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101.
M. TROSSAËRT P. BOISSEAU A. QUEMENER M. SIGAUD M. FOUASSIER C. TERNISIEN A. LEFRANÇOIS‐BETTEMBOURG C. TESSON C. THOMAS S. BEZIEAU 《Journal of thrombosis and haemostasis》2011,9(3):524-530
Summary. Background: In most laboratories, the severity of hemophilia A is assessed by the factor VIII activity (FVIII:C) one‐stage assay. However, comparisons of these results with those of two‐stage assays can reveal discrepancies and suggest misdiagnosis. Patients/Methods: In this monocentric study, we measured FVIII:C with two methods (one‐stage chronometric and chromogenic assays) in 307 (173 families) patients with moderate/mild hemophilia A. To compare results, we used a chronometric/chromogenic ratio. Discrepancy was defined as a ratio < 0.5 or > 1.5. We studied their putative involvement at known FVIII functional sites, their interspecies conservation status, and their spatial position within the FVIII structure. Results: Thirty‐six patients from 17 families exhibited a discrepancy between the two assays: 12 (6.9%) families had a low ratio (< 0.5), and five (2.9%) families had a high ratio (> 1.5). Qualitative deficiency was diagnosed in about 16% of the families. Molecular studies were performed in 15 of these 17 families, resulting in each case in the identification of missense mutations, including three novel mutations. We were further able to propose a pathophysiologic explanation. Conclusions: In this monocentric study, we have demonstrated a discrepancy between FVIII:C assay results in 10% of families with moderate/mild hemophilia A. The prevalence of ‘inverse’ discrepancy (i.e. low chronometric/chromogenic ratio) is high as compared with previous reports. We suggest that both FVIII:C assays are recommended in patients with moderate/mild hemophilia A for a complete biological phenotype. This could also improve our knowledge of the FVIII structure–function relationships. 相似文献
102.
Samir B. Pancholy MD FACC FSCAI Joseph Sweeney RT 《Catheterization and cardiovascular interventions》2011,78(5):809-812
Upper extremity venous access provides a safer alternative for performance of right heart catheterization compared to femoral venous access. We describe a technique to access deep veins of the upper extremity, in patients undergoing transradial catheterization, using levophase contrast venography. This technique allows the operator to access deep veins of the upper extremity without the need for additional equipment, staff or training, using traditional basic catheterization laboratory skills and equipment. © 2011 Wiley‐Liss, Inc. 相似文献
103.
B. Scott Cook MD Cleve Wilson RT Brooke Kaiser RT Raj Baljepally MD 《Catheterization and cardiovascular interventions》2017,90(6):945-947
A 45‐year old male with no prior cardiac history, presented with cardiogenic shock in the setting of an anterolateral ST elevation myocardial infarction. We first placed a 2.5 Impella for hemodynamic support, and proceeded with emergent percutaneous coronary intervention to the proximal LAD. Several hours following percutaneous coronary intervention (PCI), the patient became acutely hypotensive and an echocardiogram revealed the Impella catheter was kinked within the left ventricle. The patient was taken back to the cath lab for Impella adjustment; however, damage to the distal catheter required the Impella be exchanged. As the patient was therapeutically anticoagulated and on dual antiplatelet therapy, we modified the Impella catheter in order to maintain existing vascular access during Impella exchange. This case demonstrates our method for maintaining vascular access during Impella exchange, thereby eliminating the need for a second arterial puncture. © 2017 Wiley Periodicals, Inc. 相似文献
104.
