Medical patients are screened prior to magnetic resonance imaging by using a superconducting quantum interference device magnetometer to detect the unknown presence of an implanted ferromagnetic object. The patient is placed on a table which vibrates at approximately five Hertz. The magnetometer is sequentially...http://www.google.com.au/patents/US5494035?utm_source=gb-gplus-sharePatent US5494035 - Method for detecting presence of ferromagnetic objects in a medical patient
