INCREMENTAL DYNAMIC COMPUTER TOMOGRAPHY IN SURGICAL TREATMENT OF PATIENTS WITH SOLITARY PULMONARY NODULES

Objective The purpose of this study is to appraise the value of incremental dynamic enhanced computed tomography in surgical treatment of patients with solitary pulmonary nodules(SPNs).Methods The data of 42 cases with solitary pulmonary nodules who underwent surgical treatment from May 2002 to June 2003 in our hospital were collected to find the relationship between preoperative dynamic enhanced CT image and postoperative pathology.Result All bronchogenic carcinoma showed significant enhancement after intravenous 100 mL iodinated contrast material.The average degree of enhancement of bronchogenic carcinoma was significantly different from that of tuberculoma and other benign lesions.Conclusion Dynamic enhanced computed tomography is very valuable in distinguishing between malignant nodules and benign ones.Emphasis should be paid to lymph nodes in the dynamic enhanced computed tomography,which is useful both to the diagnosis of SPN and for surgical treatment.

Role of the texture features of images in the diagnosis of solitary pulmonary nodules in different sizes

Objective： To explore the role of the texture features of images in the diagnosis of solitary pulmonary nodules （SPNs） in different sizes. Materials and methods： A total of 379 patients with pathologically confirmed SPNs were enrolled in this study. They were divided into three groups based on the SPN sizes： ≤10, 11-20, and 〉20 mm. Their texture features were segmented and extracted. The differences in the image features between benign and malignant SPNs were compared. The SPNs in these three groups were determined and analyzed with the texture features of images. Results： These 379 SPNs were successfully segmented using the 2D Otsu threshold method and the self-adaptive threshold segmentation method. The texture features of these SPNs were obtained using the method of grey level co-occurrence matrix （GLCM）. Of these 379 patients, 120 had benign SPNs and 259 had malignant SPNs. The entropy, contrast, energy, homogeneity, and correlation were 3.5597±0.6470, 0.5384±0.2561, 0.1921±0.1256, 0.8281±0.0604, and 0.8748±0.0740 in the benign SPNs and 3.8007±0.6235, 0.6088±0.2961, 0.1673±0.1070, 0.7980±0.0555, and 0.8550±0.0869 in the malignant SPNs （all P〈0.05）. The sensitivity, specificity, and accuracy of the texture features of images were 83.3%, 90.0%, and 86.8%, respectively, for SPNs sized 〈10 mm, and were 86.6%, 88.2%, and 87.1%, respectively, for SPNs sized 11-20 mm and 94.7%, 91.8%, and 93.9%, respectively, for SPNs sized 〉20 mm. Conclusions： The entropy and contrast of malignant pulmonary nodules have been demonstrated to be higher in comparison to those of benign pulmonary nodules, while the energy, homogeneity correlation of malignant pulmonary nodules are lower than those of benign pulmonary nodules. The texture features of images can reflect the tissue features and have high sensitivity, specificity, and accuracy in differentiating SPNs. The sensitivity and accuracy increase for larger SPNs.

Comparison of three mathematical prediction models in patients with a solitary pulmonary nodule

