The goal of this study was to examine the cross-sectional associations of cardiovascular risk factors with left ventricular (LV) geometry and systolic function measured by cardiac magnetic resonance ...imaging (MRI) in the Multiethnic Study of Atherosclerosis (MESA).
Cardiovascular risk factors including hypertension, smoking, and obesity are known to be associated with increased LV mass, but less is known about the association of risk factors with LV systolic function, particularly in populations without clinical cardiovascular disease.
Participants were from 4 racial/ethnic groups and were free of clinical cardiovascular disease. Blood pressure, health habits, body mass index, lipid levels, and glucose abnormalities were assessed and MRI exams performed at baseline (n = 4,869). Multivariable linear regression was used to model the association of risk factors with LV mass, end-diastolic volume, stroke volume, ejection fraction, and cardiac output.
The mean age was 62 years, and 52% of the participants were women. After adjustment for sociodemographic variables and height, higher systolic blood pressure and body mass index were associated with larger LV mass and volumes. Current smoking and diabetes were associated with greater LV mass (+7.7 g, 95% confidence interval CI +5.5 to +9.9 and +3.5 g, 95% CI +1.2 to +5.8, respectively), and with lower stroke volume (-1.9 ml, 95% CI -3.3 to -0.5 and -4.5 ml, 95% CI -6.0 to -3.0, respectively) and lower ejection fraction (-1.6%, 95% CI -2.1 to -1.0 and -0.8%, 95% CI -1.5 to -0.2, respectively).
In this cohort free of clinical cardiovascular disease, modifiable risk factors were associated with subclinical alterations in LV size and systolic function as detected by cardiac MRI.
Modeling 3D facial shape from DNA Claes, Peter; Liberton, Denise K; Daniels, Katleen ...
PLOS genetics,
03/2014, Letnik:
10, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Human facial diversity is substantial, complex, and largely scientifically unexplained. We used spatially dense quasi-landmarks to measure face shape in population samples with mixed West African and ...European ancestry from three locations (United States, Brazil, and Cape Verde). Using bootstrapped response-based imputation modeling (BRIM), we uncover the relationships between facial variation and the effects of sex, genomic ancestry, and a subset of craniofacial candidate genes. The facial effects of these variables are summarized as response-based imputed predictor (RIP) variables, which are validated using self-reported sex, genomic ancestry, and observer-based facial ratings (femininity and proportional ancestry) and judgments (sex and population group). By jointly modeling sex, genomic ancestry, and genotype, the independent effects of particular alleles on facial features can be uncovered. Results on a set of 20 genes showing significant effects on facial features provide support for this approach as a novel means to identify genes affecting normal-range facial features and for approximating the appearance of a face from genetic markers.
It is unknown whether the observed increase in computed tomography pulmonary angiography (CTPA) utilization has resulted in increased detection of pulmonary emboli (PEs) with a less severe disease ...spectrum.
Trends in utilization, diagnostic yield, and disease severity were evaluated for 4,048 consecutive initial CTPAs performed in adult patients in the emergency department of a large urban academic medical center between 1/1/2004 and 10/31/2009. Transthoracic echocardiography (TTE) findings and peak serum troponin levels were evaluated to assess for the presence of PE-associated right ventricular (RV) abnormalities (dysfunction or dilatation) and myocardial injury, respectively. Statistical analyses were performed using multivariate logistic regression.
268 CTPAs (6.6%) were positive for acute PE, and 3,780 (93.4%) demonstrated either no PE or chronic PE. There was a significant increase in the likelihood of undergoing CTPA per year during the study period (odds ratio OR 1.05, 95% confidence interval CI 1.04-1.07, P<0.01). There was no significant change in the likelihood of having a CTPA diagnostic of an acute PE per year (OR 1.03, 95% CI 0.95-1.11, P = 0.49). The likelihood of diagnosing a less severe PE on CTPA with no associated RV abnormalities or myocardial injury increased per year during the study period (OR 1.39, 95% CI 1.10-1.75, P = 0.01).
CTPA utilization has risen with no corresponding change in diagnostic yield, resulting in an increase in PE detection. There is a concurrent rise in the likelihood of diagnosing a less clinically severe spectrum of PEs.
To retrospectively assess possible clinical predictors of metastatic disease to the brain in patients with non-small cell lung carcinoma (NSCLC).
Institutional review board approval was obtained, ...informed consent was waived, and data and other information were obtained prior to implementation of HIPAA. A review was performed of 264 patients (mean age, 65 years; 158 men and 106 women) with NSCLC who had undergone imaging studies of the chest and head. Hierarchical logistic regression was used to determine the predicted probability of metastatic disease to the brain as a function of patient age and sex and of size, cell type, peripheral versus central location, and lymph node stage of the primary NSCLC.
