MRI of the temporomandibular joint

MRI of the temporomandibular joint is a promising method for diagnosing disorders of motor function of cranial bones. It allows to quickly assess the anatomical features and possible damage to the bones of the joint, its innervation, and the state of facial musculature without disturbing the integrity of soft tissues, providing the doctor with important information for making an accurate diagnosis.

Indications for the procedure

As we know from human anatomy, the lower jaw is the only mobile bone in the facial skeleton that allows us to take in and grind food to meet the body's nutrient needs. The mobility of the lower jaw is a credit to the temporomandibular joint, which is considered one of the most complex in the entire skeleton.

This joint is a paired joint, and the movement of both of its joints must be synchronized and coordinated. This is not a simple movement, but a combined movement that combines the sliding of the joint surfaces and their rotation around a floating center.

Sometimes, due to various reasons, the coherent work of the joint is disturbed, and to identify the cause of violations, doctors prescribe MRI of the temporomandibular joint as one of the most informative methods.

Such an examination is appointed during a doctor's appointment, where the patient may come with various complaints. Indications for MRI will be the following of them:

• unpleasant and painful sensations in the temples, cheek area, severe headaches,
• muscle tension in the lower jaw and cheekbones, neck, head,
• impaired sensitivity of the skin in the area of the joint,
• The appearance of a clicking sound (crunch) when moving the jaw,
• limited movement of the lower jaw, inability to open the mouth normally, speech and bite disorders,
• Involuntary fixation of the jaw in one position, inability to move it, open or close the mouth,
• difficulty chewing, discomfort during eating,
• rapid fatigue of the facial musculature,
• facial asymmetry,
• tooth soreness after sleeping,
• pain that radiates through the jaw, neck and into the shoulder,
• Facial edema not related to sleep deprivation, heart or kidney disease, unilateral facial edema.

It is understood that an MRI may be ordered if a dislocation or fracture of the jaw near the joint is suspected. The study is necessary for both diagnosis and the development of a treatment regimen.

MRI diagnosis is prescribed in case of suspicion of inflammatory processes in the joint (arthritis), rupture or perforation of the articular disc, osteoarthritis, osteomyelitis, synovitis, tumor processes in hard and soft tissues near the joint.

MRI of the temporomandibular joint is a preliminary (diagnostic) stage of orthodontic treatment and dental prosthetics.

Since MRI allows you to see details that are inaccessible to other diagnostic methods (radiographs, orthopantograms, computer scans), it is prescribed when the conducted examination cannot detect the cause of clinical symptoms. [1]

Preparation

Magnetic resonance imaging is a generally safe method of diagnosis, which allows you to get a lot of information about the internal structures of the skull skeleton without harming the patient's health. Such an examination does not require special preparation and can be performed immediately after arrival at the medical center.

Since MRI of the temporomandibular joint is prescribed by a doctor, the consultation with a specialist can be considered as preparation for the procedure. The doctor explains to the patient how safe the examination is, how it is performed, what should not be taken into the machine, how to behave during the operation of the equipment so that the images are reliable and of high quality, what contraindications to MRI are.

If this information is not given by the hospital doctor, the patient will learn all the information from the staff at the center who will perform the procedure.

If a person has a fear of enclosed spaces, they will be recommended options to help them calm down and endure the procedure to the end. This may include taking sedatives or listening to music, for which special equipment is provided. In case of severe pain, anesthetic medications will be administered.

There are no restrictions on diet, water or medications. If the study is planned to be performed with contrast, which is rare, the patient will be told in advance how to prepare for it.

Technique MRI of the temporomandibular joint

The procedure of MRI of the temporomandibular joint is extremely simple. The patient is asked to remove his or her outer clothing. You can take care of comfortable clothes in advance or use the clothes offered at the center. If you stay in your clothes, you will have to remove everything that contains metal parts (belts, buttons, buttons, cufflinks, dentures, etc.). Along with your outer clothing, you will have to leave all items that can interact with the magnetic field: watches, cell phones, keys, payment cards, metal jewelry, etc.

In the room where the MRI equipment stands, the patient lies down with his or her back on a movable table, which will later move in a magnetic loop. At this time, the machine produces several series of images. The patient's head is fixed with rollers, because immobility is the main condition for obtaining clear images, and not everyone is able to lie still for 5-15 minutes.

