MRI is a large-scale medical imaging device. The amount of information provided by this device is not only greater than other imaging techniques in medical imaging, but also very different from existing imaging techniques. Therefore, it has a great advantage in diagnosing clinical diseases. In order to reduce the failure rate of MRI and improve the efficiency of use, it is of great significance to carry out active and effective maintenance and maintenance work in normal times.
1. Network failure
MRI often freezes when using the machine. If it prompts a network conflict, check whether the IP address of the network host and the network in the hospital conflict. Usually, after changing the host address, this type of fault problem will be eliminated.
2. Bed in and out failure
If there is a loud noise when the bed is in and out, observe whether the bed height is normal. You can use manual or mechanical methods to adjust the bed height. It will be normal after returning to the upper stop position. If the bed cannot be in and out, the horizontal movement belt of the bed may be broken or fall off. It is usually normal after replacement.
If the head cannot be scanned and the image signal-to-noise ratio is poor, but the scan results of the patient's lumbar spine and knee joints are normal, the head coil should be replaced. If the image cannot be displayed during the scan, an IMAGE failure occurs, and it still cannot be restored after restarting, the IMAUE system needs to be reinstalled to restore the display image of the machine.
3. Failure of the water-cooled unit
The first is the addition of freon to the compressor in the water-cooled unit. When the spring and summer seasons alternate, the temperature will gradually rise. When the water temperature is higher than 20°, the freon pressure in the compressor can be checked. If the water temperature is high after adding freon, it is generally because the water volume of the water circulation is not reached. At this time, the water circulation part should be checked again, and it can be judged whether the filter of the water circulation is blocked.
Usually, after the filter is removed and cleaned, it can be used normally. The other is the failure of the high-pressure protection switch in the compressor. If the unit is reported for repair, it should be restarted. At this time, the high-pressure part of the compressor will keep rushing upwards. When it encounters pressure, the protection switch will be disconnected. Usually, this situation is caused by the failure of the fan in the high-pressure part of the compressor to work. Since the circuit in the fan is controlled by the high-pressure controller of the compressor, the two ends of the controller can be short-circuited at this time, and the machine can be used normally. After replacing the controller, this type of fault can be solved.
4. Strengthen the maintenance and maintenance measures of MRI equipment
Implement the "three-fixed" system management, and repair the faults in time
Implement the "three-fixed" management system, mainly for MRI equipment and equipment to implement the management system of fixed machines, fixed personnel and fixed positions; nuclear magnetic resonance imaging equipment requires special operators, who can only operate related equipment after strict training and examinations and obtaining the "operation certificate"; if it is newly purchased or overhauled equipment, it must be tested during the normal running-in period. Only in this way can the service life of the equipment be effectively extended; in addition, the safety disclosure system must be strictly implemented to ensure the safety and service life of MRI equipment.
5. Pay attention to the maintenance and care of the machine room
The power consumption of the MRI system should be guaranteed by a dedicated transformer, and a voltage-stabilized power supply and an uninterruptible power supply should be configured. The working conditions and alarm devices of various indicator lights for power distribution should be closely observed. Dust prevention and purification are the key to ensuring the best heat dissipation effect of the machine.
Therefore, cleaning agents should be used regularly to clean the dust accumulated on the surface of the circuit board due to electrostatic induction, and the cooling fan should be checked regularly to see if it is operating normally. The air filter should also be cleaned regularly to ensure that the heat generated in the cabinet can be discharged in a timely and smooth manner. When repairing the magnetic resonance, maintenance personnel should use the correct method, because if the detection method is used improperly, it will damage the circuit or detection instrument that is operating normally, so that the detection results cannot be kept accurate.
Finally, maintenance personnel are also required to check whether there is a loosening phenomenon caused by the interface of the circuit board due to different temperatures or long-term shutdown, and check whether the high-current connectors used in the power box of the spectrometer, gradient and radio frequency parts are loose.
6. Ensure the stability of the MRI operating environment
The image quality displayed by the MRI equipment is closely related to the surrounding environment. After the installation and commissioning of the equipment, any changes in the close range of the magnet (within 15 meters) will more or less affect the uniformity of the magnetic field, thereby reducing the quality of the image.
Therefore, it should be avoided as much as possible to add large buildings, parking lots, large equipment and other ferromagnetic objects or environments around the nuclear magnetic machine room after the installation and commissioning. It is also necessary to avoid adding high-frequency transformers, transmission lines and other equipment that can generate high-power electromagnetic radiation to affect the MRI equipment.
7. Optimization of MRI use and maintenance
In order to further improve the management level of nuclear magnetic resonance imaging equipment, improve the working efficiency of MRI equipment, and reduce the cost of equipment maintenance as much as possible, it is necessary to strengthen the use and maintenance and information feedback between maintenance personnel, and then incorporate the maintenance of nuclear magnetic resonance imaging equipment into the preventive maintenance system. Therefore, it is necessary to cultivate maintenance personnel with the ability to independently complete emergency repair tasks and take emergency repairs, strive to achieve "one specialty and multiple skills" talents, strengthen the operation of MRI equipment and the management of maintenance personnel, so as to achieve good equipment management results.
Whether it is preventive maintenance or troubleshooting maintenance, the use status of the MRI equipment should be diagnosed quickly and accurately first. However, due to the limited practical experience and technical quality of maintenance personnel, they often make inaccurate judgments, resulting in incorrect disassembly and installation of components or assemblies, which may lead to premature replacement of some parts, resulting in unnecessary economic losses and affecting the use of the equipment.
