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1.
J Comput Assist Tomogr ; 47(1): 50-57, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36571247

RESUMO

OBJECTIVE: This study aimed to determine the prevalence of axillary and subpectoral (SP) lymph nodes after ipsilateral COVID-19 vaccine administration on chest computed tomography (CT). METHODS: Subjects with chest CTs between 2 and 25 days after a first or second vaccine dose, December 15, 2020, to February 12, 2021, were included. Orthogonal measures of the largest axillary and SP nodes were recorded by 2 readers blinded to vaccine administration and clinical details. A mean nodal diameter discrepancy of ≥6 mm between contralateral stations was considered positive for asymmetry. Correlation with the side of vaccination, using a Spearman rank correlation, was performed on the full cohort and after excluding patients with diseases associated with adenopathy. RESULTS: Of the 138 subjects (81 women, 57 men; mean [SD] age, 74.4 ± 11.7 years), 48 (35%) had asymmetrically enlarged axillary and/or SP lymph nodes, 42 (30%) had ipsilateral, and 6 (4%) had contralateral to vaccination ( P = 0.003). Exclusion of 29 subjects with conditions associated with adenopathy showed almost identical correlation, with asymmetric nodes in 32 of 109 (29%) ipsilateral and in 5 of 109 (5%) contralateral to vaccination ( P = 0.002). CONCLUSIONS: Axillary and/or SP lymph nodes ipsilateral to vaccine administration represents a clinical conundrum. Asymmetric nodes were detected at CT in 30% of subjects overall and 29% of subjects without conditions associated with adenopathy, approximately double the prevalence rate reported to the Centers for Disease Control and Prevention by vaccine manufacturers. When interpreting examinations correlation with vaccine administration timing and site is important for pragmatic management.


Assuntos
COVID-19 , Linfadenopatia , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , SARS-CoV-2 , Vacinas contra COVID-19 , Prevalência , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/patologia , Tomografia Computadorizada por Raios X , Linfadenopatia/diagnóstico por imagem , Linfadenopatia/epidemiologia , Linfadenopatia/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Vacinação
2.
Radiology ; 297(2): E252-E262, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32614258

RESUMO

Background A high number of patients with coronavirus disease 2019 (COVID-19) pneumonia who had barotrauma related to invasive mechanical ventilation at the authors' institution were observed. Purpose To determine if the rate of barotrauma in patients with COVID-19 infection was greater than in other patients requiring invasive mechanical ventilation at the authors' institution. Materials and Methods In this retrospective study, clinical and imaging data of patients seen between March 1, 2020, and April 6, 2020, who tested positive for COVID-19 and experienced barotrauma associated with invasive mechanical ventilation, were compared with patients without COVID-19 infection during the same period. Historical comparison was made to barotrauma rates of patients with acute respiratory distress syndrome from February 1, 2016, to February 1, 2020, at the authors' institution. Comparison of patient groups was performed using categoric or continuous statistical testing as appropriate, with multivariable regression analysis. Patient survival was assessed using Kaplan-Meier curves analysis. Results A total of 601 patients with COVID-19 infection underwent invasive mechanical ventilation (mean age, 63 years ± 15 [standard deviation]; 71% men). Of the total, there were 89 (15%) patients with one or more barotrauma events for a total of 145 barotrauma events (24% overall events) (95% confidence interval [CI]: 21%, 28%). During the same period, 196 patients without COVID-19 infection (mean age, 64 years ± 19; 52% men) with invasive mechanical ventilation had one barotrauma event (0.5%; 95% CI: 0%, 3%; P < .001 vs the group with COVID-19 infection). Of 285 patients with acute respiratory distress syndrome on invasive mechanical ventilation during the previous 4 years (mean age, 68 years ± 17; 60% men), 28 patients (10%) had 31 barotrauma events, with an overall barotrauma rate of 11% (95% CI: 8%, 15%; P < .001 vs the group with COVID-19 infection). Barotrauma is an independent risk factor for death in COVID-19 (odds ratio = 2.2; P = .03) and is associated with a longer hospital stay (odds ratio = 0.92; P < .001). Conclusion Patients with coronavirus disease 2019 (COVID-19) infection and invasive mechanical ventilation had a higher rate of barotrauma than patients with acute respiratory distress syndrome and patients without COVID-19 infection. © RSNA, 2020 Online supplemental material is available for this article.


