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1.
Laryngotracheal stenosis is defined as a congenital or acquired narrowing of the airway. Congenital causes may include subglottic membranous or cartilaginous narrowing. Acquired causes may include trauma due to prolonged endotracheal or tracheal intubation or laryngotracheal injury. Although advances have been made over the past 30 years in reconstructive surgeries to improve airway patency in these patients, long-term laryngeal function for voice production is not well defined in this population. This review examines causes, symptoms and signs, and methods for diagnosing laryngotracheal stenosis. Surgical management procedures are briefly summarized. The current literature on voice outcomes is summarized. The predominant voice characteristics in the population are presented, although results are challenged by the heterogeneity of voice presentation and paucity of data from instrumental measures. Considerations for subjective and instrumental assessment, measures of quality of life, instrumental methods, and treatment options specific to the needs of this population are discussed. Research strategies to identify long-term outcomes of surgical and behavioral treatments in this population are posed.  相似文献   
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本文对CT联合血清同型半胱氨酸(HCY)、β2-微球蛋白(β2-M)在下肢动脉狭窄闭塞性疾病中的诊断价值进行分析。选取上海市金山区中西医结合医院收治的120例疑似下肢动脉狭窄闭塞性疾病患者进行研究,选取同期健康体检者120例作为对照组,对患者进行CT检查、血清HCY和β2-M水平检查,并比较了CT诊断下肢动脉狭窄闭塞情况、两组患者血清HCY和β2-M水平,以明确CT、HCY、β2-M诊断价值及误诊率、漏诊率。结果显示,120例疑似患者中,CT检测出646节段病变血管,其中轻度狭窄155节段,中度狭窄257节段,重度狭窄143节段,血管完全闭塞91节段;研究组患者血清HCY、β2-M水平明显高于对照组,两组比较差异有统计学意义(P<0.05);HCY的AUC为0.863,截断值>21.75(μmol/L),诊断敏感性为79.00%,特异性为80.00%,β2-M的AUC为0.837,截断值>2.98(μmol/mL),诊断敏感性为75.25%,特异性为65.21%;CT诊断阳性率为67.50%,HCY诊断阳性率为69.17%,β2-M诊断阳性率为67.50%,三者联合诊断阳性率为82.50%,联合诊断阳性率高于CT、HCY、β2-M单独诊断阳性率(P<0.05);CT、HCY、β2-M单一检测对下肢动脉狭窄闭塞性疾病均有较高灵敏度、特异性及准确度,但三者联合诊断灵敏度、特异性及准确度最高,误诊率、漏诊率最低。本文证实了采用CT联合血清HCY、β2-M诊断下肢动脉狭窄闭塞性疾病诊断灵敏度、特异性及准确度高,误诊率、漏诊率低。  相似文献   
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选取我院60例腰椎管狭窄症(LSS)患者作为研究组,同期健康者60例作为对照组,探究CT检查参数对LSS的诊断价值及与疗效、腰椎功能改善的相关性。结果显示,研究组椎管面积、硬膜囊面积、椎管矢径、椎管横径、侧隐窝矢径、侧隐窝角小于对照组(P<0.05);CT各参数联合诊断LSS的AUC值大于任一参数单独诊断;疗效优良患者术后3个月椎管面积、硬膜囊面积、椎管矢径、侧隐窝矢径、侧隐窝角大于治疗前及非优良患者(P<0.05);经偏相关性分析发现,CT检查参数与疗效显著相关(P<0.05)。说明LSS疗效、腰椎功能改善情况与椎管面积、硬膜囊面积、椎管矢径等关系密切,CT检查对指导临床完善手术方案有重要意义。  相似文献   
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研究多层CT与DSA对急性冠状动脉综合征患者冠状动脉支架置入术后通畅性及狭窄程度的影响。以我院2017年8月-2018年11月在我院诊断治疗的急性冠脉综合征患者80例作为研究对象,对所有患者进行经皮冠状动脉介入治疗(percutaneous coronary intervention,PCI)手术后,分别进行DSA检查以及64排螺旋CT检查。分析不同检查的冠状动脉狭窄、通畅性之间的差异以及不同检查的一致性。通过对CT检查结果以及DSA检查结果的配对卡方检验,两组患者的检查结果之间的差异不存在统计学意义,两种检查对患者的冠状动脉的狭窄情况诊断一致性较好;两种检查方法对患者的管壁厚度以及管径直径诊断之间的差异不存在统计学意义,两种检验方法对患者的管壁厚度以及管径直径诊断一致性较好。总之,多层CT与DSA对急性冠状动脉综合征患者冠状动脉支架置入术后通畅性及狭窄程度的诊断具有较高的一致性,建议临床推广。  相似文献   
7.
