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1.
J Magn Reson Imaging ; 52(2): 499-509, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31950573

RESUMO

BACKGROUND: The poor prognosis of cardiac sarcoidosis (CS) underscores the need for risk stratification. PURPOSE: To investigate the prognostic significance of ventricular/myocardial remodeling features in sarcoidosis. STUDY TYPE: Retrospective. POPULATION: In all, 132 biopsy-proven sarcoidosis patients imaged from 2008 to 2018. The primary endpoint was a composite of cardiac mortality, new onset arrhythmias, hospitalization for heart failure, and device implantation. FIELD STRENGTH/SEQUENCE: No field strength or sequence restrictions. ASSESSMENT: Global and regional ventricular/myocardial remodeling features were assessed by standard volumetric measurements and automated function imaging postprocessing analysis. STATISTICAL TESTS: Student's t-test or Mann-Whitney test (chi2 test or Fisher's exact test for categorical variables) were used for comparisons. Cox-proportional hazards regression model, univariate /multivariate analyses, and receiver operating characteristic were performed to relate clinical/lab data, imaging parameters to the endpoints. RESULTS: Over a median follow-up of 40.7 (interquartile range 18.8-60.5) months, 41 (31.1%) patients developed adverse cardiac events. Abnormal left ventricular (LV) geometric remodeling alterations (measured by LV mass index and relative wall thickness) occurred 3.66-fold more frequently in patients with endpoints than patients without. The ratio of patients with endpoints increased as ventricular remodeling phenotype progressed. In patients with endpoints, regional myocardial wall thickness (RMWT) was significantly (P = 0.022) increased in six clustered LV segments located in the middle interventricular septum and basal/middle anterolateral walls. In all of the abnormal ventricular remodeling stages, patients with endpoints constantly had higher mean RMWT than those without. Among clinical, electrocardiographic, and imaging parameters, LV mass index (hazard ratio [HR] 1.010 95% confidence interval [CI] 1.002-1.018, P = 0.017) and mean RMWT (HR 3.482 95% CI 1.679-7.223, P = 0.001) were independently associated with endpoints. Sarcoidosis patients without this RMWT distribution pattern were significantly (P < 0.001) more likely to be free of the occurrence of subsequent cardiac events. DATA CONCLUSION: Regional myocardial remodeling characteristics are associated with subsequent adverse cardiac events in sarcoidosis. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2 J. Magn. Reson. Imaging 2020;52:499-509.


Assuntos
Sarcoidose , Função Ventricular Esquerda , Humanos , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Sarcoidose/diagnóstico por imagem , Remodelação Ventricular
2.
Neuroophthalmology ; 43(3): 185-191, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31312243

RESUMO

Castleman disease (CD) is a rare lymphoproliferative disorder that may present with various autoimmune, inflammatory, or neurologic syndromes. This is a case of a 21-year-old woman who presented with signs and symptoms of pseudotumour cerebri (PTC) who subsequently developed myasthenia gravis (MG), and was incidentally found to have a large mass in the posterior mediastinum. Upon resection, the mass was classified as unicentric CD involved with follicular dendritic cell sarcoma. Following treatment with IVIG in the setting of progressive weakness and dyspnea, she has had complete symptom resolution while maintained on a low dose of pyridostigmine for the last two years. There are 13 cases of MG and five cases of optic disc edema described as PTC associated with CD in the literature, but to our knowledge, this is the sole case reported of the intersection of all three conditions in one patient. Increased serum levels of interleukin-6 and vascular endothelial growth factor may provide clues as to the association of CD with these neurologic syndromes.

