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22.
D. J. Pennell H. G. Bogren J. Keegan D. N. Firmin S. R. Underwood 《Heart (British Cardiac Society)》1996,75(2):127-133
OBJECTIVE: The findings of magnetic resonance and x-ray angiography were compared for assessment of coronary artery stenosis in this validation study. BACKGROUND: Magnetic resonance angiography of the coronary arteries has recently been described, but there has been no comparison with x-ray angiography of localisation or assessment of important characteristics of coronary stenosis. METHODS: A breath hold, segmented k-space, 2D gradient echo imaging technique incorporating fat suppression was used in 39 patients (55 coronary stenoses) with known coronary artery disease. RESULTS: Overall, 47 stenoses (85%) were assessed by magnetic resonance (29 of 33 stenoses in the left anterior descending artery, one of one in the left main stem, 14 of 17 in the right coronary artery, and three of four in the left circumflex artery were detected). There was close agreement between magnetic resonance and x-ray angiography for the distance of the stenosis from the arterial origin (magnetic resonance mean (SD) 27 (16) mm versus x-ray angiography 27 (16) mm, P = NS, mean difference -0.2 mm). The distance to 39 stenoses (83%) agreed to within 5 mm, with increased scatter for more distal stenoses. The severity of magnetic resonance signal loss, assessed visually at the site of stenosis, varied significantly according to the percentage diameter stenosis (F = 30, P < 0.0001); stenosis severity with severe signal loss was 89 (7)%, with partial signal was 70 (16)%, and with irregular wall only 37 (11)%, with significant differences among the three groups (P < 0.001). A significant correlation was found between the proportional magnetic resonance signal loss at the stenosis and the percentage diameter stenosis severity (r = -0.67, P < 0.0001). The length of stenosis measured by magnetic resonance (6 (3) mm) was greater than by x-ray angiography (5 (2) mm, P < 0.006, mean difference +1.1 mm). Spearman's rank test showed that there was significant overestimation of stenosis length by magnetic resonance as stenosis severity increased (rs = 0.34, P < 0.02). CONCLUSIONS: Accurate localisation of coronary stenosis and a qualitative assessment of stenosis severity are possible by magnetic resonance, but stenosis length is overestimated as severity increases, probably because of disturbed patterns of flow with turbulence distal to severe stenoses. Reasonable results for the detection of coronary artery stenosis by magnetic resonance were achieved in this highly selected population, but further progress in imaging techniques is necessary before moving towards appreciable clinical application. 相似文献
23.
Christian T. Stoeck Andrew D. Scott Pedro F. Ferreira Elizabeth M. Tunnicliffe Irvin Teh Sonia Nielles‐Vallespin Kevin Moulin David E. Sosnovik Magalie Viallon Pierre Croisille Sebastian Kozerke David N. Firmin Daniel B. Ennis Jurgen E. Schneider 《Journal of magnetic resonance imaging : JMRI》2020,51(1):319-320
24.
AimTo compare outcomes regarding splinting versus casting of paediatric torus fractures in the ED with the aim of establishing the preferred treatment.MethodsEvidence was collated using electronic databases; Pubmed, Ovid, Medline and Cochrane library. Search terms included [torus fractures; buckle fractures; splinting distal radius fractures; paediatric wrist fractures; paediatric forearm fractures/injuries; cast versus splint]. Searches identified papers published between 1984 and June 2008.ResultsThe review demonstrated that children with removable splints preferred them to casts, in terms of improved physical functioning and lower pain scores reported after initial injury than those with casts. Children demonstrated this by using their wrists in the first week after injury to shower and bathe more easily. The cast group reported unscheduled visits to ED due to problems with the cast, such as discomfort or re-application of the cast from getting it wet. Using a splint will have considerable economic implications, money was found to be saved in terms of time and resource management. Radiographs taken at 4 weeks in both the cast and splint group confirmed that all fractures healed without significant change in alignment, suggesting that neither clinical nor radiographic follow-up is necessary for injury.ConclusionTorus splints in all the studies were consistently better than plaster immobilisation in terms of clinical outcome, patient preference and cost, with the exceptions of young children or children with special needs who can easily remove the device. Splinting torus fractures may reduce cost, time and resource management if used instead of casting in the ED. 相似文献
25.
