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1.
PLoS One ; 15(9): e0238760, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32886711

RESUMO

In this study, we ascertained the chest CT data of 60 patients admitted to 3 hospitals in Chongqing with confirmed COVID-19. We conducted anatomical and pathological analyses to elucidate the possible reasons for the distribution, morphology, and characteristics of COVID-19 in chest CT. We also shared a semiquantitative scoring of affected lung segments, which was recommended by our local medical association. This scoring system was applied to quantify the severity of the disease. The most frequent imaging findings of COVID-19 were subpleural ground glass opacities and consolidation; there was a significant difference in semiquantitative scores between the early, progressive, and severe stages of the disease. We conclude that the chest CT findings of COVID-19 showed certain characteristics because of the anatomical features of the human body and pathological changes caused by the virus. Therefore, chest CT is a valuable tool for facilitating the diagnosis of COVID-19 and semiquantitative scoring of affected lung segments may further elucidate diagnosis and assessment of disease severity. This will assist healthcare workers in diagnosing COVID-19 and assessing disease severity, facilitate the selection of appropriate treatment options, which is important for reducing the spread of the virus, saving lives, and controlling the pandemic.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Tomografia Computadorizada Espiral/normas , Adolescente , Adulto , Idoso , Criança , Infecções por Coronavirus/patologia , Feminino , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/patologia , Índice de Gravidade de Doença , Tomografia Computadorizada Espiral/métodos
2.
J Comput Assist Tomogr ; 44(5): 796-805, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32932343

RESUMO

OBJECTIVE: In this article, a statistical-based iterative ring removal (IRR) algorithm that effectively removes ring artifacts generated by defective detector cells is proposed. METHODS: The physical state of computed tomography (CT) detector elements can change dynamically owing to their temperature dependence and the varying irradiation caused by focal spot movements. This variation in the properties of cells may cause false pixel values in sinograms, resulting in rings or segments of rings in reconstructed images. In this article, the proposed algorithm is studied on clinical CT. Two patients were scanned using a clinical CT scanner (AnyScan SPECT/CT, Mediso). Artificial rings and band rings were generated on the real sinogram data to examine the algorithm in different cases. The method was performed also on real ring artifacts. RESULTS: The IRR can correct both single and band-like ring artifacts with one or more defective pixels. The proposed algorithm can detect the period when pixels contain false signals and only those periods are corrected. The IRR reduces ring artifacts, even in cases where low-contrast rings occur in the reconstructed image. CONCLUSIONS: This statistical correction method efficiently detects and corrects false pixel values in the projection data without causing new artifacts in the reconstructed image. The algorithm is less sensitive to its parameters.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada Espiral/métodos , Algoritmos , Humanos
3.
Medicine (Baltimore) ; 99(33): e21719, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32872052

RESUMO

The study was aimed to evaluate the image quality and radiation dose during female chest computed tomography (CT) screening using organ-based tube current modulation technology X-ray combined applications to reduce exposure (XCARE).Five hundred sixty female individuals undergoing chest CT scan were prospectively enrolled and divided into 4 groups based on body mass index (BMI). Then they were randomly and equally divided into control and experimental subgroup and respectively accepted conventional low-dose and XCARE technology spiral CT scan with same parameters. Signal-to-noise ratio and contrast-to-noise ratio were calculated. The quality of the images was evaluated by 2 radiologists using a 5-point scale.Among experimental subgroups of the 4 BMI groups, Signal-to-noise ratios, CT dose index of volume, dose-length product, effective dose, and contrast-to-noise ratio all displayed significant differences, as well as in control subgroups (P < .001). Both the experimental and control subgroups showed an increasing trend in radiation dose with the increasing of BMI. Parameters of image quality and radiation dose displayed no significant differences between control and experimental subgroups in the 4 groups. In multiple linear regression analysis, age and scanning protocol were not associated with radiation dose (P > .05), while BMI was significantly associated with increased CT dose index of volume (P < .05). The display of the lesions for the patients in the control and experimental subgroups of the 4 groups with different BMIs exhibited no statistically significant difference.The same image quality and radiation dose can be obtained using XCARE technology compared to conventional chest CT scans, which can be used regularly in female patients.Advances in knowledge: Using automatic tube current modulation technology to reduce exposure in breast. In this study, we sought a radiation protection method for sensitive tissue in chest CT screening.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Programas de Rastreamento/métodos , Lesões por Radiação/prevenção & controle , Radiografia Torácica/métodos , Tomografia Computadorizada Espiral/métodos , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Melhoria de Qualidade , Doses de Radiação
4.
Rev Assoc Med Bras (1992) ; 66(1): 74-80, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130385