Assuntos
Barotrauma/epidemiologia , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Pneumonia Viral/epidemiologia , Pneumonia Viral/terapia , Respiração Artificial/métodos , Respiração Artificial/estatística & dados numéricos , Idoso , COVID-19 , Causalidade , Comorbidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , New York/epidemiologia , Pandemias , Respiração Artificial/efeitos adversos , Estudos Retrospectivos , SARS-CoV-2
3.
J Hematop ; 17(1): 27-36, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38376724

RESUMO

Extranasal natural killer/T-cell lymphoma arising in the heart is rare and typically presents with non-specific clinical symptoms, necessitating a biopsy for a definitive diagnosis. We report an unusual case of a 48-year-old male who initially presented with chest pain and shortness of breath. Subsequent diagnosis via pericardial fluid analysis, including flow cytometry and immunohistochemical stains, revealed extranasal NK/T-cell lymphoma without sinonasal involvement. The analysis identified neoplastic lymphoid cells expressing CD2, cytoplasmic CD3, Epstein-Barr virus, and CD56 and exhibiting increased Ki-67 staining. Additionally, the patient developed hemophagocytosis lymphocytosis secondary to NK/T cell lymphoma. Treatment included an interleukin-1 receptor antagonist (anakinra), dexamethasone, rituximab, and etoposide. Unfortunately, the patient's condition rapidly deteriorated, leading to multiorgan failure and eventual demise. Given the rarity of this lymphoma, early diagnosis based on a high suspicion level provides the best chance for improved overall survival.


Assuntos
Infecções por Vírus Epstein-Barr , Linfo-Histiocitose Hemofagocítica , Linfoma Extranodal de Células T-NK , Linfoma de Células T Periférico , Derrame Pericárdico , Masculino , Humanos , Pessoa de Meia-Idade , Líquido Pericárdico , Linfo-Histiocitose Hemofagocítica/complicações , Herpesvirus Humano 4 , Derrame Pericárdico/diagnóstico , Linfoma Extranodal de Células T-NK/complicações , Proteína Antagonista do Receptor de Interleucina 1
4.
Acad Radiol ; 30(10): 2350-2357, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429779

RESUMO

Onboarding lays a foundation spanning multipart missions and teaches faculty how to engage and excel in the departmental environment. At the enterprise level, onboarding is a process to connect and support diverse teams, with a range of symbiotic phenotypes, into thriving departmental ecosystems. At the more personal level, onboarding involves guiding individuals with unique backgrounds, experiences, and strengths into their new roles, growing both the individual and the system. This guide will share elements of an initial step in the departmental faculty onboarding process, faculty orientation.


Assuntos
Ecossistema , Docentes , Humanos
5.
Acad Med ; 97(4): 497-502, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34495889

RESUMO

As the nation seeks to recruit and retain physician-scientists, gaps remain in understanding and addressing mitigatable challenges to the success of faculty from underrepresented minority (URM) backgrounds. The Doris Duke Charitable Foundation Fund to Retain Clinical Scientists program, implemented in 2015 at 10 academic medical centers in the United States, seeks to retain physician-scientists at risk of leaving science because of periods of extraordinary family caregiving needs, hardships that URM faculty-especially those who identify as female-are more likely to experience. At the annual Fund to Retain Clinical Scientists program directors conference in 2018, program directors-21% of whom identify as URM individuals and 13% as male-addressed issues that affect URM physician-scientists in particular. Key issues that threaten the retention of URM physician-scientists were identified through focused literature reviews; institutional environmental scans; and structured small- and large-group discussions with program directors, staff, and participants. These issues include bias and discrimination, personal wealth differential, the minority tax (i.e., service burdens placed on URM faculty who represent URM perspectives on committees and at conferences), lack of mentorship training, intersectionality and isolation, concerns about confirming stereotypes, and institutional-level factors. The authors present recommendations for how to create an environment in which URM physician-scientists can expect equitable opportunities to thrive, as institutions demonstrate proactive allyship and remove structural barriers to success. Recommendations include providing universal training to reduce interpersonal bias and discrimination, addressing the consequences of the personal wealth gap through financial counseling and benefits, measuring the service faculty members provide to the institution as advocates for URM faculty issues and compensating them appropriately, supporting URM faculty who wish to engage in national leadership programs, and sustaining institutional policies that address structural and interpersonal barriers to inclusive excellence.


