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ObjectivesDual-energy computed tomography (DECT) is a recent development for detecting bone marrow edema (BME) in patients with vertebral compression fractures. The aim of this pilot study was to determine the reliability of single-source DECT in detecting vertebral BME using magnetic resonance imaging (MRI) as standard of reference.Materials and methodsNine patients with radiographic thoracic or lumbar vertebral compression fractures underwent both, DECT on a 320-row single-source scanner and 1.5 T MRI. Virtual non-calcium (VNC) images were reconstructed from the DECT volume datasets. Three blinded readers independently scored images for the presence of BME. Only vertebrae with loss of height in radiography (target vertebrae) were included in the analysis. A vertebra was counted as positive if two readers agreed on the presence of BME. Cohen’s kappa was calculated for interrater comparison. Intervertebral ratios of target and the reference vertebra were compared for CT attenuation and MR signal intensity in a reference vertebra using Spearman correlation. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated.ResultsFourteen target vertebrae with a radiographic height loss were identified; eight of them showed BME on MRI, while DECT identified BME in 7 instances. There were no false positive virtual non-calcium images, resulting in a sensitivity of 0.88 (0.75–1.0 among all readers) and specificity of 1.0 (0.81–1.0). Interrater agreement was inferior for DECT (κ = 0.63–0.89) compared to MRI (κ = 0.9–1.0). Intervertebral ratio in VNC images strongly correlated with short-tau inversion recovery (r = 0.87) and inversely with T1 (-0.89). SNR (0.2 +/− 0.2 in VNC and 16.7 +/− 7.3 in STIR) and CNR (0.2 +/− 0.3 and 7.1 +/− 6.3) values were inferior in VNC.ConclusionsDetecting BME with single-source DECT is feasible and allows detection of vertebral compression fractures with reasonably high sensitivity and specificity. However, image quality of VNC reconstructions has to be improved to achieve better interrater agreement. Nonetheless, DECT might accelerate the diagnostic work-flow in patients with vertebral compression fractures in the future and reduce the number of additional MRI examinations. 相似文献
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《Parkinsonism & related disorders》2014,20(8):907-910
BackgroundImpulse control disorders (ICDs) are a relatively recent addition to the behavioral spectrum of PD-related non-motor symptoms. Social and economic factors may play a role on the ICD phenotype of PD patients.ObjectiveThe aim of this study is to determine the prevalence and characterize the clinical profile of ICDs in a sample of low-income, low-education PD patients with no social security benefits from a Latin American country.MethodsWe included 300 consecutive PD patients and 150 control subjects. The presence of ICD and related disorders was assessed using a structured interview. After the interview and neurological evaluation were concluded, all subjects completed the Questionnaire for Impulsive-compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS).ResultsRegarding ICDs and related disorders (hobbyism-punding), 25.6% (n = 77) of patients in the PD group and 16.6% (n = 25) in the control group fulfilled criteria for at least one ICD or related disorder (p = 0.032). There was a statistically significant difference in the QUIP-RS mean score between PD and control subjects (5.6 ± 9.7 and 2.7 ± 4.21, p = 0.001). The most common ICD was compulsive eating for both PD (8.6%) and control (2.6%) groups.ConclusionsThe results of this study confirm that for this population, symptoms of an ICD are significantly more frequent in PD subjects than in control subjects. Nevertheless, socioeconomic differences may contribute to a lower overall frequency and distinct pattern of ICDs in PD patients compared with what has been reported in other countries. 相似文献
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Mireya Robledo‐Aceves Lucina Bobadilla‐Morales Estrella Lizbeth Mellín‐Sánchez Alfredo Corona‐Rivera J. Jesús Pérez‐Molina Juan José Cárdenas‐Ruiz Velasco Jorge Román Corona‐Rivera 《Congenital anomalies》2015,55(2):73-80
Mexico is recognized as a country with a high prevalence of gastroschisis, although the cause of this remains unclear. We define the prevalence and potential risk factors for gastroschisis in a public hospital from west México. A case‐control study was conducted among 270 newborns, including 90 patients with nonsyndromic gastroschisis (cases) and 180 infants without birth defects (controls), born all during the period 2009 to 2013 at the Hospital Civil de Guadalajara “Dr. Juan I. Menchaca” (Guadalajara, Mexico), from a total of 51 145 live births. Potential maternal risk factors for gastroschisis were compared using multivariate logistic regression analysis to evaluate the deviance explained by different variables of interest. The overall prevalence of gastroschisis in live births was 17.6 per 10 000 births (95% confidence interval [CI] 14.0–21.2), whereas in offspring of women ≤19 years old was 29.9 per 10 000 births (95% CI 21.9–38.0). Mothers ≤19 years (adjusted odds ratio [aOR] 2.8: 95% CI 1.5–5.1), anemia during pregnancy (aOR 10.7; 95% CI 2.0–56.9), first‐trimester exposure to hormonal contraceptives (aOR 3.7; 95% CI 1.0–13.0), and first‐trimester alcohol consumption (aOR 3.4; 95% CI 1.6–7.3), were associated with gastroschisis. Contrarily, adjusted OR for pre‐pregnancy body mass index ≥25 kg/m2 has protective odds (aOR 0.2; 95% CI 0.1–0.5). Our results suggest an increased risk for gastroschisis among mothers under the age of 20, with anemia during pregnancy, and those who used hormonal contraceptives or consumed alcohol during early pregnancy, whereas, pre‐pregnancy overweight has a protective OR, and they are discussed as clues in its pathogenesis. 相似文献
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ObjectiveTo determine the optimal monochromatic energy level for lung parenchyma analysis in spectral CT.MethodsAll 50 examinations (58% men, 64.8 ± 16yo) from an IRB-approved prospective study on single-source dual energy chest CT were retrospectively included and analyzed.Monochromatic images in lung window reconstructed every 5 keV from 40 to 140 keV were independently assessed by two chest radiologists. Based on the overall image quality and the depiction/conspicuity of parenchymal lesions, each reader had to designate for every patient the keV level providing the best diagnostic and image quality.Results72% of the examinations exhibited parenchymal lesions.Reader 1 picked the 55 keV monochromatic reconstruction in 52% of cases, 50 in 30% and 60 in 18%. Reader 2 chose 50 keV in 52% cases, 55 in 40%, 60 in 6% and 40 in 2%. The 50 and 55 keV levels were chosen by at least one reader in 64% and 76% of all patients, respectively.Merging 50 and 55 keV into one category results in an optimal setting selected by reader 1 in 82% of patients and by reader 2 in 92%, with a 74% concomitant agreement.ConclusionThe best image quality for lung parenchyma in spectral CT is obtained with the 50–55 keV monochromatic reconstructions. 相似文献
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Olivier Glehen MD PhD François N. Gilly MD PHD Florent Boutitie Jean M. Bereder MD François Quenet MD Lucas Sideris MD Baudouin Mansvelt MD Gérard Lorimier MD Simon Msika MD PhD Dominique Elias MD PhD 《Cancer》2010,116(24):5608-5618