Expanded clinical use of everolimus eluting bioresorbable vascular scaffolds for treatment of coronary artery disease 下载免费PDF全文
Roberto Diletti MD PhD Yuki Ishibashi MD PhD Cordula Felix MD Yoshinobu Onuma MD Shimpei Nakatani MD Nicolas M. van Mieghem MD PhD Eveliyn Regar MD PhD Marco Valgimigli MD PhD Peter P. de Jaegere MD PhD Nienke van Ditzhuijzen MD Jiang Ming Fam MBBS MD Jurgen M.R. Ligthart RT Mattie J. Lenzen PhD Patrick W. Serruys MD PhD Felix Zijlstra MD PhD Robert Jan van Geuns MD PhD 《Catheterization and cardiovascular interventions》2017,90(1):58-69
105.
Masanori Ozaki MS Yusuke Inoue MD PhD Tosiaki Miyati PhD DMSc Hirohumi Hata RT Sinya Mizukami RT Shotaro Komi RT Keiji Matsunaga MD Reiko Woodhams MD PhD 《Journal of magnetic resonance imaging : JMRI》2013,37(1):172-178
Purpose:
To assess the effect of motion artifact reduction on the diffusion‐weighted magnetic resonance imaging (DWI‐MRI) of the liver, we compared velocity‐compensated DWI (VC‐DWI) and VC‐DWI combined with tetrahedral gradients (t‐VC‐DWI) to conventional DWI (c‐DWI) in the assessment of apparent diffusion coefficients (ADCs) of the liver.Materials and Methods:
In 12 healthy volunteers, the liver was scanned with c‐DWI, VC‐DWI, and t‐VC‐DWI sequences. The signal‐to‐noise ratio (SNR) and ADC of the liver parenchyma were measured and compared among sequences.Results:
The image quality was visually better for t‐VC‐DWI than for the others. The SNR for t‐VC‐DWI was significantly higher than that for VC‐DWI (P < 0.05) and comparable to that for c‐DWI. ADCs in both hepatic lobes were significantly lower for t‐VC‐DWI than for c‐DWI (P < 0.01). ADC in the left lobe was significantly lower for VC‐DWI than for c‐DWI (P < 0.01). Although ADC in the left lobe was significantly higher for c‐DWI (P < 0.01), no significant differences in ADCs were found between the right and left lobes for VC‐DWI and t‐VC‐DWI.Conclusion:
The use of a t‐VC‐DWI sequence enables us to correct ADCs of the liver for artificial elevation due to cardiac motion, with preserved SNR. J. Magn. Reson. Imaging 2013;37:172–178. © 2012 Wiley Periodicals, Inc. 相似文献106.
Expert Panel on MR Safety: Emanuel Kanal MD A. James Barkovich MD Charlotte Bell MD James P. Borgstede MD William G. Bradley Jr MD PhD Jerry W. Froelich MD J. Rod Gimbel MD John W. Gosbee MD Ellisa Kuhni‐Kaminski RT Paul A. Larson MD James W. Lester Jr MD John Nyenhuis PhD Daniel Joe Schaefer PhD Elizabeth A. Sebek RN BSN Jeffrey Weinreb MD Bruce L. Wilkoff MD Terry O. Woods PhD Leonard Lucey JD Dina Hernandez BSRT 《Journal of magnetic resonance imaging : JMRI》2013,37(3):501-530
Because there are many potential risks in the MR environment and reports of adverse incidents involving patients, equipment and personnel, the need for a guidance document on MR safe practices emerged. Initially published in 2002, the ACR MR Safe Practices Guidelines established de facto industry standards for safe and responsible practices in clinical and research MR environments. As the MR industry changes the document is reviewed, modified and updated. The most recent version will reflect these changes. J. Magn. Reson. Imaging 2013;37:501–530. © 2013 Wiley Periodicals, Inc. 相似文献
107.