Ninety-five (36%) patients had evidence of metastatic disease to the brain. Mean diameter of the primary tumors was 4.0 cm +/- 2.2 (standard deviation). Cell types included adenocarcinoma (136 52% patients), undifferentiated (68 26% patients), and squamous (47 18% patients), for which metastatic disease to the brain occurred in 43%, 41%, and 13% (P = .003) of patients, respectively. The predicted probability of metastatic disease to the brain correlated positively with size of the primary tumor (P < .001), cell type (adenocarcinoma and undifferentiated vs squamous, P = .001), and lymph node stage (P < .017) but did not correlate with age, sex, or primary tumor location. For primary adenocarcinoma without lymph node spread, the predicted probabilities of metastatic disease to the brain from 2- and 6-cm primary tumors were .14 (95% confidence interval: .06, .27) and .72 (95% confidence interval: .48, .88), respectively (P < .02).
The probability of metastatic disease to the brain from primary NSCLC is correlated with size of the primary tumor, cell type, and intrathoracic lymph node stage.
To determine radiation doses from coronary computed tomographic (CT) angiography performed by using a 320-detector row volume scanner and evaluate how the effective dose depends on scan mode and the ...calculation method used.
Radiation doses from coronary CT angiography performed by using a volume scanner were determined by using metal-oxide-semiconductor field-effect transistor detectors positioned in an anthropomorphic phantom physically and radiographically simulating a male or female human. Organ and effective doses were determined for six scan modes, including both 64-row helical and 280-row volume scans. Effective doses were compared with estimates based on the method most commonly used in clinical literature: multiplying dose-length product (DLP) by a general conversion coefficient (0.017 or 0.014 mSv.mGy(-1).cm(-1)), determined from Monte Carlo simulations of chest CT by using single-section scanners and previous tissue-weighting factors.
Effective dose was reduced by up to 91% with volume scanning relative to helical scanning, with similar image noise. Effective dose, determined by using International Commission on Radiological Protection publication 103 tissue-weighting factors, was 8.2 mSv, using volume scanning with exposure permitting a wide reconstruction window, 5.8 mSv with optimized exposure and 4.4 mSv for optimized 100-kVp scanning. Estimating effective dose with a chest conversion coefficient resulted in a dose as low as 1.8 mSv, substantially underestimating effective dose for both volume and helical coronary CT angiography.
Volume scanning markedly decreases coronary CT angiography radiation doses compared with those at helical scanning. When conversion coefficients are used to estimate effective dose from DLP, they should be appropriate for the scanner and scan mode used and reflect current tissue-weighting factors. (c) RSNA, 2010.
To assess for change in the 1990s in the failure of detection at chest radiography of potentially resectable non-small cell lung cancer (NSCLC) lesions compared with experience in the previous ...decade.
From 1993 to 2001, an observational cohort was identified that consisted of 40 instances of NSCLC evident retrospectively at chest radiography but undetected by a radiologist at a time when the cancer was potentially resectable for cure. Sizes and locations of the tumors were assessed. Pearson chi(2) testing was performed to compare the sex distribution of lung cancer in the present series with population data for the sex distribution of lung cancer in the United States during the present study.
Twenty-five (62%) undetected NSCLCs were in men and 15 (38%) were in women, yielding a ratio not significantly different from that for the sex distribution of NSCLC according to national data (chi(2) = 0.22, P =.64). Median patient age was 62 years (range, 37-87 years). Median diameter of the missed cancers was 1.9 cm. Missed cancers were most commonly located in the upper lobes (right, 45%; left, 28%; total, 72%), especially in the apical and posterior segments/subsegments (60% of all the missed cancers). A clavicle obscured 22% of the missed cancers. Eighty-five percent of the missed cancers were in peripheral locations.
Potentially resectable NSCLC lesions missed at chest radiography were characterized by predominantly peripheral (85%) and upper lobe (72%) locations and by apical and posterior segmental/subsegmental locations in an upper lobe (60%). Distribution by sex of the missed cancers was comparable to national data for NSCLC. The missed cancers had a median diameter of 1.9 cm.
Coronary computed tomographic angiography (CCTA) is associated with high radiation dose to the female breasts. Bismuth breast shielding offers the potential to significantly reduce dose to the ...breasts and nearby organs, but the magnitude of this reduction and its impact on image quality and radiation dose have not been evaluated.
