Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 418.945
Filtrar
1.
J Pediatr Endocrinol Metab ; 35(3): 333-339, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-34952557

RESUMO

OBJECTIVES: This study aimed to determine the prevalence rate of gynecomastia, determine mean glandular breast tissue sizes, and evaluate whether there is any difference in the prevalence rate of gynecomastia according to age using three different reference values of glandular breast tissue size (≥5, ≥10, ≥20 mm) in the pediatric age group. METHODS: Glandular breast tissue sizes were measured retrospectively from thoracic computed tomography (CT) images taken for other reasons in 961 boys aged 1-18 years. RESULTS: When each breast was evaluated separately (1,922 breasts), gynecomastia was observed in 1,001 (52.1%), 719 (37.4%), and 216 (11.2%) breasts with ≥5, ≥10, and ≥20 mm considered as reference values, respectively. A significant difference was found in terms of gynecomastia (p<0.001) and mean glandular breast tissue size (p<0.001) with respect to age. CONCLUSIONS: New studies are currently needed to determine the glandular breast tissue size and the prevalence rate of gynecomastia in boys, and thoracic CT images can be used for this purpose.


Assuntos
Ginecomastia , Adolescente , Criança , Pré-Escolar , Ginecomastia/diagnóstico por imagem , Ginecomastia/epidemiologia , Humanos , Achados Incidentais , Lactente , Masculino , Prevalência , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
2.
Mol Imaging Biol ; 24(1): 60-69, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34622425

RESUMO

PURPOSE: To evaluate the correlation of radiomic features in pelvic [2-deoxy-2-18F]fluoro-D-glucose positron emission tomography/magnetic resonance imaging and computed tomography ([18F]FDG PET/MRI and [18F]FDG PET/CT) in patients with primary cervical cancer (CCa). PROCEDURES: Nineteen patients with histologically confirmed primary squamous cell carcinoma of the cervix underwent same-day [18F]FDG PET/MRI and PET/CT. Two nuclear medicine physicians performed a consensus reading in random order. Free-hand regions of interest covering the primary cervical tumors were drawn on PET, contrast-enhanced pelvic CT, and pelvic MR (T2 weighted and ADC) images. Several basic imaging features, standard uptake values (SUVmean, SUVmax, and SUVpeak), total lesion glycolysis (TLG), metabolic tumor volume (MTV), and more advanced texture analysis features were calculated. Pearson's correlation test was used to assess the correlation between each pair of features. Features were compared between local and metastatic tumors, and their role in predicting metastasis was evaluated by receiver operating characteristic curves. RESULTS: For a total of 101 extracted features, 1104/5050 pairs of features showed a significant correlation (ρ ≥ 0.70, p < 0.05). There was a strong correlation between 190/484 PET pairs of features from PET/MRI and PET/CT, 91/418 pairs of CT and PET from PET/CT, 79/418 pairs of T2 and PET from PET/MRI, and 50/418 pairs of ADC and PET from PET/MRI. Significant difference was seen between eight features in local and metastatic tumors including MTV, TLG, and entropy on PET from PET/CT; MTV and TLG on PET from PET/MRI; compactness and entropy on T2; and entropy on ADC images. CONCLUSIONS: We demonstrated strong correlation of many extracted radiomic features between PET/MRI and PET/CT. Eight radiomic features calculated on PET/CT and PET/MRI were significantly different between local and metastatic CCa. This study paves the way for future studies to evaluate the diagnostic and predictive potential of radiomics that could guide clinicians toward personalized patients care.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias do Colo do Útero , Feminino , Fluordesoxiglucose F18 , Humanos , Imageamento por Ressonância Magnética , Projetos Piloto , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Carga Tumoral , Neoplasias do Colo do Útero/diagnóstico por imagem
3.
Transpl Int ; 35: 10289, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35664428

RESUMO

Organ transplantation is performed worldwide, but policies regarding donor imaging are not uniform. An overview of the policies in different regions is missing. This study aims to investigate the various protocols worldwide on imaging in deceased organ donation. An online survey was created to determine the current policies. Competent authorities were approached to fill out the survey based on their current protocols. In total 32 of the 48 countries approached filled out the questionnaire (response rate 67%). In 16% of the countries no abdominal imaging is required prior to procurement. In 50%, abdominal ultrasound (US) is performed to screen the abdomen and in 19% an enhanced abdominal Computed Tomography (CT). In 15% of the countries both an unenhanced abdominal CT scan and abdominal US are performed. In 38% of the countries a chest radiographic (CXR) is performed to screen the thorax, in 28% only a chest CT, and in 34% both are performed. Policies regarding radiologic screening in deceased organ donors show a great variation between different countries. Consensus on which imaging method should be applied is missing. A uniform approach will contribute to quality and safety, justifying (inter)national exchange of organs.


