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BACKGROUND: Dynamic myocardial computed tomography perfusion (CTP) is a novel imaging technique that increases the applicability of CT for cardiac imaging; however, the scanning requires a substantial radiation dose. PURPOSE: To investigate the feasibility of dose reduction in dynamic CTP by comparing all-heartbeat acquisitions to periodic skipping of heartbeats. MATERIAL AND METHODS: We retrieved imaging data of 38 dynamic CTP patients and created new datasets with every fourth, third or second beat (Skip1:4, Skip1:3, Skip1:2, respectively) removed. Seven observers evaluated the resulting images and perfusion maps for perfusion deficits. The mean blood flow (MBF) in each of the 16 myocardial segments was compared per skipped-beat level, normalized by the respective MBF for the full dose, and averaged across patients. The number of segments/cases whose MBF was <1.0â mL/g/min were counted. RESULTS: Out of 608 segments in 38 cases, the total additional number of false-negative (FN) segments over those present in the full-dose acquisitions and the number of additional false-positive cases were shown as acquisition (segment [%], case): Skip1:4: 7 (1.2%, 1); Skip1:3: 12 (2%, 3), and Skip1:2: 5 (0.8%, 2). The variability in quantitative MBF analysis in the repeated analysis for the reference condition resulted in 8 (1.3%) additional FN segments. The normalized results show a comparable MBF across all segments and patients, with relative mean MBFs as 1.02 ± 0.16, 1.03 ± 0.25, and 1.06 ± 0.30 for the Skip1:4, Skip1:3, and Skip1:2 protocols, respectively. CONCLUSION: Skipping every second beat acquisition during dynamic myocardial CTP appears feasible and may result in a radiation dose reduction of 50%. Diagnostic performance does not decrease after removing 50% of time points in dynamic sequence.
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Imagem de Perfusão do Miocárdio , Doses de Radiação , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio/métodos , Idoso , Estudos de Viabilidade , Tomografia Computadorizada por Raios X/métodos , Adulto , Frequência Cardíaca/fisiologia , Idoso de 80 Anos ou maisRESUMO
OBJECTIVE: This study aimed to determine whether lower values of feature-tracking cardiovascular magnetic resonance (CMR)-derived left atrial reservoir strain (LARS) and impaired left ventricular (LV) global longitudinal strain (GLS) were associated with the presence of symptoms and long-term prognosis in patients with SSc. METHODS: A total of 100 patients {54 [interquartile range (IQR) 46-64] years, 42% male} with SSc who underwent CMR imaging at two tertiary referral centres were included. All patients underwent analysis of LARS and LV GLS using feature-tracking on CMR and were followed-up for the occurrence of all-cause mortality. RESULTS: The median LV GLS was -21.8% and the median LARS was 36%. On multivariable logistic regression, LARS [odds ratio (OR) 0.964 per %, 95% CI 0.929, 0.998, P = 0.049] was independently associated with New York Heart Association (NYHA) class II-IV heart failure symptoms. Over a median follow-up of 37 (21-62) months, a total of 24 (24%) patients died. Univariable Cox regression analysis demonstrated that LARS [hazard ratio (HR) 0.94 per 1%, 95% CI 0.91, 0.97, P < 0.0001) and LV GLS (HR 1.10 per %, 95% CI 1.03, 1.17, P = 0.005) were associated with all-cause mortality, while LV ejection fraction was not. Likelihood ratio tests demonstrated that LARS provided incremental value over prognostically important clinical and imaging parameters, including late gadolinium enhancement. CONCLUSION: In patients with SSc, LARS was independently associated with the presence of NYHA class II-IV heart failure symptoms. Although both LARS and LV GLS were associated with all-cause mortality, only LARS provided incremental value over all evaluated variables known to be prognostically important in patients with SSc.