Background： Effective methods for managing patients with solitary pulmonary nodules（SPNs） depend critically on the predictive probability of malignancy.Methods： Between July 2009 and June 2011, data on gender, age, cancer history, tumor familial history, smoking status, tumor location, nodule size, spiculation, calcification, the tumor border, and the final pathological diagnosis were collected retrospectively from 154 surgical patients with an SPN measuring 3-30 mm. Each final diagnosis was compared with the probability calculated by three predicted models—the Mayo, VA, and Peking University（PU） models. The accuracy of each model was assessed using area under the receiver operating characteristics（ROC） and calibration curves.Results： The area under the ROC curve of the PU model [0.800; 95% confidence interval（CI）： 0.708-0.891] was higher than that of the Mayo model（0.753; 95% CI： 0.650-0.857） or VA model（0.728; 95% CI： 0.623-0.833）; however, this finding was not statistically significant. To varying degrees, calibration curves showed that all three models overestimated malignancy.Conclusions： The three predicted models have similar accuracy for prediction of SPN malignancy, although the accuracy is not sufficient. For Chinese patients, the PU model may has greater predictive power.Background： Here, we introduced our short experience on the application of a new CUSA Excel ultrasonic aspiration system, which was provided by Integra Lifesciences corporation, in skull base meningiomas resection.Methods： Ten patients with anterior, middle skull base and sphenoid ridge meningioma were operated using the CUSA Excel ultrasonic aspiration system at the Neurosurgery Department of Shanghai Huashan Hospital from August 2014 to October 2014. There were six male and four female patients, aged from 38 to 61 years old（the mean age was 48.5 years old）. Five cases with tumor located at anterior skull base, three cases with tumor on middle skull base, and two cases with tumor on sphenoid ridge.Results： All the patents received total resection of meningiomas with the help of this new tool, and the critical brain vessels and nerves were preserved during operations. All the patients recovered well after operation.Conclusions： This new CUSA Excel ultrasonic aspiration system has the advantage of preserving vital brain arteries and cranial nerves during skull base meningioma resection, which is very important for skull base tumor operations. This key step would ensure a well prognosis for patients. We hope the neurosurgeons would benefit from this kind of technique.Background： The purposes of this study were to explore the effects of high mobility group protein box 1（HMGB1） gene on the growth, proliferation, apoptosis, invasion, and metastasis of glioma cells, with an attempt to provide potential therapeutic targets for the treatment of glioma. Methods： The expressions of HMGB1 in glioma cells（U251, U-87 MG and LN-18） and one control cell line（SVG p12） were detected by real time PCR and Western blotting, respectively. Then, the effects of HMGB1 on the biological behaviors of glioma cells were detected： the expression of HMGB1 in human glioma cell lines U251 and U-87 MG were suppressed using RNAi technique, then the influences of HMGB1 on the viability, cycle, apoptosis, and invasion abilities of U251 and U-87 MG cells were analyzed using in a Transwell invasion chamber. Also, the effects of HMGB1 on the expressions of cyclin D1, Bax, Bcl-2, and MMP 9 were detected. Results： As shown by real-time PCR and Western blotting, the expression of HMGB1 significantly increased in glioma cells（U251, U-87 MG, and LN-18） in comparison with the control cell line（SVG p12）; the vitality, proliferation and invasive capabilities of U251 and U-87 MG cells in the HMGB1 siR NA-transfected group were significantly lower than those in the blank control group and negative control（NC） siR NA group（P〈0.05） but showed no significant difference between the blank control group and NC siR NA group. The percentage of apoptotic U251 and U-87 MG cells was significantly higher in the HMGB1 siR NA-transfected group than in the blank control group and NC siR NA group（P〈0.05） but was similar between the latter two groups. The HMGB1 siR NA-transfected group had significantly lower expression levels of Cyclin D1, Bcl-2, and MMP-9 protein in U251 and U-87 MG cells and significantly higher expression of Bax protein than in the blank control group and NC siR NA group（P〈0.05）; the expression profiles of cyclin D1, Bax, Bcl-2, and MMP 9 showed no significant change in both blank control group and NC siR NA group. Conclusions： HMGB1 gene may promote the proliferation and migration of glioma cells and suppress its effects of apoptosis. Inhibition of the expression of HMGB1 gene can suppress the proliferation and migration of glioma cells and promote their apoptosis. Our observations provided a new target for intervention and treatment of glioma.

Dynamic contrast-enhanced MRI versus ^(18)F-FDG PET/CT: Which is better in differentiation between malignant and benign solitary pulmonary nodules?

