What is kate in medicine? The difference between computed tomography and magnetic resonance imaging

MRI and CT are diagnostic methods that visualize the brain and show its structure and pathologies. Both methods are digital: the data obtained is processed in a computer and displayed on the screen. Both methods provide a layer-by-layer image of the brain. Despite these similarities and the unifying word “tomography”, these methods are based on different physical elements and phenomena.

To understand the difference between the methods, you should look at each of them. is a non-invasive way to diagnose brain diseases. The method is based on the influence magnetic field on the body.

Researchers realized that hydrogen atoms can change their position under the influence of electromagnetic force. The change in direction of hydrogen protons is recorded by magnetic tomograph sensors. The information is sent to a computer and then displayed on a monitor as an image, where the brain is shown in a series of images, layered and three-dimensionally.

It is based on the phenomenon of X-rays. Each tissue in the body has its own density, which means resistance and degree of absorption. When the rays are directed toward the body, brain tissue absorbs them differently. This difference and contrast between the degree of absorption is displayed in the final image as dark and light areas. Computed tomography is a type of radiography, only digital. That is, the process of obtaining an image differs from classical x-ray diagnostics: the image is digitized. The result is an image of better quality and higher resolution.

MRI or CT, if we talk about the functional purpose, magnetic resonance imaging is more intended for studying the soft tissues of the brain. For clarity, the following indications are given:

• volumetric processes inside the skull: tumors, cysts;
• acute circulatory disorder: hemorrhagic and ischemic stroke, subarachnoid hemorrhage;
• expansion and asymmetry of the ventricles of the brain;
• study of cerebral vessels, their patency and blood flow in pools;
• condition of the spinal canal, liquor dynamics;
• mapping of the cerebral cortex, which makes it possible to study individual characteristics the structure of the parts of the brain that are responsible for mental and mental processes.

Computed tomography has other indications:

1. skull trauma: fractures, bone cracks;
2. diseases of the cervical vertebrae;
3. vascular obstruction, atherosclerosis;
4. headache and fainting;
5. violation mental state and behavior: alcoholism, neurological deficit;
6. intracranial hypertension;
7. cramps with severe headaches.

The difference is clear from the indications: MRI is more suitable for studying functional states and temporary disorders of the brain, while CT is more suitable for static organic brain damage. Therefore, it is impossible to say which is better: the methods have different purposes. It is impossible to compare different categories.

The doctor prescribes a study based on objective data and indications. For example, if a tumor is suspected, it is better to do magnetic tomography: it visualizes better soft fabrics. If a person has fallen and there is a wound at the site of the impact, his consciousness is impaired and he is feeling sick, it is more informative to do a computed tomography scan: it better shows bone fractures and vascular injury.

The difference between MRI and CT in terms of contraindications:

• Magnetic resonance imaging cannot be done with: an implanted or external pacemaker, middle ear implants, magnetic fragments in the skull, heart failure, patient inadequacy, psychotic state, prostheses in the heart, endoprostheses.
• Computed tomography cannot be done if: there is pregnancy, the patient is too heavy, renal and liver failure, illness thyroid gland, patient inadequacy, decompensation diabetes mellitus, multiple myeloma.

Conclusion: it is impossible to say which is better. Each method has its own advantage and purpose.

Which is safer: CT or MRI?

Computed tomography uses X-rays. They ionize tissues. One of the properties of ionizing radiation is the formation of free radicals that destroy proteins and nucleic acids. Theoretically, in large doses this leads to gene mutation, the development of tumors and the development of radiation sickness. However, the dose emanating from the tomograph per examination is so low that the likelihood of developing cancer approaches zero.

MRI uses a magnetic field that is completely safe for the body. Moreover, a person encounters a magnetic field every day: the Sun, storms, the Earth’s magnetic field.

Conclusion: Both methods are safe, but MRI is safer than CT.

EEG or MRI

It's impossible to say which is better: the two methods study different properties of the brain. It can be argued that they approach the central nervous system from two sides. Magnetic resonance imaging depicts the brain as an organ, its structure and function and belongs to the family of neuroimaging techniques.

Electroencephalography is also a non-invasive method, but it does not image the brain. The purpose of an EEG is to study the electrical activity of the brain. The MRI results are shown on a computer and in images that show the brain layer by layer. The results of electroencephalography are depicted on a long tape - an electroencephalogram. It shows electrical activity, which is generated by the brain.