Assuntos
Tutoria , Médicos , Docentes de Medicina , Feminino , Humanos , Masculino , Mentores , Grupos Minoritários/educação , Estados Unidos
6.
Acad Radiol ; 28(1): 112-118, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33268209

RESUMO

RATIONALE AND OBJECTIVES: The need for social distancing has resulted in rapid restructuring of medical student education in radiology. While students traditionally spend time learning in the reading room, remote clinical learning requires material shared without direct teaching at the radiology workstation. Can remote clinical learning meet or exceed the educational value of the traditional in-person learning experience? Can student engagement be matched or exceeded in a remote learning environment? MATERIALS AND METHODS: To replace the in-person reading room experience, a small-group learning session for medical students named Virtual Read-Out (VRO) was developed using teleconferencing software. After Institutional Review Board approval, two student groups were anonymously surveyed to assess differences in student engagement and perceived value between learning environments: "Conventional" students participating in the reading room (before the pandemic) and "Remote" students participating in VRO sessions. Students reported perceived frequency of a series of five-point Likert statements. Based on number of respondents, an independent t-test was performed to determine the significance of results between two groups. RESULTS: Twenty-seven conventional and 41 remote students responded. Remote students reported modest but significantly higher frequency of active participation in reviewing radiology exams (p < 0.05). There was significantly lower frequency of reported boredom among Remote students (p < 0.05). There was no significant difference in perceived educational value between the two groups. CONCLUSION: Students report a high degree of teaching quality, clinical relevance, and educational value regardless of remote or in-person learning format. Remote clinical radiology education can be achieved with equal or greater student interaction and perceived value in fewer contact hours than conventional learning in the reading room.


Assuntos
COVID-19 , Radiologia , Estudantes de Medicina , Humanos , Pandemias , SARS-CoV-2
7.
Radiol Cardiothorac Imaging ; 2(4): e200308, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33778610

RESUMO

PURPOSE: To evaluate pulmonary embolism (PE) prevalence at CT pulmonary angiography in patients testing positive for coronavirus disease 2019 (COVID-19) and factors associated with PE severity. MATERIALS AND METHODS: A retrospective, single-center study evaluated 62 patients who tested positive for COVID-19 who underwent CT pulmonary angiography between March 13 and April 5, 2020. Another 62-patient cohort who underwent CT pulmonary angiography before the first reported local COVID-19 case was retrospectively selected. The relative rate of CT pulmonary angiography positivity was recorded. For the COVID-19 positive cohort, comorbidities, laboratory values, clinical outcome, and venous thrombosis of the patients were recorded. Two thoracic radiologists assessed embolic severity using the Mastora system and evaluated right heart strain. Factors associated with PE and arterial obstruction severity were evaluated by using statistical analysis. A P value < .05 was considered significant. RESULTS: Of the patients testing positive for COVID-19, 37.1% had PE, higher than 14.5% of pre-COVID-19 patients (P = .007). d-dimer levels closest to CT pulmonary angiography date correlated with the Mastora obstruction score. Receiver operating characteristic analysis identified optimal sensitivity (95%) and specificity (71%) for PE diagnosis at 1394 ng/mL d-dimer units. The mean d-dimer level was 1774 ng/mL and 6432 ng/mL d-dimer units in CT pulmonary angiography-negative and CT pulmonary angiography-positive subgroups, respectively (P < .001). One additional patient with negative results at CT pulmonary angiography had deep venous thrombosis, thus resulting in 38.7% with PE or deep venous thrombosis, despite 40% receiving prophylactic anticoagulation. Other factors did not demonstrate significant PE association. CONCLUSION: A total of 37.1% of COVID-19 patients underwent CT pulmonary angiographic examinations diagnosing PE. PE can be a cause of decompensation in patients testing positive for COVID-19, and d-dimer can be used to stratify patients in terms of PE risk and severity.Supplemental material is available for this article.© RSNA, 2020.