Assuntos
Abdome , Obtenção de Tecidos e Órgãos , Abdome/diagnóstico por imagem , Consenso , Guias como Assunto , Humanos , Doadores de Tecidos , Tomografia Computadorizada por Raios X
5.
Comput Biol Med ; 146: 105691, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35691714

RESUMO

Lung cancer is among the deadliest cancers. Besides lung nodule classification and diagnosis, developing non-invasive systems to classify lung cancer histological types/subtypes may help clinicians to make targeted treatment decisions timely, having a positive impact on patients' comfort and survival rate. As convolutional neural networks have proven to be responsible for the significant improvement of the accuracy in lung cancer diagnosis, with this survey we intend to: show the contribution of convolutional neural networks not only in identifying malignant lung nodules but also in classifying lung cancer histological types/subtypes directly from computed tomography data; point out the strengths and weaknesses of slice-based and scan-based approaches employing convolutional neural networks; and highlight the challenges and prospective solutions to successfully apply convolutional neural networks for such classification tasks. To this aim, we conducted a comprehensive analysis of relevant Scopus-indexed studies involved in lung nodule diagnosis and cancer histology classification up to January 2022, dividing the investigation in convolutional neural network-based approaches fed with planar or volumetric computed tomography data. Despite the application of convolutional neural networks in lung nodule diagnosis and cancer histology classification is a valid strategy, some challenges raised, mainly including the lack of publicly-accessible annotated data, together with the lack of reproducibility and clinical interpretability. We believe that this survey will be helpful for future studies involved in lung nodule diagnosis and cancer histology classification prior to lung biopsy by means of convolutional neural networks.


Assuntos
Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico , Redes Neurais de Computação , Estudos Prospectivos , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos
7.
Tomography ; 8(3): 1184-1195, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35645383

RESUMO

Prior studies variably reported residual chest CT abnormalities after COVID-19. This study evaluates the CT patterns of residual abnormalities in severe COVID-19 pneumonia survivors. All consecutive COVID-19 survivors who received a CT scan 5-7 months after severe pneumonia in two Italian hospitals (Reggio Emilia and Parma) were enrolled. Individual CT findings were retrospectively collected and follow-up CT scans were categorized as: resolution, residual non-fibrotic abnormalities, or residual fibrotic abnormalities according to CT patterns classified following standard definitions and international guidelines. In 225/405 (55.6%) patients, follow-up CT scans were normal or barely normal, whereas in 152/405 (37.5%) and 18/405 (4.4%) patients, non-fibrotic and fibrotic abnormalities were respectively found, and 10/405 (2.5%) had post-ventilatory changes (cicatricial emphysema and bronchiectasis in the anterior regions of upper lobes). Among non-fibrotic changes, either barely visible (n = 110/152) or overt (n = 20/152) ground-glass opacities (GGO), resembling non-fibrotic nonspecific interstitial pneumonia (NSIP) with or without organizing pneumonia features, represented the most common findings. The most frequent fibrotic abnormalities were subpleural reticulation (15/18), traction bronchiectasis (16/18) and GGO (14/18), resembling a fibrotic NSIP pattern. When multiple timepoints were available until 12 months (n = 65), residual abnormalities extension decreased over time. NSIP, more frequently without fibrotic features, represents the most common CT appearance of post-severe COVID-19 pneumonia.


