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Los nódulos pulmonares pueden ser variados: sólidos, en vidrio esmerilado; granulo matosos o no granulomatosos; cavitados o no cavitado. Son un hallazgo frecuente en las imágenes de tórax cuando el paciente llega a la consulta. Según sus características y en concordancia con los antecedentes del paciente (historia clínica, exámen físico y resultados de laboratorio) nos orienta a las distintas etiologías: infeccioso, autoinmune u oncológico. Sin embargo, muchas veces es un gran desafío clínico. Se presenta el caso de una paciente joven sin antecedentes que consulta por tos de 3 meses de evolución. En TC de tórax se evidencia masa mediastinal izquierda que desplaza tráquea y nódulos pulmonares bilaterales cavitados. Luego de descartarse etiologías más probables por frecuencia para su edad y forma de manifestación clínica, se arriba al diagnóstico de Linfoma de Hodgkin clásico Esclero Nodular con compromiso extranodal. Enfermedad poco frecuente y en nuestro caso, modo de presentación atípica.
Lung nodules can vary in nature: solid, ground glass, granulomatous or non-granulo matous, cavitary or non-cavitary. They are a common finding in chest imaging when the patient comes to the consultation. According to their characteristics and the patient's history (medical history, physical examination, and laboratory results), they guide us towards different etiologies: infectious, autoimmune, or oncological. However, many times it is a great clinical challenge. We present the case of a young patient with no previous medical history who came to the consultation with a cough of 3 months of evolution. The chest CT showed left mediastinal mass displacing the trachea and bilateral cavitary lung nodules. After ruling out more probable etiologies based on frequency for the patient's age and clinical manifestation, the diagnosis was: classic nodular sclerosing Hodgkin lymphoma with extranodal in volvement. A very rare disease, and in our case, with an atypical form of presentation.
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Nódulos Pulmonares MúltiplosRESUMO
OBJECTIVES@#With the increasing detection rate of lung nodules, the qualitative problem of lung nodules has become one of the key clinical issues. This study aims to evaluate the value of combining dynamic contrast-enhanced (DCE) MRI based on time-resolved imaging with interleaved stochastic trajectories-volume interpolated breath hold examination (TWIST-VIBE) with T1 weighted free-breathing star-volumetric interpolated breath hold examination (T1WI star-VIBE) in identifying benign and malignant lung nodules.@*METHODS@#We retrospectively analyzed 79 adults with undetermined lung nodules before the operation. All nodules of patients included were classified into malignant nodules (n=58) and benign nodules (n=26) based on final diagnosis. The unenhanced T1WI-VIBE, the contrast-enhanced T1WI star-VIBE, and the DCE curve based on TWIST-VIBE were performed. The corresponding qualitative [wash-in time, wash-out time, time to peak (TTP), arrival time (AT), positive enhancement integral (PEI)] and quantitative parameters [volume transfer constant (Ktrans), interstitium-to-plasma rate constant (Kep), and fractional extracellular space volume (Ve)] were evaluated. Besides, the diagnostic efficacy (sensitivity and specificity) of enhanced CT and MRI were compared.@*RESULTS@#There were significant differences in unenhanced T1WI-VIBE hypo-intensity, and type of A, B, C DCE curve type between benign and malignant lung nodules (all P<0.001). Pulmonary malignant nodules had a shorter wash-out time than benign nodules (P=0.001), and the differences of the remaining parameters were not statistically significant (all P>0.05). After T1WI star-VIBE contrast-enhanced MRI, the image quality was further improved. Compared with enhanced CT scan, the sensitivity (82.76% vs 80.50%) and the specificity (69.23% vs 57.10%) based on MRI were higher than that of CT (both P<0.001).@*CONCLUSIONS@#T1WI star-VIBE and dynamic contrast-enhanced MRI based on TWIST-VIBE were helpful to improve the image resolution and provide more information for clinical differentiation between benign and malignant lung nodules.
