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1.
Sci Rep ; 10(1): 15364, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958781

RESUMO

Currently, we witness the severe spread of the pandemic of the new Corona virus, COVID-19, which causes dangerous symptoms to humans and animals, its complications may lead to death. Although convolutional neural networks (CNNs) is considered the current state-of-the-art image classification technique, it needs massive computational cost for deployment and training. In this paper, we propose an improved hybrid classification approach for COVID-19 images by combining the strengths of CNNs (using a powerful architecture called Inception) to extract features and a swarm-based feature selection algorithm (Marine Predators Algorithm) to select the most relevant features. A combination of fractional-order and marine predators algorithm (FO-MPA) is considered an integration among a robust tool in mathematics named fractional-order calculus (FO). The proposed approach was evaluated on two public COVID-19 X-ray datasets which achieves both high performance and reduction of computational complexity. The two datasets consist of X-ray COVID-19 images by international Cardiothoracic radiologist, researchers and others published on Kaggle. The proposed approach selected successfully 130 and 86 out of 51 K features extracted by inception from dataset 1 and dataset 2, while improving classification accuracy at the same time. The results are the best achieved on these datasets when compared to a set of recent feature selection algorithms. By achieving 98.7%, 98.2% and 99.6%, 99% of classification accuracy and F-Score for dataset 1 and dataset 2, respectively, the proposed approach outperforms several CNNs and all recent works on COVID-19 images.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/diagnóstico , Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/diagnóstico , Algoritmos , Betacoronavirus , Aprendizado Profundo , Humanos , Redes Neurais de Computação , Pandemias , Raios X
2.
Curr Rheumatol Rep ; 22(10): 75, 2020 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-32924089

RESUMO

PURPOSE OF REVIEW: Provide the most recent updates on the epidemiology, pathogenesis, and treatment advances in Kawasaki disease. RECENT FINDINGS: Treatment advances in complex, IVIG-refractory cases of Kawasaki disease. Multisystem inflammatory syndrome, a newly reported inflammatory condition with Kawasaki-like features and an association with the 2019 Coronavirus (COVID-19). Kawasaki disease (KD) is a rare systemic inflammatory disease that predominately affects children less than 5 years of age. Pathogenesis of KD remains unknown; the leading theory is that an unknown stimulus triggers an immune-mediated inflammatory cascade in a genetically susceptible child. Classic KD is a clinical diagnosis based on set criteria and excluding other similar clinical entities. Patients who do not fulfill complete diagnostic criteria for KD are often referred to as atypical (or incomplete) KD. The most feared complication of KD is coronary artery abnormality development, and patients with atypical KD are also at risk. Administration of intravenous immunoglobulin (IVIG) and aspirin has greatly reduced the incidence of coronary lesions in affected children. Several other immune-modulating therapies have recently been utilized in complex or refractory cases.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Diagnóstico por Imagem/métodos , Fatores Imunológicos/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/complicações , Pandemias , Pneumonia Viral/complicações , Infecções por Coronavirus/epidemiologia , Humanos , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/terapia , Pneumonia Viral/epidemiologia
3.
Pediatr Clin North Am ; 67(5): 973-993, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32888693

RESUMO

This article aims to summarize some of the key advances in congenital interventional cardiology over the past few years, from novel imaging technologies, such as virtual reality, fusion imaging, and 3-dimensional printed models, to newly available devices and techniques to facilitate complex procedures including percutaneous pulmonary valve replacement and hybrid procedures. It is an exciting time for the field, with rapid development of techniques, devices, and imaging tools that allow a minimally invasive approach for many congenital cardiac defects with progressively less radiation and contrast doses.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Cardiologia/tendências , Diagnóstico por Imagem/métodos , Cardiopatias Congênitas/cirurgia , Cirurgia Assistida por Computador/tendências , Humanos
4.
Curr Opin Ophthalmol ; 31(5): 303-311, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32740061