3.
Cureus ; 15(5): e39031, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37323365

RESUMO

Illicit drugs, especially those injected intravenously, are becoming increasingly more common worldwide. Individuals who use intravenous drugs often reuse or share needles which predisposes them to life-threatening infections. We present the case of a patient who was injecting intravenous drugs into her internal jugular vein, which eventually led to acutely worsening sepsis secondary to fungal infective endocarditis and bilateral septic pulmonary emboli. Transthoracic echocardiogram demonstrated multilobulated and spherical vegetations on the tricuspid and mitral valves, respectively. On computed tomography of the thorax, numerous cavitary lesions and ground-glass opacities were present in both lungs. Multiple hyperdense, linear structures consistent with broken needles were seen on chest radiography. It is important for radiologists to recognize the possibility of broken needles in patients with a history of intravenous drug use as astute recognition of broken needles may lead to better source control and improved outcomes.

4.
Pediatr Radiol ; 42(5): 527-35, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22430480

RESUMO

BACKGROUND: Patient organ doses may be estimated from CTDI values. More accurate estimates may be obtained by measuring KERMA (Kinetic Energy Released in Matter) in anthropomorphic phantoms and referencing these values to free-in-air X-ray intensity. OBJECTIVE: To measure KERMA ratios (R(K)) in pediatric phantoms at CT. MATERIALS & METHODS: CT scans produce an air KERMA K in a phantom and an air KERMA K(CT) at isocenter. KERMA ratios (R(K)) are defined as (K/K(CT)), measured using TLD chips in phantoms representing newborns to 10-year-olds. RESULTS: R(K) in the newborn is approximately constant. For the other phantoms, there is a peak R(K) value in the neck. The median R(K) values for the GE scanner at 120 kV were 0.92, 0.83, 0.77 and 0.76 for newborns, 1-year-olds, 5-year-olds and 10-year-olds, respectively. Organ R(K) values were 0.91 ± 0.04, 0.84 ± 0.07, 0.74 ± 0.09 and 0.72 ± 0.10 in newborns, 1-year-olds, 5-year-olds and 10-year-olds, respectively. At 120 kV, a Siemens Sensation 16 scanner had R(K) values 5% higher than those of the GE LightSpeed Ultra. CONCLUSION: KERMA ratios may be combined with air KERMA measurements at the isocenter to estimate organ doses in pediatric CT patients.


Assuntos
Imagens de Fantasmas , Doses de Radiação , Radiometria/métodos , Tomografia Computadorizada por Raios X , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
5.
Int J Cardiovasc Imaging ; 38(8): 1825-1836, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35194707

RESUMO

Recognizing early cardiac sarcoidosis (CS) imaging phenotypes can help identify opportunities for effective treatment before irreversible myocardial pathology occurs. We aimed to characterize regional CS myocardial remodeling features correlating with future adverse cardiac events by coupling automated image processing and data analysis on cardiac magnetic resonance (CMR) imaging datasets. A deep convolutional neural network (DCNN) was used to process a CMR database of a 10-year cohort of 117 consecutive biopsy-proven sarcoidosis patients. The maximum relevance - minimum redundancy method was used to select the best subset of all the features-24 (from manual processing) and 232 (from automated processing) left ventricular (LV) structural/functional features. Three machine learning (ML) algorithms, logistic regression (LogR), support vector machine (SVM) and multi-layer neural networks (MLP), were used to build classifiers to categorize endpoints. Over a median follow-up of 41.8 (inter-quartile range 20.4-60.5) months, 35 sarcoidosis patients experienced a total of 43 cardiac events. After manual processing, LV ejection fraction (LVEF), late gadolinium enhancement, abnormal segmental wall motion, LV mass (LVM), LVMI index (LVMI), septal wall thickness, lateral wall thickness, relative wall thickness, and wall thickness of 9 (out of 17) individual LV segments were significantly different between patients with and without endpoints. After automated processing, LVEF, end-diastolic volume, end-systolic volume, LV mass and wall thickness of 92 (out of 216) individual LV segments were significantly different between patients with and without endpoints. To achieve the best predictive performance, ML algorithms selected lateral wall thickness, abnormal segmental wall motion, septal wall thickness, and increased wall thickness of 3 individual segments after manual image processing, and selected end-diastolic volume and 7 individual segments after automated image processing. LogR, SVM and MLP based on automated image processing consistently showed better predictive accuracies than those based on manual image processing. Automated image processing with a DCNN improves data resolution and regional CS myocardial remodeling pattern recognition, suggesting that a framework coupling automated image processing with data analysis can help clinical risk stratification.


