外周动脉狭窄的频谱特征崔斌辽源.pptVIP

外周动脉狭窄的频谱特征 吉林省辽源市中医院 崔斌 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 一、狭窄处血流速度增高；估测标准是狭窄处血流速度与相邻近侧正常动脉段速度之比大于2，狭窄＞５０％，大于４，狭窄＞７５％ 但是当狭窄率大于８０％时，狭窄处流速可能下降。 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 二、狭窄即后段湍流：此区域血流紊乱或湍流，出现湍流是诊断动脉狭窄的重要依据，是诊断动脉重度狭窄的必须依据。 紊乱血流以狭窄以远1cm之内最显著，以远2cm处，湍流血流降低，3cm处血流恢复相对层流。 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 三、狭窄前动脉搏动性增强：此种情况指的是在没有形成侧支循环的前提之下 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 狭窄远段动脉搏动性减弱：严重狭窄导致血流量降低，远端血流信号减弱，脉冲多普勒显示狭窄远段频谱波形低钝，流速降低，收缩峰上升缓慢，阻力指数降低，呈“小慢波”。 注意如果低速，低阻波形发生于双侧，病因可能来源于心脏，如主动脉瓣高度狭窄或心力衰竭等。 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 病例 患者男56岁，头晕，右侧无脉，血压比左侧低100mmhg 分析:从临床症状可以判断，动脉狭窄位于肱动脉近心段，常见病变位于右锁骨下动脉起始处及头臂干 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. RSCA Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. RCCA Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. RICA Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 右颈总动脉收缩期流速减低，加速度时间延长，RI值减低，说明在右颈总近心段出现狭窄，而最易出现狭窄的部位，在头臂干与右颈总动脉分叉处，据此向下探查 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 头臂干出现五彩血流信号，流速4m/s，说明狭窄率75% Evaluation only. Created wit