Assuntos
Bronquiectasia , COVID-19 , Pneumonias Intersticiais Idiopáticas , Doenças Pulmonares Intersticiais , Anormalidades do Sistema Respiratório , COVID-19/diagnóstico por imagem , Progressão da Doença , Seguimentos , Humanos , Pulmão/diagnóstico por imagem , Estudos Retrospectivos , Sobreviventes , Tomografia Computadorizada por Raios X
8.
Tomography ; 8(3): 1196-1207, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35645384

RESUMO

BACKGROUND: The aim of this study was to identify the most accurate computed-tomography (CT) dimensional criteria of loco-regional lymph nodes (LNs) for detecting nodal metastases in gastric cancer (GC) patients. METHODS: Staging CTs of surgically resected GC were jointly reviewed by two radiologists, considering only loco-regional LNs with a long axis (LA) ≥ 5 mm. For each nodal group, the short axis (SA), volume and SA/LA ratio of the largest LN, the sum of the SAs of all LNs, and the mean of the SA/LA ratios were plotted in ROC curves, taking the presence/absence of metastases at histopathology for reference. On a per-patient basis, the sums of the SAs of all LNs, and the sums of the SAs, volumes, and SA/LA ratios of the largest LNs in all nodal groups were also plotted, taking the presence/absence of metastatic LNs in each patient for reference. RESULTS: Four hundred and forty-three nodal groups were harvested during surgery from 107 patients with GC, and 173 (39.1%) were metastatic at histopathology. By nodal group, the sum of the SAs showed the best Area Under the Curve (AUC), with a sensitivity/specificity of 62.4/72.6% using Youden's index with a >8 mm cutoff. In the per-patient analysis, the sum of the SAs of all LNs in the loco-regional nodal groups showed the best AUC with a sensitivity/specificity of 65.6%/83.7%, using Youden's index with a >39 mm cutoff. CONCLUSION: In patients with GC, the sum of the SAs of all the LNs at staging CT is the best predictor among dimensional LNs criteria of both metastatic invasion of the nodal group and the presence of metastatic LNs.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Metástase Linfática/diagnóstico por imagem , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Tomografia Computadorizada por Raios X
9.
Tomography ; 8(3): 1244-1259, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35645389

RESUMO

This study aimed to generate synthetic MR images from real CT images. CT# mean and standard deviation of a moving window across every pixel in the reconstructed CT images were mapped to their corresponding tissue-mimicking types. Identification of the tissue enabled remapping it to its corresponding intrinsic parameters: T1, T2, and proton density (ρ). Lastly, synthetic weighted MR images of a selected slice were generated by simulating a spin-echo sequence using the intrinsic parameters and proper contrast parameters (TE and TR). Experiments were performed on a 3D multimodality abdominal phantom and on human knees at different TE and TR parameters to confirm the clinical effectiveness of the approach. Results demonstrated the validity of the approach of generating synthetic MR images at different weightings using only CT images and the three predefined mapping functions. The slope of the fitting line and percentage root-mean-square difference (PRD) between real and synthetic image vector representations were (0.73, 10%), (0.9, 18%), and (0.2, 8.7%) for T1-, T2-, and ρ-weighted images of the phantom, respectively. The slope and PRD for human knee images, on average, were 0.89% and 18.8%, respectively. The generated MR images provide valuable guidance for physicians with regard to deciding whether acquiring real MR images is crucial.


Assuntos
Articulação do Joelho , Imageamento por Ressonância Magnética , Humanos , Articulação do Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Prótons , Tomografia Computadorizada por Raios X
10.
Tomography ; 8(3): 1260-1269, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35645390