RESUMO

OBJECTIVE: This study aims to investigate the application value of magnetic resonance (MR) hydrography of the inner ear in cochlear implantation. METHODS: 146 patients were enrolled. MR hydrography and spiral CT examinations for the intracranial auditory canal were performed before surgery, and all imaging results were statistically analyzed in order to explore the application value of MR hydrography of the inner ear in cochlear implantation. RESULTS: 146 patients (292 ears) were examined. Among these patients, 13 were diagnosed with abnormal vestibular aqueducts (20 ears) by MR hydrography, while five were diagnosed with this disease by CT; 15 patients were diagnosed with inner ear malformation (19 ears) by MR hydrography, while 11 were diagnosed by CT (four were misdiagnosed); five patients were diagnosed with internal acoustic canal stenosis (eight ears) by MR hydrography, while two were diagnosed by CT (three were misdiagnosed); and four patients were diagnosed with cochlear fibrosis (five ears) by MR hydrography, while four were diagnosed by CT (four ears). The correct rate of diagnosis was 77.40% (113/146) based on CT, while the rate was 93.84% (137/146) based on MR hydrography. CONCLUSIONS: MR hydrography imaging technique can be applied to the preoperative evaluation of cochlear implantation, providing accurate and reliable anatomic information on the inner membranous labyrinth and nerves in the internal acoustic canal and an accurate basis for the diagnosis of cochlear fibrosis and nerve development. This has a guiding significance for the selection of treatment schemes.


Assuntos
Implante Coclear/métodos , Orelha Interna/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Orelha Interna/cirurgia , Feminino , Perda Auditiva Neurossensorial/diagnóstico por imagem , Perda Auditiva Neurossensorial/cirurgia , Humanos , Lactente , Doenças do Labirinto/diagnóstico por imagem , Doenças do Labirinto/cirurgia , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Valores de Referência , Reprodutibilidade dos Testes , Tomografia Computadorizada Espiral/métodos , Adulto Jovem
5.
Sci Rep ; 10(1): 4928, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188899

RESUMO

The helical tomotherapy (HT) Hi-ART system was installed at our department in April 2007. In July 2018 the first Radixact system in Germany has been launched for clinical use. We present differences, advantages and disadvantages and show future perspectives in patient treatment using two HT devices. We investigate patient characteristics, image quality, radiotherapy treatment specifications and analyze the time effort for treatments with the Hi-ART system from April 2010 until May 2017 and compare it to the data acquired in the first nine months of usage of the Radixact system. Comparing the Hi-ART and Radixact system, the unique option of integrated MVCT image acquisition has experienced distinct improvement in image quality. Time effort for irradiation treatment could be improved resulting in a mean beam on time for craniospinal axis treatment of 636.2 s for the Radixact system compared to 915.9 s for the Hi-ART system. The beneficial use of tomotherapy for complex target volumes is demonstrated by a head and neck tumor case and craniospinal axis treatment. With the Radixact system MVCT image quality has been improved allowing for fast and precise interfraction dose adaptation. The improved time effort for patient treatment could increase the accessibility for clinical usage.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Radioterapia Guiada por Imagem , Tomografia Computadorizada Espiral , Gerenciamento Clínico , Alemanha , Humanos , Processamento de Imagem Assistida por Computador , Intensificação de Imagem Radiográfica , Planejamento da Radioterapia Assistida por Computador , Radioterapia Guiada por Imagem/efeitos adversos , Radioterapia Guiada por Imagem/métodos , Radioterapia Guiada por Imagem/normas , Radioterapia de Intensidade Modulada , Tomografia Computadorizada Espiral/métodos , Tomografia Computadorizada Espiral/normas , Resultado do Tratamento , Fluxo de Trabalho
6.
World Neurosurg ; 138: 706-713, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31917307

RESUMO

In this paper, 64-slice spiral computed tomography (CT) retrospective electrocardiographic (ECG) gating technology was used to perform coronary CT angiography scans. The aorta and aortic pulmonary artery diameter were measured quantitatively in healthy people and patients with hypertension and cerebrovascular disease. Corresponding aortic pulmonary artery ratios were obtained through calculation, and the changes of aortic diameter, aortic pulmonary artery ratio, and aortic diameter difference between different cardiac phases, ages, sexes, and levels of hypertension were discussed. Through research, it can be concluded that 64-row spiral CT scan combined with ECG gating technology can accurately measure the dynamic changes of the aortic diameter with the cardiac cycle. At the same time, the aortic diameter measured by multidetector CT scan combined with ECG gating technology and the phase difference between different phases can objectively reflect the degree of arterial damage in patients with hypertension; therefore, early screening of aortic diseases in patients with hypertension can be performed. Diagnosis to detect abnormalities as early as possible and start treatment as early as possible to prevent the disease from progressing and even affecting other tissues and organs can also be obtained.


