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1.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
2.
Paediatric dacryocystorhinostomy 总被引:1,自引:0,他引:1
KN Hakin FRCS FRCOphth TJ Sullivan FRACO FRACS A Sharma FCOphth † RAN Welham FRCS FCOphth † 《Clinical & experimental ophthalmology》1994,22(4):231-235
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease. 相似文献
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Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
6.
Dr. Michele Musci MD H. Siniawski MD PhD C. Knosalla MD PhD O. Grauhan MD PhD Y. Weng MD PhD M. Pasic MD PhD R. Meyer MD PhD R. Hetzer MD PhD 《Clinical research in cardiology》2006,95(5):247-253
Summary
Aims This study investigated the early and mid–term results following valve replacement with the new Shelhigh? stentless bioprosthesis made entirely of biological material in patients with active infective endocarditis (AIE).
Material and methods Between 02/2000 and 12/2004, 164 patients (n = 122 men, mean age 59, 18–85 years) received implantation of an AIE Shelhigh? stentless bioprosthesis in the aortic, mitral, tricuspid or pulmonary position. A total of 119 patients (72.6%) had native
AIE and 45 (27.4%) prosthetic AIE. A large proportion of the patients reached the operating room in a condition of cardiac
decompensation: 37 (22.6%) patients were intubated, 40 (24.4%) had protracted septic shock and 41 (25.0%) required intensive
catecholamine treatment. Surgery was regarded as urgent in 94 patients (57.4%) and was performed as an emergency procedure
in 70 (42.6%). The mean follow–up time is 1.5 ± 0.11 years (range, 5 months to 5.2 years). Echocardiographic follow–up examinations
were performed early postoperatively and after 12 months.
Results In terms of the operative indication, we found a highly significant difference in the survival rate between patients who were
operated on urgently vs in an emergency. In patients who died within 30 days, the main cause of death was septic multiorgan
failure (67.6%). Only three patients required reoperation due to reinfection of the Shelhigh? bioprostheses; this represents a reinfection rate of 1.8% in relation to the whole cohort. The postoperative echocardiographic
examinations showed the Shelhigh? valves to have very good hemodynamics without relevant pressure gradients.
Conclusion Our experience in the use of Shelhigh? bioprostheses in patients with native and prosthetic endocarditis show the early and mid–term results, in particular the
low reinfection rate and the good hemodynamics, to be comparable with the results achieved using homografts. Since these prostheses
are readily available and their implantation straightforward, they are increasingly being used in patients with endocarditis.
These promising results need to verified in the long term.
This paper was presented at a lecture held at the 71st annual meeting of the German Society for Cardiology, Mannheim, 31. March—2. April 2005.
Disclosure Form: The following study discloses my relationship with any corporate sponsor that might relate in some way to
the subject presented. 相似文献
7.
Michele Musci Henryk Siniawski Miralem Pasic Yuguo Weng Antonio Loforte Susanne Kosky Charles Yankah Roland Hetzer 《European journal of cardio-thoracic surgery》2008,34(2):410-417
OBJECTIVE: We investigated outcomes after surgical therapy in patients with active infective endocarditis (AIE) with regard to survival in relation to surgical urgency, valve position, number of valves implanted and abscess formation. We aimed to identify independent risk factors for early mortality. METHODS AND RESULTS: Two hundred and fifty-five patients received Shelhigh bioprostheses between February 2000 and March 2007. A total of 74.1% had native and 25.9% prosthetic AIE. Surgery was regarded as urgent in 57.3% and as an emergency procedure in 38.4%. There was a highly significant difference in survival rate between patients who were operated on urgently versus in an emergency (p<0.0001), between single and double valve replacement (p=0.0206) and between patients with and without abscess formation (p=0.0245). There were two cases of early reinfection (0.78%) and six of late reinfection (2.35%) leading to re-operation. CONCLUSIONS: The survival of patients differs significantly in dependence on their surgical urgency. Better outcome could have been achieved if patients had been referred earlier for surgery and operated upon before heart failure or septic shock developed. Long-term survival was better in patients without abscess formation. The low reinfection rate of Shelhigh bioprostheses in AIE is promising and the early and mid-term results achieved need to be verified in the long-term course. 相似文献
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