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Insuficiência Cardíaca , Escleroderma Sistêmico , Feminino , Humanos , Masculino , Meios de Contraste , Gadolínio , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Valor Preditivo dos Testes , Prognóstico , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/diagnóstico por imagem , Volume Sistólico , Função Ventricular Esquerda , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Dynamic myocardial computed tomography perfusion (CTP) is a novel technique able to depict cardiac ischemia. PURPOSE: To evaluate the impact of a four-dimensional noise reduction filter (similarity filter [4D-SF]) on image quality in dynamic CTP imaging, allowing for substantial radiation dose reduction. MATERIAL AND METHODS: Dynamic CTP datasets of 30 patients (16 women) with suspected coronary artery disease, acquired with a 320-slice CT system, were retrieved, reconstructed with the deep learning-based algorithm of the system (DLR), and filtered with the 4D-SF. For each case, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in six regions of interest (33-38mm2) were calculated before and after filtering, in four-chamber and short-axis views, and t-tested. Furthermore, six radiologists of different expertise evaluated subjective image preference by answering five visual grading analysis-type questions (regarding acceptable level of noise, absence of artifacts, natural appearance, cardiac contour sharpness, diagnostic acceptability) using a 5-point scale. The results were analyzed using visual grade characteristics (VGC) and intraclass correlation coefficient (ICC). RESULTS: Mean SNR in four-chamber view (unfiltered vs. filtered) were: septum=4.1 ± 2.1 versus 7.6 ± 5.6; lateral wall=4.5 ± 2.0 versus 8.0 ± 4.9; CNRseptum=16.6 ± 8.9 versus 31.7 ± 28; lateral wall=16.2 ± 8.9 versus 31.3 ± 28.9. Similar results were obtained in short-axis view. The perceived filtered image quality indicated decreased noise (VGCAUC=0.96) and artifacts (0.65), improved natural appearance (0.59), cardiac contour sharpness (0.74), and diagnostic acceptability (0.78). The inter-observer variability was excellent (ICC=0.79). All results were statistically significant (P < 0.05). CONCLUSION: Similarity filtering after DLR improves image quality, possibly enabling dose reduction in dynamic CTP imaging in patient with suspected chronic coronary syndrome.
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Doença da Artéria Coronariana , Imagem de Perfusão do Miocárdio , Humanos , Feminino , Imagem de Perfusão do Miocárdio/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Miocárdio , Coração/diagnóstico por imagem , Razão Sinal-Ruído , Algoritmos , Tomografia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Doses de RadiaçãoRESUMO
BACKGROUND: Autologous haematopoietic stem cell transplantation (HSCT) improves survival in systemic sclerosis (SSc) with poor prognosis, but is hampered by treatment-related mortality (TRM). OBJECTIVE: To evaluate event-free survival (EFS), TRM, response to treatment, disease progression and patient characteristics associated with events. METHODS: All patients treated with HSCT for SSc in The Netherlands until 2017 (n=92) were included. Data on skin involvement (modified Rodnan skin score (mRSS), pulmonary function (forced vital capacity (FVC) and diffusion capacity of the lungs for carbon monoxide (DLCO)), extent of interstitial lung disease on high-resolution CT using Goh scores and left ventricular ejection fraction (LVEF) were collected at baseline, 1, 2 and 5 years. Occurrence of events, defined as death or major organ failure, were collected until 2019. As control, a comparison between patients treated with cyclophosphamide (CYC) and patients with HSCT who participated in the Autologous Stem Cell Transplantation International Scleroderma (ASTIS) trial was performed. RESULTS: Median follow-up was 4.6 years. EFS estimates at 5, 10 and 15 years were 78%, 76% and 66%, respectively. Twenty deaths occurred. Mean FVC, DLCO, mRSS and Goh scores all improved significantly. Disease progression occurred in 22 patients. Frequency of TRM decreased over time and occurred more often in males. Events were independently associated with male sex, LVEF <50% and older age. In ASTIS, patients treated with HSCT (n=23) 7 events occurred versus 13 in the CYC group (n=22). CONCLUSION: Our data confirm long-term efficacy of HSCT in improving survival, skin and lung involvement in SSc. Male sex, lower LVEF and older age at baseline were identified as risk factors for events.
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Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Escleroderma Sistêmico/terapia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Intervalo Livre de Progressão , Fatores de Risco , Escleroderma Sistêmico/mortalidade , Transplante Autólogo/efeitos adversosRESUMO
Objectives Nurses must contribute to the development of professional practice and thereby improve quality of care by using their research abilities. Therefore, learning communities comprised of nurses, students and teachers were created in a hospital. Methods A qualitative descriptive methodology was used. Three learning communities were purposefully selected, and members were asked open-ended questions about their learning and activities in multiple data collection sessions. Data were analyzed by means of an inductive process. Results Both individually and collectively, members learned about research in general, research terminology and methods. They learned about asking questions and critical thinking, and, specifically through collective learning, they learned about the differences between education practices. Activities were carried out primarily to continue personal learning. Conclusions Learning within the learning communities was mainly research-oriented and therefore potentially suitable for enhancing research ability. Implications are offered to support the formulation of community activities.