Assuntos
Aorta/diagnóstico por imagem , Técnicas de Imagem de Sincronização Cardíaca/métodos , Angiografia por Tomografia Computadorizada/métodos , Hipertensão/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta/patologia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/patologia , Estudos de Casos e Controles , Angiografia Coronária/métodos , Diástole , Eletrocardiografia , Feminino , Humanos , Hipertensão/patologia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Tamanho do Órgão , Artéria Pulmonar/patologia , Seio Aórtico/diagnóstico por imagem , Seio Aórtico/patologia , Sístole , Tomografia Computadorizada por Raios X
7.
Eur J Radiol ; 122: 108748, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31775082

RESUMO

PURPOSE: Acute respiratory distress syndrome (ARDS) is an acute inflammatory lung injury that frequently shows fatal outcomes. As radiographic predictive factors, some reports have focused on the region of ill-aerated lung, but none have focused on well-aerated lung. Our objective was to evaluate the relationship between computed tomography (CT) volume of the well-aerated lung region and prognosis in patients with ARDS. METHOD: This retrospective observational study of a single intensive care unit (ICU) included patients with ARDS treated between April 2011 and May 2013. We identified 42 patients with ARDS for whom adequate helical CT scans were available. CT images were analyzed for 3-dimensional reconstruction, and lung region volumes were measured using automated volumetry methods. Lung regions were identified by CT attenuation in Hounsfield units (HU). RESULTS: Of the 42 patients, 35 (83.3 %) survived 28 days and 32 (76.2 %) survived to ICU discharge. CT lung volumetry was performed within 144.5 ±â€¯76.6 s, and inter-rater reliability of CT lung volumetry for lung regions below -500 HU (well-aerated lung region) were near-perfect. Well-aerated lung region showed a positive correlation with 28-day survival (P = 0.020), and lung volumes below -900 HU correlated positively with 28-day survival and ICU survival, respectively (P = 0.028, 0.017). Survival outcome was better for percentage of well-aerated lung region/predicted total lung capacity ≥40 % than for <40 % (P = 0.039). CONCLUSIONS: CT lung volumetry of the well-aerated lung region using an automated method allows fast, reliable quantitative CT analysis and potentially prediction of the clinical course in patients with ARDS.


Assuntos
Síndrome do Desconforto Respiratório do Adulto/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adulto , Feminino , Humanos , Pulmão/diagnóstico por imagem , Medidas de Volume Pulmonar/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Volume de Ventilação Pulmonar/fisiologia , Capacidade Pulmonar Total
8.
J Comput Assist Tomogr ; 44(2): 295-304, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31789681

RESUMO

BACKGROUND: The single line of the normal interlobar fissure shown on a thin section image can be reconstructed as a 5-line sign on axial maximal intensity projection. The line between the lung nodule and the pleura is called the pleural tail sign on thin image. On the axial maximal intensity projection, it can also be reconstructed as the 5-line sign or fewer than 5 lines. OBJECTIVE: This study aimed to observe the effect of 5-line signs in staging, progression, and prognosis of peripheral lung carcinoma. MATERIALS AND METHODS: This study included 132 patients with peripheral lung carcinoma. Among these patients, 93 were men and 39 were women, with an age range of 27 to 82 years and a lung nodule range of 0.98 to 8.75 cm. Maximal intensity projection was reconstructed based on 1.0 or 1.25 mm of thin-slice images in multislice spiral computed tomography. Five-line signs on the margin of the nodule (mass) were observed and were classified into grades 1 to 4 according to the sharpness of the 5-line signs. RESULTS: Multivariate logistic regression analysis showed that the sharpness of the 5-line signs was correlated with N and TNM staging of peripheral lung carcinoma (P = 0.012, P = 0.016). The lower the sharpness of the 5-line signs, the greater the number of cases of progression of the tumor (P < 0.001), and thus the higher the mortality rate and the lower the survival rate (P = 0.001). The sensitivity and specificity of predicting tumor progression were 56.3% and 93.3%, and those of tumor prognosis were 61.1% and 82.4%, respectively. CONCLUSIONS: The sharpness of the 5-line signs has certain effects on the prediction of invasion, progression, and prognosis of lung carcinoma, particularly of small lung cancer (≤3.0 cm).