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Adulto , Humanos , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Plasma , Tomografia Computadorizada por Raios X , PulmãoRESUMO
@#In recent years, with the improvement of CT resolution, the reduction of radiation dose, the popularization of lung cancer screening and the enhancement of people's health awareness, the detection rate of lung nodules is higher and higher. Due to the close relationship between lung nodules and lung cancer, more and more attention has been paid to them. Although patients with early and middle stage lung cancer receive complete resection, all postoperative patients are at risk of recurrence and metastasis. Adjuvant or neoadjuvant therapy can improve the survival and reduce the recurrence and metastasis. Therefore, the multidisciplinary team, as the best model, provides a standardized and individualized plan for the diagnosis and treatment of lung nodules and lung cancer patients. However, in the clinical practice, the work efficiency of the multidisciplinary team is not high, and the participation rate of patients is low; therefore the multidisciplinary doctor model with thoracic surgeons as the mainstay is a reasonable alternative.
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@#Objective To evaluate the effectiveness of the artificial intelligence-assisted diagnosis and treatment system in distinguishing benign and malignant lung nodules and the infiltration degree. Methods Clinical data of 87 patients with pulmonary nodules admitted to the First Affiliated Hospital of Xiamen University from January 2019 to August 2020 were retrospectively analyzed, including 33 males aged 55.1±10.4 years, and 54 females aged 54.5±14.1 years. A total of 90 nodules were included, which were divided into a malignant tumor group (n=80) and a benign lesion group (n=10), and the malignant tumor group was subdivided into an invasive adenocarcinoma group (n=60) and a non-invasive adenocarcinoma group (n=20). The malignant probability and doubling time of each group were compared and its ability to predict the benign and malignant nodules and the invasion degree was analyzed. Results Between the malignant tumor group and the benign lesion group, the malignant probability was significantly different, and the malignant probability could better distinguish malignant nodules and benign lesions (87.2%±9.1% vs. 28.8%±29.0%, P=0.000). The area under the curve (AUC) was 0.949. The maximum diameter of nodules in the benign lesion group was significantly longer than that in the malignant tumor group (1.270±0.481 cm vs. 0.990±0.361 cm, P=0.026); the doubling time of benign lesions was significantly longer than that of malignant nodules (1 083.600±258.180 d vs. 527.025±173.176 d, P=0.000), and the AUC was 0.975. The maximum diameter of the nodule in the invasive adenocarcinoma group was longer than that of the non-invasive adenocarcinoma group (1.350±0.355 cm vs. 0.863±0.271 cm, P=0.000), and there was no statistical difference in the probability of malignancy between the invasive adenocarcinoma group and the non-invasive adenocarcinoma group (89.7%±5.7% vs. 86.4%±9.9%, P=0.082). The AUC was 0.630. The doubling time of the invasive adenocarcinoma group was significantly shorter than that of the non-invasive adenocarcinoma group (392.200±138.050 d vs. 571.967±160.633 d, P=0.000), and the AUC was 0.829. Conclusion The malignant probability and doubling time of lung nodules calculated by the artificial intelligence-assisted diagnosis and treatment system can be used in the assessment of the preoperative benign and malignant lung nodules and the infiltration degree.
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The magnetic anchoring lung nodule positioning device is composed of a target magnet, an anchor magnet, a coaxial puncture needle and a puncture navigation template, through these, a new type of accurate positioning technology for small pulmonary nodules is derived. The device inserts the target magnet into the both sides nearby the lung nodule under the guidance of CT. Helped by the mutual attraction of the two target magnets, they can be fixed in the lung tissue, avoiding the movement in the lung, and accurately positioning the target lung nodule before surgery. In thoracoscopic surgery, the anchor magnet and the target magnet attract each other to achieve the purpose of positioning the target nodule. The device uses the characteristics of non-contact suction of magnetic materials biomedical engineering technology, eliminating the previous procedure of direct interaction with the positioning marks, finally achieves the target of precise positioning of lung nodules and rapid surgical removal.
