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1.
Trends Hear ; 26: 23312165211068629, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34985356

RESUMO

A signal processing approach combining beamforming with mask-informed speech enhancement was assessed by measuring sentence recognition in listeners with mild-to-moderate hearing impairment in adverse listening conditions that simulated the output of behind-the-ear hearing aids in a noisy classroom. Two types of beamforming were compared: binaural, with the two microphones of each aid treated as a single array, and bilateral, where independent left and right beamformers were derived. Binaural beamforming produces a narrower beam, maximising improvement in signal-to-noise ratio (SNR), but eliminates the spatial diversity that is preserved in bilateral beamforming. Each beamformer type was optimised for the true target position and implemented with and without additional speech enhancement in which spectral features extracted from the beamformer output were passed to a deep neural network trained to identify time-frequency regions dominated by target speech. Additional conditions comprising binaural beamforming combined with speech enhancement implemented using Wiener filtering or modulation-domain Kalman filtering were tested in normally-hearing (NH) listeners. Both beamformer types gave substantial improvements relative to no processing, with significantly greater benefit for binaural beamforming. Performance with additional mask-informed enhancement was poorer than with beamforming alone, for both beamformer types and both listener groups. In NH listeners the addition of mask-informed enhancement produced significantly poorer performance than both other forms of enhancement, neither of which differed from the beamformer alone. In summary, the additional improvement in SNR provided by binaural beamforming appeared to outweigh loss of spatial information, while speech understanding was not further improved by the mask-informed enhancement method implemented here.

2.
J Thorac Dis ; 13(9): 5556-5571, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34659821

RESUMO

Anti-synthetase syndrome (AS) is a rare autoimmune disorder characterized by the presence of aminoacyl-transfer RNA synthetase antibodies in conjunction with clinical features such as interstitial lung disease (ILD), Raynaud's phenomenon, nonerosive arthritis, and myopathy. AS distinguishes itself from other inflammatory myopathies by its significant lung involvement and rapidly progressive interstitial lung disease (AS-ILD), therefore the management of AS-ILD requires careful clinical, serologic and radiologic assessment. Glucocorticoids are considered the mainstay of therapy; however, additional immunosuppressive agents are often required to achieve disease control. Patient prognosis is highly dependent on early diagnosis and symptom recognition as the antibody profile is thought to influence therapy response. Since progressive ILD is the leading cause of morbidity and mortality, this review will discuss the clinical approach to patient with suspected AS, with particular emphasis on diagnosis and management of AS-ILD.

3.
J Acoust Soc Am ; 149(4): 2292, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33940889

RESUMO

A conventional approach to wideband multi-source (MS) direction-of-arrival (DOA) estimation is to perform single source (SS) DOA estimation in time-frequency (TF) bins for which a SS assumption is valid. Such methods use the W-disjoint orthogonality (WDO) assumption due to the speech sparseness. As the number of sources increases, the chance of violating the WDO assumption increases. As shown in the challenging scenarios with multiple simultaneously active sources over a short period of time masking each other, it is possible for a strongly masked source (due to inconsistency of activity or quietness) to be rarely dominant in a TF bin. SS-based DOA estimators fail in the detection or accurate localization of masked sources in such scenarios. Two analytical approaches are proposed for narrowband DOA estimation based on the MS assumption in a bin in the spherical harmonic domain. In the first approach, eigenvalue decomposition is used to decompose a MS scenario into multiple SS scenarios, and a SS-based analytical DOA estimation is performed on each. The second approach analytically estimates two DOAs per bin assuming the presence of two active sources per bin. The evaluation validates the improvement to double accuracy and robustness to sensor noise compared to the baseline methods.

4.
Proc (Bayl Univ Med Cent) ; 34(3): 407-408, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33953480

RESUMO

We present a rare cause of pulmonary arterial hypertension in a 29-year-old woman with rapidly progressive and fatal hypoxia. Subsequent workup revealed classic radiological findings and pathologic confirmation of pulmonary veno-occlusive disease.