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Sensibilidade e Especificidade , Taxa de Sobrevida
9.
Clin Imaging ; 59(2): 119-125, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31816538

RESUMO

PURPOSE: To evaluate the accuracy of cyst score measurements by standard high-resolution helical volume chest CT (HRCT) in patients with lymphangioleiomyomatosis (LAM), using a short z-length ultra-high resolution re-scan (UH re-scan) as the reference. In cystic lung diseases, cyst score is derived from CT scans and defined as the percentage of the total lung parenchymal volume occupied by cysts, a biomarker which measures the severity of the disease. METHODS: In a prospective study of 73 LAM patients, each patient received the standard HRCT chest scan and a short z-length UH re-scan. Cyst scores were acquired from both scans using a standard FDA-approved scoring software on the CT scanner. RESULTS: The limited UH re-scan resolved small cysts that were not resolved in the HRCT. The HRCT-derived cyst scores were on average 59.6% of the reference values from the UH re-scan (p = 4.7e-25). The amount of under-estimation by HRCT varied from patient to patient, with an inter-quartile range of 29.8% and standard deviation of 20.7%. The overall trend was more pronounced underestimation for patients with lower cyst scores. For patients whose reference cyst scores were below 15 (n = 29), the HRCT cyst scores were 46.9 ± 21.6% of reference values (p = 7.4e-12), while for the rest of the patients (n = 44) the HRCT cyst scores were 68.0 ± 15.3% of reference values (p = 1.2E-19). Reconstructing the HRCT images to the resolution of the UH re-scan further widened the spread of the discrepancy between HRCT and reference values due to increased image noise, and did not provide accurate cyst scores. CONCLUSION: Cyst scores derived from standard high-resolution helical volume chest CT significantly underestimates the percentage lung volume occupied by cysts. This inaccuracy needs to be taken into consideration when cyst score is used as part of the CT assessment of the patient's condition.


Assuntos
Linfangioleiomiomatose/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Cistos/diagnóstico por imagem , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
10.
Eur Rev Med Pharmacol Sci ; 23(23): 10218-10225, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31841175

RESUMO

OBJECTIVE: This study aimed to investigate the diagnostic value of multi-slice spiral CT (MSCT) in acute mesenteric ischemia. MATERIALS AND METHODS: A systematic review was performed from the databases of PubMed, Web of Science and EMBASE by two researchers updated to July 1, 2018. The search terms included in the databases were mesenteric ischemia and multi-slice spiral computed tomography. A self-made data extraction form was used for data extraction, followed by quality assessment and heterogeneity testing of literature that met the requirements. Combined specificity and sensitivity were calculated and receiver operating characteristic (ROC) analyses were conducted. Meta-analysis was performed by STATA 12.0. RESULTS: In this meta-analysis, 231 patients with acute mesenteric ischemic disease and 651 patients in the control group in 8 independent randomized case-control studies were enrolled. Our meta-analysis showed that MSCT had significantly improved the diagnosis of acute mesenteric ischemia. Because of statistical heterogeneity in the study, we used the random effects model for analysis. The combined sensibility was 94% (95% CI: 83%-98%), and the combined specificity was 97% (95% CI: 93%-99%). The combined positive predictive value was 32.48 (95% CI: 13.53-77.98), the combined negative predictive value was 0.07 (95% CI: 0.02-0.18), and the combined diagnostic odds ratio was 6.21 (95% CI: 4.58-7.84). In terms of comprehensive diagnostic performance, the AUC was 0.99 (95% CI: 0.98-1.00) after plotting the SROC curve. CONCLUSIONS: MSCT had a high sensitivity and specificity for the diagnosis of acute mesenteric ischemia. In addition, these studies with large samples and high quality in a multi-center hospital were needed to further confirm the reliability.