与血管狭窄有关的异常血液动力学特征在血管疾病的发生和发展过程中起着重要的作用,由于血管狭窄和弯曲的综合影响,将会出现一系列有趣的流体力学现象,本文研究具有对称狭窄的弯曲小动脉内定常血液流动,在一定的假设条件下,直接从支配血液流动的Navier-Stokes方程求出问题的摄动解,由此求得弯曲狭窄管內血液流动的轴向速度、二次流速度及压力梯度等分析表达式,并进一步求得轴向和周向血管壁切应力。本文的结果是先前有关狭窄直管和弯曲均匀管流动研究的拓广。  相似文献   
8.
Dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) allows the noninvasive assessment of brain hemodynamics alterations by quantifying, via deconvolution, the cerebral blood flow (CBF) and mean transit time (MTT). Singular value decomposition (SVD) and block-circulant SVD (cSVD) are the most widely adopted deconvolution method, although they bear some limitations, including unphysiological oscillations in the residue function and bias in the presence of delay and dispersion between the tissue and the arterial input function. A nonlinear stochastic regularization (NSR) has been proposed, which performs better than SVD and cSVD on simulated data both in the presence and absence of dispersion. Moreover, NSR allows to quantify the dispersion level. Here, cSVD and NSR are compared for the first time on a group of nine patients with severe atherosclerotic unilateral stenosis of internal carotid artery before and after carotid stenting to investigate the effect of arterial dispersion. According to region of interest-based analysis, NSR characterizes the pathologic tissue more accurately than cSVD, thus improving the quality of the information provided to physicians for diagnosis. In fact, in 7 (78%) of the 9 subjects, CBF and MTT maps provided by NSR allow to correctly identify the pathologic hemisphere to the physician. Moreover, by emphasizing the difference between pathologic and healthy tissues, NSR may be successfully used to monitor the subject's recovery after the treatment and/or surgery. NSR also generates dispersion level and non-dispersed CBF and MTT maps. The dispersion level provides information on CBF and MTT estimates reliability and may also be used as a clinical indicator of pathological tissue state complementary to CBF and MTT, thus increasing the clinical information provided by DSC-MRI analysis.  相似文献   
9.
We present an efficient implementation of the proper (in vivo) outlet boundary conditions in detailed, three‐dimensional (3D) and time‐periodic simulations of blood flow through arteries. This is achieved through the intermediate use of an approximate ‘simulant’ model of the outlet pressure/flow relationship corresponding to the full 3D and time‐dependent numerical simulation. This model allows us to efficiently couple the 3D outlet pressure/flow conditions to the equivalent relations due to the downstream arterial network, as obtained from a one‐dimensional approximate model in the form of Fourier frequency impedance coefficients. An adjustable time‐periodic function correction term in the simulant model requires input from the full 3D model that has to run iteratively until convergence. The advantage of the proposed numerical scheme is that it decouples the upstream detailed simulation from the downstream approximate network model offering exceptional versatility. This approach is demonstrated here in a series of detailed 3D simulations of blood flow, performed using the commercial software FLUENT?, through an asymmetric arterial bifurcation. Two cases are considered: first a healthy system patterned after the left main coronary arterial bifurcation, and second a diseased case where an occlusion has developed in one of the daughter vessels, resulting in strengthening the asymmetry of the bifurcation. Rapid convergence of the iterative process was achieved in both cases. Subtle changes occur in the shear patterns of the daughter vessels, whereas the flow distribution is quite different. In the presence of a stenosis additional regions of low shear develop due to inertial effects. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
10.
目的研究在颈动脉狭窄检查中采取磁共振血管成像的诊断价值。方法回顾性分析惠州市中心人民医院自2015年12月至2016年12月期间收治的39例颈动脉狭窄患者所有资料,将减影血管造影检查结果作为金标准实行磁共振血管成像检查,分析狭窄检测敏感性、准确性以及特异性。结果磁共振血管成像检查狭窄检测敏感性、准确性以及特异性发生率分别为97.43%、92.31%、94.87%。结论将磁共振血管成像应用在检查颈动脉狭窄中具有显著效果,可以提升准确符合率,值得广泛应用与研究。  相似文献   
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