5.
Chest ; 159(1): e49-e52, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33422241

RESUMO

CASE PRESENTATION: A 55-year-old woman with COPD, heart failure with preserved ejection fraction (congestive heart failure), diabetes mellitus, and hypertension presented with baseline dyspnea at rest that had worsened over the last week. She reported associated runny nose, congestion, and cough productive of green sputum. She smoked six cigarettes per day and denied alcohol, drugs, or occupational exposure. She was admitted and initiated on treatment for acute exacerbation of COPD; however, her condition did not improve with steroid, ceftriaxone, and nebulized albuterol and budesonide treatments. She had been diagnosed with asthma and COPD without ever undergoing pulmonary function testing. She presented 11 times to the ED with six hospital admissions in the last 1.5 years for worsening dyspnea at rest, wheezing, and lower extremity edema deemed secondary to exacerbation of her COPD or congestive heart failure. She reported medication compliance, which included fluticasone-vilanterol, tiotropium bromide, and furosemide. She repeatedly demonstrated mild vascular congestion on imaging without hyperinflation, a normal to mildly elevated brain natriuretic peptide (<10 to 200 pg/mL), and dyspnea without hypoxia. She was treated normally for both COPD and congestive heart failure exacerbations simultaneously with methylprednisolone, albuterol, and furosemide with rapid improvement over the course of 1 to 2 days. No significant improvement was noted with steroid therapy, despite receiving them as an inpatient and outpatient. At the time of discharge, her symptoms would be at her baseline.


Assuntos
Neoplasias Brônquicas/complicações , Neoplasias Brônquicas/diagnóstico , Dispneia/etiologia , Tumor de Células Granulares/complicações , Tumor de Células Granulares/diagnóstico , Doença Pulmonar Obstrutiva Crônica/complicações , Neoplasias Brônquicas/terapia , Feminino , Tumor de Células Granulares/terapia , Humanos , Pessoa de Meia-Idade
6.
Radiographics ; 40(6): 1528-1553, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33001784

RESUMO

Transcatheter mitral valve replacement (TMVR) is a catheter-based interventional technique for treating mitral valve disease in patients who are at high risk for open mitral valve surgery and with unfavorable anatomy for minimally invasive edge-to-edge transcatheter mitral valve repair. There are several TMVR devices with different anchoring mechanisms, delivered by either transapical or transseptal approaches. Transthoracic echocardiography is the first-line imaging modality used for characterization and quantification of mitral valve disorders. CT is complementary to echocardiography and has several advantages, including high isotropic spatial resolution, good temporal resolution, large field of view, multiplanar reconstruction capabilities, and rapid turnaround time. CT is essential for multiple aspects of preprocedural planning. Accurate and reproducible techniques to prescribe the mitral annulus at CT have been described from which important measurements such as the area, perimeter, trigone-trigone distance, intercommissural distance, and septolateral distance are obtained. The neo-left ventricular outflow tract (LVOT) can be simulated by placing a virtual prosthesis in the CT data to predict the risk of TMVR-induced LVOT obstruction. The anatomy of the landing zone and subvalvular apparatus as well as the relationship of the virtual device to adjacent structures such as the coronary sinus and left circumflex coronary artery can be evaluated. CT also stimulates procedural fluoroscopic angles. CT can be used to evaluate the chest wall for transapical access and the atrial septum for transseptal access. Follow-up CT is useful in identifying complications such as LVOT obstruction, paravalvular leak, pseudoaneurysm, and valve embolization. Online supplemental material is available for this article. ©RSNA, 2020.


Assuntos
Cateterismo Cardíaco , Implante de Prótese de Valva Cardíaca/métodos , Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral/cirurgia , Estenose da Valva Mitral/cirurgia , Tomografia Computadorizada por Raios X , Humanos , Insuficiência da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem
7.
BMJ Open Respir Res ; 7(1)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32928787