Assuntos
Isquemia Mesentérica/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Doença Aguda , Humanos , Valor Preditivo dos Testes
11.
J Pak Med Assoc ; 69(11): 1711-1713, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31740884

RESUMO

This study was conducted to determine the diagnostic accuracy of CT-guided core needle biopsy (CNB) using coaxial technique of pulmonary lesions, its complications and factors affecting them. A total of 122 patients with suspected lung malignancy underwent CT-guided CNB. Final diagnosis was confirmed by histopathology. There were 84 (89.4%) true positive while 26 (92.9%) true negative cases. Diagnostic accuracy, sensitivity, specificity, PPV, NPV, and overall diagnostic accuracy were 97.67%, 72.22%, 89.36%, 92.86% and 90.16% respectively. Pneumothorax was the only complication observed in 10 (8.2%) patients. The odds of pneumothorax was found to be 10.72 times higher among patients with 2.5cm of size of lesions (AOR 10.72, 95% CI 1.49-76.77) while 86% lower among patients having prone position (AOR 0.14, 95% CI 0.021-0.96). Results indicate that percutaneous CT guided biopsy of pulmonary lesions using coaxial technique is a safe procedure with a high diagnostic accuracy and lesser risk of major complications.


Assuntos
Biópsia com Agulha de Grande Calibre , Biópsia Guiada por Imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Tomografia Computadorizada Espiral , Idoso , Biópsia com Agulha de Grande Calibre/efeitos adversos , Biópsia com Agulha de Grande Calibre/métodos , Biópsia com Agulha de Grande Calibre/estatística & dados numéricos , Feminino , Humanos , Biópsia Guiada por Imagem/efeitos adversos , Biópsia Guiada por Imagem/métodos , Biópsia Guiada por Imagem/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pneumotórax , Complicações Pós-Operatórias , Estudos Retrospectivos , Tomografia Computadorizada Espiral/efeitos adversos , Tomografia Computadorizada Espiral/métodos , Tomografia Computadorizada Espiral/estatística & dados numéricos
12.
Med Sci Monit ; 25: 8492-8498, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31710020

RESUMO

BACKGROUND More and more patients with lung adenocarcinoma were detected with ground glass nodule (GGN) due to the popularity of low-dose spiral computed tomography (LDCT) recently. The clinicopathological characteristics and epidermal growth factor receptor (EGFR) mutation features were unclear. MATERIAL AND METHODS This retrospective study enrolled patients with surgical resected primary lung adenocarcinomas with GGN component. The clinicopathological data included age, gender, smoking history, tumor staging, lymph node staging, surgical methods, subtypes, thyroid transcription factor-1 (TTF-1) expression, EGFR gene mutation and follow-up records were investigated. RESULTS There were 338 lung adenocarcinoma patients with GGN component eligible for our analysis: 219 patients (64.8%) harbored the EGFR mutation. In addition, the EGFR mutation rate was higher in patients with TTF-1+ than in patients with TTF-1- (72 out of 108 patients, 66.7% versus 147 out of 231 patients, 63.6%). In multivariable analysis, surgical procedure, tumor size, nodal stage, and subtype were still significant factors for relapse-free survival (RFS) while only subtype acted as the significant factor for overall survival (OS). In subgroup analyses, patients with TTF-1- had better prognosis in RFS (log-rank P=0.0142) when compared with those with TTF-1+ but not in OS (log-rank P=0.1113). Furthermore, patients with high-risk subtype had worse outcomes than those with low-risk subtype (RFS: log-rank P<0.0001; OS: log-rank P<0.0001). Patients who underwent limited resection experienced high risk of relapse (log-rank P<0.0001) while there was no statistical significance in OS (log-rank P=0.1644) between patients underwent lobectomy and those underwent limited resection. CONCLUSIONS The prognosis of lung adenocarcinomas with GGN component depends mainly on the pathological subtype and there is no significant correlation between EGFR mutation and prognosis. Lobectomy should be performed actively in patients whose preoperative puncture biopsy or intraoperative freezing indicates an invasive or worse subtype. For postoperative patients, we should consider follow-up more frequently.


Assuntos
Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/patologia , Tomografia Computadorizada Espiral/métodos , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Proteínas de Ligação a DNA/genética , Intervalo Livre de Doença , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Pneumonectomia/mortalidade , Prognóstico , Estudos Retrospectivos , Fatores de Transcrição/genética
13.
Eur J Radiol ; 119: 108657, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31521876