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Humanos , Pulmão , Neoplasias Pulmonares , Fenômenos Magnéticos , Imãs , Nódulo Pulmonar Solitário , Cirurgia Torácica Vídeoassistida , Tomografia Computadorizada por Raios XRESUMO
Introducción: El nódulo pulmonar es un hallazgo generalmente incidental. Su detección ha aumentado observándose hasta en 13 por ciento de las tomografías. El diagnóstico diferencial plantea un desafío. Objetivo: Describir el caso de un paciente con nódulos pulmonares múltiples y su abordaje a partir de recomendaciones basadas en la evidencia. Caso clínico: Se presenta el caso de un paciente de 35 años con sintomatología inespecífica y nódulos pulmonares múltiples incidentales en estudios cervicotorácicos. Se analizaron etiologías posibles según datos clínicos, epidemiológicos, radiológicos y probabilidad de malignidad. Las recomendaciones basadas en la evidencia dirigieron el manejo. Dada la probabilidad intermedia de malignidad se indicó seguimiento escanográfico en 3 a 6 meses. Conclusiones: El caso presentado pretende reforzar destrezas clínicas en el manejo de esta entidad repercutiendo favorablemente en la morbimortalidad. Busca además impulsar el desarrollo de estrategias de tamizaje en poblaciones de riesgo(AU)
Introduction: The pulmonary nodule is a generally incidental finding. Its detection has increased, being observed in up to 13 percent of CT scans. Differential diagnosis poses a challenge. Objective: To describe the case of a patient with multiple pulmonary nodules and the approach to it based on evidence-based recommendations. Clinical case report: The case of a 35-year-old patient with nonspecific symptoms and incidental multiple pulmonary nodules in cervicothoracic studies is reported. Possible etiologies were analyzed according to clinical, epidemiological, radiological data and probability of malignancy. Evidence-based recommendations guided management. Given the intermediate probability of malignancy, a scan follow-up was indicated in 3 to 6 months. Conclusions: This case aims to reinforce clinical skills in the management of this entity, favourably impacting on morbidity and mortality. It also seeks to promote the development of screening strategies in populations at risk(AU)
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Humanos , Masculino , Adulto , Tomografia Computadorizada por Raios X/métodos , Nódulo Pulmonar Solitário/etiologia , Nódulo Pulmonar Solitário/diagnóstico por imagem , Achados Incidentais , Colômbia , Granuloma/diagnósticoRESUMO
@#Objective To introduce the application of mixed reality technique to the preoperative and intraoperative pulmonary nodules surgery. Methods One 49-year female patient with multiple nodules in both lobes of the lung who finally underwent uniportal thoracoscopic resection of superior segment of left lower lobe and wedge resection of left upper lobe was taken as an example. The Mimics medical image post-processing software was used to reconstruct the patient's lung image based on the DICOM data of the patient's chest CT image before the surgery. The three-dimensional reconstructed image data was imported into the HoloLens glasses, and the preoperative discussions were conducted with the assistance of mixed reality technology to formulate the surgical methods, and the preoperative conversation with the patients was also conducted. At the same time, mixed reality technology was used to guide the surgery in real time. Results Mixed reality technology can clearly pre-show the important anatomical structures of blood vessels, trachea, lesions and their positional relationship. With the help of mixed reality technology, the operation went smoothly. The total operation time was 49 min, the precise dorsal resection time was 27 min, and the intraoperative blood loss was about 39 mL. The patient recovered well and was discharged from hospital smoothly after surgery. Conclusion Mixed reality technology has certain application value before and during the surgery for pulmonary nodules. The continuous maturity of this technology and its further application in clinics will not only bring a new direction to the development of thoracic surgery, but also provide a wide prospect.
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The study describes a case of hyper-eosinophilia who was presented with overt manifestation of high eosinophil and detected to have underlying non Hodgkin lymphoma. The male patient was presented with profound weakness and multiple non itchy nodular skin lesion for 2 weeks. Biopsy from skin nodule showed deposits of abnormal lymphocytes. Lymph node biopsy showed effacement with mono nuclear abnormal cells which showed positivity for CD4 and 5, negative for cytokeratin and CD20. He was diagnosed to have T-NHL. [Fig. 3a, Fig. 3b] Bone marrow showed involvement by NHL cells. His diplopia and headache responded to intra-thecal methotrexate and possibly CNS involvement of disease was considered. Family opted out of allopathic treatment plan due to clinical progression. He later died of disease progression. This case illustrates the rare and interesting association of overt clinical hyper-eosinophilia and T NHL. The study suggests that cases with hyper eosinophilia should be evaluated thoroughly for T cell disease.
