Laryngeal MRI is a method of noninvasive visualization of the initial respiratory tract, based on the ability of hydrogen atom nuclei in tissues to absorb and emit radiofrequency energy in an external magnetic field. Allows you to evaluate the structure of the structural elements of the larynx (cartilage, laryngeal ventricles, vocal folds, subcladal space) and detect pathological processes developing in them. By means of MRI, tumors, foreign bodies, lesions, abscesses, stenoses, anomalies of the structure of the larynx can be detected. It is performed when holding the breath on inspiration or during phonation.
Indications
The study is used to obtain information about the condition and anatomical features of the larynx, to visualize cartilage, their joints, ligaments, muscles, as well as lymphatic and blood vessels, in some cases – nearby soft tissues, larynx, esophagus, trachea. Laryngeal MRI helps to diagnose tumors, pathological processes of various etiologies, injuries and their consequences, postoperative complications, changes in lymph nodes. If necessary, a second examination is carried out. To clarify the diagnosis or the nature of the pathology, it can be performed several times without any harm to the patient.
Most often, an laryngeal MRI is prescribed in order to detect a tumor and assess its prevalence. The images allow you to visualize neoplasia at the earliest stages, to determine not only its localization, shape, size, but also its structure. Diagnosis is indicated for developmental abnormalities, inflammation, edema, to establish the cause of difficulty inhaling and exhaling, visualization of foreign bodies. With the help of an laryngeal MRI, severe laryngitis, pharyngitis with laryngopharyngeal lesion is diagnosed. At the same time, if there are indications, the condition of the larynx, salivary glands, upper trachea and esophagus, thyroid and parathyroid glands can be assessed. The study of neighboring anatomical structures is performed when a laryngeal tumor grows into nearby organs and tissues or when there are anomalies in the structure and location of the larynx.
Contraindications
Despite the absence of radiation exposure during the manipulation, it is prescribed to pregnant women only when absolutely necessary, because the effect of the magnetic field on the fetus has not been reliably studied. MRI is contraindicated if there are metal structures, metal-containing implants, dentures, braces, pacemakers and hearing implants in the patient’s body, since the magnetic field affects metal objects and the operation of complex devices, can cause them to heat up and even move.
Tomography is not performed on subjects weighing more than 120 kg, which is due to the technical capabilities of the tomograph (with the exception of devices with increased load capacity). The procedure is not performed for patients with mental disorders with possible involuntary motor activity. In case of claustrophobia, diagnosis in an open-type tomograph is recommended. Contrast-enhanced MRI is not indicated for allergy to the injected contrast agent. With a high degree of caution, a study with contrast is prescribed to patients with renal insufficiency, severe liver dysfunction, diabetes mellitus.
Preparation
Manipulation is carried out both without contrast enhancement and using contrast. Contrast-free laryngeal MRI does not require special training. Before the contrast study, the patient is advised to refrain from eating for several hours, a skin test is carried out to detect allergies to contrast. On the eve of an laryngeal MRI, ENT organs are examined, ultrasound or ENT endoscopy is prescribed. Before contrast examination, kidney function is evaluated. It is necessary to have the results of all previously performed diagnostic procedures with you. They come to the larynx MRI in comfortable clothes without metal threads and inserts. In some clinics, during the manipulation, the patient is offered to change into special underwear.
Methodology of conducting
Before an laryngeal MRI, it is necessary to remove all metal jewelry, watches, electronic devices, warn the doctor about the presence of fixed prostheses, metal structures and metal-containing implants, as well as pacemakers in the body. Restless patients may be offered sedatives. For younger children, patients with mental disorders, the procedure can be performed under anesthesia. During an laryngeal MRI, the patient lies motionless on a mobile tomograph table. At the time of scanning, the table is automatically passed through the tunnel of the device equipped with a two-way voice communication device. The results of the study are transmitted to a computer, where special programs are used to construct a 3D image displayed on the screen.
The whole procedure takes about 30 minutes, with contrasting its duration is lengthened. Before the contrast study, a contrast tolerance test is carried out, if its result is negative, a contrast agent is injected intravenously, wait a few minutes for it to be evenly distributed and tint the tissues of the area under study for a clearer image, and then scan the larynx area. The contrast can be administered through a catheter, which is left in the vein in case repeated or continuous administration of the drug is necessary. After processing the results, the doctor sees a layered three-dimensional image of the area under study.
Interpretation of results
It usually takes less than 24 hours to decrypt the data and prepare a conclusion. If, according to the laryngeal MRI, there are no inflammatory, destructive, degenerative processes, neoplasms, lymph node damage, vascular thrombosis, then the result is interpreted as the norm. If any pathological processes are detected in the larynx and nearby soft tissues, the results of the study are transmitted to the attending physician, who develops a plan for further management of the patient: draws up a program of therapeutic measures, sends for consultation to narrow specialists, hospitalizes as planned or urgently. The examined person is given pictures and an extract with a detailed description of the course of the manipulation and its results. At the request of the patient, the 3D image is stored on an electronic medium.