RESUMO

BACKGROUND: To compare a model-based iterative reconstruction (MBIR) versus a hybrid iterative reconstruction (HIR) for initial and final Alberta Stroke Program Early Ct Score (ASPECT) scoring in acute ischemic stroke (AIS). We hypothesized that MBIR designed for brain computed tomography (CT) could perform better than HIR for ASPECT scoring. METHODS: Among patients who had undergone CT perfusion for AIS between April 2018 and October 2019 with a follow-up imaging within 7 days, we designed a cohort of representative ASPECTS. Two readers assessed regional-cerebral-blood-volume-ASPECT (rCBV-ASPECTS) on the initial exam and final-ASPECTS on the follow-up non-contrast-CT (NCCT) in consensus. Four readers performed independently MBIR and HIR ASPECT scoring on baseline NCCT. RESULTS: In total, 294 hemispheres from 147 participants (average age of 69.59 ± 15.63 SD) were analyzed. Overall raters' agreement between rCBV-map and MBIR and HIR ranged from moderate to moderate (κ = 0.54 to κ = 0.57) with HIR and moderate to substantial (κ = 0.52 to κ = 0.74) with MBIR. Overall raters' agreement between follow-up imaging and HIR/MBIR ranged from moderate to moderate (κ = 0.55 to κ = 0.59) with HIR and moderate to almost perfect (κ = 0.48 to κ = 0.82) with MBIR. CONCLUSIONS: ASPECT scoring with MBIR more closely matched with initial and final infarct extent than classical HIR NCCT reconstruction.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Humanos , AVC Isquêmico/diagnóstico por imagem , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
11.
Tomography ; 8(3): 1386-1400, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35645398

RESUMO

Current strategies for the evaluation of patients with chest pain have significantly changed thanks to the implemented potentiality of CT and MRI. The possible fatal consequences and high malpractice costs of missed acute coronary syndromes lead to unnecessary hospital admissions every year. CT provides consistent diagnostic support, mainly in suspected coronary disease in patients with a low or intermediate pre-test risk. Moreover, it can gain information in the case of cardiac involvement in pulmonary vascular obstructive disease. MRI, on the other hand, has a leading role in the condition of myocardial damage irrespective of the underlying inflammatory or stress related etiology. This article discusses how radiology techniques (CT and MRI) can impact the diagnostic workflow of the most common cardiac and vascular pathologies that are responsible for non-traumatic chest pain admissions to the Emergency Department.


Assuntos
Síndrome Coronariana Aguda , Emergências , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/diagnóstico por imagem , Dor no Peito/diagnóstico por imagem , Dor no Peito/etiologia , Humanos , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X
12.
Tomography ; 8(3): 1401-1412, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35645399

RESUMO

BACKGROUND: The purpose of the present study is to evaluate the patient comfort during CT examinations with a modern CT scanner (Photon-Counting CT (PCCT)) and to compare the perceived patient comfort with a standard CT scanner. METHODS: A total of 157 patients participated in this study and completed a questionnaire on their subjective perceptions after their CT examination. The following aspects of comfort were rated on a 5-point Likert scale: (1) claustrophobia in general and during the examination, (2) the effort to lie down and to get up from the CT table, (3) the speed and comfort of the CT table, (4) the difficulty of holding the breath during the CT scan, and (5) the communication during the examination. RESULTS: Patients rated the modern CT scanner significantly better in terms of speed and comfort of the CT table and in terms of difficulty of holding their breath during the CT scan. The answers regarding the other aspects of comfort did not reveal significant differences. When asked for a comparison, patients who did perceive a difference between both scanners rated the modern CT scanner as more comfortable in all aspects of comfort. CONCLUSIONS: The survey did not reveal any major deficits in terms of comfort on the standard CT scanner. However, patients perceived the structural changes positively and appreciated the comfort of a modern CT scanner.


Assuntos
Conforto do Paciente , Tomografia Computadorizada por Raios X , Humanos , Tomógrafos Computadorizados
13.
J Cardiothorac Surg ; 17(1): 134, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35641960

RESUMO

BACKGROUND: Solitary fibrous tumor of the pleura (SFTP) is a rare mesenchymal tumor that arises at various sites and typically originates from the pleura. Most patients with SFTPs are asymptomatic, unless the tumor is large. Approximately 20% of SFTP cases are malignant. There are few reports on imaging diagnoses and interventional treatments of SFTP. Here, we report a case of a giant SFTP that exhibited malignant behavior and underwent successful resection after embolization of the main supply artery of the tumor. CASE PRESENTATION: We report a clinical case of a giant SFTP in a 66-year-old Chinese female patient complaining of chest tightness and cough for more than 2 months. Ten years ago, the patient had undergone a chest CT scan at a local hospital for cough. Computed tomography (CT) had revealed a mass in the right thoracic region, which was misdiagnosed as a pulmonary abscess by CT-guided biopsy. Therefore, the patient did not receive appropriate/complete treatment at that time. She was hospitalized again, because CT showed significant enlargement of the right thoracic mass, which caused her obvious symptoms of discomfort. The pathological results of CT-guided biopsy at our hospital confirmed SFTP. Considering the large size of the tumor and the rich blood supply, some of the main blood vessels were treated with embolization before surgical resection. A large tumor, about 23 cm × 16 cm × 15 cm in size, was then successfully removed by thoracic surgery. The diagnosis of malignant SFTP was confirmed by surgical pathology and immunohistochemistry. CONCLUSION: Imaging findings of SFTPs are not characteristic, especially when a tumor is large, the diagnosis is difficult, and the final diagnosis still depends on histological and immunohistochemical examinations. The two-stage surgical treatment described here, which involves first embolization of the main supplying artery of the large tumor and then complete surgical resection, is effective and safe for SFTPs. Whether needle biopsy or vascular embolization is performed, intervention plays a crucial role in the diagnosis and treatment of patients with SFTPs.