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@#Peripheral pulmonary lesions (PPLs) are generally considered as lesions in the peripheral one-third of the lung. A computed tompgraphy (CT) guided transthoracic needle aspiration/biopsy or transbronchial approach using a bronchoscope has been the most generally accepted methods. Navigation technique can effectively improve the diagnosis rate of peripheral pulmonary lesions, reduce the incidence of complications, shorten the time of diagnosis, and make the patients get timely and effective treatment.
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Objective: Computed tomography (CT)-guided percutaneous lung biopsy is difficult for small nodules and lesions that are adjacent to large blood vessels. This study investigated the validity of CT-guided percutaneous lung biopsy in the diagnosis of pulmo-nary nodules with a digital angle instrument. Methods: This study was a retrospective analysis of 35 patients with lung mass≤60 mm, who underwent CT-guided percutaneous lung biopsy from January 2018 to September 2018. Patients were assigned in to three groups. Group A and B were patients with pulmonary nodules≤30 mm. Biopsy of group A was performed with the help of a digital an-gle instrument, and group B didn’t use digital angle instrument. Group C had lung mass of>30 mm, and the biopsy was performed without using the instrument. The size of the mass, frequency of punctures, distance of the puncture, and complication of pneumotho-rax after puncture were compared among the three groups. Results: The maximum diameter of pulmonary nodules in group A (18.4 ± 2.1) mm was significantly lower than that in groups B (28.3 ± 2.0) mm and C (43.2 ± 3.6) mm, and their P value were 0.0034 and 0.0028, respectively. Some patients in group A were at risk because of severe chronic obstructive pulmonary disease and proximity of lesions to large blood vessels. The puncture distance in group A was also significantly more than groups B (P<0.039). However, the probability of puncture success in group A was 100%, which was significantly higher than groups B and C. The postoperative complica-tions in group A were also significantly fewer than in other two groups. Conclusions: CT-guided percutaneous lung biopsy with a digital angle instrument is a safe, simple, and accurate diagnostic method, especially in patients with pulmonary nodular lesions.
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BACKGROUND@#The detection of pulmonary nodules is a key step to achieving the early diagnosis and therapy of lung cancer. Deep learning based Artificial intelligence (AI) presents as the state of the art in the area of nodule detection, however, a validation with clinical data is necessary for further application. Therefore, the aim of this study is to evaluate the performance of AI in the detection of malignant and non-calcified nodules in chest CT.@*METHODS@#Two hundred chest computed tomography (CT) data were randomly selected from a self-built nodule database from Tianjin Medical University General Hospital. Both the pathology confirmed lung cancers and the nodules in the process of follow-up were included. All CTs were processed by AI and the results were compared with that of radiologists retrieved from the original medical reports. The ground truths were further determined by two experienced radiologists. The size and characteristics of the nodules were evaluated as well. The sensitivity and false positive rate were used to evaluate the effectiveness of AI and radiologists in detecting nodules. The McNemar test was used to determine whether there was a significant difference.@*RESULTS@#A total of 889 non-calcified nodules were determined by experts on chest CT, including 133 lung cancers. Of them, 442 nodules were less than 5 mm. The cancer detection rates of AI and radiologists are 100%. The sensitivity of AI on nodule detection was significantly higher than that of radiologists (99.1% vs 43%, P<0.001). The false-positive rate of AI was 4.9 per CT and decreased to 1.5 when nodules less than 5 mm were excluded.@*CONCLUSIONS@#AI achieves the detection of all malignancies and improve the sensitivity of pulmonary nodules detection beyond radiologists, with a low false positive rate after excluding small nodules.
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Humanos , Inteligência Artificial , Aprendizado Profundo , Neoplasias Pulmonares , Diagnóstico , Diagnóstico por Imagem , Nódulos Pulmonares Múltiplos , Diagnóstico , Diagnóstico por Imagem , Tomografia Computadorizada por Raios XRESUMO
A method was proposed to detect pulmonary nodules in low-dose computed tomography (CT) images by two-dimensional convolutional neural network under the condition of fine image preprocessing. Firstly, CT image preprocessing was carried out by image clipping, normalization and other algorithms. Then the positive samples were expanded to balance the number of positive and negative samples in convolutional neural network. Finally, the model with the best performance was obtained by training two-dimensional convolutional neural network and constantly optimizing network parameters. The model was evaluated in Lung Nodule Analysis 2016(LUNA16) dataset by means of five-fold cross validation, and each group's average model experiment results were obtained with the final accuracy of 92.3%, sensitivity of 92.1% and specificity of 92.6%.Compared with other existing automatic detection and classification methods for pulmonary nodules, all indexes were improved. Subsequently, the model perturbation experiment was carried out on this basis. The experimental results showed that the model is stable and has certain anti-interference ability, which could effectively identify pulmonary nodules and provide auxiliary diagnostic advice for early screening of lung cancer.