Assuntos
Doenças Cardiovasculares , Aprendizado Profundo , Sarcoidose , Humanos , Meios de Contraste , Imagem Cinética por Ressonância Magnética/métodos , Valor Preditivo dos Testes , Gadolínio , Função Ventricular Esquerda , Volume Sistólico , Sarcoidose/diagnóstico por imagem
6.
Med Phys ; 38(10): 5362-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21992356

RESUMO

PURPOSE: To estimate in-patient KERMA for specific organs in computed tomography (CT) scanning using ratios to isocenter free-in-air KERMA obtained using a Rando phantom. METHOD: A CT scan of an anthropomorphic phantom results in an air KERMA K at a selected phantom location and air kerma K(CT) at the CT scanner isocenter when the scan is repeated in the absence of the phantom. The authors define the KERMA ratio (R(K)) as K∕ K(CT), which were experimentally determined in a Male Rando Phantom using lithium fluoride chips (TLD-100). R(K) values were obtained for a total of 400 individual point locations, as well as for 25 individual organs of interest in CT dosimetry. CT examinations of Rando were performed on a GE LightSpeed Ultra scanner operated at 80 kV, 120 kV, and 140 kV, as well as a Siemens Sensation 16 operated at 120 kV. RESULTS: At 120 kV, median R(K) values for the GE and Siemens scanners were 0.60 and 0.64, respectively. The 10th percentile R(K) values ranged from 0.34 at 80 kV to 0.54 at 140 kV, and the 90th percentile R(K) values ranged from 0.64 at 80 kV to 0.78 at 140 kV. The average R(K) for the 25 Rando organs at 120 kV was 0.61 ± 0.08. Average R(K) values in the head, chest, and abdomen showed little variation. Relative to R(K) values in the head, chest, and abdomen obtained at 120 kV, R(K) values were about 12% lower in the pelvis and about 58% higher in the cervical spine region. Average R(K) values were about 6% higher on the Siemens Sensation 16 scanner than the GE LightSpeed Ultra. Reducing the x-ray tube voltage from 120 kV to 80 kV resulted in an average reduction in R(K) value of 34%, whereas increasing the x-ray tube voltage to 140 kV increased the average R(K) value by 9%. CONCLUSIONS: In-patient to isocenter relative KERMA values in Rando phantom can be used to estimate organ doses in similar sized adults undergoing CT examinations from easily measured air KERMA values at the isocenter (free in air). Conversion from in-patient air KERMA values to tissue dose would require the use of energy-appropriate conversion factors.


Assuntos
Dosimetria Termoluminescente/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Ar , Algoritmos , Tamanho Corporal , Humanos , Masculino , Método de Monte Carlo , Imagens de Fantasmas , Radiometria , Distribuição Tecidual , Tomógrafos Computadorizados , Água/química , Imagem Corporal Total/métodos , Raios X
7.
Radiol Case Rep ; 16(8): 2158-2163, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34158908

RESUMO

Mucoepidermoid carcinoma of the thymus is a rare primary thymic carcinoma. Radiologic imaging of this malignancy is rarely reported in literature. We present a patient who complained of a chronic cough for two years who was later found to have mucoepidermoid carcinoma of the thymus. Chest radiograph revealed a large anterior mediastinal mass. Follow-up computed tomography of the thorax demonstrated a large, heterogeneous anterior mediastinal mass with traversing vessels. F-18 fluorodeoxyglucose positron emission tomography-computed tomography demonstrated high avidity in the lesion with areas of diminished activity thought to represent necrosis. Following surgical resection, pathology revealed high-grade mucoepidermoid carcinoma of the thymus extending into the skeletal muscle and pericardium with evidence of lymphovascular invasion. The patient received external beam radiation therapy and has remained disease-free for three years.