Radiation doses from CCTA to critical organs were determined using metal-oxide-semiconductor field-effect transistors positioned in a customized anthropomorphic whole-body dosimetry verification phantom. Image noise and signal were measured in regions of interest (ROIs) including the coronary arteries.
With bismuth shielding, breast radiation dose was reduced 46%-57% depending on breast size and scanning technique, with more moderate dose reduction to the heart, lungs, and esophagus. However, shielding significantly decreased image signal (by 14.6 HU) and contrast (by 28.4 HU), modestly but significantly increased image noise in ROIs in locations of coronary arteries, and decreased contrast-to-noise ratio by 20.9%.
While bismuth breast shielding can significantly decrease radiation dose to critical organs, it is associated with an increase in image noise, decrease in contrast-to-noise, and changes tissue attenuation characteristics in the location of the coronary arteries.
Triple-rule-out computed tomographic angiography (TRO CTA), performed to evaluate the coronary arteries, pulmonary arteries, and thoracic aorta, has been associated with high radiation exposure. The ...use of sequential scanning for coronary computed tomographic angiography reduces the radiation dose. The application of sequential scanning to TRO CTA is much less well defined. We analyzed the radiation dose and image quality from TRO CTA performed at a single outpatient center, comparing the scans from a period during which helical scanning with electrocardiographically controlled tube current modulation was used for all patients (n = 35) and after adoption of a strategy incorporating sequential scanning whenever appropriate (n = 35). Sequential scanning was able to be used for 86% of the cases. The sequential-if-appropriate strategy, compared to the helical-only strategy, was associated with a 61.6% dose decrease (mean dose-length product of 439 mGy × cm vs 1,144 mGy × cm and mean effective dose of 7.5 mSv vs 19.4 mSv, respectively, p <0.0001). Similarly, a 71.5% dose reduction occurred among the 30 patients scanned with the sequential protocol compared to the 40 patients scanned with the helical protocol using either strategy (326 mGy × cm vs 1,141 mGy × cm and 5.5 mSv vs 19.4 mSv, respectively, p <0.0001). Although the image quality did not differ between the strategies, a nonstatistically significant trend was seen toward better quality in the sequential protocol than in the helical protocol. In conclusion, approaching TRO CTA with a diagnostic strategy of sequential scanning, as appropriate, can offer a marked reduction in the radiation dose while maintaining the image quality.
Abstract Objectives This study sought to determine the impact of quantity and location of aortic valve calcification (AVC) on paravalvular regurgitation (PVR) and rates of post-dilation (PD) ...immediately after transcatheter aortic valve replacement (TAVR). Background The impact of AVC in different locations within the aortic valve complex is incompletely understood. Methods This study analyzed 150 patients with severe, symptomatic aortic stenosis who underwent TAVR. Total AVC volume scores were calculated from contrast-enhanced multidetector row computed tomography imaging. AVC was divided by leaflet sector and region (Leaflet, Annulus, left ventricular outflow tract LVOT), and a combination of LVOT and Annulus (AnnulusLVOT). Asymmetry was assessed. Receiver-operating characteristic analysis was performed with greater than or equal to mild PVR and PD as classification variables. Logistic regression was performed. Results Quantity of and asymmetry of AVC for all regions of the aortic valve complex predicted greater than or equal to mild PVR by receiver-operating characteristic analysis (area under the curve = 0.635 to 0.689), except Leaflet asymmetry. Receiver-operating characteristic analysis for PD was significant for quantity and asymmetry of AVC in all regions, with higher area under the curve values than for PVR (area under the curve = 0.648 to 0.741). On multivariable analysis, Leaflet and AnnulusLVOT calcification were independent predictors of both PVR and PD regardless of multidetector row computed tomography area cover index. Conclusions Quantity and asymmetry of AVC in all regions of the aortic valve complex predict greater than or equal to mild PVR and performance of PD, with the exception of Leaflet asymmetry. Quantity of AnnulusLVOT and Leaflet calcification independently predict PVR and PD when taking into account multidetector row computed tomography area cover index.
The purpose of this article is to review the origins of the classic teaching on pulmonary tuberculosis, its evolution in the modern literature, and the evidence that led to its demise.
Use of ...molecular epidemiologic techniques that entail DNA finger-printing has led to the discovery that the radiographic appearance of pulmonary tuberculosis does not depend on the time since infection. It has been confirmed that the upper lobe cavitary disease typical in adults is the disease of the immunocompetent host, whereas lower lung zone disease, adenopathy, and effusions, which are uncommon in adults, are the hallmarks of tuberculosis in an immunocompromised host.
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