During the procedure, the patient is able to communicate with the physician who is in the next room. Two-way communication allows the patient to report discomfort and hear the doctor's instructions (e.g., if necessary, to hold their breath) when in different rooms.

If the patient complains of restricted mobility of the lower jaw, up to its jamming, MRI of the left and right temporomandibular joint is performed, for which separate radiofrequency coils of rounded shape are applied to them. Since the joint is paired, it is necessary to examine both parts, otherwise it is difficult to determine which side of the problem lies, if the patient himself can not specify the localization of unpleasant sensations.

If clinical symptoms related to jaw movement (during chewing, speaking, opening the mouth, etc.) appear, an MRI of the temporomandibular joint with functional tests is prescribed. The biphasic study includes scanning with the mouth open and closed. Open-mouth scanning is performed for 5 minutes; to facilitate jaw fixation, the patient is offered to clamp an object (most often a tube of toothpaste) between the teeth.

What does MRI of the mandibular joint show? On the images obtained with the help of magnetic resonance tomography you can see microscopic structures with the possibility of their examination in different projections, assess the state of the mobile bone, articular disc, facial muscles and ligaments.

A tomogram makes it possible to examine various anatomical structures and changes in them, detect foreign inclusions, tumor processes, congenital defects of the jaw and joint, traumatic disorders. The doctor is able to assess the state of the vessels of the area under study, differentiate functional disorders and degenerative processes, identify bite disorders and the causes that cause them. [2]

Contraindications to the procedure

MRI is considered one of the safest diagnostic methods, so it does not have a large list of contraindications that many other methods of body research have. Even existing contraindications are only related to the possibility of interaction between the magnetic field and ferromagnetics used in the manufacture of various devices. This interaction can damage the device and introduce distortion in the images obtained by the tonometer.

There are very few absolute contraindications to MRI of the temporomandibular joint. This includes situations when a person, for medical reasons or other reasons, cannot part with the device or metal objects in his or her body, i.e. The presence of a

• pacemakers and defibrillators,
• inner ear implants (if they contain ferromagnetics or the material of the device is unknown),
• vascular steel clips on the aneurysm,

• any metal fragments, bullets in the human body, including small metal shavings inside the eye orbit (occupational cause requiring prior skull x-rays in the employee).

Relative contraindications are contraindications related to the patient's condition and the presence of devices and appliances that should not change their properties under the influence of the magnetic field or affect it in any way. These include artificial joints, neurostimulators, insulin pumps, cardiac pacemakers, hemostatic clips and vascular stents, non-ferromagnetic implants. Questions may also arise about dentures, steel plates and spokes used in orthopedic treatment, permanent makeup, and tattoos, where ferromagnetic materials may be used.

In all of the above cases, the doctor should be informed in advance, if possible, indicating what metal the device is made of, what colors for makeup and tattoos were used, ie any information that will help to secure the procedure and make its results as reliable as possible.

MRI of the temporomandibular joint is not performed in case of severe claustrophobia and severe condition of the patient, when procedures to maintain life support of the body are required. In pregnancy, the possible risks will need to be discussed with the doctor, although in general they are small, given the safety of a magnetic field of such strength for humans and the distance of the fetus from the examined area of the body (head). [3]

Care after the procedure

Given the safety of the magnetic field and the tomograph itself, there are no consequences after the procedure. MRI-diagnostics has become so popular because, in the absence of side effects during and after the procedure, it allows you to identify pathologies that are not available to other diagnostic methods. The only unpleasant consequence may be a series of poor-quality images, if the patient did not observe immobility or concealed the presence of metal objects in the body.

Complications after the procedure are also possible only if the patient does not heed the doctor's warnings. There are few contraindications to the examination, but they must be taken into account. Magnetic field can disable the device, which may support the functionality of certain organs. For example, if the pacemaker malfunctions, the heart will malfunction, which can lead to a serious condition and even death of the patient.

On the other hand, any piece of ferromagnetic material can affect the magnetic field, distorting the results of tests. If the doctor relies on them, there is a risk of misdiagnosis and treatment that is not appropriate for the situation.

Specific care after the MRI procedure of the temporomandibular joint is not required. The main thing is that the results of the study help to identify the problem and subsequently restore health and joy of existence.