This tape has the following rhythms: alpha, beta, gamma, delta, theta, mu and sigma. Each of these rhythms reflects a different functional state brain, and some – pathology of the nervous system. For example, the delta rhythm is fixed when deep sleep, the mu rhythm is often observed in children with autism.

MRI or MSCT of the brain

is a modern version of computed tomography. They have two or more sensors for recording X-ray absorption. That is, the method is based on the phenomenon ionized radiation, which differs from the operating principle of a magnetic tomograph. MRI is based on the effect of a magnetic field on hydrogen protons, which change their spatial configuration.

The resulting images from the two research methods are similar to each other: they are high resolution, high scanning speed, increased signal-to-noise ratio, large scanning area. Speaking of safety, the magnetic field of an MRI is not harmful. MSCT has a radiation dose, although it is less than its predecessor - classical computed tomography.

MRI and MSCT are similar. However, magnetic resonance imaging has a key advantage: the method better visualizes the brain and spinal cord. A multislice tomograph also detects pathologies of the central nervous system, but MRI is much more sensitive.

Conclusion: both methods have almost the same diagnostic points applications. Answering the question which is better, based on the fact that MRI visualizes better nervous system, it can be argued that magnetic resonance imaging has an advantage over multislice tomography, although not significant.

Before identifying the difference between MRI and CT, it is necessary to understand what these two types of diagnostics are.

CT (computed tomography) is a sequential scan of both individual areas of the body and the entire body (general scan) using X-ray irradiation. There are two types of scanning - with a substance (contrast) and ordinary, without the use of additional substances and equipment. The procedure is carried out using a capsule, spiral tomograph; the number of spirals (4, 8, 16, 64) directly affects the diagnostic object (heart, intestines, brain).

MRI (magnetic resonance scanning) is best method diagnostics to monitor the condition of soft tissues. The description of the diagnostic method immediately contains the answer to the first question: “What is the difference?” - X-ray radiation is not used, a picture of the state of the body is obtained through the magnetic field and the position of radio frequencies. During the procedure, the person is placed in a special capsule, closed tunnel, in which he is scanned.

What is the difference between CT and MRI:

What is the difference between CT and MRI - contraindications

Like any examination method, MRI and CT have their own number of contraindications that prohibit the procedure.

When is it better to refuse magnetic resonance therapy:

If you need to undergo a CT examination, not a single doctor will refuse you, because the technique has no contraindications. It is prohibited only in rare, purely individual cases.

The second difference is the difference in contraindications or their complete absence for CT (except for pregnancy and allergies to contrast).

Difference in preparation between CT and MRI

Before a CT scan, you must strictly refuse to eat or drink any liquids (3-4 hours before). The exception is the study of the digestive tract.

Before an MRI, you should always not eat for 3-4 hours. Before the actual procedure, it is necessary to remove metal objects and removable implants for diagnostic accuracy and safety for the patient.

What is the difference between CT and MRI - methods of preparation for diagnostics.

Carrying out CT and MRI procedures

During a visit to the room for diagnosis using MRI, you remove things that are harmful to the diagnosis, and perhaps undress to the waist. Lie down on the retractable table of the device and you are loaded into the tunnel.

The examination is quite long (25-40 minutes), there is little space inside, so it is better for those suffering from claustrophobia to refrain. The device has a built-in video transmitter and a special microphone for communication with a doctor. The results are ready in a day, you can pick them up yourself, or your doctor will have them. Sometimes an injection of a special solution (5-15 ml) is required to highlight the organ (MRI with contrast).

Before a CT scan there are no strict limits regarding implants and prostheses. The patient lies down on a mechanical couch, which is guided in different ways to the tomograph. There is plenty of space left, so attacks of claustrophobia are excluded. The duration of the procedure is maximum 10 minutes. Results are obtained almost immediately.

If we talk about the specifics of the techniques, the main differences between them are: the speed of the examination (CT takes less time), the speed of obtaining the result, the amount of free space (especially important for those suffering from claustrophobia) and the type of equipment.

Disadvantages of MRI and CT - where to look for their weak points?

Modern medicine is quite developed, but there is no diagnostics in the world that is 100% ideal; each has its own advantages and disadvantages.

Errors of MRI diagnostics:

• A large list of contraindications, the impossibility of carrying out in the presence of any artificial material in the body (false teeth, pacemaker, prosthetic limbs, piercing).
• Duration of the procedure (25-40 minutes).

Negative side of CT diagnostics:

• The use of X-rays, although not very harmful, is irradiation.
• Inability to study the entire spine (too high radiation dose required).
• Strictly contraindicated for pregnant women.