RESUMO

PURPOSE OF REVIEW: As artificial intelligence continues to develop new applications in ophthalmic image recognition, we provide here an introduction for ophthalmologists and a primer on the mechanisms of deep learning systems. RECENT FINDINGS: Deep learning has lent itself to the automated interpretation of various retinal imaging modalities, including fundus photography and optical coherence tomography. Convolutional neural networks (CNN) represent the primary class of deep neural networks applied to these image analyses. These have been configured to aid in the detection of diabetes retinopathy, AMD, retinal detachment, glaucoma, and ROP, among other ocular disorders. Predictive models for retinal disease prognosis and treatment are also being validated. SUMMARY: Deep learning systems have begun to demonstrate a reliable level of diagnostic accuracy equal or better to human graders for narrow image recognition tasks. However, challenges regarding the use of deep learning systems in ophthalmology remain. These include trust of unsupervised learning systems and the limited ability to recognize broad ranges of disorders.


Assuntos
Aprendizado Profundo , Diagnóstico por Imagem/métodos , Oftalmopatias/diagnóstico , Interpretação de Imagem Assistida por Computador/métodos , Oftalmologistas , Humanos , Redes Neurais de Computação
5.
Radiol Clin North Am ; 58(5): 897-907, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32792122

RESUMO

Most renal masses are benign cysts; a subset are malignant. Most renal masses are incidental findings. Evaluation of renal cysts has evolved with updates to the Bosniak classification system and other guidelines. The Bosniak classification provides detailed definitions and extends the system from computed tomography to MR imaging. This article provides a simple approach to the evaluation of cystic or potentially cystic renal masses. The radiologist is central to this process. Key elements include confirming that a renal lesion is cystic and not solid, determining the need for further characterization by imaging, and judicious application of the Bosniak classification system.


Assuntos
Diagnóstico por Imagem/métodos , Doenças Renais Císticas/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Rim/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos
6.
Radiol Clin North Am ; 58(5): 909-923, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32792123

RESUMO

Acute pyelonephritis is a bacterial infection of the renal parenchyma and collecting system. Diagnosis is based on clinical findings of fever, flank pain, and urinary tract infection. Computed tomography findings include renal enlargement with wedge-shaped heterogeneous areas of decreased enhancement, known as a "striated nephrogram." Imaging is primarily used to diagnose complications such as emphysematous pyelonephritis, renal abscess, and pyonephrosis. Chronic pyelonephritis can have varying appearances on imaging ranging from xanthogranulomatous pyelonephritis or, in extreme cases, renal replacement lipomatosis.


Assuntos
Diagnóstico por Imagem/métodos , Nefropatias/diagnóstico por imagem , Pielonefrite/diagnóstico por imagem , Infecções Urinárias/diagnóstico por imagem , Humanos , Infecções/diagnóstico por imagem , Rim/diagnóstico por imagem , Imagem por Ressonância Magnética , Radiografia , Tomografia Computadorizada por Raios X , Ultrassonografia , Sistema Urinário/diagnóstico por imagem
7.
Radiol Clin North Am ; 58(5): 951-963, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32792126

RESUMO

Up to 8% of renal cancers are thought to have a hereditary component. Several hereditary renal cancer syndromes have been identified over the last few decades. It is important for the radiologist to be aware of findings associated with hereditary renal cancer syndromes to detect tumors early, enroll patients in appropriate surveillance programs, and improve outcomes for the patient and affected family members. This review discusses from a radiologist's perspective well-known hereditary renal cancer syndromes and emerging genetic mutations associated with renal cancer that are less well characterized, focusing on imaging features and known associations.


Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Diagnóstico por Imagem/métodos , Neoplasias Renais/diagnóstico por imagem , Síndromes Neoplásicas Hereditárias/diagnóstico por imagem , Esclerose Tuberosa/diagnóstico por imagem , Doença de von Hippel-Lindau/diagnóstico por imagem , Humanos , Rim/diagnóstico por imagem , Imagem por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
8.
Radiol Clin North Am ; 58(5): 981-993, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32792128

RESUMO

Based on Surveillance, Epidemiology, and End Results studies, most renal cancers are low grade and slow growing. Long-term, single-center studies show excellent outcomes for T1a renal cell carcinoma (RCC), comparable to partial nephrectomy without affecting renal function and with much lower rates of complications. However, there are no multicenter randomized controlled trials of multiple ablative modalities or comparison with partial nephrectomy, and most studies are single-arm observational studies with short-term and intermediate follow-up. For treatment of stage T1a RCC, percutaneous TA is an effective alternative to surgery with preservation of renal function, low risk, and comparable overall and disease-specific survival.


Assuntos
Carcinoma de Células Renais/cirurgia , Ablação por Cateter/métodos , Neoplasias Renais/cirurgia , Diagnóstico por Imagem/métodos , Humanos , Rim/diagnóstico por imagem , Rim/cirurgia , Neoplasias Renais/diagnóstico por imagem , Resultado do Tratamento
11.
Life Sci ; 258: 118206, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32758623

RESUMO

Scientists are looking for new therapies to cope with the rise in cancer worldwide. Since cancer cells overexpress peptide receptors and owing to small size, easy uptake by tumor cells, easy preparation, and with no toxicity, the use of radiolabeled peptides with high specificity and affinity for accurate imaging and therapy has attracted much attention. To develop an ideal imaging or treatment radiolabeled peptide, there are some aspects in the components of radiolabeled peptide including radionuclide, peptide, chelator, and spacer that should be considered. Some peptides, including somatostatin, RGD, neurotensin, bombesin, exendin, vasoactive intestinal peptide, and gastrin are currently under (pre)clinical investigations. Today, nanoparticles are suitable tools for targeting peptide for molecular imaging and therapy of tumors with low toxicity. This paper presents some essential aspects in developing a valuable radiolabeled peptide and some radiolabeled peptides with regard to their applications in tumor imaging and therapy in pre-clinical and clinical phases.


Assuntos
Diagnóstico por Imagem/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Fragmentos de Peptídeos/metabolismo , Compostos Radiofarmacêuticos/metabolismo , Animais , Diagnóstico por Imagem/tendências , Humanos , Mediadores da Inflamação/metabolismo
13.
Lab Chip ; 20(18): 3302-3309, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32743622

RESUMO

To detect the presence of antibodies in blood against SARS-CoV-2 in a highly sensitive and specific manner, here we describe a robust, inexpensive ($200), 3D-printable portable imaging platform (TinyArray imager) that can be deployed immediately in areas with minimal infrastructure to read coronavirus antigen microarrays (CoVAMs) that contain a panel of antigens from SARS-CoV-2, SARS-1, MERS, and other respiratory viruses. Application includes basic laboratories and makeshift field clinics where a few drops of blood from a finger prick could be rapidly tested in parallel for the presence of antibodies to SARS-CoV-2 with a test turnaround time of only 2-4 h. To evaluate our imaging device, we probed and imaged coronavirus microarrays with COVID-19-positive and negative sera and achieved a performance on par with a commercial microarray reader 100× more expensive than our imaging device. This work will enable large scale serosurveillance, which can play an important role in the months and years to come to implement efficient containment and mitigation measures, as well as help develop therapeutics and vaccines to treat and prevent the spread of COVID-19.