RESUMO

PURPOSE: This study investigated the impact of gender differences on the diagnostic performance of machine-learning based coronary CT angiography (cCTA)-derived fractional flow reserve (CT-FFRML) for the detection of lesion-specific ischemia. METHOD: Five centers enrolled 351 patients (73.5% male) with 525 vessels in the MACHINE (Machine leArning Based CT angiograpHy derIved FFR: a Multi-ceNtEr) registry. CT-FFRML and invasive FFR ≤ 0.80 were considered hemodynamically significant, whereas cCTA luminal stenosis ≥50% was considered obstructive. The diagnostic performance to assess lesion-specific ischemia in both men and women was assessed on a per-vessel basis. RESULTS: In total, 398 vessels in men and 127 vessels in women were included. Compared to invasive FFR, CT-FFRML reached a sensitivity, specificity, positive predictive value, and negative predictive value of 78% (95%CI 72-84), 79% (95%CI 73-84), 75% (95%CI 69-79), and 82% (95%CI: 76-86) in men vs. 75% (95%CI 58-88), 81 (95%CI 72-89), 61% (95%CI 50-72) and 89% (95%CI 82-94) in women, respectively. CT-FFRML showed no statistically significant difference in the area under the receiver-operating characteristic curve (AUC) in men vs. women (AUC: 0.83 [95%CI 0.79-0.87] vs. 0.83 [95%CI 0.75-0.89], p = 0.89). CT-FFRML was not superior to cCTA alone [AUC: 0.83 (95%CI: 0.75-0.89) vs. 0.74 (95%CI: 0.65-0.81), p = 0.12] in women, but showed a statistically significant improvement in men [0.83 (95%CI: 0.79-0.87) vs. 0.76 (95%CI: 0.71-0.80), p = 0.007]. CONCLUSIONS: Machine-learning based CT-FFR performs equally in men and women with superior diagnostic performance over cCTA alone for the detection of lesion-specific ischemia.


Assuntos
Angiografia por Tomografia Computadorizada/normas , Estenose Coronária/diagnóstico por imagem , Isquemia Miocárdica/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Angiografia Coronária/normas , Estenose Coronária/fisiopatologia , Métodos Epidemiológicos , Feminino , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Hemodinâmica/fisiologia , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Fatores Sexuais , Tomografia Computadorizada Espiral/métodos , Tomografia Computadorizada Espiral/normas
14.
Phys Med Biol ; 64(21): 215006, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31461411

RESUMO

Dynamic collimation is an important dose reduction mechanism for helical CT scans, especially for modern wide-beam scanner models. Its implementation and efficacy need to be studied to optimize CT scan protocols and to reduce unnecessary patient dose. The purpose of this study is to evaluate dynamic beam collimation for modern wide-beam CT scanners with direct measurements and to estimate the efficacy for dose reduction. By using a linear-array solid state detector, primary x-ray beam coverage was measured for four CT scanner models: GE Revolution CT, Siemens Somatom Force, Philips iQon, and GE LightSpeed VCT. Supported independently from patient table, the detector remained stationary at the isocenter during helical scans. Data lines were recorded every 0.24 ms throughout one entire helical scan, with a spatial resolution of 0.8 mm along the craniocaudal direction. The measurements were repeated for various scan parameters related to dynamic collimation, including beam collimation width, pitch, rotation time, and scan length. The recorded beam coverage area was used as a surrogate to total primary dose, to model different dynamic collimation mechanisms. The directly measured total radiation range was compared to table travel distance and nominal scan length which equals to the ratio between DLP and CTDIvol. Equations to calculate the percentage dose reduction with dynamic collimation were derived for different mechanisms. Three different dynamic collimation mechanisms were revealed and related linear model parameters were reported for different helical scan parameters. The nominal scan length used to calculate DLP was shown to vary for different dynamic collimation mechanisms. For typical head and abdomen scans with nominal scan lengths of 17.5 cm and 25 cm, percentage dose reduction from dynamic collimation ranged from 2% to 32%. In conclusion, with direct measurements of primary x-ray beam coverage, dynamic collimation mechanisms and related dose reduction effects were characterized for four modern wide-beam CT scanners.


Assuntos
Tomógrafos Computadorizados/normas , Tomografia Computadorizada Espiral/métodos , Humanos , Doses de Radiação , Tomografia Computadorizada Espiral/instrumentação
15.
Eur J Radiol ; 118: 231-238, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31439247

