When Crazy Ideas Come into Reality
"The future exists today. " -William Gibson
A good depiction of Dr.Mark's fancies and crazy ideas about the development in R&D for medical apparatus which will come into reality soon.
就像馬克醫官之前提過的--不用扎針(one touch)就能知道血糖值的儀器(就像套在手指就能知道血氧飽和濃度) ，這期的Economists也提到可望取代傳統心電圖的舒適、輕便新發明。
做過心電圖electrocardiograph (ECG) 的人都知道, 拆下身上稠黏的電極時，似乎全身毛髮也會跟著被拔掉的那種折磨。這是因為電極偵測的電流相當微弱，要能有效感應，就必須盡可能縮短和皮膚的距離。
英國蘇克塞斯大學的Robert Prance以及同事們正著手使傳統心電圖走入歷史。他們開發了可能替代ECG 的一種設備-- electroencephalograph，藉由電阻感應器以及探針，以及末梢接收電子信號，並轉譯成心跳或腦波的判讀程式的結合，將可望取代不舒適的傳統電流檢測，不須與皮膚直接接觸，仍能達到相同的檢測效果。
ＰＳ～～Hey! You truly can look into the future! Dr. Mark!
Hearts and minds
May 29th 2007
From Economist.com
A device that detects heartbeats and brain activity at a distance
AS ANYONE who has undergone an electrocardiograph (ECG) examination knows, it is an uncomfortable procedure that involves sticky electrodes which seem to want to rip your body hair away when they are removed. This is because the current the electrodes detect is weak and a really good contact needs to be made between apparatus and skin.
Robert Prance and his colleagues at the University of Sussex, in England, plan to do away with all that. They have developed a device that can act as an ECG, or its cranial equivalent, an electroencephalograph, without even touching the skin. It does so by measuring the signal without drawing current, using high-impedance sensors.
Impedance is related to resistance—which, as generations of school children have had drummed into them, is the ratio of voltage to current. If current and voltage are fluctuating, however, other factors come into play as they interact with each other. Impedance is a measure of electrical resistance that captures the effects of this feedback.
The advantage of using high-impedance sensors is that the signal—an electric potential—can be measured at a distance. This is because the resistance is so great that a layer of air makes no appreciable difference. Indeed, Dr Prance’s device can pick up the trace of a heartbeat from a metre away. It can also sense electrical activity in the brain through the hair, and detect signals that correspond to eyeball movements.
The result is a probe that can easily be picked up by medics and held close to the patient. Wires attached to the back of the probe lead to a computer that translates the electrical signals into a picture of the heartbeat or brainwave. A test version developed by the team was the size of a watch and worn on the wrist. The production version will be of a similar size but will not touch the skin.
Indeed, Dr Prance hopes that his invention will not merely be more comfortable than today’s detectors, but better. He and his team are experimenting with joining many sensors together to produce pictures of electrical activity in the heart. An electrical wave traverses the heart each time it beats, co-ordinating the contraction and relaxation of the chambers that pump blood around the body. By joining 25 sensors together, the researchers hope to demonstrate the technique’s potential as a medical-imaging tool. It would be difficult to do this trick with conventional detectors.
Nor is the technique restricted to medical applications. It is already being adapted to look for faults in microelectronic circuits, and it might eventually be used to test mechanical components made of stainless steel or carbon fibre for structural integrity. It could thus be used to give machines, as well as people, a clean bill of health.