RESUMO

The SARS-CoV-2 can lead to severe illness with COVID-19. Outcomes of patients requiring mechanical ventilation are poor. Awake proning in COVID-19 improves oxygenation, but on data clinical outcomes is limited. This single-centre retrospective study aimed to assess whether successful awake proning of patients with COVID-19, requiring respiratory support (continuous positive airways pressure (CPAP) or high-flow nasal oxygen (HFNO)) on a respiratory high-dependency unit (HDU), is associated with improved outcomes. HDU care included awake proning by respiratory physiotherapists. Of 565 patients admitted with COVID-19, 71 (12.6%) were managed on the respiratory HDU, with 48 of these (67.6%) requiring respiratory support. Patients managed with CPAP alone 22/48 (45.8%) were significantly less likely to die than patients who required transfer onto HFNO 26/48 (54.2%): CPAP mortality 36.4%; HFNO mortality 69.2%, (p=0.023); however, multivariate analysis demonstrated that increasing age and the inability to awake prone were the only independent predictors of COVID-19 mortality. The mortality of patients with COVID-19 requiring respiratory support is considerable. Data from our cohort managed on HDU show that CPAP and awake proning are possible in a selected population of COVID-19, and may be useful. Further prospective studies are required.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Infecções por Coronavirus/terapia , Oxigenoterapia/métodos , Posicionamento do Paciente/métodos , Pneumonia Viral/terapia , Decúbito Ventral , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , COVID-19 , Infecções por Coronavirus/mortalidade , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ventilação não Invasiva/métodos , Razão de Chances , Pandemias , Pneumonia Viral/mortalidade , Estudos Retrospectivos , SARS-CoV-2 , Resultado do Tratamento , Reino Unido , Vigília
8.
BMJ Case Rep ; 13(3)2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32217660

RESUMO

A 72-year-old woman was referred with incidentally detected multiple lung nodules, one of which was identified as 18F-fluorodeoxyglucose (FDG)-avid on positron emission tomography. Extensive workup followed, including numerous radiographs, surveillance scans and a CT-guided biopsy which demonstrated chronic inflammation only. Following a wedge-resection, a diagnosis of pulmonary hyalinising granuloma (PHG) was made. PHG is a cause of FDG-avid single or multiple pulmonary nodules and can mimic lung cancer or metastatic disease radiologically. The diagnosis is often difficult to make with minimally invasive techniques such as needle-guided biopsies which do not tend to yield the diagnosis and requires surgical resection for definitive diagnosis and exclusion of malignancy.


Assuntos
Granuloma/diagnóstico por imagem , Granuloma/cirurgia , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/cirurgia , Idoso , Diagnóstico Diferencial , Feminino , Fluordesoxiglucose F18 , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
9.
Cardiovasc Pathol ; 46: 107175, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31951962

RESUMO

Aortic syphilis today is infrequently diagnosed clinically. Described herein are findings in 5 women who had resection of a fusiform aneurysm of the tubular portion of ascending aorta, and examination of the wall of the aneurysm disclosed classic features of aortic syphilis. The 5 patients were among 36 who had ascending aortic operations at Baylor University Medical Center in Dallas in 2018 and early 2019. Syphilitic aneurysm in each spared the sinus portion and involved diffusely the tubular portion of ascending aorta, beginning at the sinotubular junction. The aneurysmal wall was thicker than normal because of thickening of both intima and adventitia. The latter contained foci of lymphocytes and plasmacytes and thickened and narrowed vasa vasora. The media was disrupted by fibrous scars, which weakened the integrity of the aorta. Aortitis of the tubular portion of ascending aorta in syphilis is a diffuse process, but often is mistakenly called "atherosclerosis" which, when present in this portion of aorta, can be extensive but is focal. Aortic syphilis is important to diagnose so that patients can receive antibiotic therapy to delay, prevent, or treat neurosyphilis, a common accompaniment of aortic syphilis.


Assuntos
Aneurisma Infectado/microbiologia , Aorta/microbiologia , Aneurisma Aórtico/microbiologia , Aortite/microbiologia , Sífilis Cardiovascular/microbiologia , Idoso , Aneurisma Infectado/diagnóstico por imagem , Aneurisma Infectado/patologia , Aneurisma Infectado/cirurgia , Antibacterianos/uso terapêutico , Aorta/diagnóstico por imagem , Aorta/patologia , Aorta/cirurgia , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/patologia , Aneurisma Aórtico/cirurgia , Aortite/diagnóstico por imagem , Aortite/patologia , Aortite/cirurgia , Aortografia , Biópsia , Implante de Prótese Vascular , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Fatores de Risco , Sífilis Cardiovascular/diagnóstico por imagem , Sífilis Cardiovascular/patologia , Sífilis Cardiovascular/cirurgia , Texas , Resultado do Tratamento
10.
Proc (Bayl Univ Med Cent) ; 34(1): 178-179, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33456192

RESUMO

Coronavirus disease 2019 (COVID-19) initiates a hypercoagulable state and causes thrombotic complications. A presentation of multiple thromboembolic events without an underlying source should raise suspicion for COVID-19 hypercoagulability. We describe a patient with an ascending aortic thrombus resulting in multiple emboli treated by multiple modalities.

