Medical research and diagnostics

Computed tomography (CT) scan of the temporomandibular joint

Computed tomography of the temporomandibular joint belongs to the category of non-invasive diagnostics according to the principle of x-ray examination.

A briefly similar procedure is simply called CT TMJ. It is aimed at studying a potentially affected area with the involvement of radioactive radiation.

Despite the fact that the technique refers to the camp is relatively safe, it should be carried out only at the direction of the doctor.

Otherwise, you can only increase the risks of the negative impact of radiation particles on the sensitive parotid glands.

The test results allow us to finally confirm or refute medical suspicions regarding the growth of neoplasms.

Due to the high-precision technology, it is possible to transmit visual information on the screen on the presence of even tiny tumors with low density.

Expected Outcomes

For the convenience of reading the incoming data when examining an alleged pathological lesion in the jaw, information is visualized by displaying on a computer screen.

The projection is of three types: frontal, axial, sagittal.

All together allows you to evaluate not only the current state of the joint space. Due to the triangular projection, it is possible to identify the shape, as well as the surface composition of the joint and the size of the possible neoplasm.

If we take only one plane, then it will not work out with the shape and localization of the poles of the heads of the temporomandibular joint.

The only significant drawback of modern diagnostics is called blurry shadows, which sometimes makes it difficult to make a final diagnosis. We are talking about layers that are located in the areas of the medial and lateral poles. The first option covers the stony lobe of the temporal bone, and the second - an array of the cheekbones arc.

To exclude the risks of a false-positive result, the doctor must repeat computed tomography until the scope of the part being studied becomes more clearly visible.

The mechanism of coverage of a layered image of tissues is based on the attraction of x-rays. A potential problem area is highlighted by an ionizing beam. For a complete picture of what is happening, he highlights in different directions, doing this thanks to the rearrangement of the x-ray tube.

Due to the presented cooperation, electromagnetic waves are captured by special sensors. They direct incoming pulses to the computer screen, building a three-dimensional image.

Built visualization allows you to find a number of deviations, among which the most common are:

  • deviation from the norm of the width of the joint space;
  • bone pathology;
  • displacement of the articular heads in a calm state and with an open mouth;
  • anomalies of the articular disc;
  • the changed sizes of the heads of the joint of the lower jaw.

The results obtained help to identify ailments both in terms of morphology and in terms of structural changes.

When is the time to be examined?

A doctor will never begin to prescribe a computed tomography of a computer nature. The method is resorted to only in justified situations, when it is necessary to urgently determine whether the victim has a pathology, or to confirm the diagnosis. Also, the results will help clarify information on a potentially painful area, which in the future will lay the foundation for a successful course of intensive care.

Often the reasons for writing out a referral for testing are the following aspects:

  • suspicion of cancer;
  • diagnosis of structural anomalies of the joint, both congenital and acquired;
  • search for a suspected focus of inflammation;
  • preparatory stage of dental implantation;
  • dystrophic changes of the temporomandibular joint;
  • problems with jaw functionality.

Besides the fact that the diagnosis provides information regarding the alleged affected area, it also provides data on the state of the nearest muscle tissue. This is useful for those patients who came for examination with a referral from an oncological clinic, because the picture will show metastases if they exist.

Since this is a rather serious, lengthy and expensive test, it is not prescribed as a prophylaxis. The doctor will give a referral only after listening to the victim’s complaints, the results of a standard set of tests and reading the patient’s medical records.

Typical symptoms indicative of possible deviations of the system include: joint dysfunction, joint injury, pain in the jaw, pain in the cheekbones, impaired jaw mobility, malfunctions of the temperature regime, facial asymmetry.

But if a narrow specialist already recommended to undergo a CT scan, then you should not postpone a visit to the diagnostic room. In some diseases, progress occurs literally in a few weeks, which, if you ignore the medical prescription, guarantees numerous complications.

Especially often, early diagnosis helps cancer patients. When a doctor "catches" an ailment at the initial stage of development, the percentage of successful outcome of therapy rises several times.

Otherwise, the patient patient can reach the metastases of neighboring tissues and organs, which leads to extensive lesions and necrosis.

Preparatory stage

Before you go directly to the procedure, you should check with your doctor if the event will be contrasted. If the doctor insists on such an in-depth study, then the preparation will stretch for several days.

Before using a special contrast agent to obtain a clearer image of a CT scan, a person must pass a biochemical blood test. Such a precaution will establish the current level of urea and creatinine in the blood.

