It is currently difficult to imagine practical medicine without equipment such as MRI. Which device is better to use in certain clinical cases? This question is often asked by medical workers, since the range of products offered on the modern market is quite wide. Undoubtedly, MRI is superior to X-ray and CT due to the absence of gamma radiation. More details about the advantages and disadvantages of MRI, as well as the correct selection of the best equipment, will be discussed in this article.
The structure and types of tomography
Which device is best for MRI? To answer this question, we will consider the structure of the tomograph and get acquainted with different types of equipment for tomography. The design of all devices is the same and includes:
- sensors for transmitting, receiving, and processing data;
- magnet;
- shielding systems;
- different coil frequencies;
- cooling system.
All types of equipment are divided into:
- Closed - they are a ring-type horizontal pipe open at both ends.
- Open - in this case, the device is not closed on the sides. It is mainly used for small patients and adult individuals with fear or fear of an enclosed space.
According to the source of the magnetic field, the equipment is divided into:
- constant;
- resistive;
- superconducting;
- hybrid.
It is important to remember that each tomograph is endowed with specific characteristics, pluses and minuses. Only an experienced and highly qualified specialist is able to make the right choice and decide which MRI device is best for examining an organ.
Power Classification
Based on the tension between magnetic fields, medical tomographs are divided into the following types:
- Ultra high floor - can only be found in specialized research laboratories, since such an apparatus has a high level of power.
- High floor.
- Srednepolny - most often found in health facilities.
- Low-floor - is present in medical organizations in which there is insufficient financial resources. The result of research on such equipment is very average. The reason lies in the low signal-to-noise ratio; as a result, the process of examining and obtaining data is quite lengthy. However, there is an advantage, such devices have a small number of contraindications for use.
- Ultra low.
The principle of MRI
In any cell of the body there is a hydrogen molecule having a positively charged particle. When an electromagnetic field influences a part of the body, the particle begins to move. When the action ceases, it stops moving, calms down and releases energy, which the tomograph registers, i.e., this method is based on observation of hydrogen atoms.
Thus, it is possible to consider internal organs, the brain and spinal cord, as well as conduct other studies on how energy is released.
Which MRI is better? It is not easy to answer this question, since all devices of the new generation have safety and high information content, and are also able to solve various diagnostic problems. Some prefer Siemens brand equipment, while others prefer Philips. Only specialists will recommend a specific device depending on the indications, the weight of the individual, etc.
Advantages of MRI
The most important advantage of the equipment is the high accuracy of the results. Some types of devices allow you to examine every two centimeters of the body of an individual and consider almost any pathology. With the help of MRI, even a neoplasm that is located under the bone tissue can be detected, and its detection is not possible by other methods, for example, radiography or ultrasound.
Another important advantage is the three-dimensional image that is displayed on the monitors. As a result, the doctor has the opportunity to examine the desired site from all sides. In addition, this procedure is completely harmless, since the patient is not exposed to radiation exposure.
Disadvantages of MRI
In some people, being in a closed capsule causes a feeling of fear, panic, and suffocation. If the manipulation takes a long period, then the patient may have arrhythmias and respiratory movements that can distort the result. The disadvantages include the high cost of the examination.
The disadvantages of open type apparatus include the duration of the manipulation, while the results, in particular their detail, are inferior in quality to the closed type of apparatus.
Contraindications for MRI examination
As with other methods, the described one has contraindications. Fortunately, there are few of them. This type of study is not recommended in the following situations:
- if the individual has a pacemaker or a metal implant;
- staples and clamps on the vessels;
- in the first three months of pregnancy;
- mental pathologies.
With caution, this procedure is performed for patients with cardiac pathologies, for example, heart failure.
Which MRI device is better - open or closed?
There is no single answer to this question. For example, the first resonance tomographs, which are often present in our hospitals, have sufficient power and I use them for various examinations. Their disadvantage is the small diameter of the annular part - about 70 cm. Thus, it is not suitable for persons who are overweight. For them, it is best to use an open type apparatus. The advantage of these MRIs is that they are suitable:
- for patients with mental disorders;
- examination of one part of the body or organ;
- for overweight people;
- children.
An open type apparatus allows a physician to talk with a patient. Its design makes it possible to adopt a comfortable pose for a person.
Thus, in order to determine which MRI device is better, it is necessary to study its technical functionality and power. The quality of the resulting images depends on this indicator. For example, for childcare, the best option would be an open type.
When choosing equipment, it is very important not to make a mistake, since the lives of patients will depend on the results of the diagnosis.
Brain examination
To determine which device for brain MRI is better, you need to study its technical characteristics.
The image quality and shooting speed depends on the voltage, i.e. the higher it is, the more high-quality result will be and the smaller the distance between the slices. For high-floor devices, it is less than two, and for low-floor devices - six millimeters. Thus, a high-field tomograph will best cope with the detection of the smallest defects in the blood supply to the brain.
MRI of the spine: which device is better?
This type of examination is of great diagnostic value. In this case, the following departments are subject to research:
- thoracic;
- lumbosacral;
- cervical;
- sacrococcygeal.
The examination is usually carried out on standard tunnel-shaped tomographs. The exception is the large weight of the patient, i.e. over 130 kilograms. In this case, the doctor will advise an open type apparatus. Its disadvantage is less power compared to closed. However, when it is not possible to conduct a study in another way, such results are considered useful for the doctor. Which MRI is better? The answer to this question depends on the specific situation and the individual characteristics of the subject.
Conclusion
MRI is called a unique diagnostic method in which the patient’s body is not exposed to stress and danger. In exceptional cases, such an examination is carried out under general anesthesia, and in some situations a contrast agent is required. The only inconvenience a patient may experience is being in a narrow capsule for some time.
High-field tomographs are considered the gold standard in the field of magnetic resonance imaging and are recognized as the most informative. They provide the opportunity to get clear pictures. And thanks to the powerful magnetic effect that this device has, it is possible to detect even tiny pathological foci that are in the patient's body.
Therefore, when asked about which MRI device is the best, most experts will answer that it is a Siemens high-field tomograph with a capacity of 1.5 TL.