Assuntos
Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Diagnóstico por Imagem/instrumentação , Diagnóstico por Imagem/métodos , Análise em Microsséries/métodos , Pneumonia Viral/diagnóstico , Infecções por Coronavirus/imunologia , Humanos , Microscopia , Pandemias , Pneumonia Viral/imunologia , Impressão Tridimensional , Vigilância em Saúde Pública , Pontos Quânticos
15.
Anticancer Res ; 40(7): 3915-3924, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32620632

RESUMO

BACKGROUND: Wire-guided localization (WGL) has been the mainstay for localizing non-palpable breast lesions before excision. Due to its limitations, various wireless alternatives have been developed. In this prospective study, we evaluate the role of radiation-free wireless localization using the SAVI SCOUT® localization at a European centre. PATIENTS AND METHODS: This technique was evaluated in a prospective cohort of 20 patients. The evaluation focused on clinical and pathological parameters in addition to patient and physician acceptance. RESULTS: SAVI SCOUT reflectors (n=23) were deployed to localize 22 occult breast lesions and one axillary lymph node in 20 patients. The mean deployment duration was 5.6 min, with a mean distance from the lesion of 0.6 mm. The migration rate was 0% and the mean identification and retrieval time was 25.1 min. In patients undergoing therapeutic excision for malignancy (n=17), only one (5.9%) required reoperation for positive surgical margins. Radiologists and surgeons rated the technique as better than WGL and patient satisfaction was high. CONCLUSION: Our study demonstrates that wireless localization using SAVI SCOUT® is an effective and time-efficient alternative to WGL with excellent physician and patient acceptance.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Diagnóstico por Imagem/métodos , Adulto , Idoso , Neoplasias da Mama/cirurgia , Diagnóstico por Imagem/instrumentação , Feminino , Humanos , Raios Infravermelhos , Mamografia/instrumentação , Mamografia/métodos , Pessoa de Meia-Idade , Radar
16.
Eur Respir J ; 56(2)2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32616598
17.
Pediatr Radiol ; 50(9): 1313-1323, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32621013

RESUMO

During the outbreak of the COVID-19 pandemic, guidelines have been issued by international, national and local authorities to address management and the need for preparedness. Children with COVID-19 differ from adults in that they are less often and less severely affected. Additional precautions required in the management of children address their increased radiosensitivity, need for accompanying carers, and methods for dealing with children in a mixed adult-paediatric institution. In this guidance document, our aim is to define a pragmatic strategy for imaging children with an emphasis on proven or suspected COVID-19 cases. Children suspected of COVID-19 should not be imaged routinely. Imaging should be performed only when expected to alter patient management, depending on symptoms, preexisting conditions and clinical evolution. In order to prevent disease transmission, it is important to manage the inpatient caseload effectively by triaging children and carers outside the hospital, re-scheduling nonurgent elective procedures and managing symptomatic children and carers as COVID-19 positive until proven otherwise. Within the imaging department one should consider conducting portable examinations with COVID-19 machines or arranging dedicated COVID-19 paediatric imaging sessions and performing routine nasopharyngeal swab testing before imaging under general anaesthesia. Finally, regular personal hygiene, appropriate usage of personal protective equipment, awareness of which procedures are considered aerosol generating and information on how to best disinfect imaging machinery after examinations should be highlighted to all staff members.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Diagnóstico por Imagem/métodos , Controle de Infecções/métodos , Pandemias/prevenção & controle , Pediatria/métodos , Pneumonia Viral/prevenção & controle , Adolescente , Criança , Pré-Escolar , Humanos , Lactente
18.
Nat Commun ; 11(1): 3673, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699250

RESUMO

Causal reasoning can shed new light on the major challenges in machine learning for medical imaging: scarcity of high-quality annotated data and mismatch between the development dataset and the target environment. A causal perspective on these issues allows decisions about data collection, annotation, preprocessing, and learning strategies to be made and scrutinized more transparently, while providing a detailed categorisation of potential biases and mitigation techniques. Along with worked clinical examples, we highlight the importance of establishing the causal relationship between images and their annotations, and offer step-by-step recommendations for future studies.