Objective： To prospectively compare the discriminative capacity of dynamic contrast enhanced-magnetic resonance imaging（DCE-MRI） with that of^18F-fluorodeoxyglucose（^18F-FDG） positron emission tomography/computed tomography（PET/CT） in the differentiation of malignant and benign solitary pulmonary nodules（SPNs）.Methods： Forty-nine patients with SPNs were included in this prospective study. Thirty-two of the patients had malignant SPNs, while the other 17 had benign SPNs. All these patients underwent DCE-MRI and ^18F-FDG PET/CT examinations. The quantitative MRI pharmacokinetic parameters, including the trans-endothelial transfer constant（K^trans）, redistribution rate constant（Kep）, and fractional volume（Ve）, were calculated using the Extended-Tofts Linear two-compartment model. The ^18F-FDG PET/CT parameter, maximum standardized uptake value（SUV（max））, was also measured. Spearman＇s correlations were calculated between the MRI pharmacokinetic parameters and the SUV（max） of each SPN. These parameters were statistically compared between the malignant and benign nodules. Receiver operating characteristic（ROC） analyses were used to compare the diagnostic capability between the DCE-MRI and ^18F-FDG PET/CT indexes.Results： Positive correlations were found between K^trans and SUV（max）, and between K（ep） and SUV（max）（P〈0.05）.There were significant differences between the malignant and benign nodules in terms of the K^trans, K（ep） and SUV（max） values（P〈0.05）. The areas under the ROC curve（AUC） of K^trans） K（ep） and SUV（max） between the malignant and benign nodules were 0.909, 0.838 and 0.759, respectively. The sensitivity and specificity in differentiating malignant from benign SPNs were 90.6% and 82.4% for K^trans; 87.5% and 76.5% for K（ep）; and 75.0% and 70.6%for SUV（max）, respectively. The sensitivity and specificity of K^trans and K（ep） were higher than those of SUV（max）, but there was no significant difference between them（P〉0.05）.Conclusions： DCE-MRI can be used to differentiate between benign and malignant SPNs and has the advantage of being radiation free.

Correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size

Objective： To evaluate the correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size. Methods： Sixty-eight patients with malignant solitary pulmonary nodules （SPNs） （diameter 〈4 cm） underwent multi-location dynamic contrast material-enhanced （nonionic contrast material was administrated via the antecubitai vein at a rate of 4mL/s by using an autoinjector, 4×5 mm or 4×2.5 mm scanning mode with stable table were performed）. Precontrast and postcontrast attenuation on every scan was recorded. Blood flow （BF）, peak, height （PHSPN）, ratio of peak height of the SPN to that of the aorta （SPN-to-A ratio） and mean transit time （MTT） were calculated. The correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size were assessed by means of linear regression analysis. Results： No significant correlations were found between the tumor size and each of the peak height （PHSPN） （35.79±10.76 Hu）, ratio of peak height of the SPN to that of the aorta （SPN-to-A ratio）, （14.27%±4.37） and blood flow （BF） （30.18 mL/min/100 g±9.58） （r=0.180, P=0.142〉0.05; r=0.205, P=0.093〉0.05; r=0.008, P=0.947〉0.05）. Conclusion： No significant correlations were found between the tumor size and each of the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules.

Blood flow patterns of solitary pulmonary nodules with enhancement

Objective： To evaluate the efficacy of dynamic multi-slice spiral computed tomography （MSCT） for providing quantitative information about blood flow patterns of solitary pulmonary nodules （SPNs）. Methods： Seventy-eight patients with SPNs （diameter 〈 4 cm; 68 malignant; 10 active inflammatory） were underwent multi-location dynamic contrast material-enhanced serial CT （nonionic contrast material was administrated via the antecubital vein at a rate of 4 mLJs by using an autoinjector, 4 × 5 mm or 4 × 2.5 mm transverse scanning mode with stable table were performed）. Sixteen series CT scans （16 scans each for the first and second series and one scan each for the rest series） were obtained during 9 min scanning period. Precontrast and postcontrast attenuation on every scan was recorded. Perfusion, peak height and ratio of peak height of the SPN to that of the aorta were calculated. Perfusion was calculated from the maximum gradient of the time-attenuation curve and the peak height of the aorta. Results： No statistically significant difference in the peak height was found between malignant （35.79 ± 10.76 Hu） and active inflammatory （39.76 ± 4.59 Hu） （t = 1.148, P = 0.255 〉 0.05）. SPN-to-aorta ratio （14.27% ± 4.37） and perfusion value （30.18 mL/min/100 g ± 9.58） in malignant SPNs were significantly lower than those of active inflammatory （18.51% ± 2.71, 63.44 mL/min/100 g ± 43.87） （t = 2.978, P = 0.004 〈 0.05; t = 5.590, P 〈 0.0001）. Conclusion： The quantitative information about blood flow patterns of malignant and active inflammatory SPNs is different. SPN-to-aorta ratio and perfusion value are helpful in differentiating malignant nodules from active inflammatory.