8.
Radiol Case Rep ; 16(11): 3250-3254, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34484526

RESUMO

Tracheal and bronchial diverticula are outpouchings arising from the trachea or bronchus. We present a case of a 35-year-old female who presented to the emergency department following a motor vehicle accident and was found to have multiple round, air-filled structures within the mediastinum on computed tomography of the thorax, concerning for pneumomediastinum. The patient had a negative fluoroscopic esophagography and subsequent imaging indicated tracheal and bronchial diverticula. While they are often asymptomatic and incidentally found, tracheal and bronchial diverticula may be misdiagnosed as pneumomediastinum, especially in the setting of blunt or penetrating trauma to the thorax.

9.
Thorax ; 65(9): 833-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20805183

RESUMO

A pathological diagnosis of pulmonary Langerhans cell histiocytosis (PLCH) usually requires a surgical lung biopsy. To date, diagnosis of PLCH by core needle biopsy has not been reported. Three cases are presented of PLCH diagnosed by CT-guided core biopsy in adult female smokers found to have multiple small bilateral lung nodules. The nodules biopsied were 5 mm, 7 mm and 1 cm in size, and showed interstitial expansion by Langerhans cells and eosinophils. CT-guided core biopsy should be considered as one of the less invasive techniques by which a pathological diagnosis of PLCH can be established.


Assuntos
Biópsia por Agulha/métodos , Histiocitose de Células de Langerhans/patologia , Pneumopatias/patologia , Idoso , Feminino , Histiocitose de Células de Langerhans/diagnóstico por imagem , Humanos , Pneumopatias/diagnóstico por imagem , Pessoa de Meia-Idade , Radiografia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos
10.
Lancet Oncol ; 10(9): 885-94, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19717090

RESUMO

Advances in technology have changed the treatment of patients with early stage non-small-cell lung cancer who are not healthy enough for standard surgical resection. Previously, patients with severe underlying cardiopulmonary dysfunction were often dissuaded from pursuing definitive therapy, even though most patients died from their lung cancer and not as a result of comorbid medical illness. Recent advances in the technology to treat early stage disease have led to new-found enthusiasm for treating and studying high-risk patients. This Review focuses on the management of these patients, including use of conformal radiotherapy, stereotactic body radiation therapy, sublobar resection, intraoperative brachytherapy, and radiofrequency ablation. Ongoing challenges are presented and prospective data are emphasised.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Braquiterapia/métodos , Carcinoma Pulmonar de Células não Pequenas/patologia , Ablação por Cateter/métodos , Fracionamento da Dose de Radiação , Humanos , Neoplasias Pulmonares/patologia , Radiocirurgia/métodos , Radioterapia Conformacional/métodos
11.
Int J Cardiol ; 276: 1-7, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30413307

RESUMO

BACKGROUND: In patients with acute anterior myocardial infarction (MI), sometimes an "apical ballooning" contractile dysfunction pattern that exceeds factual myocardial injury is identified in the ventriculography and bedside echocardiography. The hemodynamic consequences/sequela of this "Tako-tsobu effect" has not been well delineated. Of note, this anatomic imaging finding often misleads frontline physicians who assume reciprocal causation of persistent cardiac pump failure and ventricular pressure overload. METHODS AND RESULTS: Using real-time myocardial perfusion contrast echocardiography (MCE), we investigated myocardial (microvascular) perfusion in 60 patients after acute MI and coronary revascularization. Twenty-eight percent of the studied patients showed significantly mismatched myocardial perfusion and contractile defects. In these patients, an integrated imaging assessment with coronary angiography/ventriculography, deformation echocardiography, and MCE proved that the myocardial mechanic abnormalities significantly exceeded the defected perfusion areas. Compared with 72% of the patients without perfusion-contractility mismatch, apparently worse systolic functions (left ventricular ejection, wall motion score, and systolic longitudinal strain) in these patients did not change diastolic ventricular filling pressures (E/E' and E/A) or hemodynamic consequences/adverse events. Both systolic and diastolic functions in patients with perfusion-contractility mismatch appeared to be comparable with those in patients with Tako-tsubo syndrome. CONCLUSIONS: Real-time MCE identifies discrepant myocardial microvascular perfusion and mechanics in patients with acute MI. The "Tako-tsubo effect" in patients with perfusion-contractility mismatch does not cause diastolic filling pressure change or worse hemodynamic consequence/cardiac event.