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Humanos , Algoritmos , Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Redes Neurais de Computação , Interpretação de Imagem Radiográfica Assistida por Computador , Tomografia Computadorizada por Raios XRESUMO
Background: Infectious mononucleosis is usually a self-limiting illness, but can be rarelyassociated with complications. Case characteristics: A 17-year-old boy with Epstein-Barrvirus related infectious mononucleosis and cold antibody-mediated autoimmune hemolyticanemia with incidentally noted multiple pulmonary nodules. Observations: Nodulesregressed over the next few weeks without specific therapy. Message: Pediatricians needto be aware of this rare clinical presentation of infectious mononucleosis so that furtherinvasive testing can be avoided.
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Objective To explore the value of virtual monochromatic spectral (VMS) images acquired from dual-energy spectral CT (DESCT) with metal artifact reduction (MAR) algorithm in CT-guided microcoil localization for lung nodules.Methods Totally 80 patients with lung nodules underwent DESCT after CT-guided microcoil placement.At optimal keV level,VMS images and VMS with MAR algorithm (VMS+MAR) images were reconstructed,and image quality scores were compared.Results 74 keV was selected as the optimal level.The image quality of VMS+ MAR images at 74,90,110 and 140 keV were better than that at 50 keV (all P<0.05).There was no statistical difference of image quality among 74,90,110 and 140 keV VMS+MAR images (all P>0.05).At 74 keV,the image quality of VMS+MAR images was better than that of VMS images (P<0.05).The consistency was good between the 2 observers (Kappa=0.78).Conclusion VMS images at 74 keV with MAR algorithm could reduce artifacts from microcoil,and clearly display lung nodules.
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Objective Major challenges in the current automatic detection of lung nodules from chest CT images are to improve the sensitivity and to reduce the false positive rate.A new scheme based on convolutional neural network was proposed in this study.Methods The method applied an automatic anatomy recognition (AAR) methodology based on fuzzy modeling ideas and an iterative relative fuzzy connectedness (IRFC) delineation algorithm for the segmentation of lung parenchyma in CT images.The segmented lung image was inputted into the conventional neural networks for feature extraction of pulmonary nodules.The network adopted position-sensitive score maps to express the location information of lung nodules.Results This method could obtain accurate segmentation of the lung parenchyma in the data set of Tianchi Medical AI Contest,and the accuracy,sensitivity,specificity and false-positive rate of lung nodules detected was 95.60 %,95.24%,95.97% and 4.03%,respectively.Conclusion Detection of pulmonary nodules based on convolutional neural networks has high accuracy and efficiency,and good robustness.
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Objective To analyze the clinical features and common etiology of lung nodules in children. Methods The etiology, diagnosis, radiological features from 98 hospitalized children of lung nodules were analyzed. Results Of them, 58 were male and 40 were female aged from 0.2 years old to 14.8 years old. Pulmonary infection were found in 41 cases (41.8%) including tuberculosis in 15 cases (15.3%), pulmonary fungal infection in 13 cases (13.3%), pneumonia in 11 cases (11.2%), lung trematode in 2 cases (2.0%). Pulmonary metastases were found in 28 cases (28.6%), multiple pulmonary arteriovenous fistula in 1 case (1.0%), and pulmonary contusion in 1 case (1.0%) and unknown etiology in 27 cases (27.6%). Conclusions The etiology of lung nodules is complicated, in which infectious diseases are the most commonly seen, followed by pulmonary metastases. Biopsy is the golden standard of diagnosis.