Here you can not do without standard allergic tests, which are designed to reduce the risks of a local reaction of the body, which provokes a mandatory decline in performance. Also, a few days before the appointed day, you must begin to adhere to a special therapeutic diet. And on the day of the diagnosis, patients refuse to drink.

But if the doctor insists on performing a tomography without using contrast, then no special preparatory measures will be required.

Before the procedure itself, the diagnostician will definitely ask you to temporarily remove any metal objects from the body, starting from jewelry and ending with dentures. All objects made of metal significantly reduce visibility, which affects the distortion of the finished image. Because of this, people are offered to change into cotton pajamas on the spot.

The study is carried out in a horizontal position on a comfortable couch. Moreover, it is worthwhile to prepare for the fact that the doctor will ask the ward to lie still for some time.

CT scan mechanism

Usually computed tomography without taking into account preparatory measures is done no more than ten minutes. But if the stage of contrasting is attached to the examination, then you have to wait about half an hour. You should not be afraid of a feeling of nausea and dizziness, which are typical consequences after the administration of a substance for analysis.

After the victim is placed on the couch, it is transported to a special hardware space where direct information is read. During the procedure, the couch will rotate in a circular mode so that X-ray radiation can reach the alleged affected area from all sides.

As a result, a layered image of the pathological focus without the effect of superposition is displayed on the screen, which guarantees increased clarity of the borders of the lesion.

If the victim needs to get an opinion quickly, then an encrypted document can be issued to him in about an hour. But usually, diagnosticians send their findings directly to the attending physician the next day. Already in place, the doctor, based on the results obtained, patient complaints and other indirect evidence, makes a final verdict.

In especially advanced cases, the specialist sometimes additionally after the CT sends the ward to an MRI to completely eliminate the risk of a possible medical error or visual error. Particularly relevant is the combination of two advanced medical technologies when rare genetic abnormalities or cancer tumors are suspected. Since CT is aimed only at the study of bone and articular structure, MRI will provide a clear picture of the state of soft tissues. Together, the tests are designed to exclude the possibility of an extensive inflammatory process in areas adjacent to the site of inflammation.

But sometimes it happens that even enhanced measures are not enough. Then the victim is sent to computed tomography again. And already, on the basis of a double study, they are diagnosed with the subsequent placement of medical, rehabilitation therapy.

Contraindications for use

Despite the fact that the presented non-invasive method belongs to the camp safe for health, some categories of citizens are at risk.

This is especially true for pregnant women, to whom even minimal radiation exposure can seriously harm, provoking pathologies of the development of the fetus. According to the same principle, abandonment of a therapeutic event should be given to ladies during lactation.

Also, before prescribing a diagnosis, the doctor must check with the patient, or consult a medical card to exclude other factors of contraindications. The list includes:

  • body weight more than 120 kg;
  • individual intolerance of the components of the contrast solution;
  • renal failure;
  • nervous disorders;
  • relapse of a chronic disease.

Cases are considered separately when the benefit of the procedure is several times higher than the relative contraindications. Everything happens at the discretion of the attending physician, who knows the characteristics of the ward's body and his medical history.

Useful Tips

Experienced doctors claim that some patients experience mild discomfort during testing for TMJ.

In order to avoid situations when, in an attempt to change the pose, a person shifts and the projected image is blurred, the technicians were mounted in the assistant's apparatus. This is a two-way microphone.

If a person on the couch suddenly becomes ill, has a seizure, or something else has happened, he is obliged to immediately inform the duty diagnostician about this.

It is also worth understanding the request of an expert to hold his breath. This approach increases the information content of the results, if you strictly follow instructions. Otherwise, you have to re-analyze.

Despite the fact that even when attracting contrast, you do not need to refuse to take your usual medicines, the doctor should still tell you which drugs the patient is taking. This is necessary to compile a detailed clinical picture.

Do not be surprised even by a sudden rash on the skin after the administration of a contrast medium. This phenomenon is temporary. Irritation will pass immediately after the kidneys process the radioactive liquid and remove the inactive metabolites naturally.

Against the background of the request to remain motionless during the entire scanning period, the presented method is not suitable for children and elderly people. They are more often prescribed a classic ultrasound examination of a problem area.

Watch the video: CNO3: MRI & CBCT TMJ Imaging: "How to determine if a patient possesses stable & adapted TMJ's" (December 2019).