魔魔兽战国td 怎么造:既安全又可靠的手术

既安全又可靠

Oct 18th 2011, 14:00 by The Economist online 

2011年10月18日   在线经济学家

GONE are the days when surgery meant cutting a patient open. Modern medicine offers doctors a panoply of less invasive tools to thrust inside disease-stricken bodies. One popular method is to insert long, thin, flexible tubes called catheters into the body and administer treatment through them. Patients tend to recover more quickly from such procedures than they would going under the knife. A drawback is that a catheter-toting surgeon only has a limited view of the afflicted region. Now, though, Philips, a Dutch engineering giant, may broaden that picture with the help of a tiny new scanner.

       手术意味着切开病人的皮肤，这种时代已经过去了。现代医学为医生们提供了，插入病体的全套工具，可以不用深入人体。很常用的一种方法，就是将一根薄而长的灵活的管子，即所谓的导管，插入人体进行治疗。经过这种治疗过程，病人会恢复的比挨刀的更快。遗憾的是，导管手术所能看到的病灶区域很有限。现在荷兰的工程巨头飞利浦，采用一种新的微型扫描仪，有望扩大成像范围。

One treatment commonly administered with a catheter is cardiac ablation therapy. It is used to treat some forms of irregular heartbeat, such as atrial fibrillation. It can be carried out under local anaesthetic and involves inserting a catheter into a blood vessel, guiding it into the heart and using high-frequency radio waves released from the probe’s tip to apply heat to the bit of tissue causing the problem. The resulting scar tissue blocks the abnormal flow of electrical signals that can cause irregular heartbeats.

       目前在心脏切除手术中，常采用这种导管治疗方法。用这种方法治疗不规则心脏搏动，如房颤。经过局部麻醉，将一根导管插入血管，再导入心脏，通过探头顶端发出的高频无线电波，给患病组织块加热。结疤的组织，会阻止引起不规则心脏搏动的异常电信号流。

The procedure has plenty to commend it. However, it takes four to six hours. And, crucially, one patient in three needs to have it repeated. That is because although assorted imaging devices, like live X-rays, can help put the catheter in the right place, they are unable accurately to measure how much scar tissue builds up when the heat from the catheter is applied. Too little, and the abnormal signals will not be blocked; too much, and serious damage could be caused to nearby organs.

       这种治疗方法还存在许多争议。然而，这种方法只历时四到六小时，而且关键是，三分之一的病人需要重复治疗。这是因为，尽管其他成像设备，如X射线成像，可以辅助将导管送达合适位置，但当导管送出热量后，却不能精确测量有多少结疤组织形成。如果太少，则无法阻止异常信号；太多，会对周边器官造成伤害。

To give surgeons a clearer picture of the scar tissue, the Philips researchers squeezed an ultrasound transducer down to just 1mm (0.04 inches) and inserted it into the tip of an ablation catheter. Ultrasound has, of course, long been used in medical imaging. It relies on the fact that sound travels faster through denser tissues. So, when a transducer—built using materials that vibrate when a current is passed through them—sends a sound wave through the body, the time it takes for the echoes to return to it can be used to construct a picture of different tissues and organs. 

       为了能给手术提供结疤组织的清晰图像，飞利浦的研究人员，将一个超声波传感器，缩小至1毫米（0.04英寸），插在用于切除手术的导管的顶端。超声波用于医学成像，已有很长一段历史了。其基础原理是，声波在越密的组织中，传导速度越快。因此，用一种有电流通过就会发生振动的材料，制成传感器，通过人体发送声波，通过测量回声返回需要的时间，可以构造出不同的组织和器官的图像。

The size of ultrasound scanners has been falling. Some machines, complete with the screens on which the images are shown, are now no bigger than a mobile phone. Probes are already applied from inside the body, too, like those inserted down the oesophagus to examine abnormal growths or to get a clearer image of the heart. But these probes are clunky and need a wide tract to move through.

       超声波扫描仪的体积，已逐步改小。现在一些带显示屏的仪器，还没有手机大。探头也可以不用插入体内，如可将探头插入食管，检查异常生长或得到心脏的清晰图像。但这些探头比较笨重，要有很宽的移动轨迹。

Philips’s device, by contrast, is small enough to squeeze through a blood vessel and examine the heart from the inside, something that has never been done before. The company will not disclose precisely how it managed to engineer an ultrasound transducer down to such a small scale, but fitting one into the tip of a catheter allows measurements to be taken accurately enough for surgeons to monitor the build up of scar tissue in real time.

       相比而言，飞利浦的设备，体积很小，可以放入血管内，从内部对心脏做检查，这是前所未有的。公司是不会确切披露，如何把超声波传感器设计得如此小，但在导管顶端安装一个这样的超声波传感器，可以在手术中得到精确的测量结果，以实时监控结疤组织的形成。

The experimental system, which is bound to have other uses in medical imaging (and possibly beyond), still has several years of clinical trials ahead of it. But if these go to plan, fewer procedures like cardiac ablation will need to be repeated, lowering the number of readmissions, and with it cost of treatment. Both patients and hospitals will certainly like the sound of that.

       这个实验系统，在医疗成像方面（可能超出此范围）还有更多用途，还需经过几年的临床试验。但一旦投入使用，像心脏切除术这类的手术，将不需要太多的重复过程，从而减少入院次数，降低治疗成本。肯定会受到病人和医院的欢迎的。