Assuntos
Embolização Terapêutica , Fibrossarcoma , Tumor Fibroso Solitário Pleural , Idoso , Tosse , Feminino , Humanos , Pleura/patologia , Pleura/cirurgia , Tumor Fibroso Solitário Pleural/diagnóstico , Tumor Fibroso Solitário Pleural/cirurgia , Tomografia Computadorizada por Raios X
14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(3): 511-516, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35642163

RESUMO

Objective: To establish a brain hematoma CT image segmentation method based on watershed and region-growing algorithm so as to measure hematoma volume quickly and accurately, to explore the consistency between the results of this segmentation method and those of manual segmentation, the clinical gold standard, and to compare the results of this method with the calculation of the two Tada formulas commonly used in clinical practice. Methods: The preoperative CT images of 152 patients who were treated for spontaneous cerebral hemorrhage at the Department of Neurosurgery, West China Hospital, Sichuan University between January 2018 and June 2019 were retrospectively collected. The CT images were randomly assigned, by using a random number table, to the training set, the test set and the validation set, which contained 100 patients, 22 patients and 30 patients, respectively. The labeling results of the training set and the test set were used in algorithm training and testing. Four methods, namely, manual segmentation, algorithm segmentation, i.e., segmentation calculation based on watershed and regional growth algorithm, Tada formula, i.e., the traditional Tada formula calculation, and accurate Tada formula, i.e., accurate Tada formula calculation based on 3D-Slicer, were applied on the validation set to measure the hematoma volume. The Digital Imaging and Communications in Medicine (DICOM) data of subjects meeting the selection criteria of the study were manually segmented by two experienced neurosurgeons. The hematoma segmentation model was built based on watershed algorithm and regional growth algorithm. Seed point selected by neurosurgeons was taken as the starting point of growth. Regional grayscale difference criterion combined with manual segmentation validation were adopted to determine the regional growth threshold that met the segmentation precision requirements for intracranial hematoma. Using manual segmentation as the gold standard, Bland-Altman consistency analysis was used to verify the consistency of the three other methods for measuring hematoma volume. Results: With manual segmentation as the gold standard, among the three methods of measuring hematoma volume, algorithm segmentation had the smallest percentage error, the narrowest range of difference, the highest intra-group correlation coefficient (0.987), good consistency, and the narrowest 95% limits of agreement ( LoA). The percentage error of its segmentation was not statistically significant for hematomas of different volumes. Conclusion: The segmentation method of spontaneous intracerebral hemorrhage based on watershed and regional growth algorithm shows stable measurement performance and good consistency with the clinical gold standard, which has considerable clinical significance, but it still needs further validation with more clinical samples.


Assuntos
Hematoma , Tomografia Computadorizada por Raios X , Algoritmos , Hemorragia Cerebral/diagnóstico por imagem , Hematoma/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
15.
16.
World J Emerg Surg ; 17(1): 31, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35655215