BLOOD FLOW PATTERN AND QUANTITATIVE STUDY IN SOLITARY PULMONARY NODULES WITH DYNAMIC CONTRAST-ENHANCED MRI

Objective To evaluate the efficacy of contrast enhanced dynamic MRI in differentiating solitary pulmonary nodules（SPNs）. Methods Eighty-three patients with SPNs undertaken contrast enhanced dynamic MRI. Time-signal intensity curve （T-SI Curve） was made. Peak height （PH） , steepest slope （SS）, maximum enhancement （ Emax ） and the enhancement rates of signal intensity were recorded at the frst （ E1 ）, second （ E2 ）, third （ E3 ） , fourth （ E4 ） , fifth （E5）, and sixth （ E6 ） minute after injection. Results Malignant nodules and inflammatory nodules enhanced significantly higher than benign nodules, and malignant nodules and inflammatory nodules showed obviously higher PH, SS, Emax, El-E6 values than benign nodules （ P 〈 0. 01 ）. There were no sig- nificant differences in PH, SS, Emax, E1-E6 values between malignant nodules and inflammatory nodules （P 〉 0. 05）. Conclusion Contrast enhanced dynamic MR imaging can provide SPNs＇ hemodynamic information and is helpful in differentiating SPNs.

Decision-tree analysis for cost-effective management of solitary pulmonary nodules in China

AIM: To analyze the cost-effectiveness of the diagnosis of solitary pulmonary nodule(SPN) in China. METHODS: Decision analysis models were constructed to assess the cost-effectiveness of four strategies for the management of SPN: computed tomography(CT) alone, CT plus CT-guided automated cutting needle biopsy(ACNB), CT plus positron emission tomography/computed tomography(PET/CT), CT plus diffusionweighted magnetic resonance imaging(DWI) plus PET/CT. RESULTS: The prevalence of lung cancer among SPN discovered in the clinical setting was approximately 50%. The CT plus ACNB strategy had higher diagnostic accuracies(87% vs 81%), with a cost saving of $1945 RMB per patient, and reducing unnecessary thoracotomy by 16.5%; this was associated with a 4.5% missed diagnosis rate. CT plus DWI plus PET/CT strategy also had higher accuracies(95% vs 81%), with a cost saving of $590 RMB per patient, and reducing unneces-sary thoracotomy by 13.5%; this was accompanied by 0.3% missed diagnosis rate. CT plus PET strategy is cost effective at a prevalence rate of 0-34%, but there was a larger prevalence range of lung cancer for CT plus ACNB strategy(from 0 to 0.6) and CT plus DWI plus PET/CT strategy(from 0 to 0.64). CONCLUSION: CT plus DWI plus PET/CT strategy was cost-effective, and had a higher accuracy accompanied by a lower missed diagnosis rate than CT plus ACNB strategy.

Analysis of 96 cases of solitary pulmonary nodule diagnosed by MSCT

Objective:The aim of this study was to explore the diagnostic value of multi-slice computer tomography(MSCT) in solitary pulmonary nodule(SPN).Methods:Contrastive analysis of the differences of CT signs between benign and malignant SPN.Results:The typical sign of pleural indentation was a reliable sign for lung cancers.Vacuole sign suggested lung cancer highly.Blood vessels cluster involving the vein alone had big opportunity to lung cancer.Type I tumor-bronchial relation was the most common relation in lung cancers.Type V tumor–bronchial relation was the most common relation in benign SPN.Conclusion:MSCT had a very high diagnostic value in SPN.

