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Magnetic resonance imaging of the thyroid gland refers to the methods of radiation exposure. It is able to provide in a short time the most detailed results on the state of health of the organ responsible for the production of vital hormones.
In addition to the ability to obtain a standard three-dimensional model of the specified area with good contrast, the doctor will receive a layered image of the thyroid gland. All this together makes it possible to diagnose deviations in the structure of the gland, up to the detection of neoplasms of various etiologies.
Advantages and disadvantages
Unlike many other techniques, MRI of the thyroid gland sometimes makes it possible to detect the slightest abnormal changes, up to tiny tumors. With the help of high-precision imaging, it will be possible to determine the presence of a capsule, as well as to clarify whether there is any spread to other structures. The latter is especially true if the patient has suspicions about possible malignant tumors.
Very often, when examining the thyroid gland, an additional study with contrast is required to more accurately confirm the diagnosis. Despite the fact that the price of manipulation, taking into account the additional stage of contrasting, will be higher, the result will provide an opportunity for a detailed verification of the diagnosis by establishing the degree of damage, the territory covered by the pathological process, as well as the possible impact on neighboring structures.
If we talk about the advantages of the technique over an x-ray, then the relative novelty in the world of medical technology wins significantly in several ways. In addition to the ability to cover the bone structure of the area under study, MRI allows you to visualize muscles and lymph nodes, which are not always possible to thoroughly examine even with ultrasound technology.
Pleases patients who are to undergo this examination, and the fact that there is no radiation exposure. Instead of conventional radiation exposure, the technology is based on the features of the magnetic field, which was the reason for the name of the method.
The most important advantage is that the thyroid gland itself is not affected during the scan. It concerns the counterbalance in favor of the magnetic resonance tomography in relation to the classical computed tomography.
The latter often requires the use of a contrast agent. It includes iodine-containing components, which, in some ailments of the gland, in themselves pose a serious threat.
For the magnetic analogue, substances of a different type are involved, which do not cause any damage to the thyroid gland, which explains the popularity of the technique. This fact becomes, as a rule, also a significant argument in favor of MRI, despite the fact that usually the examination lasts longer than CT.
The method has another advantage, namely, when it comes to the inability to recognize with a XNUMX% guarantee – a benign or malignant tumor was found in the patient – by connecting the stage of contrasting for clarification, the percentage of error rapidly moves to zero. Moreover, an experienced doctor never makes a verdict on the nature of the tumor only on the basis of examination data. He will certainly take into account the patient’s complaints, his hereditary predisposition, the results of other tests, including a test with oncological markers, and most importantly, histological analysis data.
When is an MRI necessary?
The endocrine system is responsible for the production of hormones, interruptions in the supply of which cause obesity, dry skin and other external manifestations, as well as problems of internal organs.
All this can be prevented if the disease is detected at the beginning of its development. Often, what magnetic resonance imaging shows is related to the following anomalies:
- tumors of various origins;
- autoimmune thyroiditis;
- infectious inflammation;
- nodes;
- foreign bodies;
- mediastinal tumors.
But all of the above is not a definitively complete list of diagnoses that are revealed using the results of the examination. In order to send his ward to the diagnostic room, the doctor must have substantial grounds for this. Among them, the following complaints and concomitant symptoms in the victim are distinguished:
- nodular goiter that grows in the sternum;
- gland hyperplasia;
- sudden weight gain or loss;
- problems with sleep;
- increased fatigue;
- heart failures.
If the patient cannot undergo a scintigraphy due to the use of thyreostatic drugs, then he will be offered an MRI as a worthy alternative.
Despite the fact that the MRI result can provide quite extensive information about the internal state of the thyroid gland and the surrounding space, an experienced doctor can send the ward for auxiliary tests at his own discretion, such as ultrasound, CT and various tests to determine the functionality of the thyroid gland.
Serious and not so contraindications
Many women are interested in the question of what will happen if an MRI is done during pregnancy. But it is this condition that is considered a relative contraindication in the first trimester, since an examination involving a magnetic field may not benefit the baby. Especially in situations with mandatory use of contrast.