8.
N Engl J Med ; 347(11): 806-15, 2002 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-12226151

RESUMO

BACKGROUND: Workers from the Fire Department of New York City were exposed to a variety of inhaled materials during and after the collapse of the World Trade Center. We evaluated clinical features in a series of 332 firefighters in whom severe cough developed after exposure and the prevalence and severity of bronchial hyperreactivity in firefighters without severe cough classified according to the level of exposure. METHODS: "World Trade Center cough" was defined as a persistent cough that developed after exposure to the site and was accompanied by respiratory symptoms severe enough to require medical leave for at least four weeks. Evaluation of exposed firefighters included completion of a standard questionnaire, spirometry, airway-responsiveness testing, and chest imaging. RESULTS: In the first six months after September 11, 2001, World Trade Center cough occurred in 128 of 1636 firefighters with a high level of exposure (8 percent), 187 of 6958 with a moderate level of exposure (3 percent), and 17 of 1320 with a low level of exposure (1 percent). In addition, 95 percent had symptoms of dyspnea, 87 percent had gastroesophageal reflux disease, and 54 percent had nasal congestion. Of those tested before treatment of World Trade Center cough, 63 percent of firefighters (149 of 237) had a response to a bronchodilator and 24 percent (9 of 37) had bronchial hyperreactivity. Chest radiographs were unchanged from precollapse findings in 319 of the 332 with World Trade Center cough. Among the cohort without severe cough, bronchial hyperreactivity was present in 77 firefighters with a high level of exposure (23 percent) and 26 with a moderate level of exposure (8 percent). CONCLUSIONS: Intense, short-term exposure to materials generated during the collapse of the World Trade Center was associated with bronchial responsiveness and the development of cough. Clinical and physiological severity was related to the intensity of exposure.


Assuntos
Hiper-Reatividade Brônquica/epidemiologia , Tosse/epidemiologia , Doenças Profissionais/epidemiologia , Trabalho de Resgate , Adulto , Hiper-Reatividade Brônquica/classificação , Hiper-Reatividade Brônquica/etiologia , Tosse/classificação , Tosse/etiologia , Pessoas com Deficiência/estatística & dados numéricos , Refluxo Gastroesofágico/epidemiologia , Humanos , Modelos Logísticos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , Doenças Profissionais/classificação , Doenças Profissionais/etiologia , Mecânica Respiratória , Dispositivos de Proteção Respiratória/estatística & dados numéricos , Espirometria , Terrorismo , Tomografia Computadorizada por Raios X
9.
Acad Radiol ; 22(7): 933-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25843902

RESUMO

RATIONALE AND OBJECTIVES: The newly formed Alliance of Directors and Vice Chairs of Education in Radiology (ADVICER), a group within the Alliance for Clinician Educators in Radiology, identified an acute need for a generic job description template for Vice Chairs of Education in Radiology, a role that is being developed in many academic Departments of Radiology. Eighty-three percent of current members who responded to a survey had no detailed job description, and over half had no job description at all. Having a comprehensive and detailed job description is vital to developing this key position. MATERIALS AND METHODS: Using the results of a survey sent to ADVICER members and seven Education Vice Chair job descriptions provided by members, the authors developed a detailed job description encompassing all potential elements of this position. RESULTS: Only 17% of survey respondents had a detailed job description. The role of an Education Vice Chair varies significantly between institutions in its scope and level of responsibilities. The resultant generic job description that was devised is intended to provide a template that would be modified by the candidate or the Department Chair. It is unlikely that any one individual would perform all the described activities. CONCLUSIONS: ADVICER has developed a comprehensive, flexible job description for Vice Chair of Education in Radiology that can be adapted by institutions as appropriate. It can be downloaded from http://aur.org/ADVICER/.


Assuntos
Centros Médicos Acadêmicos , Descrição de Cargo , Admissão e Escalonamento de Pessoal/organização & administração , Radiologia/educação , Redação , Algoritmos , Radiologia/organização & administração , Estados Unidos , Recursos Humanos
10.
Radiol Clin North Am ; 40(1): 1-19, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11813813

RESUMO

High-resolution CT is accepted as an accurate noninvasive means of diagnosing bronchiectasis. A wide spectrum of abnormalities may be identified at HRCT in patients with airway disease, including various distinctive patterns of bronchiectasis in specific clinical settings, such as ABPA, MAC infection, AIDS, and CF. Characteristic CT findings occasionally suggest a specific diagnosis that may not have been under clinical consideration. HRCT also provides significant clinical use in assessing the degree and extent of airway disease, and allows noninvasive monitoring of disease progression, regression, or response to therapy.


