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First-trimester screening for trisomy-21 using a simplified method to assess the presence or absence of the fetal nasal bone 总被引:4,自引:0,他引:4
Orlandi F Rossi C Orlandi E Jakil MC Hallahan TW Macri VJ Krantz DA 《American journal of obstetrics and gynecology》2005,192(4):1107-1111
OBJECTIVE: To determine the benefit of including nasal bone assessment in addition to standard first-trimester markers (nuchal translucency, free beta human chorionic gonadotropin and pregnancy-associated plasma protein A) as a screening test for Down syndrome, using a strict criterion for classification of nasal bone absence. STUDY DESIGN: Nasal bone assessment was conducted in 2411 patients with crown-rump length between 45 and 84 mm, including 15 patients with Down syndrome. A patient was considered to have an absent nasal bone only if there was no evidence of present nasal bone. Unlike other studies, nasal bone was classified as present when there was evidence of a thin echogenic line under the skin. Simulation studies were conducted to assess the detection rate and false-positive rate of a combined first-trimester screening protocol including nasal bone assessment. RESULTS: There were 9 of 2396 (0.4%) unaffected cases with absent nasal bone (95% confidence interval 0.2%, 0.7%) and 8 of 15 (53.3%) Down syndrome cases (95% confidence interval 26.6%, 78.7%). Using a 1 in 250 risk cut-off, the detection rate of standard first-trimester screening was 87%, with a false-positive rate of 4.3%. Incorporating nasal bone measurement improved the detection rate of Down syndrome to 90% and reduced the false-positive rate to 2.5%. CONCLUSION: The use of a strict criterion to determine nasal bone absence leads to fewer cases classified as absent and may simplify the implementation of nasal bone as a marker for first-trimester screening, resulting in lower false-positives and higher detection, compared with other current screening protocols. 相似文献
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Krantz D Goetzl L Simpson JL Thom E Zachary J Hallahan TW Silver R Pergament E Platt LD Filkins K Johnson A Mahoney M Hogge WA Wilson RD Mohide P Hershey D Wapner R;First Trimester Maternal Serum Biochemistry Fetal Nuchal Translucency Screening 《American journal of obstetrics and gynecology》2004,191(4):1452-1458
OBJECTIVE: The purpose of this study was to determine the association between first-trimester trisomy 21 screening markers (free human chorionic gonadotropin-beta [hCG], pregnancy-associated plasma protein A [PAPP-A], and nuchal translucency) and adverse pregnancy outcome. STUDY DESIGN: This was a cohort study of 8012 patients enrolled in a National Institute of Child Health and Human Development-sponsored study of first-trimester trisomy 21 and 18 screening. Trisomy 21 and 18 risk results and individual marker levels in unaffected pregnancies and pregnancies with adverse outcomes were evaluated. RESULTS: PAPP-A <1st percentile (OR 5.4, 95% CI 2.8-10.3) and PAPP-A <5th percentile (OR 2.7, 95% CI 1.9-3.9) and free beta-hCG <1st percentile (OR 2.7, 95% CI 1.3-5.9) were associated with increased risk of intrauterine growth restriction (IUGR) with positive predictive values of 24.1%, 14.1%, and 14.3%, respectively. PAPP-A <5th percentile (OR 2.3 95% CI 1.1-4.7) and nuchal translucency >99th percentile (OR 3.5, 95% CI 1.1-11.3) were associated with increased risk of preterm delivery before 34 weeks. Increased risk at screening for trisomy 21 and 18 identified 16 of the 29 other chromosomal abnormalities (55%). Low free beta-hCG, low PAPP-A, and increased nuchal translucency were all associated with an increased rate of fetal abnormality. CONCLUSION: Extreme values of first-trimester free beta-hCG, PAPP-A, and nuchal translucency are all associated with adverse outcomes. The especially high predictive value for IUGR of PAPP-A levels below the 1st percentile suggests that patients within this group may benefit from increased surveillance for this condition. 相似文献
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Hallahan TW Krantz DA Macri JN 《Obstetrics and gynecology》2003,102(2):413; author reply 413-413; author reply 414
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Anorexia nervosa is an increasingly common chronic psychiatric disorder with a multitude of medical complications. Most of these complications are reversible if there is timely restoration of body weight. A few of them, particularly osteoporosis, refeeding complications, and cardiac arrhythmia, are potentially much more serious. In the end, a multidisciplinary team approach with input from a primary care provider who is familiar with these medical sequelae, together with psychiatric and dietary expertise, can effectuate a successful outcome. 相似文献
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Valentini V Piermattei A Morganti AG Gambacorta MA Azario L Macchia G Deodato F Cilla S Pepe D Grimaldi L Dinapoli N Cellini N 《Rays》2003,28(3):293-298
In the last two decades there was a radical change in radiotherapy setup. The growing availability of CT equipment and console for computer-aided treatment planning setup enabled the use of advanced technologies as conformal 3D radiation therapy in most centers. In particular in 1987 virtual simulation was proposed for setup. During its use a number of application modalities appeared. Virtual simulation in some centers is applied alone while in others it is associated with conventional simulation. However, from numerous reports published in last years it seems that virtual simulation significantly improves treatment quality independently of radical or palliative intent and of the size of treated volumes (high doses to small volumes or wide shaped fields). Some studies stressed that virtual simulation could significantly shorten treatment planning times with consequent cost reduction. The use of virtual simulation evidenced associated problems and in particular setup limitations due to the CT gantry size, the need to up-date the conventional modalities of setup verification according to the new technologies and more generally to up-date quality assurance procedures in an advanced technological setting. Finally there was the self-evident need of a better knowledge of the anatomy on axial sections, of tumor spread routes in particular. 相似文献
69.
Krantz C 《Pediatric nursing》2001,27(6):567-571
Misconceptions about childhood fevers heighten parents' concerns leading to frequent use of health care services. Designing, piloting, and evaluating nursing interventions to demystify parents' phobia of fevers are imperative. An evidence-based fever anticipatory guidance tool was designed to assist parents by: dispelling misconceptions, teaching proper care of their febrile child and appropriate use of antipyretics, and providing a list of serious signs that warrant medical attention. Concepts of the Health Belief Model (HBM) are applied to parent behavior to promote a greater understanding of their actions in the face of childhood fever. Informing consumers with accurate and consistent information has direct implications for changing practice in the hospital and community. 相似文献
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