An interrogation device is used to locate a nerve within the body. The device uses a piezoelectric crystal to locate a pulsing vessel proximate with the nerve. As the device is guided toward the nerve, it can emit an electric signal to stimulate the nerve. The operator can then watch for any physical...http://www.google.es/patents/US5779642?utm_source=gb-gplus-sharePatente US5779642 - Interrogation device and method
