In addition to the computer tomography (CT) of lungs in diagnostics of COVID-19 also other methods of visualization, such as positron emission tomography (PET), ultrasonic diagnostics of lungs and magnetic resonance imaging (MRI) are used. In this article we will sort these methods and their features.
PET/KT
The Positron Emission Tomography (PET) is a sensitive, but invasive method of visualization which plays an important role in assessment of inflammatory and infectious diseases of lungs, monitoring of progressing of a disease and effect of treatment and also in improvement of treatment of patients. It is established that the coronavirus of SARS-CoV-2 causes inflammatory processes and considerably increases the level of mediators of inflammation that indicates that the positron emission tomography 18F-FDG can be the effective tool for visualization of COVID-19. There are messages that damages of lungs at patients with the pneumonia caused by COVID-19 were characterized by high absorption 18F-FDG, at the same time the lymph node was involved, disseminate defeat was not revealed at visualization 18F-FDG PET/KT. Specialists assume that inspection by means of 18F-FDG PET/KT can play a supporting diagnostic role in COVID-19, especially at an early stage when differential diagnostics is complicated. Further researches are necessary for definition of whether is 18F-FDG PET/KT a suitable method of testing for existence of COVID-19. Now this diagnostic method is not recommended to be used.
Ultrasonography of lungs
As the noninvasive, not demanding radiation and a portable method of visualization of ultrasonography of lungs allows to conduct primary examination of the patients belonging to group of low risk, diagnostics at patients with suspicion of pneumonia in emergency department, to carry out predictive stratification and to watch dynamics of development of pneumonia. A number of authors reported that results of ultrasound examination of lungs are similar to the results of KT which are carried out for assessment of the pneumonia caused by COVID-19. For the patients who are in a serious or critical state especially for those which are hospitalized in intensive care unit and need ventilation, ultrasonography of lungs is the obligatory tool for observation and control of efficiency of treatment. What is even more important, use of ultrasonography can reduce risk of contact between the infected patients and health workers and also differentiate patients on risk groups. Pregnant women with suspicion on COVID-19 should avoid whenever possible carrying out KT of a thorax because of high risk of radiation of a fruit therefore some authors as an alternative recommended to obstetricians and gynecologists to conduct examination of lungs with ultrasonography use.
MPT
The Magnetic Resonance Imaging (MRI) — an effective method of visualization of soft tissues without radiation. However it usually is not applied to diagnostics of COVID-19 because of a long time of scanning and high cost in comparison with a computer tomography and ultrasonography. Nevertheless, noninvasive MRT can be applicable for diagnostics of COVID-19 at children and pregnant women. The Koronavirusny infection of SARS-CoV-2 generally affects lungs, however autopsies showed that the infection affects also heart, vessels, a liver, kidneys and other bodies. As now it is well known, at molecular level in several bodies angiotensin - the converting enzyme 2 (APF2) which is a key receptor and a key entry point in a coronavirus cell is revealed. When carrying out MRT heart at patients with COVID-19 disturbances of warm activity, such as acute myocarditis and pericardis with systolic dysfunction were also revealed. The researches of indicators of RNA conducted by a number of authors showed that in addition to lungs other bodies are also subject to risk, in particular, heart, a gullet, kidneys, a bladder and an ileal gut. Thanks to high precision of visualization of structures and conditions of various soft tissues, MRT it is possible to use for studying of the bodies, the most vulnerable to a koronavirusny infection that allows to understand better a pathogeny and mechanisms of its development. Meanwhile, in cases of a severe form of pneumonia it is possible to estimate data of MPT, KT and X-ray analysis, to compare values and indicators of ultrasonography, a X-ray analysis, KT and MPT. Carrying out a number of researches for sick COVID-19 for the purpose of comparison of mechanisms of this pathology and a systematic research of the bodies subject to complications from a coronavirus is advisable.