12.
J Acoust Soc Am ; 145(5): 2971, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31153329

RESUMO

The effect of personalized microphone array calibration on the performance of hearing aid beamformers under noisy reverberant conditions is studied. The study makes use of a new, publicly available, database containing acoustic transfer function measurements from 29 loudspeakers arranged on a sphere to a pair of behind-the-ear hearing aids in a listening room when worn by 27 males, 14 females, and 4 mannequins. Bilateral and binaural beamformers are designed using each participant's hearing aid head-related impulse responses (HAHRIRs). The performance of these personalized beamformers is compared to that of mismatched beamformers, where the HAHRIR used for the design does not belong to the individual for whom performance is measured. The case where the mismatched HAHRIR is that of a mannequin is of particular interest since it represents current practice in commercially available hearing aids. The benefit of personalized beamforming is assessed using an intrusive binaural speech intelligibility metric and in a matrix speech intelligibility test. For binaural beamforming, both measures demonstrate a statistically signficant (p < 0.05) benefit of personalization. The benefit varies substantially between individuals with some predicted to benefit by as much as 1.5 dB.


Assuntos
Limiar Auditivo/fisiologia , Localização de Som/fisiologia , Inteligibilidade da Fala/fisiologia , Percepção da Fala/fisiologia , Estimulação Acústica/métodos , Implante Coclear/métodos , Implantes Cocleares/efeitos adversos , Feminino , Humanos , Masculino
13.
Radiographics ; 39(4): 932-956, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31150303

RESUMO

Replacement with a prosthetic heart valve (PHV) remains the definitive surgical procedure for management of severe cardiac valve disease. PHV dysfunction is uncommon but can be a life-threatening condition. The broad hemodynamic and pathophysiologic manifestations of PHV dysfunction are stenosis, regurgitation, and a stuck leaflet. Specific structural abnormalities that cause PHV dysfunction include prosthetic valve-patient mismatch, structural failure, valve calcification, dehiscence, paravalvular leak, infective endocarditis, abscess, pseudoaneurysm, abnormal connections, thrombus, hypoattenuating leaflet thickening, and pannus. Multiple imaging modalities are available for evaluating a PHV and its dysfunction. Transthoracic echocardiography is often the first-line imaging modality, with additional modalities such as transesophageal echocardiography, CT, MRI, cine fluoroscopy, and nuclear medicine used for further characterization and establishing a specific cause. The authors review PHVs and the role of imaging modalities in evaluation of PHV dysfunction and illustrate the imaging appearances of different complications. Online supplemental material is available for this article. ©RSNA, 2019.


Assuntos
Doenças das Valvas Cardíacas/diagnóstico por imagem , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas/efeitos adversos , Complicações Pós-Operatórias/diagnóstico por imagem , Aneurisma Dissecante/diagnóstico por imagem , Falso Aneurisma/diagnóstico por imagem , Bioprótese/efeitos adversos , Calcinose/diagnóstico por imagem , Cinerradiografia/métodos , Constrição Patológica , Ecocardiografia/métodos , Endocardite/diagnóstico por imagem , Doenças das Valvas Cardíacas/etiologia , Doenças das Valvas Cardíacas/fisiopatologia , Hemodinâmica , Humanos , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Complicações Pós-Operatórias/etiologia , Desenho de Prótese , Falha de Prótese , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Deiscência da Ferida Operatória/diagnóstico por imagem
14.
Int J Cardiovasc Imaging ; 35(8): 1509-1524, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31049753

RESUMO

Multi-energy computed tomography (MECT) refers to acquisition of CT data at multiple energy levels (typically two levels) using different technologies such as dual-source, dual-layer and rapid tube voltage switching. In addition to conventional/routine diagnostic images, MECT provides additional image sets including iodine maps, virtual non-contrast images, and virtual monoenergetic images. These image sets provide tissue/material characterization beyond what is possible with conventional CT. MECT provides invaluable additional information in the evaluation of pulmonary vasculature, primarily by the assessment of pulmonary perfusion. This functional information provided by the MECT is complementary to the morphological information from a conventional CT angiography. In this article, we review the technique and applications of MECT in the evaluation of pulmonary vasculature.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Hemodinâmica , Hipertensão Pulmonar/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Imagem de Perfusão/métodos , Artéria Pulmonar/diagnóstico por imagem , Circulação Pulmonar , Embolia Pulmonar/diagnóstico por imagem , Humanos , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/terapia , Valor Preditivo dos Testes , Prognóstico , Artéria Pulmonar/fisiopatologia , Embolia Pulmonar/fisiopatologia , Embolia Pulmonar/terapia , Interpretação de Imagem Radiográfica Assistida por Computador
15.
J Acoust Soc Am ; 146(6): 4592, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31893703