Assuntos
Broncopatias/diagnóstico por imagem , Bronquiectasia/diagnóstico por imagem , Pneumopatias/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico por imagem , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Idoso , Aspergilose Broncopulmonar Alérgica/diagnóstico por imagem , Bronquiectasia/complicações , Bronquiectasia/etiologia , Bronquiolite/diagnóstico por imagem , Bronquiolite Obliterante/diagnóstico por imagem , Bronquite/diagnóstico por imagem , Broncografia , Carcinoma de Células Escamosas/diagnóstico por imagem , Fibrose Cística/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/complicações , Pneumonia por Pneumocystis/diagnóstico por imagem , Radiografia Torácica , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos
11.
Clin Imaging ; 28(5): 317-21, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15471661

RESUMO

PURPOSE: The purpose of this study was to characterize the diagnostic performance of a regimen of CT screening for lung cancer. METHODS: Using a common protocol/regimen of screening, 2968 asymptomatic persons at high risk for lung cancer were enrolled in two studies [Early Lung Cancer Action Projects (ELCAP) I and II] for baseline and annual repeat screening. A total of 4538 annual repeat screenings were performed. The regimen's diagnostic performance was characterized in terms of frequency of positive result of the initial CT as well as of screen-diagnosis and Stage I screen-diagnosis among all diagnoses (interim-diagnoses included), all separately for baseline and annual repeat screenings. RESULTS: The proportions with positive result of the initial CT were 12% and 6% in the baseline and repeat screenings, respectively. The proportions of screen-diagnoses among all diagnoses (interim-diagnoses included) were 97% and 99% in the baseline and repeat cycles, respectively. The corresponding proportions of pre-surgical Stage I screen-diagnoses were 95% and 93%. CONCLUSION: The performance of the ELCAP regimen is quite satisfactory in avoiding over many positive results of the initial CT, and it produces highly promising diagnostic results as for the attainment of cure by early intervention.


Assuntos
Neoplasias Pulmonares/diagnóstico , Programas de Rastreamento/métodos , Fumar/efeitos adversos , Nódulo Pulmonar Solitário/patologia , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Incidência , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Sensibilidade e Especificidade , Fumar/epidemiologia , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/epidemiologia
12.
Clin Nucl Med ; 27(4): 275-82, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11914668

RESUMO

PURPOSE: The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management. METHODS: F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated. RESULTS: All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm +/- 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%. CONCLUSIONS: Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Fluordesoxiglucose F18 , Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
PLoS One ; 7(7): e39403, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22768300

RESUMO

BACKGROUND: Low-dose computed tomography (CT) for lung cancer screening can reduce lung cancer mortality. The National Lung Screening Trial reported a 20% reduction in lung cancer mortality in high-risk smokers. However, CT scanning is extremely sensitive and detects non-calcified nodules (NCNs) in 24-50% of subjects, suggesting an unacceptably high false-positive rate. We hypothesized that by reviewing demographic, clinical and nodule characteristics, we could identify risk factors associated with the presence of nodules on screening CT, and with the probability that a NCN was malignant. METHODS: We performed a longitudinal lung cancer biomarker discovery trial (NYU LCBC) that included low-dose CT-screening of high-risk individuals over 50 years of age, with more than 20 pack-year smoking histories, living in an urban setting, and with a potential for asbestos exposure. We used case-control studies to identify risk factors associated with the presence of nodules (n=625) versus no nodules (n=557), and lung cancer patients (n=30) versus benign nodules (n=128). RESULTS: The NYU LCBC followed 1182 study subjects prospectively over a 10-year period. We found 52% to have NCNs >4 mm on their baseline screen. Most of the nodules were stable, and 9.7% of solid and 26.2% of sub-solid nodules resolved. We diagnosed 30 lung cancers, 26 stage I. Three patients had synchronous primary lung cancers or multifocal disease. Thus, there were 33 lung cancers: 10 incident, and 23 prevalent. A sub-group of the prevalent group were stable for a prolonged period prior to diagnosis. These were all stage I at diagnosis and 12/13 were adenocarcinomas. CONCLUSIONS: NCNs are common among CT-screened high-risk subjects and can often be managed conservatively. Risk factors for malignancy included increasing age, size and number of nodules, reduced FEV1 and FVC, and increased pack-years smoking. A sub-group of screen-detected cancers are slow-growing and may contribute to over-diagnosis and lead-time biases.