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Electromagnetic navigational bronchoscopy (ENB), one of the methods of navigational bronchoscopy is an advanced diagnostic tool allowing tissue sampling at the lung peripheries which were previously accessible only by computed tomography (CT) guidance or video-assisted thoracoscopic surgery (VATS). We report a 53-year-old man who presented with a cough and dyspnea with constitutional symptoms for one month. CT thorax revealed multiple bilateral peripheral lung nodules and there were no endobronchial lesions on flexible bronchoscopy. ENB was performed using a loan machine from Veran navigational technology. Biopsy successfully revealed small cell carcinoma of the lung thus preventing him from undergoing a more invasive diagnostic procedure. This case highlights the utility of ENB in the evaluation of peripheral lung nodules that were inaccessible by conventional bronchoscopy. This is one of the first few successful applications of Veran ENB in Asia.
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Alveolar adenoma is a very rare benign intraparenchymal lung tumor originating from type II pneumocytes. It can be mistaken for other benign tumors or lung cancer in radiological images. It is especially difficult to distinguish alveolar adenoma from sclerosing hemangioma. A small aspiration biopsy specimen, such as with percutaneous needle aspiration, is insufficient for a pathological diagnosis. Surgical resection is the only method by which a pathological diagnosis can be made and the disease treated. An alveolar adenoma presenting as multiple nodules is very rare and has to our knowledge not been reported in Korea previously. Here, we report a case of alveolar adenoma in multiple nodules in a 57-year-old female and review the literature.
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Feminino , Humanos , Pessoa de Meia-Idade , Adenoma , Biópsia por Agulha , Diagnóstico , Histiocitoma Fibroso Benigno , Coreia (Geográfico) , Neoplasias Pulmonares , Pulmão , Agulhas , Células Epiteliais AlveolaresRESUMO
OBJECTIVE: To evaluate the effect of computer-aided detection (CAD) system on observer performance in the detection of malignant lung nodules on chest radiograph. MATERIALS AND METHODS: Two hundred chest radiographs (100 normal and 100 abnormal with malignant solitary lung nodules) were evaluated. With CT and histological confirmation serving as a reference, the mean nodule size was 15.4 mm (range, 7-20 mm). Five chest radiologists and five radiology residents independently interpreted both the original radiographs and CAD output images using the sequential testing method. The performances of the observers for the detection of malignant nodules with and without CAD were compared using the jackknife free-response receiver operating characteristic analysis. RESULTS: Fifty-nine nodules were detected by the CAD system with a false positive rate of 1.9 nodules per case. The detection of malignant lung nodules significantly increased from 0.90 to 0.92 for a group of observers, excluding one first-year resident (p = 0.04). When lowering the confidence score was not allowed, the average figure of merit also increased from 0.90 to 0.91 (p = 0.04) for all observers after a CAD review. On average, the sensitivities with and without CAD were 87% and 84%, respectively; the false positive rates per case with and without CAD were 0.19 and 0.17, respectively. The number of additional malignancies detected following true positive CAD marks ranged from zero to seven for the various observers. CONCLUSION: The CAD system may help improve observer performance in detecting malignant lung nodules on chest radiographs and contribute to a decrease in missed lung cancer.
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Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Algoritmos , Diagnóstico por Computador/instrumentação , Diagnóstico Diferencial , Interpretação de Imagem Assistida por Computador , Neoplasias Pulmonares/diagnóstico por imagem , Variações Dependentes do Observador , Curva ROC , Radiografia Torácica , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: The present study was designed to evaluate the effects of urban, traffic-related, fine particulate matter (PM2.5) on mice lung tumorigenesis under controlled exposure conditions. METHODS: Four groups of female Swiss mice were treated with intraperitonial injections of urethane and saline solution. Urethane was used to start the carcinogenesis process. The animals were housed in two chambers receiving filtered and polluted air. In the polluted air chamber, pollutant levels were low. After two months of exposure, the animals were euthanized and lung tumoral nodules were counted. RESULTS: Saline-treated animals showed no nodules. Urethane-treated animals showed 2.0+2.0 and 4.0+3.0 nodules respectively, in the filtered and non-filtered chambers (p = 0.02), thus showing experimental evidence of increased carcinogenic-induced lung cancer with increasing PM2.5 exposure. CONCLUSION: Our data support the concept that low levels of PM2.5 may increase the risk of developing lung tumors.