Assuntos
Ecocardiografia Doppler/métodos , Microcirculação , Infarto do Miocárdio/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Cardiomiopatia de Takotsubo/diagnóstico por imagem , Idoso , Feminino , Seguimentos , Humanos , Masculino , Microcirculação/fisiologia , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Projetos Piloto , Cardiomiopatia de Takotsubo/fisiopatologia
13.
J Thorac Dis ; 10(5): 3027-3038, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29997970

RESUMO

BACKGROUND: Although morphological abnormalities of the heart appear to be remarkable, most patients with tako-tsubo cardiomyopathy (TTC) remain clinically stable. We investigate real time changes in the left ventricular (LV) and right ventricular (RV) mechanics and function to explore the mechanism to preserve hemodynamics. METHODS: With deformation and Doppler echocardiography, we evaluated myocardial mechanics and ventricular function/hemodynamics simultaneously in 103 consecutive TTC patients admitted from 01/01/2008 through 12/31/2015. The coronary angiography and left ventriculography were performed to rule out culprit coronary artery stenosis (CAS). We included 66 patients in a control group with matched age, sex, and risk factors for coronary artery disease (CAD), and 41 patients in a group of myocardial infarction induced cardiogenic shock, who required circulatory supporting devices to maintain hemodynamic stability. RESULTS: Although systolic myocardial strain in most of the LV segments was significantly impaired, 4 basal LV segments remained functionally active during acute stage of TTC. The impairment in the myocardial strain of the RV apex could extend to the middle segments, but basal RV systolic strain was also preserved. Despites comparable apical to basal strain gradients, LV and RV displayed discrepant functional/hemodynamic status. In contrast to LV, RV functional/hemodynamic parameters appeared to be hyper-dynamic. This unique RV strain pattern remained unchanged in patients with atypical (mid-LV cavity) TTC. In 41 patients with myocardial infarction induced cardiogenic shock, RV exhibited comparable mechanic and functional features with those in TTC patients. CONCLUSIONS: The identified LV and RV mechanic changes appear to support interventricular hemodynamic dependence during TTC, which may represent a universal rescue mechanism in a jeopardized or injured heart.

14.
Int J Cardiovasc Imaging ; 34(2): 251-262, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28889326

RESUMO

The poor prognosis of cardiac sarcoidosis (CS) underscores the need for risk stratification. We evaluated 84 consecutive sarcoidosis patients who were referred for echocardiographic studies for cardiac symptoms or abnormal electrocardiograms. In 54 patients without previous diagnosis of CS or other known structural heart disease, 13 reached endpoints during (median) 24 months follow up. Significantly impaired peak systolic longitudinal strain in their original echocardiograms were identified in 13 of 17 left ventricular segments, clustering in the free wall, interventricular septum and apex. The regional (including 13 clustered segments) peak systolic longitudinal strain (RPSLS) were significantly impaired in patients with endpoints, compared with those without [(-11.4 ± 4.45) vs. (-18.7 ± 3.76) %, P < 0.00001]. Cox multivariate regression analysis revealed that RPSLS was independently associated with endpoints (HR 1.24; 95% CI 1.08-1.42, P = 0.002). Receiver operating characteristic curve suggested a cut-off RPSLS value of -15.0% (84.6% sensitivity and 86.8% specificity) to predict the occurrence of endpoints. Impaired RPSLS correlates with risk of adverse cardiac events in patients with extra-cardiac sarcoidosis.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Ecocardiografia , Contração Miocárdica , Sarcoidose/diagnóstico por imagem , Função Ventricular Esquerda , Adulto , Área Sob a Curva , Fenômenos Biomecânicos , Cardiomiopatias/fisiopatologia , Distribuição de Qui-Quadrado , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Sarcoidose/fisiopatologia , Fatores de Tempo
15.
J Thorac Cardiovasc Surg ; 153(6): 1592-1597, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28274562

