Hand Held Metal Detectors!!NOT FOR USE IN MRI ROOM!!
Hand held metal detectors incorporate the benefits of magnetometers and metal detectors, allowing a rapid analysis of the patient in the search for any ferromagnetic metal objects.
Magnetic Resonance Imaging (MRI) generates a strong magnetic field, at present in the order of 3-4 T (Tesla), far in excess of the earth’s magnetic field, which reaches a maximum of about 70 µT at the poles. This strong field can cause serious damage to patients that have ferromagnetic metal devices or implants. The damage is proportional to the field generated, the mass of the object and its degree of magnetic susceptibility.
Why Hand Held Metal Detectors are used:
The potential problems that can arise are dislocation or torsion, overheating or induction of electrical current. It has been demonstrated that the latter two effects, due to the high-frequency component of the electromagnetic field, are negligible. On the other hand, the static magnetic field generates a force on ferromagnetic materials: if these objects are present inside the human body they can damage the surrounding tissue, while in the case of objects inadvertently carried in the within the area subjected to the magnetic field, they can be violently attracted towards the magnet with a bullet type effect. Many studies have been carried out to establish whether certain devices, prostheses or implants commonly used in medicine are dangerous during MRI scans. The results show that the majority of the devices or metal parts inside the human body are not dangerous during this type of analysis, but that a small percentage of them are. Most of the devices or implants are made of non-ferromagnetic materials (e.g. titanium, titanium alloys, stainless steel, tantalum or ceramics), and so are not influenced by the static field. Examples of such devices are some haemostatic clips, dental implants (except the wires of the braces) and orthopaedic implants. Some devices are made of materials which are slightly ferromagnetic (e.g. stainless steel, chromium alloys), which are attracted by the magnetostatic field in proportion to its intensity. Examples of these devices are cardiac valves and the wiring of dental braces. In both cases the force of attraction is less than that exerted by the binding of the device to the human body, and so the risk of damage is low. Other devices, such as some haemostatic clips or contraceptive diaphragms, are ferromagnetic, and so their use during MRI scans is advised against. Despite the existence of problems linked to the use of MRI, adequate pre-MRI scanning procedures are not that widespread. Generally the patient is presented with a questionnaire regarding any surgical operations or accidents at work that might then indicate the presence of metal objects inside the body. Very often, however, patients might not be aware of the type of metal inside their bodies, or might not interpret the questions correctly. Direct analysis procedures such as radiography is invasive and costly. The use of magnetometers and metal detectors is often overlooked or omitted. A pre-MRI inspection could help the doctor in assessing the risks and preventing accidents. Detractors of the use of magnetometers and metal detectors complain about the low sensitivity of the former and the ineffectiveness of the latter due to the lack of discrimination between ferromagnetic and non-ferromagnetic metals
**2 Year Warranty on Product**