RESUMO

PURPOSE: Cervical lymph node (LN) metastasis of papillary thyroid carcinoma (PTC) is critical for treatment and prognosis. We explored the feasibility of using radiomics to preoperatively predict cervical LN metastasis in PTC patients. METHOD: Total 221 PTC patients (training cohort: n = 154; validation cohort: n = 67; divided randomly at the ratio of 7:3) were enrolled and divided into 2 groups based on LN pathologic diagnosis (N0: n = 118; N1a and N1b: n = 88 and 15, respectively). We extracted 546 radiomic features from non-contrast and venous contrast-enhanced computed tomography (CT) images. We selected 8 groups of candidate feature sets by minimum redundancy maximum relevance (mRMR), and obtained 8 radiomic sub-signatures by support vector machine (SVM) to construct the radiomic signature. Incorporating the radiomic signature, CT-reported cervical LN status and clinical risk factors, a nomogram was constructed using multivariable logistic regression. The nomogram's calibration, discrimination, and clinical utility were assessed. RESULTS: The radiomic signature was associated significantly with cervical LN status (p < 0.01 for both training and validation cohorts). The radiomic signature showed better predictive performance than any radiomic sub-signatures devised by SVM. Addition of radiomic signature to the nomogram improved the predictive value (area under the curve (AUC), 0.807 to 0.867) in the training cohort; this was confirmed in an independent validation cohort (AUC, 0.795 to 0.822). Good agreement was observed using calibration curves in both cohorts. Decision curve analysis demonstrated the radiomic nomogram was worthy of clinical application. CONCLUSIONS: Our radiomic nomogram improved the preoperative prediction of cervical LN metastasis in PTC patients.


Assuntos
Linfonodos/patologia , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Meios de Contraste , Detecção Precoce de Câncer/métodos , Estudos de Viabilidade , Feminino , Humanos , Metástase Linfática , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Pescoço , Nomogramas , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Cuidados Pré-Operatórios/métodos , Prognóstico , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada Espiral/métodos , Adulto Jovem
16.
Clin Respir J ; 13(8): 513-520, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31287237

RESUMO

PURPOSE: to evaluate the current rate of pulmonary embolism (PE) in our medico-surgical intensive care unit (ICU), to identify risk factors, and to determine the outcome of PE in ICU. METHODS: We performed a prospective cohort study of consecutive patients requiring intensive care admission during a one-year period. We included, in this prospective study, all the patients with confirmed PE admitted in ICU with more than 18 years of age, and expected to stay in ICU for more than 48 hours. Only the patients who had a clinical suspicion (unexplained hypoxemia and/or shock) for PE underwent diagnostic studies. RESULTS: During the study period, 842 patients were admitted in our ICU. One hundred and two patients were excluded. The diagnosis of PE was confirmed in 75 patients (10.1%). In our study, all patients (100%) had received some forms of pharmaceutical prophylaxis (PP) during ICU stay. The median time from ICU admission to diagnosis of PE was 6 days. The diagnosis of PE was made by spiral CT in 74 patients (98.7%), and by echocardiography in 1 case (1.3%). The mean ICU stay was 26.3 ± 26.5 days (median: 20 days). During their ICU stay, 73 patients (97.3%) developed one, or more, organ failure. Respiratory failure was the most observed (97.3%). Moreover, 38 patients (50.6%) developed nosocomial infections and 29 (38.6%) died. The multivariate analysis showed that the risk factors associated with mortality were the presence of shock the day of PE diagnosis and the presence of right ventricular dilatation on echocardiography. CONCLUSION: Our findings confirm that subjects in the ICU are at high risk of PE, due to a high number of risk-factors. PE was associated with higher ICU mortality and a significantly higher ICU LOS. Our results invite to revise the preventive strategies of deep venous thrombosis and PE in patients requiring ICU admission.


Assuntos
Infecção Hospitalar/etiologia , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/mortalidade , Adulto , Idoso , Infecção Hospitalar/mortalidade , Ecocardiografia/métodos , Feminino , Humanos , Hipertrofia Ventricular Direita/diagnóstico por imagem , Unidades de Terapia Intensiva/estatística & dados numéricos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Embolia Pulmonar/epidemiologia , Embolia Pulmonar/prevenção & controle , Insuficiência Respiratória/etiologia , Fatores de Risco , Tomografia Computadorizada Espiral/métodos , Trombose Venosa/complicações , Trombose Venosa/prevenção & controle
17.
Medicine (Baltimore) ; 98(28): e16374, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31305437