Rami Doukky MD MSc FACC Nathan Frogge MBA Yohannes A. Bayissa MD Gautam Balakrishnan MD Jacob M. Skelton CNMT RT Kara Confer BS Kalindi Parikh MD Russell F. Kelly MD FACC 《Journal of nuclear cardiology》2013,20(5):774-784
Background
The prognostic implications of transient ischemic dilatation (TID) of the left ventricle with otherwise normal single-photon emission computed tomography myocardial perfusion imaging (MPI) remain controversial. Whether this finding may have prognostic implications only in high-risk populations, such as patients with diabetes or manifest coronary artery disease (CAD), is uncertain.Methods
We conducted a prospective cohort study of 1,236 consecutive patients with normal 99mTc-sestamibi MPI, defined as normal perfusion (summed stress score = 0) and normal left ventricle volume and function. TID was defined as >2 standard deviations above the mean of patients with low likelihood of CAD.Results
The study subjects were followed for 27 ± 9 months. The 76 (6%) patients with TID had a greater rate of cardiac death or myocardial infarction (MI) [4 (5.3%) vs 11 (0.6%), P = .003] independent of covariates [hazard ratio = 6.4, P = .004]. This finding was entirely derived from the subgroup of 294 patients with diabetes or CAD [4 (13.3%) with TID vs 1 (0.4%) without TID, P = .001] independent of covariates. However, TID was not predictive of cardiac death or MI among the 941 patients without diabetes or CAD. Furthermore, TID was not predictive of coronary revascularization.Conclusions
This study confirms a benign prognosis of TID with otherwise normal MPI in patients without diabetes or CAD, but cautions against extending this conclusion to high-risk individuals, particularly those with diabetes or CAD. 相似文献108.
Sue C. Kaste DO Samuel L. Brady PhD Brian Yee RT ARRT Valerie J. McPherson BS Robert A. Kaufman MD Catherine A. Billups MS Najat C. Daw MD Alberto S. Pappo MD 《Cancer》2013,119(1):182-188
BACKGROUND:
It is unclear whether routine pelvic imaging is needed in patients with Wilms tumor. Thus, the primary objective of the current study was to examine the role of routine pelvic computed tomography (CT) in a cohort of pediatric patients with Wilms tumor.METHODS:
With institutional review board approval, the authors retrospectively identified 110 patients who had Wilms tumor diagnosed between January 1999 and December 2009 with surveillance imaging that continued through March 2011. The authors estimated overall survival (OS), event‐free survival (EFS), and dosimetry from dose length product (DLP) conversion to the effective dose (ED) for every CT in a subgroup of 80 patients who had CT studies obtained using contemporary scanners (2002‐2011). Metal‐oxide‐semiconductor field‐effect transistor (MOSFET) dosimeters were placed within organs of anthropomorphic phantoms to directly calculate the truncal ED. EDDLP was correlated with EDMOSFET to calculate potential pelvic dose savings.RESULTS:
Eighty patients underwent 605 CT examinations that contained DLP information, including 352 CT scans of the chest, abdomen, and pelvis; 123 CT scans of the chest and abdomen; 102 CT scans of the chest only; 18 CT scans of the abdomen and pelvis; 9 CT scans of the abdomen only; and 1 CT that was limited to the pelvis. The respective 5‐year OS and EFS estimates were 92.8% ± 3% and 2.6% ± 4.3%. Sixteen of 110 patients (15%) developed a relapse a median of 11.3 months (range, 5.0 months to 7.3 years) after diagnosis, and 4 patients died of disease recurrence. Three patients developed pelvic relapses, all 3 of which were symptomatic. The estimated ED savings from sex‐neutral CT surveillance performed at a 120‐kilovolt peak without pelvic imaging was calculated as 30.5% for the average patient aged 1 year, 30.4% for the average patient aged 5 years, 39.4% for the average patient aged 10 years, and 44.9% for the average patient aged 15 years.CONCLUSIONS:
Omitting pelvic CT from the routine, off‐therapy follow‐up of patients with Wilms tumor saved an average 30% to 45% of the ED without compromising disease detection. Cancer 2013. © 2012 American Cancer Society. 相似文献109.
Compressed sensing reconstruction for undersampled breath‐hold radial cine imaging with auxiliary free‐breathing data 下载免费PDF全文