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Bacharelado em Enfermagem/métodos , Relações Interprofissionais , Estudantes de Enfermagem/psicologia , Pensamento , Adaptação Psicológica , Humanos , Pesquisa em Educação em Enfermagem , Resolução de Problemas , Pesquisa Qualitativa , Apoio Social , Estudantes de Enfermagem/estatística & dados numéricosRESUMO
Background Dual-energy CT iodine maps are used to detect pulmonary embolism (PE) with CT angiography but require dedicated hardware. Subtraction CT, a software-only solution, results in iodine maps with high contrast-to-noise ratios. Purpose To compare the use of subtraction CT versus dual-energy CT iodine maps to CT angiography for PE detection. Materials and Methods In this prospective study ( https://clinicaltrials.gov , NCT02890706), 274 participants suspected of having PE underwent precontrast CT followed by contrast material-enhanced dual-energy CT angiography between July 2016 and April 2017. Iodine maps from dual-energy CT were derived. Subtraction maps (contrast-enhanced CT minus precontrast CT) were calculated after motion correction. Truth was established by expert consensus. A total of 75 randomly selected participants with and without PE (1:1 ratio) were evaluated by three radiologists and six radiology residents (blinded to final diagnosis) for the presence of PE using three types of CT: CT angiography alone, dual-energy CT, and subtraction CT. The partial area under the receiver operating characteristic curve (AUC) for the clinically relevant specificity region (maximum partial AUC, 0.11) was compared by using multireader multicase variance. A P value less than or equal to .025 was considered indicative of a significant difference due to multiple comparisons. Results There were 35 men and 40 women in the reader study (mean age, 63 years ± 12 [standard deviation]). The pooled sensitivities were not different (P ≥ .31 among techniques) (95% confidence intervals [CIs]: 67%, 89% for CT angiography; 72%, 91% for dual-energy CT; 70%, 91% for subtraction CT). However, pooled specificity was higher for subtraction CT (95% CI: 100%, 100%) than for CT angiography (95% CI: 89%, 97%) or dual-energy CT (95% CI: 89%, 98%) (P < .001). Partial AUCs for the average observer improved equally when adding iodine maps (subtraction CT [0.093] vs CT angiography [0.088], P = .03; dual-energy CT [0.094] vs CT angiography, P = .01; dual-energy CT vs subtraction CT, P = .68). Average reading times were equivalent (range, 97-101 seconds; P ≥ .41) among techniques. Conclusion Subtraction CT iodine maps had greater specificity than CT angiography alone in pulmonary embolism detection. Subtraction CT had comparable diagnostic performance to that of dual-energy CT, without the need for dedicated hardware. © RSNA, 2019 Online supplemental material is available for this article.
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Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste , Iodo , Embolia Pulmonar/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE. The objective of this study was to compare the image quality of iodine maps derived from subtraction CT and from dual-energy CT (DECT) in patients with suspected pulmonary embolism (PE). SUBJECTS AND METHODS. In this prospective study conducted between July 2016 and April 2017, consecutive patients with suspected PE underwent unenhanced CT at 100 kV and dual-energy pulmonary CT angiography at 100 and 140 kV on a dual-source scanner. The scanner was set to generate subtraction and DECT iodine maps at similar radiation doses. In 55 patients (30 women, 25 men; mean age ± SD, 63.4 ± 11.9 years old), various subjective image quality criteria including diagnostic acceptability were rated on a 5-point scale by four radiologists and a radiology resident. In 29 patients (17 women, 12 men; mean age, 62.4 ± 11.7 years old) with confirmed perfusion defects, the signal-difference-to-noise ratio (SDNR) between perfusion defects and adjacent normally perfused parenchyma was measured in corresponding ROIs on subtraction and DECT iodine maps. McNemar and Wilcoxon signed-rank tests were used for statistical comparisons. RESULTS. Diagnostic acceptability was rated excellent or good in a mean of 67% (range, 31-80%) of subtraction CT studies and 36% (5-69%) of DECT studies (p < 0.05 for four of the five radiologists), mainly because of fewer artifacts on subtraction CT. Mean SDNR was marginally higher for subtraction CT than for DECT (18.6 vs 17.1, p = 0.06) and was significantly higher in the upper lobes (21.8 vs 17.9, p < 0.05). CONCLUSION. Radiologist-judged image quality of pulmonary iodine maps was higher for subtraction CT than for DECT with similar to higher SDNR. Subtraction CT is a software-only solution, so it may be an attractive alternative to DECT for depicting perfusion defects.
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Pulmonary arterial (PA) flow is abnormal after the Fontan operation and is marked by a lack of pulsatility. We assessed the effects of this abnormal flow on the size and function of the PA's in Fontan patients in long-term serial follow-up. Twenty-three Fontan patients with serial follow-up were included. Median age was 11.1 (9.5-16.0) years at baseline and 15.5 (12.5-22.7) years at follow-up. Median follow-up duration was 4.4 (4.0-5.8) years. Flow and size of the left pulmonary artery were determined using phase-contrast MRI. From this wall shear stress (WSS), distensibility and pulsatility were determined. A group of healthy peers was included for reference. Flow and pulsatility were significantly lower in patients than in controls (p < 0.001). Mean area was comparable in patients and controls, but distensibility was significantly higher in controls (p < 0.001). Mean and peak WSS were significantly lower in Fontan patients (p < 0.001). Between baseline and follow-up, there was a significant increase in normalized flow (15.1 (14.3-19.1) to 18.7 (14.0-22.6) ml/s/m(2), p = 0.023). Area, pulsatility, distensibility and WSS did not change, but there was a trend toward a lower mean WSS (p = 0.068). Multivariable regression analysis showed that flow, area and age were important predictors for WSS. WSS in Fontan patients is decreased compared to healthy controls and tends to decrease further with age. Pulsatility and distensibility are significantly lower compared to healthy controls. Pulmonary artery size, however, is not significantly different from healthy controls and long-term growth after Fontan operation is proportionate to body size.