Bronchoscopic Diagnosis of Solitary Pulmonary Nodules with the Use of NIR Spectroscopy

Background: Recently, SPN has become a much more frequently encountered issue in bronchology. Efficient and reliable guidance method for SPN morphological proof is highly needed. Objectives: The aim of study was to compare the diagnostic values of NIR (near infrared) spectroscopy with EBUS for SPN diagnostic. Fluoroscopic guidance with TBB and needle biopsy were done in all patients. Methods: In our study, we used two types of monitoring systems. Fluoroscopic guidance was combined with either a radial EBUS or a NIR spectroscopy probe for tissue confirmation. 139 male and 71 female patients, having a medial age of 68 years with CT/PET findings of metabolically active SPN were examined between 2/2010 and 2/2013. We designed an instrument for measurement of the penetration of the NIR through lung tissue. Indicating and source fibers were navigated towards the SPN. An EBUS radial probe was used, during fluoroscopic navigation. Results: The statistical analysis of the results obtained showed a comparative specificity and sensitivity of the NIR spectroscopy, with radial EBUS. Conclusions: NIR spectroscopy produced similar efficacies as the radial EBUS. However, the number of positive biopsies was more dependent upon the ability to direct the confirmatory device to the SPN during fluoroscopic guidance than on the type of the device.

Enhanced characterization of solid solitary pulmonary nodules with Bayesian analysis-based computer-aided diagnosis

The aim of this study was to prospectively assess the accuracy gain of Bayesian analysis-based computeraided diagnosis(CAD) vs human judgment alone in characterizing solitary pulmonary nodules(SPNs) at computed tomography(CT). The study included 100 randomly selected SPNs with a definitive diagnosis. Nodule features at first and follow-up CT scans as well as clinical data were evaluated individually on a 1 to 5 points risk chart by 7 radiologists, firstly blinded then aware of Bayesian Inference Malignancy Calculator(BIMC) model predictions. Raters' predictions were evaluated by means of receiver operating characteristic(ROC) curve analysis and decision analysis. Overall ROC area under the curve was 0.758 before and 0.803 after the disclosure of CAD predictions(P = 0.003). A net gain in diagnostic accuracy was found in 6 out of 7 readers. Mean risk class of benign nodules dropped from 2.48 to 2.29, while mean risk class of malignancies rose from 3.66 to 3.92. Awareness of CAD predictions also determined a significant drop on mean indeterminate SPNs(15 vs 23.86 SPNs) and raised the mean number of correct and confident diagnoses(mean 39.57 vs 25.71 SPNs). This study provides evidence supporting the integration of the Bayesian analysis-based BIMC model in SPN characterization.

Comparison of Various Parameters of DWI in Distinguishing Solitary Pulmonary Nodules

In order to prospectively assess various parameters of diffusion weighted imaging (DWI)in differential diagnosis of benign and malignant solitary pulmonary nodules (SPNs),58 patients (40 men and 18 women,and mean age of 48.1±10.4years old) with SPNs undergoing conventional MR,DWI using b=500s/mm^2 on a 1.5T MR scanner, were studied.Various DWI parameters [apparent diffusion coefficient (ADC),lesion-to-spinal cord signal intensity ratio (LSR),signal intensity (SI)score] were calculated and compared between malignant and benign SPNs groups.A receiver operating characteristic (ROC)curve analysis was employed to compare the diagnostic capabilities of all the parameters for discrimination between benign and malignant SPNs.The results showed that there were 42 malignant and 16 benign SPNs.The ADC was significantly,lower in malignant SPNs (1.40±0.44)×10^-3mm^2/s than in benign SPNs (1.81±0.58)×10^-3mm^2/ s.The LSR and SI scores were significantly increased in malignant SPNs (0.90±0.37 and 2.8±1.2)as compared with those in benign SPNs (0.68±0.39 and 2.2±1.2).The area under the ROC curves (AUC)of all parameters was not significantly different between malignant SPNs and benign SPNs.It was suggested that as three reported parameters for DWI,ADC,LSR and SI scores are all feasible for discrimination of malignant and benign SPNs.The three parameters have equal diagnostic performance.