Assuntos
Adenocarcinoma Bronquioloalveolar/diagnóstico por imagem , Adenocarcinoma Bronquioloalveolar/mortalidade , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/mortalidade , Tomografia Computadorizada por Raios X , População Urbana , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/efeitos adversos , Fatores de Tempo
18.
Magn Reson Med ; 56(4): 733-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16958076

RESUMO

Diseases of the small airspaces represent an increasingly important health problem. Asthma is primarily a disease of airway dysfunction, while chronic obstructive pulmonary disease (COPD) is associated with abnormalities in both the small airways and the alveoli. Conventional diffusion magnetic resonance imaging (MRI) of hyperpolarized noble gases, because of the short T(2)* of the gas, is only capable of monitoring diffusion over short times and hence only short distances. Diffusion imaging is therefore only sensitive to changes in small structures of the lung (primarily the alveoli), and will not adequately interrogate diffusion along the longitudinal axes of bronchi and bronchioles. In this communication we present a new method, termed diffusional kurtosis imaging (DKI), that is particularly sensitive to diffusion over longer distances. DKI may therefore be more sensitive to abnormalities in the bronchioles and bronchi than conventional diffusion imaging. Preliminary DKI measurements on healthy human subjects and one patient with symptoms suggestive of small airway disease are presented. Although the apparent diffusion coefficient (ADC) in the patient was similar to that in the normal controls, diffusional kurtosis was markedly reduced. This suggests that DKI measurements may be useful for assessing diseases of the small airways.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Hélio , Pneumopatias Obstrutivas/fisiopatologia , Pulmão/fisiologia , Ventilação Pulmonar , Artefatos , Humanos , Isótopos , Pulmão/anatomia & histologia , Sensibilidade e Especificidade
19.
Magn Reson Med ; 55(5): 1132-41, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16586457

RESUMO

Hyperpolarized helium (3He) gas MRI has the potential to assess pulmonary function. The non-equilibrium state of hyperpolarized 3He results in the continual depletion of the signal level over the course of excitations. Under non-equilibrium conditions the relationship between the signal-to-noise ratio (SNR) and the number of excitations significantly deviates from that established in the equilibrium state. In many circumstances the SNR increases or remains the same when the number of data acquisitions decreases. This provides a unique opportunity for performing parallel MRI in such a way that both the temporal and spatial resolution will increase without the conventional decrease in the SNR. In this study an analytical relationship between the SNR and the number of excitations for any flip angle was developed. Second, the point-spread function (PSF) was utilized to quantitatively demonstrate the unconventional SNR behavior for parallel imaging in hyperpolarized gas MRI. Third, a 24-channel (24ch) receive and two-channel (2ch) transmit phased-array system was developed to experimentally prove the theoretical predictions with 3He MRI. The in vivo experimental results prove that significant temporal resolution can be gained without the usual SNR loss in an equilibrium system, and that the entire lung can be scanned within one breath-hold (approximately 13 s) by applying parallel imaging to 3D data acquisition.


Assuntos
Hélio , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Armazenamento e Recuperação da Informação/métodos , Pulmão/anatomia & histologia , Imageamento por Ressonância Magnética/instrumentação , Administração por Inalação , Algoritmos , Metodologias Computacionais , Desenho de Equipamento , Análise de Falha de Equipamento , Hélio/administração & dosagem , Humanos , Aumento da Imagem/instrumentação , Interpretação de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Imageamento por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 4278-81, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281180

RESUMO

Hyperpolarized 3He gas MRI has a serious potential for assessing pulmonary functions. Due to the fact that the non-equilibrium of the gas results in a steady depletion of the signal level over the course of the excitations, the signal-tonoise ratio (SNR) can be independent of the number of the data acquisitions under certain circumstances. This provides a unique opportunity for parallel MRI for gaining both temporal and spatial resolution without reducing SNR. We have built a 24-channel receive / 2-channel transmit phased array system for 3He parallel imaging. Our in vivo experimental results proved that the significant temporal and spatial resolution can be gained at no cost to the SNR. With 3D data acquisition, eight fold (2x4) scan time reduction can be achieved without any aliasing in images. Additionally, a rigid analysis using the low impedance preamplifier for decoupling presented evidence of strong coupling.

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