RESUMO

This study aims to evaluate the diagnostic accuracy and clinical application value of multi-slice spiral CT (MSCT) enhanced scans combined with multiplanar reformations (MPRs) images compared with postoperative pathological results in preoperative T staging of rectal cancer.One hundred sixty-eight consecutive patients with rectal cancer were admitted in our hospital between January 2013 and October 2018. Conventional MSCT plain scans, multi-phase dynamic contrast-enhanced scans, and MPRs were performed in all patients before surgical operation. The preoperative T staging of the rectal cancer lesions was evaluated using MSCT enhanced scans combined with MPRs, which was verified by postoperative pathological results. The diagnostic accuracy of MSCT enhanced scans combined with MPRs in evaluating T staging of the rectal cancer lesions were analyzed by χ test and Kappa test.Compared with postoperative pathology, T staging using MSCT enhanced scans combined with MPRs had overall accuracy of 85.7%. Consistency between MSCT enhanced scans combined with MPRs and postoperative pathological staging was effective for T staging (Kappa = 0.658, χ = 4.200, P = .122).Conventional MSCT enhanced scans combined with MPRs are simple and feasible. It is consistent with the pathological diagnosis of evaluating T staging in the rectal cancer lesions. It can provide reliable imaging evidence for the preoperative evaluation of primary rectal cancer, especially in patients with magnetic resonance imaging (MRI) contraindications, or in grass-roots hospitals due to lack of MRI equipment.


Assuntos
Neoplasias Retais/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Pré-Operatórios , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Estudos Retrospectivos
19.
J Appl Clin Med Phys ; 20(7): 160-165, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31165567

RESUMO

PURPOSE: We propose a novel method to assess overbeaming and overranging, as well as the effect of reducing longitudinal exposure range, by using a dynamic z-collimator in area detector computed tomography. METHODS AND MATERIALS: A 500-mm diameter cylindrical imaging plate was exposed by helical scanning in a dark room. The beam collimation of the helical acquisitions was set at 32 and 80 mm. Overbeaming and overranging with the dynamic z-collimator were measured. RESULTS: The actual beam widths were approximately 39 and 88 mm at 32 and 80 mm collimation, respectively, and were relatively reduced owing to increased beam collimation. Overranging was 27.0 and 48.2 mm with a pitch of 0.83 and 1.49 at 32 mm collimation and 72.5 and 83.1 mm with a pitch of 0.87 and 0.99 at 80 mm collimation. The dynamic z-collimator relatively reduced the overranging by 17.3% and 17.1% for the 32 and 80 mm collimation, respectively. CONCLUSION: We devised a method to simultaneously measure overbeaming and overranging with only one helical acquisition. Although the dynamic z-collimator reduced the overranging by approximately 17%, wider collimation widths and higher pitch settings would increase the exposure dose outside the scan range.


Assuntos
Imagens de Fantasmas , Tomografia Computadorizada Espiral/métodos , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Doses de Radiação , Proteção Radiológica , Tomografia Computadorizada Espiral/instrumentação
20.
Eur Radiol ; 29(12): 6858-6866, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31175414

RESUMO

OBJECTIVES: Diagnostic performance and potential radiation dose reduction of wide-area detector CT sequential acquisition ("wide-volume" acquisition (WV)) in unenhanced chest examination are unknown. This study aims to assess the image quality, the diagnostic performance, and the radiation dose reduction of WV mode compared with the classical helical acquisition for lung parenchyma analysis in an ultra-low-dose (ULD) protocol. METHODS: After Institutional Review Board Approval and written informed consent, 64 patients (72% men; 67.6 ± 9.7 years old; BMI 26.1 ± 5.3 kg/m2) referred for a clinically indicated unenhanced chest CT were prospectively included. All patients underwent, in addition to a standard helical acquisition (120 kV, automatic tube current modulation), two ULD acquisitions (135 kV, fixed tube current at 10 mA): one in helical mode and one in WV mode. Image noise, subjective image quality (5-level Likert scale), and diagnostic performance for the detection of 9 predetermined parenchymal abnormalities were assessed by two radiologists and compared using the chi-square or Fisher non-parametric tests. RESULTS: Subjective image quality (4.2 ± 0.7 versus 4.2 ± 0.8, p = 0.56), image noise (41.7 ± 8 versus 40.9 ± 8.7, p = 0.3), and diagnostic performance were equivalent between ULD WV and ULD helical. Radiation dose was significantly lower for the ULD WV acquisition (mean dose-length product 14.1 ± 1.3 mGy cm versus 15.8 ± 1.3, p < 0.0001). CONCLUSION: An additional 11% dose reduction is achieved with the WV mode in ULD chest CT with fixed tube current, with equivalent image quality and diagnostic performance when compared with the helical acquisition. KEY POINTS: • Image quality and diagnostic performance of ultra-low-dose unenhanced chest CT are identical between wide-volume mode and the reference helical acquisition. • Wide-volume mode allows an additional radiation dose reduction of 11% (mean dose-length product 14.1 ± 1.3 mGy cm versus 15.8 ± 1.3, p < 0.0001).


Assuntos
Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos Clínicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Tomografia Computadorizada Espiral/métodos
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