RESUMO

BACKGROUND: Emergency laparotomy (EL) has a high mortality rate. Clinically, frail patients have a poor tolerance for EL. In recent years, sarcopenia has been used as an important indicator of frailty and has received much attention. There have been five different calculation methods of psoas for computed tomography (CT) to measure sarcopenia, but lack of assessment of these calculation methods in Eastern Asian EL patients. METHODS: We conducted a 2-year retrospective cohort study of patients over 18 years of age who underwent EL in our institution. Five CT measurement values (PMI: psoas muscle index, PML3: psoas muscle to L3 vertebral body ratio, PMD: psoas muscle density, TPG: total psoas gauge, PBSA: psoas muscle to body face area ratio) were calculated to define sarcopenia. Patients with sarcopenia defined by the sex-specific lowest quartile of each measurement were compared with the rest of the cohort. The primary outcome was "ideal outcome", defined as: (1) No postoperative complications of Clavien-Dindo Grade ≥ 4; (2) No mortality within 30 days; (3) When discharged, no need for fluid resuscitation and assisted ventilation, semi-liquid diet tolerated, and able to mobilize independently. The second outcome was mortality at 30-days. Multivariate logistic regression and receiver operating characteristic (ROC) analysis were used. RESULTS: Two hundred and twenty-eight patients underwent EL met the inclusion criteria, 192 (84.2%) patients had an ideal outcome after surgery; 32 (14%) patients died within 30 days. Multivariate analysis showed that, except PMD, each calculation method of psoas was independently related to clinical outcome (ideal outcome: PML3, P < 0.001; PMI, P = 0.001; PMD, P = 0.157; TPG, P = 0.006; PBSA, P < 0.001; mortality at 30-days: PML3, P < 0.001; PMI, P = 0.002; PMD, P = 0.088; TPG, P = 0.002; PBSA, P = 0.001). In ROC analysis, the prediction model containing PML3 had the largest area under the curve (AUC) value (AUC value = 0.922 and 0.920, respectively). CONCLUSION: The sarcopenia determined by CT psoas measurements is significantly related to the clinical outcome of EL. The calculation of CT psoas measurement is suitable for application in outcome prediction of EL. In the future, it is necessary to develop a scoring tool that includes sarcopenia to evaluate the risk of EL better.


Assuntos
Laparotomia , Sarcopenia , Adolescente , Adulto , Feminino , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
17.
Sci Data ; 9(1): 264, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35654864

RESUMO

Technological advancements in X-ray imaging using bright and coherent synchrotron sources now allows the decoupling of sample size and resolution while maintaining high sensitivity to the microstructures of soft, partially dehydrated tissues. The continuous developments in multiscale X-ray imaging resulted in hierarchical phase-contrast tomography, a comprehensive approach to address the challenge of organ-scale (up to tens of centimeters) soft tissue imaging with resolution and sensitivity down to the cellular level. Using this technique, we imaged ex vivo an entire human left lung at an isotropic voxel size of 25.08 µm along with local zooms down to 6.05-6.5 µm and 2.45-2.5 µm in voxel size. The high tissue contrast offered by the fourth-generation synchrotron source at the European Synchrotron Radiation Facility reveals the complex multiscale anatomical constitution of the human lung from the macroscopic (centimeter) down to the microscopic (micrometer) scale. The dataset provides comprehensive organ-scale 3D information of the secondary pulmonary lobules and delineates the microstructure of lung nodules with unprecedented detail.


Assuntos
Pulmão , Tomografia Computadorizada por Raios X , Humanos , Pulmão/diagnóstico por imagem , Microscopia de Contraste de Fase , Síncrotrons
18.
BMC Med Imaging ; 22(1): 106, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658908