TP Jain DN Srivastava RP Sahu S Thulkar S Sharma S Mittal V Dadhwal 《Journal of Medical Imaging and Radiation Oncology》2007,51(3):246-252
The aim of this study was to determine the effectiveness of uterine artery embolization (UAE) as a primary treatment method in treatment of symptomatic fibroids, whether there are any preembolization MRI characteristics of fibroid predictive of reduction in volume and assess reduction in uterine and dominant fibroid volumes using ultrasound (US) and MRI. Study was carried out in total of 32 patients aged 25–49 years (mean 40.9 years). Uterine and dominant fibroid volume were determined using US and MRI before UAE, MRI and US at 3 months and US alone at 6 and 12 months post‐UAE, supplemented by clinical evaluation at interval of 3, 6 and 12 months. Procedure was carried out through unilateral femoral puncture using poly vinyl alcohol (PVA) particles 355–500 μm in size. All 32 patients had successful procedures. Overall, 25 patients responded, giving a clinical success rate of 78.12%. Mean reduction in volume of uterus and fibroid was 33 and 59.7% and 48.9 and 75.5% on US at 3 and 12 months respectively, and 33.3 and 58.6% on MRI at 3 months. Volume reduction on US and MRI at 3 months was highly correlative. There was no statistical difference in size reduction in volume of fibroids, which were hypointense or hyperintense on T2‐weighted image (T2WI) on pre‐UAE MRI. Uterine artery embolization leads to good technical success and fibroid volume reduction. Ultrasound alone may be used for follow up of patients post‐UAE. Preprocedure signal characteristics on T2WI are not predictors of volume reduction after UAE. 相似文献
26.
J Salat-Baroux D Cornet S Alvarez J M Antoine J De Brux C Firmin C Tibi J Mandelbaum M Plachot 《Revue fran?aise de gynécologie et d'obstétrique》1988,83(10):603-606
18 patients with ovarian failure received cyclic steroid replacement therapy including estrogens and progesterone for embryo transfer. Hormonal results and endometrial histology are reported. The temporal window of endometrial receptivity 13 discussed, shedding some light on the respective role of embryo and endometrium in the implantation process. 相似文献
27.
28.
R Bhargava DN Srivastava S Thulkar M Berry NP Gupta 《Journal of Medical Imaging and Radiation Oncology》2002,46(2):170-173
We present the study of colour duplex Doppler ultrasonography on Indian patients with non‐vasculogenic erectile dysfunction. Patients with a history suggestive of psychogenic impotence along with a normal clinical response to intracavernosal papaverine were presumed to have non‐vasculogenic erectile dysfunction. In our patients, the incidence of psychogenic impotence was much higher and the mean age of patients presenting with erectile dysfunction was lower as compared to patients from developed countries reported in research. The Doppler flowmetry showed much higher mean peak systolic velocities (PSVs) with a negative correlation between age and PSV. End diastolic velocity, resistive index and acceleration time values conformed to the literature. 相似文献
29.
Floating thrombus in the aorta 总被引:2,自引:0,他引:2
A review of the literature shows that there are few reported cases of embolism or thrombus in a nonaneurysmal, effectively normal aorta with no other underlying reason for thrombus formation in the aorta. We report a case of a large, floating thrombus in the descending aorta lumen and discuss surgical and management options. 相似文献
30.
The congenital anomaly of aortopulmonary window is rare. Its combination with interruption of the aortic arch has been previously
recognized and reported in infants and children. Early and complete repair of such a congenital anomaly may prevent progression
to cardiac failure and premature death. We describe the successful echocardiographic diagnosis and one-stage surgical repair,
via a median sternotomy, of the aortopulmonary window, interrupted aortic arch, patent ductus arteriosus, and patent foramen
ovale in a 3-day-old neonate. The literature is also reviewed. 相似文献