RESUMO

A conventional approach to wideband multi-source (MS) direction-of-arrival (DOA) estimation is to perform single source (SS) DOA estimation in time-frequency (TF) bins for which a SS assumption is valid. The typical SS-validity confidence metrics analyse the validity of the SS assumption over a fixed-size TF region local to the TF bin. The performance of such methods degrades as the number of simultaneously active sources increases due to the associated decrease in the size of the TF regions where the SS assumption is valid. A SS-validity confidence metric is proposed that exploits a dynamic MS assumption over relatively larger TF regions. The proposed metric first clusters the initial DOA estimates (one per TF bin) and then uses the members' spatial consistency as well as its cluster's spread to weight each TF bin. Distance-based and density-based clustering are employed as two alternative approaches for clustering DOAs. A noise-robust density-based clustering is also used in an evolutionary framework to propose a method for source counting and source direction estimation. The evaluation results based on simulations and also with real recordings show that the proposed weighting strategy significantly improves the accuracy of source counting and MS DOA estimation compared to the state-of-the-art.

16.
Radiol Clin North Am ; 57(1): 45-55, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30454816

RESUMO

This article reviews the imaging manifestations of acute myocardial infarction (MI) on computed tomography (CT) accompanied by case examples and illustrations. This is preceded by a review of the pathophysiology of MI (acute and chronic), a summary of its clinical presentation, and a brief synopsis of the technical aspects of cardiac CT. Several examples of the appearance of acute MI and its complications are shown on routine and cardiac tailored CT, and a sample of the latest advances in imaging technique, including dual-energy CT, are introduced.


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Biomarcadores/sangue , Dor no Peito/diagnóstico por imagem , Meios de Contraste , Angiografia Coronária , Diagnóstico Diferencial , Eletrocardiografia , Humanos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/fisiopatologia
17.
Radiol Clin North Am ; 57(1): 57-65, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30454817

RESUMO

This article reviews the imaging manifestations of chronic myocardial infarction (MI) on computed tomography (CT) and the common mimickers of MI, clinically and on imaging. Several examples of the appearance of chronic MI, its complications, and mimickers of MI are shown on both routine and cardiac CT.


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Doença Crônica , Diagnóstico Diferencial , Humanos , Infarto do Miocárdio/complicações , Prognóstico
18.
Cardiovasc Diagn Ther ; 8(3): 225-243, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30057872

RESUMO

Imaging plays an important role in the evaluation and management of acute pulmonary embolism (PE). Computed tomography (CT) pulmonary angiography (CTPA) is the current standard of care and provides accurate diagnosis with rapid turnaround time. CT also provides information on other potential causes of acute chest pain. With dual-energy CT, lung perfusion abnormalities can also be detected and quantified. Chest radiograph has limited utility, occasionally showing findings of PE or infarction, but is useful in evaluating other potential causes of chest pain. Ventilation-perfusion (VQ) scan demonstrates ventilation-perfusion mismatches in these patients, with several classification schemes, typically ranging from normal to high. Magnetic resonance imaging (MRI) also provides accurate diagnosis, but is available in only specialized centers and requires higher levels of expertise. Catheter pulmonary angiography is no longer used for diagnosis and is used only for interventional management. Echocardiography is used for risk stratification of these patients. In this article, we review the role of imaging in the evaluation of acute PE.

19.
Clin Chest Med ; 39(1): 271-280, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29433722

RESUMO

Much has changed since the last review of interventional pulmonology (IP) published in this Clinics series. The rate of development of new techniques and their complexities require IP physicians to be constantly maintaining and updating their skill set. International agreed training pathways help ensure that the interventionalists of the present and future have the required knowledge of anatomy, manual dexterity, and clinical judgment to keep up with the continuing advances that are constantly expanding IP's diagnostic and therapeutic boundaries. IP remains one of the most desirable subspecialities in pulmonology, and the technologic advances make the future an exciting one.


Assuntos
Broncoscopia/métodos , Pneumologia , Humanos
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