Differentiation of Benign and Malignant Solitary Pulmonary Nodule: Literature Review

The solitary pulmonary nodule (SPN) is frequently seen on chest radiographs and computed tomography (CT), usually the identification is accidental. The overall prevalence of malignancy is relatively low but identification of malignancy of nodule is of prime importance. There are different characters of nodules indicating malignancy, and also the exposure of person to risk factors increases the chances of malignancy of nodule. Chances of malignancy rise with increasing size, the irregular, lobulated border of the nodules is highly associated with higher probability of malignancy and nodules with pure ground grass appearance have higher probability of malignancy, irregularly marginated nodule displaying a corona radiata sign indicating neoplastic infiltration with distortion of neighbouring tissue is almost certainly a malignant nodule. Stippled, punctuate, and eccentric calcifications are suggestive of malignancy. There are 20% - 75% of chances of malignancy if nodule is appeared with ground-glass opacity. Malignant nodules have higher growth rate as compared with benign nodules, malignant nodules usually have doubling time (DT) of 30 - 400 days while DT of more than 450 days is sign of benignity whereas doubling time less than 30 days is usually acute infectious process. The presence of fat within nodule is sign of benignity. Increasing density of the nodule is suggestive of malignancy and requires shorter follow up. Besides the nodule evaluation the chances of malignancy can also be evaluated through the exposure of patient to risk factors like age, current and past smoking status and history of extra thoracic malignancy. The management depends upon various factors mainly three strategies are applied for management including careful observation of nodule, use of diagnostic techniques like CT FNA, PET, and broncoscopy and surgery.

The effect of single-operation-hole thoracoscopic surgery on elderly solitary pulmonary nodules and its effects on lung function and prognosis

Objective:To investigate the effect of single-operation-hole thoracoscopic surgery on elderly solitary pulmonary nodules and its effects on lung function and prognosis.Methods:64 patients with solitary pulmonary nodules admitted to our hospital were selected. According to the different surgical treatment methods, they were divided into the study group and the control group, each group with 32 cases. The study group was treated with single-operation-hole thoracoscopic pulmonary nodule resection, and the control group was treated with conventional multi-operation-holes thoracoscopic pulmonary nodule resection. The clinical efficacy of the two groups was compared. Results: The postoperative drainage time, intraoperative blood loss, hospitalization time, postoperative drainage volume and hospitalization cost of the study group were significantly better than those of the control group (P<0.05), and there were no significant differences between the two groups in terms of the duration of operation and the incidence of adverse reactions (such as postoperative pulmonary atelectasis and pulmonary infection) (P>0.05). There was no difference in lung function between the two groups before operation (P>0.05). Compared with the control group, the lung function indexes of the postoperative study group were significantly improved (P<0.05). There was no difference in the overall survival rate and tumor-free survival rate of the two groups after operation for half a year (P>0.05). The VAS scores of the study group were significantly lower than those of the control group on the 1st and 3rd day after operation (P<0.05). There was no difference in the quality of life between the two groups before treatment (P>0.05), but the overall health status, physiological feature, physiological function, physical pain and energy of the patients in the study group after treatment were significantly higher than those in the control group (P<0.05), but there was no significant difference in social function, emotional function and mental health (P>0.05).Conclusions: Single-operation-hole thoracoscopic surgery is effective in the treatment of elderly solitary pulmonary nodules. It can not only accelerate the recovery of patients but also improve their lung function, without affecting the prognosis of patients, which can improve their quality of life. It is worthy of clinical application, but should strictly control the indications for surgery.

