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281.
282.
Nael K Saleh R Nyborg GK Fonseca CG Weinmann HJ Laub G Finn JP 《Journal of magnetic resonance imaging : JMRI》2007,25(1):66-72
PURPOSE: To prospectively evaluate the technical feasibility of a highly accelerated pulmonary MR perfusion protocol at 3.0T using a blood pool contrast agent in a swine model. MATERIALS AND METHODS: Twelve pigs underwent time-resolved pulmonary MR angiography (MRA) on a 3.0T MR system under anesthesia and controlled mechanical ventilation. After intravenous injection of 0.05 mmol/kg of Gadomer-17 at 4 mL/second, a fast time-resolved MRA sequence with temporal echo-sharing (three segmented k-space) and highly accelerated parallel acquisition was used to acquire 3D data sets with an in-plane resolution of 1 x 1 mm(2) (slice thickness = 6 mm) and temporal resolution of one second. Image quality was evaluated independently by two radiologists, and quantitative analysis of perfusion parameters was performed using pre-released perfusion software. RESULTS: All studies were identified by both readers as having diagnostic image quality (range = 2-3, median = 3) and there was excellent interobserver agreement (kappa = 0.89; 95% CI = 0.83, 0.95). A quantitative analysis of perfusion indices was performed, with excellent overall goodness-of-fit (chi(2) value = 1.4, degree of freedom (DF) = 1). Successfully derived perfusion parameters included the time to peak (TTP, 5.1 +/- 0.7 second), mean transit time (MTT, 6.6 +/- 0.9 second), maximal signal intensity (MSI, 1051.2 +/- 718.9 arbitrary units [A.U.]), and maximal upslope of the curve (MUS, 375.9 +/- 263.4 A.U./second). CONCLUSION: 3.0T pulmonary MR perfusion using a blood pool contrast agent in a swine model is feasible. The higher available signal-to-noise ratio (SNR) at 3.0T and the high T1 relaxivity of Gadomer-17 effectively support highly accelerated parallel acquisition, and improve the performance of time-resolved pulmonary MRA. 相似文献
283.
PURPOSE: To extend observations on intra-renal oxygenation with blood oxygen level-dependent (BOLD) MRI in human and rats to mouse kidneys imaged with a human whole-body scanner. MATERIALS AND METHODS: Renal BOLD MRI studies were performed on a 3.0T scanner using a multiple gradient-echo (mGRE) sequence with a custom-designed 2.0-cm surface coil to acquire six T(2)*-weighted images in mice (N = 8) at an in-plane resolution of 156 x 156 mum(2). BOLD MRI data were obtained before and after administration of furosemide (10 mg/kg intravenously [i.v.]). RESULTS: The mean weight of eight mice was 24.6 +/- 1.0 g. The baseline renal R(2)* (mean +/- standard error [SE]) was 28.6 +/- 2.1 seconds(-1) in the renal cortex (CO), 35.4 +/- 2.2 in the outer medulla (OM), and 21.2 +/- 2.1 seconds(-1) in the inner medulla (IM). The BOLD response to furosemide (DeltaR(2)*) was 4.1 +/- 1.4 in the CO, 10.1 +/- 2.1 seconds(-1) in the OM, and 3.4 +/- 0.8 seconds(-1) in the IM in mice. CONCLUSION: Intrarenal BOLD MR images with sufficiently high resolution can be obtained on a human whole-body scanner when combined with a small receiver coil to allow studies in mice. Both baseline R(2)* and DeltaR(2)* values following administration of furosemide were consistent with previous experience in humans and rats. 相似文献
284.
Anand K. Narayan Diego B. Lopez Randy C. Miles Brian Dontchos Efren J. Flores McKinley Glover Constance D. Lehman 《Journal of the American College of Radiology》2019,16(4):631-634
PurposeOne in five US women report that they have been victims of intimate partner violence (IPV) during their lifetime. With millions of women presenting for mammography every year, breast imaging centers may represent ideal venues to identify women at risk for IPV and refer them to appropriate support services. Our purpose was to evaluate implementation of a novel IPV screening and referral system for women presenting for mammography.MethodsA question was added to intake questionnaire (“Do you feel safe in your home?”) for adult women presenting for screening or diagnostic mammography from 2016 to 2017 at our hospital outpatient breast imaging sites. The proportion of women presenting for screening or diagnostic mammogram who felt unsafe was calculated. Bivariate logistic regression analyses were performed to compare baseline characteristics of women who stated that they felt unsafe at home versus women who did not state that they felt unsafe at home.ResultsIn all, 99,029 examinations were performed (68,158 unique patients). Of these patients, 71 stated that they felt unsafe at home (71 of 68,158, 0.1%). Women presenting for their first mammogram were more likely to report feeling unsafe at home (odds ratio 3.03, 95% confidence interval 1.31-7.06, P = .01). No differences were found in age (P = .148), ethnicity (P = .271), gravida (P = .676), parity (P = .752), age at menarche (P = .775), and history of breast cancer (P = .726).ConclusionsOur results demonstrate the feasibility of a screening and referral system for IPV in radiology departments. 相似文献
285.
《Clinical gastroenterology and hepatology》2023,21(6):1617-1626.e9
Background and AimsPrior studies have linked environmental pollutants with gastrointestinal (GI) diseases. Here, we quantify the relationships between 7 pollutants and the zip code–level incidence of irritable bowel syndrome (IBS), functional dyspepsia, inflammatory bowel diseases (IBDs), and eosinophilic esophagitis (EoE) in California.MethodsClaims in Optum’s Clinformatics Data Mart were linked with environmental exposures in California, derived from CalEnviroScreen 3.0. We identified adult patients with new diagnoses of each GI disease, and estimated claims-derived, zip code–level disease incidence rates. Two study periods were considered: 2009–2014 (International Classification of Diseases–Ninth Revision era) and 2016–2019 (International Classification of Diseases–Tenth Revision [ICD-10] era). Multivariable negative binomial regression models were used to test associations between 7 pollutants (ozone, particulate matter <2.5 μm [PM2.5], diesel emissions, drinking water contaminants, pesticides, toxic releases from industrial facilities, traffic density) and zip code–level incidence of the GI diseases along with a negative control outcome, adjusting for numerous potential confounders.ResultsZip code-level IBS incidence was associated with PM2.5 (P < .001 in both eras) and airborne toxic releases from facilities (P < .001 in both eras). An increase of 1 μg/m3 in PM2.5 or 1% in toxic releases translates to an increase in the IBS incidence rate of about 0.02 cases per 100 person-years. Traffic density and drinking water contaminant exposures were also associated with increasing IBS incidence, but these associations were not significant in both eras. Similarly, exposure to PM2.5, drinking water contaminants and airborne toxic releases from facilities were associated with functional dyspepsia incidence, though not in both eras. No significant associations were noted between pollutants and IBD or EoE incidence.ConclusionExposure to PM2.5 and airborne toxic releases from facilities are associated with higher IBS incidence among a cohort of commercially insured Californians. Environmental pollutant exposure was not associated with the incidence of IBDs and EoE in this cohort. 相似文献