The next difference is that MRI is harmless, but contraindications may prevent the procedure from being prescribed; it lasts longer than CT. And computed tomography is not suitable for the spine and is not completely harmless.

Differences between CT and MRI appointments

For comparative analysis It is important to know what diseases can be detected by each method.

Indications for computed tomography:

• Disorders of the musculoskeletal system and joint diseases. Helps identify arthrosis, arthritis, ankylosing spondylitis, osteochondrosis and more. Despite the fact that it is impossible to completely scan the spine. The technique remains one of the most accurate, the first to detect a violation bone apparatus.
• Tumors, growths, bone deformation.
• Injuries, damage to the human skeletal body - fractures, cracks in the bones, dislocations, deviations that occurred due to mechanical stress - are identified after receiving the results.
• Changes in the structure and functioning of blood vessels at the atherosclerotic level.
• When examining the soft tissues of the respiratory apparatus, gastrointestinal tract and genital and urinary organs, a contrast study is performed.

When is magnetic resonance therapy needed:

• If tumors, cysts, growths of soft tissue (muscles, organs, adipose tissue) are suspected, the procedure is prescribed only after an initial examination and preliminary results ultrasound examination.
• To monitor the condition and quality of brain function (not only physical factors, but also mental). For example, people with schizophrenia have strong activity in the area of ​​the brain responsible for hearing and vision - this indicates hallucinations.
• To detect spinal cord disorders.
• To identify pathologies of soft cartilage of the vertebrae and intervertebral discs.

This difference speaks to the exclusivity of each of the methods - they are very different and each of them is required for certain pathologies.

How is CT different from MRI - which is better?

A difficult question, because each of the diagnostics is good at what it does. So better than MRI or CT?

MRI gives more accurate results in diseases and is recommended if:

CT will be more effective if:

• Mechanical damage, brain injury and cranium.
• Damage to the bone apparatus, its deformation due to mechanical stress.
• Research vascular system, hearts.
• Purulent diseases- sinusitis, otitis.
• Pathologies in abdominal cavity.
• Negative changes in the respiratory organs - bronchi, lungs.
• Cancer, degenerative changes chest and its organs.

If a full examination of soft, connective, and fatty tissues is required, then it is better to choose MRI.

It is harmless to the body and does not charge the body with a small dose of radiation, like computed tomography. An excellent replacement for contrast CT if individual intolerance or contraindications are identified.

CT has a more intense effect on the body, but if you need to examine the musculoskeletal system, respiratory system, abdominal cavity - becomes a choice.

It is impossible to say which is better, but they are different. These are two absolutely different techniques studies that differ in the type of contraindications, indications, and method of exposure. Based on the characteristics of these diagnostics, as well as your medical history, the doctor decides which type of examination will be effective in your case. The main thing is to get examined regularly and monitor your health.

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Hardware diagnostics allows you to see organs from the inside. This makes it possible to more accurately determine the degree of damage and the course of therapeutic manipulations. Medical errors and incorrect diagnoses are a thing of the past: modern medicine has several types of diagnostic devices. Let's look at the difference between CT and MRI. Which type of scanning is more informative, and which is safer for health?

Computed and resonance tomography

A CT scan is a computed tomography scan that scans the internal organs of the body using x-rays. Unlike conventional radiography, the device provides a three-dimensional image instead of a two-dimensional one. The device takes a whole series of images from different viewing angles, which are processed by a computer program. As a result, the doctor receives a three-dimensional image of the organ being examined.

The patient is placed on a special couch, around which a ring-shaped device is located. X-rays scan the patient from all sides. Depending on the program settings, you can obtain not only an image of the entire organ, but also a section of it. All this allows you to get the most accurate picture of the state of the organs.

MRI is magnetic resonance imaging. How does CT differ from MRI? The difference between MRI and CT lies in the nature of the waves used - scanning with a tomograph is done using a magnetic field. Otherwise, the operating principle of the devices is similar: a computer program transforms wave signals into a three-dimensional image.

Note! The difference between CT and MRI is the different nature of the waves used to scan body organs.

However, differences in the nature of the waves are not everything. CT and MRI are used for diagnosis different types pathology. For example, MRI of the liver or computer diagnostics of joints.

CT is most often used to detect the following diseases:

• joints, spine, bones and teeth;
• injury internal organs;
• brain;
• thyroid gland;
• chest;
• abdominal organs;
• genitourinary organs;
• vessels.

