source computed tomography (DSCT) for the assessment of double outlet right ventricle (DORV) and associated multiple malformations in pediatric patients.

Materials and Methods

Forty-seven patients <10 years of age with DORV underwent retrospective ECG-gated DSCT. The location of the ventricular septal defect (VSD), alignment of the two great arteries, and associated malformations were assessed. The feasibility of retrospective ECG-gated DSCT in pediatric patients was assessed, the image quality of DSCT and the agreement of the diagnosis of associated malformations between DSCT and transthoracic echocardiography (TTE) were evaluated, the diagnostic accuracies of DSCT and TTE were referred to surgical results, and the effective doses were calculated.

Results

Apart from DORV, 109 associated malformations were confirmed postoperatively. There was excellent agreement (κ = 0.90) for the diagnosis of associated malformations between DSCT and TTE. However, DSCT was superior to TTE in demonstrating paracardiac anomalies (sensitivity, coronary artery anomalies: 100% vs. 80.00%, anomalies of great vessels: 100% vs. 88.57%, separate thoracic and abdominal anomalies: 100% vs. 76.92%, respectively). Combined with TTE, DSCT can achieve excellent diagnostic performance in intracardiac anomalies (sensitivity, 91.30% vs. 100%). The mean image quality score was 3.70 ± 0.46 (κ = 0.76). The estimated mean effective dose was < 1 mSv (0.88 ± 0.34 mSv).

Conclusions

Retrospective ECG-gated DSCT is a better diagnostic tool than TTE for pediatric patients with complex congenital heart disease such as DORV. Combined with TTE, it may reduce or even obviate the use of invasive cardiac catheterization, and thus expose the patients to a much lower radiation dose.     

Sensitivity of Hyperdense Basilar Artery Sign on Non-Enhanced Computed Tomography

Purpose

The hyperdense basilar artery sign (HBAS) is an indicator of vessel occlusion on non contrast-enhanced computer tomography (NECT) in acute stroke patients. Since basilar artery occlusion (BAO) is associated with a high mortality and morbidity, its early detection is of great clinical value. We sought to analyze the influence of density measurement as well as a normalized ratio of Hounsfield unit/hematocrit (HU/Hct) ratio on the detection of BAO on NECT in patients with suspected BAO.

Materials and Methods

102 patients with clinically suspected BAO were examined with NECT followed immediately by Multidetector computed tomography Angiography. Two observers independently analyzed the images regarding the presence or absence of HBAS on NECT and performed HU measurements in the basilar artery. Receiver operating characteristic curve analysis was performed to determine the optimal density threshold for BAO using attenuation measurements or HU/Hct ratio.

Results

Sensitivity of visual detection of the HBAS on NECT was relatively low 81% (95%-CI, 54–95%) while specificity was high 91% (95%-CI, 82–96%). The highest sensitivity was achieved by the combination of visual assessment and additional quantitative attenuation measurements applying a cut-off value of 46.5 HU with 94% sensitivity and 81% specificity for BAO. A HU/Hct ratio >1.32 revealed sensitivity of 88% (95%-CI, 60–98%) and specificity of 84% (95%-CI, 74–90%).

Conclusion

In patients with clinically suspected acute BAO the combination of visual assessment and additional attenuation measurement with a cut-off value of 46.5 HU is a reliable approach with high sensitivity in the detection of BAO on NECT.     

Diagnostic Accuracy of Computed Tomography for Chronic Thromboembolic Pulmonary Hypertension: A Systematic Review and Meta-Analysis

This study aimed to determine the diagnostic accuracy of computed tomography imaging for the diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH). Additionally, the effect of test and study characteristics was explored. Studies published between 1990 and 2015 identified by PubMed, OVID search and citation tracking were examined. Of the 613 citations, 11 articles (n=712) met the inclusion criteria. The patient-based analysis demonstrated a pooled sensitivity of 76% (95% confidence interval [CI]: 69% to 82%), and a pooled specificity of 96% (95%CI: 93% to 98%). This resulted in a pooled diagnostic odds ratio (DOR) of 191 (95%CI: 75 to 486). The vessel-based analyses were divided into 3 levels: total arteries、main+ lobar arteries and segmental arteries. The pooled sensitivity were 88% (95%CI: 87% to 90%)、95% (95%CI: 92% to 97%) and 88% (95%CI: 87% to 90%), respectively, with a pooled specificity of 90% (95%CI: 88% to 91%)、96% (95%CI: 94% to 97%) and 89% (95% CI: 87% to 91%). This resulted in a pooled diagnostic odds ratio of 76 (95%CI: 23 to 254),751 (95%CI: 57 to 9905) and 189 (95%CI: 21 to 1072), respectively. In conclusion, CT is a favorable method to rule in CTEPH and to rule out pulmonary endarterectomy (PEA) patients for proximal branches. Furthermore, dual-energy and 320-slices CT can increase the sensitivity for subsegmental arterials, which are promising imaging techniques for balloon pulmonary angioplasty (BPA) approach. In the near future, CT could position itself as the key for screening consideration and for surgical and interventional operability.