RESUMO

OBJECTIVE: Cancer and Leukemia Group B 140503 is an ongoing, multicenter randomized trial assessing whether sublobar resection is equivalent to lobectomy for the treatment of stage I A non-small cell lung cancer (NSCLC) ≤2 cm in diameter. The objective of this report is to determine the reasons precluding intraoperative randomization. METHODS: From June 15, 2007, to March 22, 2013, 637 patients were preregistered to the trial. Three hundred eighty-nine were randomized successfully (61%), and 248 patients were not randomized (39%). We analyzed the reasons for nonrandomization among a subset of the nonrandomized patients (208) for whom additional data were available. RESULTS: Of these 208 patients, undiagnosed benign nodules (n =104, 16% of all registered patients) and understaging of NSCLC (n =45, 7% of all registered patients) were the dominant reasons precluding randomization. Granulomas represent one-quarter of the benign nodules. The understaged patients had unsuspected nodal metastases (n =28) or other more advanced NSCLC. The rate of randomization was significantly greater in those patients who had a preoperative biopsy (P <.001). CONCLUSIONS: In a carefully monitored cohort of patients with suspected small NSCLC ≤2 cm, a substantial number are misdiagnosed (benign nodules) or understaged. These patients may not have benefited from a thoracic surgical procedure. Preoperative biopsy significantly increased the rate of correct diagnosis. Preoperative biopsy of small suspected NSCLC will reduce the number of nontherapeutic or unnecessary thoracic procedures. Accuracy in preoperative diagnosis is increasingly important as more such small nodules are discovered through lung cancer screening.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Seleção de Pacientes , Idoso , Biópsia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Erros de Diagnóstico , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pneumonectomia/efeitos adversos , Pneumonectomia/métodos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Resultado do Tratamento , Carga Tumoral , Procedimentos Desnecessários
16.
Acad Radiol ; 13(11): 1355-66, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17070453

RESUMO

RATIONALE AND OBJECTIVES: We investigated the effect of random noise and lesion size on detection performance in mammography. MATERIALS AND METHODS: Digital mammograms were obtained of an anthropomorphic breast phantom with and without simulated mass lesions. Digital versions of the mass lesions, ranging in size from 0.8 to 12 mm, were added back to the breast phantom image. Four alternate forced choice experiments were performed to determine the lesion contrast required to achieve a 92% correct lesion detection rate, denoted I92. Experiments were performed using identical phantom images and different versions of phantom images obtained using the same techniques but with different random noise patterns. RESULTS: For lesions larger than 1 mm, the slope of the contrast detail curves was always positive. This behavior contrasts with conventional contrast-detail curves in uniform backgrounds in which the slope is approximately -0.5. There was no difference between twinned experiments and those obtained using different patterns of random noise for lesions greater than 1 mm. When the lesion size was reduced below 1 mm, the detection threshold increased indicating a deterioration of lesion detectability, and detection performance was significantly lower when random noise patterns were used. CONCLUSION: Our results suggest that lesion detection is dominated by anatomical structure for lesions with a size >1 mm, but by random noise for submillimeter sized lesions.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Mamografia , Intensificação de Imagem Radiográfica , Inteligência Artificial , Neoplasias da Mama/epidemiologia , Apresentação de Dados , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Variações Dependentes do Observador , Imagens de Fantasmas , Análise e Desempenho de Tarefas , Interface Usuário-Computador
17.
Chest ; 127(3): 909-15, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15764775