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Velocidade do Fluxo Sanguíneo , Técnica de Fontan/efeitos adversos , Artéria Pulmonar/diagnóstico por imagem , Fluxo Pulsátil , Adolescente , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Seguimentos , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Análise Multivariada , Países Baixos , Artéria Pulmonar/fisiopatologia , Adulto JovemRESUMO
There is a need for person-centred approaches and empowerment of staff within the residential care for older people; a movement called 'culture change'. There is however no single path for achieving culture change. With the aim of increasing understandings about cultural change processes and the promotion of cultural values and norms associated with person-centred practices, this article presents an action research project set on a unit in the Netherlands providing care for older people with dementia. The project is presented as a case study. This study examines what has contributed to the improvement of participation of older people with dementia in daily occupational and leisure activities according to practitioners. Data was collected by participant observation, interviews and focus groups. The results show that simultaneous to the improvement of the older people's involvement in daily activities a cultural transformation took place and that the care became more person-centred. Spontaneous interactions and responses rather than planned interventions, analysis and reflection contributed to this. Furthermore, it proved to be beneficial that the process of change and the facilitation of that process reflected the same values as those underlying the cultural change. It is concluded that changes arise from dynamic, interactive and non-linear processes which are complex in nature and difficult to predict and to control. Nevertheless, managers and facilitators can facilitate such change by generating movement through the introduction of small focused projects that meet the stakeholders' needs, by creating conditions for interaction and sense making, and by promoting the new desired cultural values.
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Assistência à Saúde Culturalmente Competente , Atividades de Lazer , Assistência Centrada no Paciente , Idoso , Demência/terapia , Grupos Focais , Pesquisa sobre Serviços de Saúde , Humanos , Países Baixos , Casas de Saúde , Estudos de Casos Organizacionais , Inovação OrganizacionalRESUMO
PURPOSE: To examine the factors that affect inter- and intraobserver agreement for pulmonary nodule type classification on low-radiation-dose computed tomographic (CT) images, and their potential effect on patient management. MATERIALS AND METHODS: Nodules (n = 160) were randomly selected from the Dutch-Belgian Lung Cancer Screening Trial cohort, with equal numbers of nodule types and similar sizes. Nodules were scored by eight radiologists by using morphologic categories proposed by the Fleischner Society guidelines for management of pulmonary nodules as solid, part solid with a solid component smaller than 5 mm, part solid with a solid component 5 mm or larger, or pure ground glass. Inter- and intraobserver agreement was analyzed by using Cohen κ statistics. Multivariate analysis of variance was performed to assess the effect of nodule characteristics and image quality on observer disagreement. Effect on nodule management was estimated by differentiating CT follow-up for ground-glass nodules, solid nodules 8 mm or smaller, and part-solid nodules smaller than 5 mm from immediate diagnostic work-up for solid nodules larger than 8 mm and part-solid nodules 5 mm or greater. RESULTS: Pair-wise inter- and intraobserver agreement was moderate (mean κ, 0.51 [95% confidence interval, 0.30, 0.68] and 0.57 [95% confidence interval, 0.47, 0.71]). Categorization as part-solid nodules and location in the upper lobe significantly reduced observer agreement (P = .012 and P < .001, respectively). By considering all possible reading pairs (28 possible combinations of observer pairs × 160 nodules = 4480 possible agreements or disagreements), a discordant nodule classification was found in 36.4% (1630 of 4480), related to presence or size of a solid component in 88.7% (1446 of 1630). Two-thirds of these discrepant readings (1061 of 1630) would have potentially resulted in different nodule management. CONCLUSION: There is moderate inter- and intraobserver agreement for nodule classification by using current recommendations for low-radiation-dose CT examinations of the chest. Discrepancies in nodule categorization were mainly caused by disagreement on the size and presence of a solid component, which may lead to different management in the majority of cases with such discrepancies. (©) RSNA, 2015.