Assuntos
Diagnóstico por Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Causalidade , Humanos
19.
J Am Coll Radiol ; 17(9): 1086-1095, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32717183

RESUMO

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic resulted in significant loss of radiologic volume as a result of shelter-at-home mandates and delay of non-time-sensitive imaging studies to preserve capacity for the pandemic. We analyze the volume-related impact of the COVID-19 pandemic on six academic medical systems (AMSs), three in high COVID-19 surge (high-surge) and three in low COVID-19 surge (low-surge) regions, and a large national private practice coalition. We sought to assess adaptations, risks of actions, and lessons learned. METHODS: Percent change of 2020 volume per week was compared with the corresponding 2019 volume calculated for each of the 14 imaging modalities and overall total, outpatient, emergency, and inpatient studies in high-surge AMSs and low-surge AMSs and the practice coalition. RESULTS: Steep examination volume drops occurred during week 11, with slow recovery starting week 17. The lowest total AMS volume drop was 40% compared with the same period the previous year, and the largest was 70%. The greatest decreases were seen with screening mammography and dual-energy x-ray absorptiometry scans, and the smallest decreases were seen with PET/CT, x-ray, and interventional radiology. Inpatient volume was least impacted compared with outpatient or emergency imaging. CONCLUSION: Large percentage drops in volume were seen from weeks 11 through 17, were seen with screening studies, and were larger for the high-surge AMSs than for the low-surge AMSs. The lowest drops in volume were seen with modalities in which delays in imaging had greater perceived adverse consequences.


Assuntos
Infecções por Coronavirus/prevenção & controle , Diagnóstico por Imagem/estatística & dados numéricos , Controle de Infecções/organização & administração , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Radiologia/estatística & dados numéricos , Infecções por Coronavirus/epidemiologia , Diagnóstico por Imagem/métodos , Feminino , Previsões , Humanos , Incidência , Aprendizagem , Masculino , Pandemias/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Radiologia/tendências , Medição de Risco , Estados Unidos
20.
Aging Clin Exp Res ; 32(9): 1889-1895, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32638344

RESUMO

BACKGROUND: The potential differences between a clinical diagnosis of coronavirus disease 2019 (COVID-19) (i.e., symptoms without positive virus test) and a microbiological diagnosis (i.e., positive virus test results) of COVID-19 are not known. AIMS: This study explored the differences between the two types of COVID-19 diagnosis among older patients in terms of clinical characteristics and outcomes. METHODS: A total of 244 inpatients aged ≥ 60 years with COVID-19 were included in this study, of whom 52 were clinically diagnosed and 192 were microbiologically diagnosed. Clinical and laboratory data on hospital admission and outcomes (discharged or died in hospital) of all patients were retrieved from medical records retrospectively. Patients who met the criteria for clinical diagnosis with negative virus test results were assigned to the clinical diagnosis group, whereas those with positive virus test results were assigned to the microbiological diagnosis group. After univariate analyses, two propensity score analyses [i.e., covariate adjustment using propensity score (CAPS) and propensity score matching (PSM)] were conducted to control bias. RESULTS: The clinical and microbiological diagnosis groups demonstrated significant differences in outcomes and in the majority of laboratory findings. After propensity score analyses, many differences between the two groups disappeared and the rate of mortality had no statistically significant difference (P = 0.318 and 0.828 for CAPS and PSM, respectively). CONCLUSIONS: Patients with similar signs, symptoms, and laboratory and imaging findings as confirmed COVID-19 cases may have a similar mortality risk, regardless of the virus test results, and require timely intervention to reduce their mortality.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico , Infecções por Coronavirus , Diagnóstico por Imagem , Pandemias , Pneumonia Viral , Avaliação de Sintomas , Idoso , China/epidemiologia , Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/estatística & dados numéricos , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/terapia , Correlação de Dados , Diagnóstico por Imagem/métodos , Diagnóstico por Imagem/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Pneumonia Viral/diagnóstico , Pneumonia Viral/mortalidade , Pneumonia Viral/fisiopatologia , Pneumonia Viral/terapia , Estudos Retrospectivos , Medição de Risco , Avaliação de Sintomas/métodos , Avaliação de Sintomas/estatística & dados numéricos
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