RESUMO

STUDY OBJECTIVE: To demonstrate the efficacy, safety, and appropriate mode of instillation of talc for sclerosis in treatment of malignant pleural effusions (MPEs). DESIGN: A prospective, randomized trial was designed to compare thoracoscopy with talc insufflation (TTI) to thoracostomy and talc slurry (TS) for patients with documented MPE. MEASUREMENTS: The primary end point was 30-day freedom from radiographic MPE recurrence among surviving patients whose lungs initially re-expanded > 90%. Morbidity, mortality, and quality of life were also assessed. RESULTS: Of 501 patients registered, those eligible were randomized to TTI (n = 242) or TS (n = 240). Patient demographics and primary malignancies were similar between study arms. Overall, there was no difference between study arms in the percentage of patients with successful 30-day outcomes (TTI, 78%; TS, 71%). However, the subgroup of patients with primary lung or breast cancer had higher success with TTI than with TS (82% vs 67%). Common morbidity included fever, dyspnea, and pain. Treatment-related mortality occurred in nine TTI patients and seven TS patients. Respiratory complications were more common following TTI than TS (14% vs 6%). Respiratory failure was observed in 4% of TS patients and 8% of TTI patients, accounting for five toxic deaths and six toxic deaths, respectively. Quality-of-life measurement demonstrated less fatigue with TTI than TS. Patient ratings of comfort and safety were also higher for TTI, but there were no differences on perceived value or convenience of the procedures. CONCLUSIONS: Both methods of talc delivery are similar in efficacy; TTI may be better for patients with either a lung or breast primary. The etiology and incidence of respiratory complications from talc need further exploration.


Assuntos
Derrame Pleural Maligno/terapia , Pleurodese/métodos , Talco/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Insuflação , Masculino , Pessoa de Meia-Idade , Pleurodese/efeitos adversos , Qualidade de Vida , Recidiva , Toracoscopia , Toracostomia
18.
J Thorac Imaging ; 20(3): 214-9, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16077337

RESUMO

The risk of performing CT-guided transthoracic needle biopsy of some mediastinal and pulmonary hilar masses is increased by the presence of intervening lung. A series of patients is presented in whom a protective pneumothorax provided access for biopsy of masses in the mediastinum and pulmonary hilum. Review of Interventional Radiology records revealed 24 patients who had biopsies of mediastinum or pulmonary hilum, in whom protective pneumothorax was used, or attempted, to provide percutaneous access for biopsy. Characteristics of these patients and their procedures were reviewed. Percutaneous access to the pleural space was gained in 21/24 (88%) of patients. A protective pneumothorax was established in 19 (79%); 2 patients had pleural adhesions that prevented the lung from being displaced. The process of creating the protective pneumothorax added a mean time of 17 minutes to the procedure (range 6-30 minutes). All patients had biopsy using coaxial technique, with either a 20-gauge or 18-gauge core biopsy instrument, in addition to needle aspiration. Air leak requiring tube drainage occurred in 1/19 (5%) of patients who had a protective pneumothorax, and in 2/5 (40%) of patients in whom protective pneumothorax was not established. Percutaneous creation of a protective pneumothorax is a safe method that provides access for needle biopsy of deep lesions in the chest without traversing aerated lung.


Assuntos
Biópsia por Agulha , Pneumopatias/patologia , Doenças do Mediastino/patologia , Pneumotórax Artificial , Radiografia Intervencionista , Tomografia Computadorizada por Raios X , Distribuição de Qui-Quadrado , Feminino , Humanos , Pneumopatias/diagnóstico por imagem , Masculino , Doenças do Mediastino/diagnóstico por imagem
20.
Acad Radiol ; 22(1): 25-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25481515

RESUMO

Academic radiology is poised to play an important role in the development and implementation of quantitative imaging (QI) tools. This article, drafted by the Association of University Radiologists Radiology Research Alliance Quantitative Imaging Task Force, reviews current issues in QI biomarker research. We discuss motivations for advancing QI, define key terms, present a framework for QI biomarker research, and outline challenges in QI biomarker development. We conclude by describing where QI research and development is currently taking place and discussing the paramount role of academic radiology in this rapidly evolving field.


Assuntos
Biomarcadores/análise , Interpretação de Imagem Assistida por Computador/métodos , Técnicas de Diagnóstico Molecular/métodos , Imagem Molecular/métodos , Técnicas de Sonda Molecular , Sondas Moleculares , Animais , Humanos
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