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Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/terapia , Tomografia Computadorizada por Raios X , Humanos , Variações Dependentes do ObservadorRESUMO
PURPOSE: To evaluate the added value of computer-aided detection (CAD) for lung nodules on chest radiographs when radiologists have bone-suppressed images (BSIs) available. MATERIALS AND METHODS: Written informed consent was waived by the institutional review board. Selection of study images and study setup was reviewed and approved by the institutional review boards. Three hundred posteroanterior (PA) and lateral chest radiographs (189 radiographs with negative findings and 111 radiographs with a solitary nodule) in 300 subjects were selected from image archives at four institutions. PA images were processed by using a commercially available CAD, and PA BSIs were generated. Five radiologists and three residents evaluated the radiographs with BSIs available, first, without CAD and, second, after inspection of the CAD marks. Readers marked locations suspicious for a nodule and provided a confidence score for that location to be a nodule. Location-based receiver operating characteristic analysis was performed by using jackknife alternative free-response receiver operating characteristic analysis. Area under the curve (AUC) functioned as figure of merit, and P values were computed with the Dorfman-Berbaum-Metz method. RESULTS: Average nodule size was 16.2 mm. Stand-alone CAD reached a sensitivity of 74% at 1.0 false-positive mark per image. Without CAD, average AUC for observers was 0.812. With CAD, performance significantly improved to an AUC of 0.841 (P = .0001). CAD detected 127 of 239 nodules that were missed after evaluation of the radiographs together with BSIs pooled over all observers. Only 57 of these detections were eventually marked by the observers after review of CAD candidates. CONCLUSION: CAD improved radiologists' performance for the detection of lung nodules on chest radiographs, even when baseline performance was optimized by providing lateral radiographs and BSIs. Still, most of the true-positive CAD candidates are dismissed by observers.
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Diagnóstico por Computador/métodos , Radiografia Torácica/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
AIMS: Systemic sclerosis (SSc) is characterized by vasculopathy, inflammation, and fibrosis, and carries one of the worst prognoses if patients also develop pulmonary arterial hypertension (PAH). Although PAH is a known prognosticator, patients with SSc-PAH demonstrate disproportionately high mortality, presumably due to cardiac involvement. In this cross-sectional study, the relationship between cardiac involvement revealed by cardiovascular magnetic resonance (CMR) and systemic microvascular disease severity measured with nailfold capillaromicroscopy (NCM) in patients with SSc-PAH is evaluated and compared with patients with idiopathic PAH (IPAH). METHODS AND RESULTS: Patients with SSc-PAH and IPAH underwent CMR, echocardiography, and NCM with post-occlusive reactivity hyperaemia (PORH) testing on the same day. CMR imaging included T2 (oedema), native, and post-contrast T1 mapping to measure the extracellular volume fraction (ECV, fibrosis) and adenosine-stress-perfusion imaging measuring the relative myocardial upslope (microvascular coronary perfusion). Measures of peripheral microvascular function were related to CMR indices of oedema, fibrosis, and myocardial perfusion. SSc-PAH patients (n = 20) had higher T2 values and a trend towards a higher ECV, compared with IPAH patients (n = 5), and a lower nailfold capillary density (NCD) and reduced capillary recruitment after PORH. NCD correlated with ECV and T2 (r = -0.443 and -0.464, respectively, P < 0.05 for both) and with markers of diastolic dysfunction on echocardiography. PORH testing, but not NCD, correlated with the relative myocardial upslope (r = 0.421, P < 0.05). CONCLUSION: SSc-PAH patients showed higher markers of cardiac fibrosis and inflammation, compared with IPAH patients. These markers correlated well with peripheral microvascular dysfunction, suggesting that SSc-driven inflammation and vasculopathy concurrently affect peripheral microcirculation and the heart. This may contribute to the disproportionate high mortality in SSc-PAH.
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Imagem Cinética por Ressonância Magnética , Escleroderma Sistêmico , Humanos , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/diagnóstico por imagem , Escleroderma Sistêmico/fisiopatologia , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Transversais , Imagem Cinética por Ressonância Magnética/métodos , Adulto , Hipertensão Arterial Pulmonar/fisiopatologia , Hipertensão Arterial Pulmonar/diagnóstico por imagem , Ecocardiografia/métodos , Microcirculação , Índice de Gravidade de Doença , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/etiologia , Angioscopia Microscópica , Idoso , PrognósticoRESUMO
OBJECTIVES: To determine the influence of local contrast optimisation on diagnostic accuracy and perceived suspiciousness of digital screening mammograms. METHODS: Data were collected from a screening region in the Netherlands and consisted of 263 digital screening cases (153 recalled,110 normal). Each case was available twice, once processed with a tissue equalisation (TE) algorithm and once with local contrast optimisation (PV). All cases had digitised previous mammograms. For both algorithms, the probability of malignancy of each finding was scored independently by six screening radiologists. Perceived case suspiciousness was defined as the highest probability of malignancy of all findings of a radiologist within a case. Differences in diagnostic accuracy of the processing algorithms were analysed by comparing the areas under the receiver operating characteristic curves (A(z)). Differences in perceived case suspiciousness were analysed using sign tests. RESULTS: There was no significant difference in A(z) (TE: 0.909, PV 0.917, P = 0.46). For all radiologists, perceived case suspiciousness using PV was higher than using TE more often than vice versa (ratio: 1.14-2.12). This was significant (P <0.0083) for four radiologists. CONCLUSIONS: Optimisation of local contrast by image processing may increase perceived case suspiciousness, while diagnostic accuracy may remain similar. KEY POINTS: Variations among different image processing algorithms for digital screening mammography are large. Current algorithms still aim for optimal local contrast with a low dynamic range. Although optimisation of contrast may increase sensitivity, diagnostic accuracy is probably unchanged. Increased local contrast may render both normal and abnormal structures more conspicuous.