RESUMO

PURPOSE: To compare the effects of deep learning image reconstruction (DLIR) and adaptive statistical iterative reconstruction V (ASiR-V) on image quality in low-dose computed tomography (CT) of paranasal sinuses in children. METHODS: Low-dose CT scans of the paranasal sinuses in 25 pediatric patients were retrospectively evaluated. The raw data were reconstructed with three levels of DLIR (high, H; medium, M; and low, L), filtered back projection (FBP), and ASiR-V (30% and 50%). Image noise was measured in both soft tissue and bone windows, and the signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of the images were calculated. Subjective image quality at the ethmoid sinus and nasal cavity levels of the six groups of reconstructed images was assessed by two doctors using a five-point Likert scale in a double-blind manner. RESULTS: The patients' mean dose-length product and effective dose were 36.65 ± 2.44 mGy·cm and 0.17 ± 0.03 mSv, respectively. (1) Objective evaluation: 1. Soft tissue window: The difference among groups in each parameter was significant (P < 0.05). Pairwise comparisons showed that the H group' s parameters were significantly better (P < 0.05) than those of the 50% post-ASiR-V group. 2. Bone window: No significant between-group differences were found in the noise of the petrous portion of the temporal bone or its SNR or in the noise of the pterygoid processes of the sphenoids or their SNRs (P > 0.05). Significant differences were observed in the background noise and CNR (P < 0.05). As the DLIR intensity increased, image noise decreased and the CNR improved. The H group exhibited the best image quality. (2) Subjective evaluation: Scores for images of the ethmoid sinuses were not significantly different among groups (P > 0.05). Scores for images of the nasal cavity were significantly different among groups (P < 0.05) and were ranked in descending order as follows: H, M, L, 50% post-ASiR-V, 30% post-ASiR-V, and FBP. CONCLUSION: DLIR was superior to FBP and post-ASiR-V in low-dose CT scans of pediatric paranasal sinuses. At high intensity (H), DLIR provided the best reconstruction effects.


Assuntos
Aprendizado Profundo , Seios Paranasais , Algoritmos , Criança , Método Duplo-Cego , Humanos , Processamento de Imagem Assistida por Computador , Seios Paranasais/diagnóstico por imagem , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
19.
Sensors (Basel) ; 22(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35684665

RESUMO

Magnetic resonance (MR) imaging is an important computer-aided diagnosis technique with rich pathological information. The factor of physical and physiological constraint seriously affects the applicability of that technique. Thus, computed tomography (CT)-based radiotherapy is more popular on account of its imaging rapidity and environmental simplicity. Therefore, it is of great theoretical and practical significance to design a method that can construct an MR image from the corresponding CT image. In this paper, we treat MR imaging as a machine vision problem and propose a multi-conditional constraint generative adversarial network (GAN) for MR imaging from CT scan data. Considering reversibility of GAN, both generator and reverse generator are designed for MR and CT imaging, respectively, which can constrain each other and improve consistency between features of CT and MR images. In addition, we innovatively treat the real and generated MR image discrimination as object re-identification; cosine error fusing with original GAN loss is designed to enhance verisimilitude and textural features of the MR image. The experimental results with the challenging public CT-MR image dataset show distinct performance improvement over other GANs utilized in medical imaging and demonstrate the effect of our method for medical image modal transformation.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Diagnóstico por Computador , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Cintilografia , Tomografia Computadorizada por Raios X/métodos
20.
Contrast Media Mol Imaging ; 2022: 1199841, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685654

RESUMO

This study aimed to analyze the influence of artificial intelligence (AI) reconstruction algorithm on computed tomography (CT) images and the application of CT image analysis in the recovery of knee anterior cruciate ligament (ACL) sports injuries. A total of 90 patients with knee trauma were selected for enhanced CT scanning and randomly divided into three groups. Group A used the filtered back projection (FBP) reconstruction algorithm, and the tube voltage was set to 120 kV during CT scanning. Group B used the iDose4 reconstruction algorithm, and the tube voltage was set to 120 kV during CT scanning. In group C, the iDose4 reconstruction algorithm was used, and the tube voltage was set to 100 kV during CT scanning. The noise, signal-to-noise ratio (SNR), carrier-to-noise ratio (CNR), CT dose index volume (CTDI), dose length product (DLP), and effective radiation dose (ED) of the three groups of CT images were compared. The results showed that the noise of groups B and C was smaller than that of group A (P < 0.05), and the SNR and CNR of groups B and C were higher than those of group A. The images of patients in group A with the FBP reconstruction algorithm were noisy, and the boundaries were not clear. The noise of the images obtained by the iDose4 reconstruction algorithm in groups B and C was improved, and the image resolution was also higher. The agreement between arthroscopy and CT scan results was 96%. Therefore, the iterative reconstruction algorithm of iDose4 can improve the image quality. It was of important value in the diagnosis of knee ACL sports injury.


Assuntos
Traumatismos em Atletas , Algoritmos , Ligamento Cruzado Anterior , Inteligência Artificial , Traumatismos em Atletas/diagnóstico por imagem , Humanos , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...