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Tania Pereira Jose Muguruza Virtu Mária Ester Vilaprinyo Albert Sorribas Elvira Fernandez Jose Manuel Fernandez-Armenteros Juan Antonio Baena Ferran Rius Angels Betriu Francesc Solsona Rui Alves 《Ultrasound in medicine & biology》2018,44(12):2780-2792
Adventitial vasa vasorum are physiologic microvessels that nourish artery walls. In the presence of cardiovascular risk factors, these microvessels proliferate abnormally. Studies have reported that they are the first stage of atheromatous disease. Contrast-enhanced ultrasound (CEUS) of the carotid allows direct, quantitative and non-invasive visualization of the adventitial vasa vasorum. Hence, the development of computer-assisted methods that speed image analysis and eliminate user subjectivity is important. We developed methods for automatic analyses and quantification of vasa vasorum neovascularization in CEUS and tested these methods in a cohort of 186 individuals, 63 of whom were healthy volunteers. We implemented alternative automatic strategies for using the images to stratify patients according to their risk group and compare the strategies with respect to diagnostic performance. An automatic single-parameter strategy performs less effectively than the corresponding Arcidiacono method based on manual interpretation of the images (68 < area under the receiver operating characteristic curve [AUROC] for the manual Arcidiacono method < 82; 60 < AUROC for the automatic single-parameter strategy < 63). However, by use of additional image parameters, an automatic multiparameter strategy has significantly improved performance with respect to the manual Arcidiacono method (78 < AUROC < 90). The automatic multiparameter strategy is a valuable alternative to the manual Arcidiacono method, improving both diagnostic speed and diagnostic accuracy. 相似文献
93.
Julio González Martín-Moro Marco Sales-Sanz Noelia Oblanca-Llamazares Angel Bustos-García Jose Carlos Méndez-Cendón Eduardo Fandiño 《Orbit (Amsterdam, Netherlands)》2018,37(4):306-308
A 47-year-old woman was diagnosed with dural carotid cavernous fistula (CCF) in her right eye (RE). Scans of the choroid using Spectralis optic coherence tomography (OCT) demonstrated significant asymmetry in subfoveal choroidal thickness (RE 451 μm, left eye (LE) 367 μm). This asymmetry disappeared after the fistula was embolizated through the ophthalmic artery (RE 341 μm; LE 340 μm). This case suggests that OCT should be considered as an ancillary test in the diagnosis of CCF. 相似文献
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P. Bell 《Acta chirurgica Belgica》2013,113(2):141-143
The Sapphire trial was organised as a randomised trial to compare carotid endarterectomy (CEA) with carotid angioplasty and stenting (CAS) using a protection device in so called high risk patients. The trial concluded that CEA and CAS were similar as far as stroke and death are concerned but CAS was superior when other complications were taken into account. The trial was flawed for several reasons. It was commercially funded and the inventor of the protection device was one of the investigators and therefore not in equipoise. The end points of the trial favoured CAS by making a biochemical myocardial event an end point. The surgeons doing CEA in the trial did relatively few CEA’S per year and had a high stroke and death rate. These surgeons also excluded over 400 patients from the trial because they were said to be too difficult or risky to operate on. The precise reasons for this exclusion have never been made clear except that the surgeons were probably inexperienced. Finally the patients were heterogeneous, more than 70% being asymptomatic or suffering from recurrent stenosis. For all of these reasons the Sapphire trial’s conclusions that CAS is equivalent to CEA in high risk patients cannot be scientifically justified. 相似文献
97.
目的 探讨颈部推拿手法对兔颈动脉粥样硬化(CAS)重度狭窄的血管拉伸力学特性的影响。 方法 45只新西兰兔随机分为颈椎旋转组(n=12)、推桥弓组(n=12)、模型对照组(n=12)和空白对照组(n=9),在颈椎旋转组、推桥弓组和模型对照组建立左侧CAS模型,并分别接受颈椎旋转手法、推桥弓手法干预3周,模型对照组和空白对照组不作手法干预。取左侧颈动脉进行单轴拉伸试验和病理观察,比较四组兔颈动脉的拉伸力学特性。 结果 (1)26只兔造模成功,其中颈椎旋转组、推桥弓组、模型对照组兔颈动脉的最大载荷显著高于空白对照组,同时最大应变显著低于空白对照组(P<0.05);(2)颈椎旋转组兔颈动脉的弹性模量显著高于模型对照组、推桥弓组和空白对照组(P<0.05),而推桥弓组兔颈动脉的弹性模量与模型对照组相比差异无统计学意义(P>0.05)。 结论 动脉粥样硬化病变可致兔颈动脉血管拉伸力学特性下降,而颈部旋转推拿治疗可导致严重粥样硬化病变并重度狭窄的兔颈动脉弹性下降,为临床安全应用颈部推拿手法提供了参考。 相似文献
98.
Jeong-Keun Yu Gyojun Hwang Seung Hun Sheen Yong-Jun Cho 《Journal of Korean Neurosurgical Society》2011,49(4):229-230
Visual loss is one of the ocular symptoms resulting from a carotid cavernous fistula (CCF), but has rarely been reported as the sole manifestation in CCF. Visual impairment is known to be associated with a poor outcome unless timely intervention is employed. Herein, the authors report a patient with bilateral rapid progressing visual loss as a sole manifestation in CCF. Vision was successfully restored by transarterial embolization. The authors discuss the necessity of urgent fistula obliteration in patients with visual loss. 相似文献
99.
《Annales de cardiologie et d'angeiologie》2017,66(5):275-282
BackgroundCarotid atherosclerosis is a powerful predictive factor of vascular risk at the individual patient level. Ultrasonography is a reference technique for the evaluation of this condition. However, its use in common practice remains difficult due to a lack of standardization and inter-operator variability. We present a new and simple technique for the assessment of carotid atherosclerosis; and evaluate the ability of vascular neurologists to obtain results consistent with those of an expert in vascular ultrasound.Material and methodsThe TIMMA scale is an acronym for the five classes of carotid atherosclerosis in French, VIMMA in English: very important, important, moderate, minimal and absent. Combined, the first two classes make up the group “significant atheroma” and the last three classes make up the group “no significant atheroma”. This scale was evaluated in 38 patients (76 carotid arteries) suffering from ischemic stroke or transient ischemic attack by five operators who are competent in carotid echocardiography: one TIMMA-trained (40 hours of training) vascular neurologist physician (VNP), three VNPs informed on the measurement method (1 hour of information) and one specialized vascular physician (SVP) who was considered to be the reference examiner. We evaluated the concordance between the VNPs and the SVP in classifying patients, firstly into the significant or not atheroma group and, secondly, into the five TIMMA classes.ResultsThe evaluation of the two-group clustering scale found a concordance between the informed VNPs and the SVP on 76 carotid arteries of 86% (kappa = 0.7) and between the trained VNP and the SVP on 58 carotid arteries of 90% (kappa = 0.8). The positive and negative predictive values for significant atheroma diagnosis were 100% and 81%, respectively, for the informed VNPs, and 100% and 80% for the trained VNP. The evaluation of the Five-Class Scale showed a concordance between the informed VNPs and the SVP of 46% (kappa = 0.3), and between the trained VNP and the SVP of 74% (kappa = 0.7).ConclusionTIMMA allows VNPs who are competent in carotid ultrasonography to reproducibly identify subjects with significant carotid atheroma. The contribution of this scale to the determination of cardiovascular risk should be evaluated. 相似文献
100.