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Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Detecção Precoce de Câncer/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Intensificação de Imagem Radiográfica/métodos , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/prevenção & controle , Feminino , Humanos , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Variações Dependentes do Observador , Prevalência , Medição de Risco , Fatores de RiscoRESUMO
OBJECTIVE: Women with Turner syndrome (TS) are at increased risk of aortic dissection, which is a life-threatening event associated with aortic dilation. Knowledge on the development of aortic dilation over time remains limited. This study aims to describe the prevalence of aortic dilation, to find associated factors and to study aortic growth in women with TS. METHODS: In this prospective multicentre cohort study, consecutive adult women with genetically proven TS included between 2014 and 2016 underwent ECG-triggered multiphase CT angiography at baseline and after 3 years. Aortic diameters were measured at seven levels of the thoracic aorta using double oblique reconstruction and indexed for body surface area. Ascending aortic dilation was defined as an aortic size index >20 mm/m2. Aorta-related and cardiovascular events were collected. Statistical analysis included linear and logistic regression and linear mixed effects models. RESULTS: The cohort consisted of 89 women with a median age of 34 years (IQR: 24-44). Ascending aortic dilation was found in 38.2% at baseline. At baseline, age (OR: 1.08 (95% CI 1.03 to 1.13), p<0.001), presence of bicuspid aortic valve (BAV) (OR: 7.09 (95% CI 2.22 to 25.9), p=0.002) and systolic blood pressure (OR: 1.06 (95% CI 1.02 to 1.11), p=0.004) were independently associated with ascending aortic dilation. During a median follow-up of 3.0 (2.4-3.6) years (n=77), significant aortic growth was found only at the sinotubular junction (0.20±1.92 mm, p=0.021). No aortic dissection occurred, one patient underwent aortic surgery and one woman died. CONCLUSIONS: In women with TS, ascending aortic dilation is common and associated with age, BAV and systolic blood pressure. Aortic diameters were stable during a 3-year follow-up, apart from a significant yet not clinically relevant increase at the sinotubular junction, which may suggest a more benign course of progression than previously reported.
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Doenças da Aorta , Dissecção Aórtica , Doença da Válvula Aórtica Bicúspide , Síndrome de Turner , Adulto , Humanos , Feminino , Adulto Jovem , Síndrome de Turner/complicações , Síndrome de Turner/diagnóstico , Síndrome de Turner/epidemiologia , Valva Aórtica/diagnóstico por imagem , Estudos de Coortes , Estudos Prospectivos , Dilatação/efeitos adversos , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/epidemiologia , Doenças da Aorta/etiologia , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/epidemiologia , Dissecção Aórtica/etiologia , Dilatação Patológica , Estudos RetrospectivosRESUMO
Introduction: Right ventricular (RV) function is of particular importance in systemic sclerosis (SSc), since common SSc complications, such as interstitial lung disease and pulmonary hypertension may affect RV afterload. Cardiovascular magnetic resonance (CMR) is the gold standard for measuring RV function. CMR-derived RV and right atrial (RA) strain is a promising tool to detect subtle changes in RV function, and might have incremental value, however, prognostic data is lacking. Therefore, the aim of this study was to evaluate the prognostic value of RA and RV strain in SSc. Methods: In this retrospective study, performed at two Dutch hospitals, consecutive SSc patients who underwent CMR were included. RV longitudinal strain (LS) and RA strain were measured. Unadjusted cox proportional hazard regression analysis and likelihood ratio tests were used to evaluate the association and incremental value of strain parameters with all-cause mortality. Results: A total of 100 patients (median age 54 [46-64] years, 42% male) were included. Twenty-four patients (24%) died during a follow-up of 3.1 [1.8-5.2] years. RA reservoir [Hazard Ratio (HR) = 0.95, 95% CI 0.91-0.99, p = 0.009] and conduit strain (HR = 0.93, 95% CI 0.88-0.98, p = 0.008) were univariable predictors of all-cause mortality, while RV LS and RA booster strain were not. RA conduit strain proved to be of incremental value to sex, atrial fibrillation, NYHA class, RA maximum volume indexed, and late gadolinium enhancement (p < 0.05 for all). Conclusion: RA reservoir and conduit strain are predictors of all-cause mortality in SSc patients, whereas RV LS is not. In addition, RA conduit strain showed incremental prognostic value to all evaluated clinical and imaging parameters. Therefore, RA conduit strain may be a useful prognostic marker in SSc patients.
