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41.
Girish B Nair Craig J Galban Sayf Al-Katib Robert Podolsky Maarten van den Berge Craig Stevens Edward Castillo 《The British journal of radiology》2021,94(1118)
Objective:To evaluate CT-ventilation imaging (CTVI) within a well-characterized, healthy cohort with no respiratory symptoms and examine the correlation between CTVI and concurrent pulmonary function test (PFT).Methods:CT scans and PFTs from 77 Caucasian participants in the NORM dataset (clinicaltrials.gov ) were analyzed. CTVI was generated using the robust Integrated Jacobian Formulation (IJF) method. IJF estimated total lung capacity (TLC) was computed from CTVI. Bias-adjusted Pearson’s correlation between PFT and IJF-based TLC was computed.Results:IJF- and PFT-measured TLC showed a good correlation for both males and females [males: 0.657, 95% CI (0.438–0.797); females: 0.667, 95% CI (0.416–0.817)]. When adjusting for age, height, smoking, and abnormal CT scan, correlation moderated [males: 0.432, 95% CI (0.129–0.655); females: 0.540, 95% CI (0.207–0.753)]. Visual inspection of CTVI revealed participants who had functional defects, despite the fact that all participant had normal high-resolution CT scan.Conclusion:In this study, we demonstrate that IJF computed CTVI has good correlation with concurrent PFT in a well-validated patient cohort with no respiratory symptoms.Advances in knowledge:IJF-computed CTVI’s overall numerical robustness and consistency with PFT support its potential as a method for providing spatiotemporal assessment of high and low function areas on volumetric non-contrast CT scan. NCT00848406相似文献
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B.R. Mussmann S.D. Mørup P.M. Skov S. Foley A.S. Brenøe F. Eldahl G.M. Jørgensen H. Precht 《Radiography》2021,27(1):1-7
IntroductionOrgan-based tube current modulation (OBTCM) is designed for anterior dose reduction in Computed Tomography (CT). The purpose was to assess dose reduction capability in chest CT using three organ dose modulation systems at different kVp settings. Furthermore, noise, diagnostic image quality and tumour detection was assessed.MethodsA Lungman phantom was scanned with and without OBTCM at 80–135/140 kVp using three CT scanners; Canon Aquillion Prime, GE Revolution CT and Siemens Somatom Flash. Thermo-luminescent dosimeters were attached to the phantom surface and all scans were repeated five times. Image noise was measured in three ROIs at the level of the carina. Three observers visually scored the images using a fivestep scale. A Wilcoxon Signed-Rank test was used for statistical analysis of differences.ResultsUsing the GE revolution CT scanner, dose reductions between 1.10 mSv (12%) and 1.56 mSv (24%) (p < 0.01) were found in the anterior segment and no differences posteriorly and laterally. Total dose reductions between 0.64 (8%) and 0.91 mSv (13%) were found across kVp levels (p < 0.00001). Maximum noise increase with OBTCM was 0.8 HU. With the Canon system, anterior dose reductions of 6–10% and total dose reduction of 0.74–0.76 mSv across kVp levels (p < 0.001) were found with a maximum noise increase of 1.1 HU. For the Siemens system, dose increased by 22–51% anteriorly; except at 100 kVp where no dose difference was found. Noise decreased by 1 to 1.5 HU.ConclusionOrgan based tube current modulation is capable of anterior and total dose reduction with minimal loss of image quality in vendors that do not increase posterior dose.Implications for practiceThis research highlights the importance of being familiar with dose reduction technologies. 相似文献
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Michel Bénézech 《Annales médico-psychologiques》2021,179(3):227-228
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目的分析并探究双侧延髓内侧梗死(BMMI)的血管病因、临床表现、MRI特征和预后,以期提高BMMI的早期诊断率.方法对青岛大学附属烟台毓璜顶医院诊治的14例BMMI患者临床资料进行分析.结果BMMI血管病因以动脉粥样硬化为主;临床症状表现为四肢瘫痪、舌瘫、感觉异常、头晕、构音障碍、饮水呛咳等,危重时出现呼吸衰竭.头颅DWI示双侧延髓内侧可呈特征性"心型"、"Y"字型、"V"字型或倒"八"字型高信号影.出院NIHSS评分、卒中进展(尤其呼吸衰竭)为BMMI的预后不良因素.结论BMMI临床少见,临床表现多样,预后较差;头颅MRI为其主要的影像学检查,有助于早期诊断. 相似文献
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R. García-Ramos D. Santos-García A. Alonso-Cánovas M. Álvarez-Sauco B. Ares A. Ávila N. Caballol F. Carrillo F. Escamilla Sevilla E. Freire J.C. Gómez Esteban I. Legarda L. López Manzanares E. López Valdés I. Martínez-Torres M. Mata I. Pareés B. Pascual-Sedano J.C. Martínez Castrillo 《Neurología (Barcelona, Spain)》2021,36(2):149-158
IntroductionThe main challenge of Parkinson's disease in women of childbearing age is managing symptoms and drugs during pregnancy and breastfeeding. The increase in the age at which women are having children makes it likely that these pregnancies will become more common in future.ObjectivesThis study aims to define the clinical characteristics of women of childbearing age with Parkinson's disease and the factors affecting their lives, and to establish a series of guidelines for managing pregnancy in these patients.ResultsThis consensus document was developed through an exhaustive literature search and a discussion of the available evidence by a group of movement disorder experts from the Spanish Society of Neurology.ConclusionsParkinson's disease affects all aspects of sexual and reproductive health in women of childbearing age. Pregnancy should be well planned to minimise teratogenic risk. A multidisciplinary approach should be adopted in the management of these patients in order to take all relevant considerations into account. 相似文献
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Andreas Glenthj Lasse H. Jakobsen Henrik Sengelv Syed A. Ahmad Kristian Qvist Annika Rewes Christian B. Poulsen Ulrik M. Overgaard Ingolf Mlle Marianne T. Severinsen Casper N. Strandholdt Jack Maibom Annette R. Kodahl Jesper Ryg Pernille Ravn Isik S. Johansen Sren N. Hels Sren Jensen‐Fangel Jacek Kisielewicz Lothar Wiese Marie Helleberg Ole Kirk Michael R. Clausen Henrik Frederiksen 《European journal of haematology》2021,106(1):72-81
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