Neural network-based computer-aided diagnosis in distinguishing malignant from benign solitary pulmonary nodules by computed tomography

Background Computer-aided diagnosis （CAD） of lung cancer is the subject of many current researches. Statistical methods and artificial neural networks have been applied to more quantitatively characterize solitary pulmonary nodules （SPNs）. In this study, we developed a CAD scheme based on an artificial neural network to distinguish malignant from benign SPNs on thin-section computed tomography （CT） images, and investigated how the CAD scheme can help radiologists with different levels of experience make diagnostic decisions. Methods Two hundred thin-section CT images of SPNs with proven diagnoses （135 small peripheral lung cancers and 65 benign nodules） were analyzed. Three clinical features and nine CT signs of each case were studied by radiologists, and the indices of qualitative diagnosis were quantified. One hundred and forty nodules were selected randomly to form training samples, on which the neural network model was built. The remaining 60 nodules, forming test samples, were presented to 9 radiologists with 3-20 years of clinical experience, accompanied by standard reference images. The radiologists were asked to determine whether a nodule was malignant or benign first without and then with CAD output. Diagnostic performance was evaluated by receiver operating characteristic （ROC） analysis. Results CAD outputs on test samples had higher agreement with pathological diagnoses （Kappa=0.841, P〈0.001）. Compared with diagnostic results without CAD output, the average area under the ROC curve with CAD output was 0.96 （P〈0.001） for junior radiologists, 0.94 （P=0.014） for secondary radiologists and 0.96 （P=0.221） for senior radiologists, respectively. The differences in diagnostic performance with CAD output among the three levels of radiologists were not statistically significant （P=0.584, 0.920 and 0.707, respectively）. Conclusions This CAD scheme based on an artificial neural network could improve diagnostic performance and assist radiologists in distinguishing malignant from benign SPNs on thin-section CT images.

A controlled study of positron-emission-tomography and positron-emission-tomography/computed tomography in differential diagnosis of solitary pulmonary nodules—report of 60 cases

The differential diagnosis of solitary pulmonary nodules （SPNs） remains a challenge. It is acknowledged that combining positron-emission tomography （PET） and computed tomography （CT） offers the most reliable noninvasive method for the diagnosis of SPNs. Since Townsend et al1 developed integrated PET/CT in 1999, this technique has increasingly been introduced into clinical practice. To date, nuclear medicine physicians have usually undertaken PET/CT diagnosis, but the question is surfacing as how to make full use of the information of CT image to improve the accuracy of SPN diagnosis. To answer this question, we performed a retrospective study on 60 patients with SPNs.

Diffusion-weighted magnetic resonance imaging with short T1 inversion recovery-echo planar imaging combined with dual-head coincidence single photon emission computed tomography for diagnosing solitary pulmonary nodule

Positron emission tomography （PET） using 18F-fluorodeoxyglucose （FDG） has not been widely used in China for expensive cost （$1200）. Dual-head coincidence single photon emission computed tomography （DHC-SPECT） can depict many of the lesions depicted with a PET scanner in the lungs, which is used in place of PET-CT for discriminating malignant from benign pulmonary nodules in many studies. However, DHC-SPECT has inevitable false-negative results because the sensitivity for small lesions less than 2.0 cm is limited, and has high false-positive rate for active inflammatory nodules. Furthermore,DHC-SPECT also has a considerably higher cost （$300 in China） than other imaging examination.

Phase II Clinical Study of Three-Dimensional Printed Coplanar Template Combined with CT-Guided Percutaneous Core Needle Biopsy of Pulmonary Nodules in Elderly Patients