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PURPOSE: In lung cancer patients with multiple lesions, the differentiation between metastases and second primary tumours has significant therapeutic and prognostic implications. The aim of this retrospective study was to investigate the potential of (18)F-FDG PET to discriminate metastatic disease from second primary lung tumours. METHODS: Of 1,396 patients evaluated by the thoracic oncology group between January 2004 and April 2009 at the Radboud University Nijmegen Medical Centre, patients with a synchronous second primary lung cancer were selected. Patients with metastatic disease involving the lungs served as the control group. Maximum standardized uptake values (SUVs) measured with (18)F-FDG PET were determined for two tumours in each patient. The relative difference between the SUVs of these tumours (∆SUV) was determined and compared between the second primary group and metastatic disease group. Receiver-operating characteristic (ROC) curve analysis was performed to determine the sensitivity and specificity of the ∆SUV for an optimal cut-off value. RESULTS: A total of 37 patients (21 metastatic disease, 16 second primary cancer) were included for analysis. The ∆SUV was significantly higher in patients with second primary cancer than in those with metastatic disease (58 vs 28%, respectively, p < 0.001). The area under the ROC curve was 0.81 and the odds ratio for the optimal cut-off was 18.4. CONCLUSION: SUVs from (18)F-FDG PET images can be helpful in differentiating metastatic disease from second primary tumours in patients with synchronous pulmonary lesions. Further studies are warranted to confirm the consistency of these results.
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Fluordesoxiglucose F18 , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Segunda Neoplasia Primária/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Idoso , Idoso de 80 Anos ou mais , Transporte Biológico , Diagnóstico Diferencial , Feminino , Fluordesoxiglucose F18/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/metabolismo , Curva ROC , Radiografia Torácica , Estudos RetrospectivosRESUMO
AIMS: The aim of this study was to evaluate the possible value of dobutamine stress cardiac magnetic resonance imaging (CMR) to predict adverse outcome in Tetralogy of Fallot (TOF) patients. METHODS AND RESULTS: In previous prospective multicentre studies, TOF patients underwent low-dose dobutamine stress CMR (7.5 µg/kg/min). Subsequently, during regular-care patient follow-up, patients were assessed for reaching the composite endpoint (cardiac death, arrhythmia-related hospitalization, or cardioversion/ablation, VO2 max ≤65% of predicted). A normal stress response was defined as a decrease in end-systolic volume (ESV) and increase in ejection fraction. The relative parameter change during stress was calculated as relative parameter change = [(parameterstress - parameterrest)/parameterrest] * 100. The predictive value of dobutamine stress CMR for the composite endpoint was determined using time-to-event analyses (Kaplan-Meier) and Cox proportional hazard analysis. We studied 100 patients [67 (67%) male, median age at baseline CMR 17.8 years (interquartile range 13.5-34.0), age at TOF repair 0.9 years (0.6-2.1)]. After a median follow-up of 8.6 years (6.7-14.1), 10 patients reached the composite endpoint. An abnormal stress response (30% vs. 4.4%, P = 0.021) was more frequently observed in composite endpoint patients. Also in endpoint patients, the relative decrease in right ventricular ESV decreased less during stress compared with the patients without an endpoint (-17 ± 15 vs. -26 ± 13 %, P = 0.045). Multivariable analyses identified an abnormal stress response (hazard ratio 10.4; 95% confidence interval 2.5-43.7; P = 0.001) as predictor for the composite endpoint. CONCLUSION: An abnormal ventricular response to dobutamine stress is associated with adverse outcome in patients with repaired TOF.
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Dobutamina , Imageamento por Ressonância Magnética , Tetralogia de Fallot , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Estudos Prospectivos , Tetralogia de Fallot/diagnóstico por imagem , Tetralogia de Fallot/cirurgia , Adulto JovemRESUMO
OBJECTIVE: Marfan syndrome (MFS) is a connective tissue disorder associated with severe cardiovascular morbidity and mortality. It is unknown if aorta complications in MFS are associated with progressive pulmonary artery (PA) dilatation. METHODS: We measured the PA diameter on routine magnetic resonance imaging in a population of MFS patients seen in our specialised centre with follow up of diameters as well as the outcome. RESULTS: PA dilatation was defined as an increase in diameter of 2 mm or more, and 71 patients (44%) of our total cohort (n = 162) met this criterion; mean follow up between two scans was 8.6 years (standard deviation (SD) ± 2.7 years). Furthermore, 28 patients suffered from dissections, of which 14 had a type A dissection, 10 had a type B dissection, and 4 patients suffered from both. Of those who suffered from dissection, 64% (18 out of 28) had a dilatation of the PA, versus 39% (53 out of 134) in the patient group without a dissection (p < 0.05). There was a significant association between type B dissection and descending aorta diameter (OR 1.14; 95% CI 1.05-1.24 p < 0.01) and PA dilatation (OR 1.69; 95% CI 1.03-2.77 p = 0.04). In the multivariable analysis the final model for type B dissection, only systolic blood pressure (OR 1.06; 95% CI 1.01-1.11 p = 0.02) and PA dilatation were statistically significant (OR 1.85; 95% CI 1.10-3.12 p = 0.02) while descending aorta diameter was not. CONCLUSIONS: We report an association between progressive PA dilatation and type B dissection. Our findings encourage a renewed interest in PA dimensions in MFS.