To eliminate the risks of harming the fetus in the form of inhibition of its mental or physical development, it is worth notifying the attending specialist about pregnancy in advance, and he will send the expectant mother to be examined using a more gentle ultrasound examination.
But the period of breastfeeding is not a serious prohibition, except in cases where the use of a contrast agent is necessary. Just in this case, it is necessary to refuse lactation for a period of at least two days after the introduction of contrast. During this time, potentially dangerous milk is expressed and discarded.
The most important problem for using a magnetic tomograph is the presence of built-in electronic mechanisms or metal elements in the body. The former include pacemakers, built-in hearing prostheses, and similar assistants that improve the quality of life. If a person has something similar in any part of the body, then the procedure is abandoned in favor of a safer analogue.
But the presence of knitting needles, pins and other metal components is not always considered a sharp contraindication. Here everything is decided by the attending physician, depending on the location of these structures and their composition, as well as the preponderance of the benefits of the analysis. Other relative prohibitions include:
- severe general condition;
- childhood;
- mental disorders.
The points listed above are dangerous due to the fact that people at risk are not able to maintain absolute immobility for a long period. After all, it is precisely thanks to the preservation of one pose for a long time that high-quality “images” can be obtained. Any careless movement will blur the whole picture, which will become the basis for redoing the analysis.
A dozen years ago, the fear of closed space was also included in the list of those contraindications that could not be overcome. To help such patients, only sedative medications were used. Today, technological progress has moved much further, offering open-type equipment to medical centers. That is, the tomograph has open side panels, retaining its own functionality, albeit at a lower level.
Preparation and procedure
Particular attention should be paid to the preparatory stage for people with obesity. The problem is that most of the new models are designed for a load capacity of no more than 120 kilograms. There are versions with an upper limit of 200 kilograms, but you need to look for them by calling the clinics yourself.
Most experts agree that it is better to wipe off all decorative cosmetics for the duration of the procedure. The increased severity is explained by the fact that sometimes decorative products contain traces of metals. Although they have little effect on image stability, when looking for tiny lymph node tumors, it is best to rule out any risks.
The most important point of preparation should be laying out all things with metal components. If you use the service of a private hospital, before the procedure, the patient will be given a special cotton hospital pajamas. It is fastened with plastic buttons or strings, which eliminates the risk of possible image distortion due to exposure to metal parts. If the hospital is not able to provide such a high service, then it is simply worth buying a disposable gown in advance.
Usually, there is no need to follow a specific diet or interrupt a previously approved medication course. But since there is a percentage of risks of confrontation between the components of the contrast agent and the medicinal composition, it is better to ask the doctor in advance to evaluate the compatibility of the elements.
The basis for the solution is the metal gadolinium. Usually it does not cause a sharp allergic reaction, but since there are no rules without exceptions, it is better to additionally conduct an allergic test. It will not take much time, and based on the data obtained, it will be possible to choose the best tool from the most common solutions:
- Magnevist;
- A bastard;
- Omniscan;
- Dotarem.
The difference between MRI options with and without contrast is not particularly large. In the first variant, the X-ray laboratory assistant, after conducting a native study, rolls the patient out of the apparatus tunnel, injects the substance intravenously using a catheter into the cubital vein, and rolls it up again.
After the patient is comfortably positioned on the table, his head is fixed with auxiliary straps so that in case of unforeseen circumstances the patient does not accidentally twitch. Such “unforeseen” circumstances can be sharp sound effects coming from a tomograph, and frightening young children.
After sending the table to the tomograph tunnel, the sensors read and transmit the information to the computer, where it is processed and a series of images is obtained from different angles to obtain the clearest possible projection.
The received data can be asked to be recorded on a digital medium. Then it remains only to decipher the results, which is the prerogative of the radiologist. The results come to him either through the patient himself, or sent by the diagnostic laboratory.