Background: As the population age structure gradually ages, more and more elderly people were found to have pulmonary nodules during physical examinations. Most elderly people had underlying diseases such as heart, lung, brain and blood vessels and cannot tolerate surgery. Computed tomography (CT)-guided percutaneous core needle biopsy (CNB) was the first choice for pathological diagnosis and subsequent targeted drugs, immune drugs or ablation treatment. CT-guided percutaneous CNB requires clinicians with rich CNB experience to ensure high CNB accuracy, but it was easy to cause complications such as pneumothorax and hemorrhage. Three-dimensional (3D) printing coplanar template (PCT) combined with CT-guided percutaneous pulmonary CNB biopsy has been used in clinical practice, but there was no prospective, randomized controlled study. Methods: Elderly patients with lung nodules admitted to the Department of Oncology of our hospital from January 2019 to January 2023 were selected. A total of 225 elderly patients were screened, and 30 patients were included after screening. They were randomly divided into experimental group (Group A: 30 cases) and control group (Group B: 30 cases). Group A was given 3D-PCT combined with CT-guided percutaneous pulmonary CNB biopsy, Group B underwent CT-guided percutaneous pulmonary CNB. The primary outcome measure of this study was the accuracy of diagnostic CNB, and the secondary outcome measures were CNB time, number of CNB needles, number of pathological tissues and complications. Results: The diagnostic accuracy of group A and group B was 96.67% and 76.67%, respectively (P = 0.026). There were statistical differences between group A and group B in average CNB time (P = 0.001), number of CNB (1 vs more than 1, P = 0.029), and pathological tissue obtained by CNB (3 vs 1, P = 0.040). There was no statistical difference in the incidence of pneumothorax and hemorrhage between the two groups (P > 0.05). Conclusions: 3D-PCT combined with CT-guided percutaneous CNB can improve the puncture accuracy of elderly patients, shorten the puncture time, reduce the number of punctures, and increase the amount of puncture pathological tissue, without increasing pneumothorax and hemorrhage complications. We look forward to verifying this in a phase III randomized controlled clinical study. .

Receiver operating characteristic curve analysis for image quality in the detection of solitary pulmonary nodules on high resolution paper prints versus dry laser film

Along with the development of digital X-ray imaging technology, a new, economical and practicalpaper-based output system gradually emerged. To reduce cost, more and more radiologic institutions began to change from film copies to lower-priced paper prints for documenting radiologic findings.Therefore, laser paper printers are frequently used as an alternative to duplicating film though the use of printed images is not yet widespread. The aim of this study was to compare the practical value of high-resolution paper printer with dry film copies for detecting small solitary pulmonary nodules （SPNs）.

Dynamic enhanced multi-slice spiral CT in evaluation of blood flow patterns of solitary pulmonary nodules with enhancement

Objective To investigate the methods of dynamic enhanced multi-slice spiral CT in evaluation of blood flow patterns of solitary pulmonary nodules (SPNs) with enhancement. Methods Seventy-eight patients with SPNs (≤4 cm) with strong enhancement underwent dynamic multi-slice spiral CT (Marconi Mx8000) scan before and after contrast enhancement by injecting contrast material with a rate of 4 mL/s. For the 40 patients in protocol one, one scan was obtained every 2 seconds during 15--45 and 75--105 seconds after injection, while for the 38 patients in protocol two, one scan was obtained every 2 seconds during 11--41 and 71--101 seconds. For all the patients, one scan was obtained every 30 seconds during 2--9 minutes. The section thickness was 2.5 mm for lesions ≤3 cm and 5 mm for lesions >3 cm. Standard algorithm was used in the image reconstruction. Precontrast and postcontrast attenuation on every scan was recorded. The perfusion, peak height, ratio of peak height of the SPN to that of the aorta and mean transit time were calculated. Results The peak height, perfusion, ratio of peak height of the SPN to that of the aorta and mean transit time in malignant SPNs were 34.85 Hu±10.87 Hu, 30.37 ml/(min·100 g)±11.14 ml/(min·100 g), 13.78%± 3.96% , 14.19 s±6.19 s respectively in protocol one, while those in protocol two were 36.62 Hu±10.75 Hu, 30.01 ml/(min·100 g)±8.10 ml/(min·100 g), 14.70 %±4.71%, 13.91 s±4.82 s respectively. No statistically significant differences were found between the peak height (t= 0.673, P=0.503), perfusion (t= 0.152 , P=0.880), ratio of peak height of the SPN to that of the aorta (t= 0.861, P=0.393) and mean transit time (t= 0.199, P=0.843) in malignant SPNs measured in protocol one and those measured in protocol two. All mean transit time in protocol two (36/36) were obtained, but only part of them (25/32) were obtained in protocol one. Conclusion Dynamic enhanced multi-slice spiral CT is a non-invasive method for quantitative evaluation of blood flow patterns of SPNs with enhancement and scans beginning at 11 seconds after injection of contrast material is suggested.