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BACKGROUND: Women with Turner syndrome (TS) are at increased risk of aortic dissection, which is related to ascending aortic diameter. However, the relation between aortic diameter and outcome is not well determined. This study evaluates the prevalence of aortic dilatation, the growth rate of the aorta and the risk of aortic complications in adults with TS. METHODS: Single centre, retrospective study of all women with TS followed with a strict protocol in an outpatient TS clinic. Aortic diameters were analysed using advanced imaging. The primary outcome was a combined endpoint of aortic-related mortality, aortic dissection and preventive aortic surgery. The secondary endpoint was aortic growth and prevalence of aortic dilatation, defined as an aortic size index >20 mm/m2 at baseline. RESULTS: At least one cardiac MR/CT was available in 268 women with TS, having median age of 28.7 (IQR: 21.3-39.7) years. Aortic dilatation was present in 22%. Linear regression identified independent factors associated with larger aortic diameters: age (coefficient=0.23; p<0.001), hypertension (coefficient=2.7; p<0.001), bicuspid aortic valve (coefficient=3.3; p<0.001), 45XO karyotype (coefficient=1.7; p=0.002), weight (coefficient=0.075; p<0.001) and growth hormone treatment (coefficient=1.4; p=0.044). During follow-up (6.8±3.2 years), five women (2%) reached the primary endpoint (two dissections, three aortic surgery). Women withmore than one scan (n=171; 1015 patient-years follow-up), the median aortic growth was 0.20 (IQR: 0.00-0.44) mm/year. In multivariate analysis, aortic growth was not associated with baseline aortic diameter or other variables. CONCLUSIONS: Aortic dilatation is common and known associations were confirmed in large adult TS cohort However, aortic dissection, related mortality and preventive aortic surgery are rare. Growth hormone treatment in childhood was associated with aortic dimensions.
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Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/etiologia , Dissecção Aórtica/etiologia , Síndrome de Turner/complicações , Adulto , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/epidemiologia , Aneurisma da Aorta Torácica/diagnóstico , Aneurisma da Aorta Torácica/epidemiologia , Ecocardiografia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Imagem Cinética por Ressonância Magnética , Países Baixos/epidemiologia , Prevalência , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Tomografia Computadorizada por Raios X , Síndrome de Turner/diagnóstico , Adulto JovemRESUMO
PURPOSE: To compare human observers to a mathematically derived computer model for differentiation between malignant and benign pulmonary nodules detected on baseline screening computed tomography (CT) scans. METHODS: A case-cohort study design was chosen. The study group consisted of 300 chest CT scans from the Danish Lung Cancer Screening Trial (DLCST). It included all scans with proven malignancies (n = 62) and two subsets of randomly selected baseline scans with benign nodules of all sizes (n = 120) and matched in size to the cancers, respectively (n = 118). Eleven observers and the computer model (PanCan) assigned a malignancy probability score to each nodule. Performances were expressed by area under the ROC curve (AUC). Performance differences were tested using the Dorfman, Berbaum and Metz method. Seven observers assessed morphological nodule characteristics using a predefined list. Differences in morphological features between malignant and size-matched benign nodules were analyzed using chi-square analysis with Bonferroni correction. A significant difference was defined at p < 0.004. RESULTS: Performances of the model and observers were equivalent (AUC 0.932 versus 0.910, p = 0.184) for risk-assessment of malignant and benign nodules of all sizes. However, human readers performed superior to the computer model for differentiating malignant nodules from size-matched benign nodules (AUC 0.819 versus 0.706, p < 0.001). Large variations between observers were seen for ROC areas and ranges of risk scores. Morphological findings indicative of malignancy referred to border characteristics (spiculation, p < 0.001) and perinodular architectural deformation (distortion of surrounding lung parenchyma architecture, p < 0.001; pleural retraction, p = 0.002). CONCLUSIONS: Computer model and human observers perform equivalent for differentiating malignant from randomly selected benign nodules, confirming the high potential of computer models for nodule risk estimation in population based screening studies. However, computer models highly rely on size as discriminator. Incorporation of other morphological criteria used by human observers to superiorly discriminate size-matched malignant from benign nodules, will further improve computer performance.