CT scans well for tumors, cysts, and stones in organs. The examination of blood vessels and hollow organs is carried out by injecting a contrast agent, which highlights them in the image and allows for a better view of the affected areas.

Resonance diagnostics is used mainly for scanning soft tissues of the body:

• neoplasms;
• spinal cord and brain;
• muscles and ligaments;
• MRI of the liver;
• joint membranes.

Sometimes a hardware examination of an organ can be carried out using both tomographs - CT and MRI, for example, MRI and CT of the brain. What to choose - MRI or CT, which tomography is better? If there is no fundamental indication for diagnostics using a specific device, patients choose CT: resonance examination is more expensive.

Health safety

We found out what the difference is between CT and MRI. It consists of using various physical phenomena. Everyone knows what an x-ray is: it has been used in medicine for a long time. X-ray radiation is harmful to health, so you should not take pictures often. CT scans use X-rays, which is undoubtedly harmful to health.

The magnetic field used in resonance diagnostics is completely safe for health. The difference between an MR Tomograph and a CT scan makes it possible to examine the tissues of the lungs and other body organs for pregnant women and small children from birth. The only disadvantage of resonance diagnostics is the high price.

X-ray diagnostics (X-ray CT) is much cheaper, but it cannot be used too often. Magnetic survey can be performed repeatedly, for example, MRI of the liver during a course of therapy or in the postoperative period.

Disadvantages and contraindications

Despite their differences and similarities, both types of hardware scanning have their advantages and disadvantages. Let's take a closer look.

Disadvantages of resonant examination:

• it is impossible to examine a patient with metal implants;
• the result of scanning the hollow organs is not good enough (CT of the abdominal cavity is more effective, as is CT of the lungs);
• the patient must remain motionless for a long time.

Disadvantages of computer examination:

• differs from MRI due to harmful x-ray radiation;
• does not characterize the functionality of organs - only an image;
• Pregnant women and young children cannot be examined;
• Frequent use is contraindicated.

Before appointment, examinations are carried out lab tests to ensure the safety of both types of diagnostics. Despite the fact that MRI is better than CT, patients more often choose computer examination.

Contraindications to computer diagnostics:

• pregnancy/lactation;
• small children under 5 years old;
• limb in a cast;
• renal failure.

Contraindications to resonance diagnostics:

• mental disorders;
• claustrophobia - fear of closed spaces;
• their metal implants;
• obesity (more than 100 kg);
• first trimester of pregnancy;
• renal failure.

Note! Kidney failure is an obstacle to both diagnostics, if it involves the introduction of contrast agents into the body.

Preparation for the procedure

How to prepare for a CT scan correctly? There is no need to adhere to any special restrictions before the examination. Doctors recommend abstaining from heavy and rough food the night before and not drinking alcohol. Before visiting the diagnostic room, you must remove any jewelry. The examination is carried out without outer clothing.

Important! Computer examination does not provoke cancer.

How to prepare for a resonant examination? Here, the conditions for preliminary preparation are the same - do not drink alcohol on the eve of a visit to the doctor and do not eat hard-to-digest and solid foods. Before visiting the office, you must remove all accessories and jewelry from your body and pockets. If you have metal implants, the procedure is not performed - keep this in mind.

Contraindications to MRI are the presence of a tattoo with iron pigments, a pacemaker, and permanent makeup. Find out all the details of the resonance scan in advance.

Bottom line

Medicine has made great strides in the field of disease diagnosis thanks to the invention of advanced scanning devices. The modern century, characterized by an innovative approach to the examination of body systems and organs, has been marked by new discoveries in the field of radiography and tomography. How do new technologies differ from old ones? First of all, by obtaining a three-dimensional three-dimensional image of organs and their sections.

Now it has become possible to study pathology in detail, visually observing deviations in the structure of organs. It has also become possible to study the pathology of the functioning of the organ, for example, an MRI of the liver shows it Current state. However, there are differences between scanning machines: computer diagnostics better shows the image of solid and hollow structures of the body, and the resonant one shows the soft tissues of the body.

Choosing one or the other hardware examination depends largely on the organ or part of the body being examined. If diagnostics can be carried out using both devices, for example, CT and MRI of the brain, it is better to choose resonance scanning. The price of MRI is higher, but it is safer for health.

Modern diagnostic methods make it possible to detect diseases at initial stages. Nowadays, it is impossible to imagine medicine without two important abbreviations - CT and MRI. Considering that both diagnostic methods go hand in hand, people ignorant in medicine constantly confuse them and do not know which method to give preference to.

Many people believe that computed tomography and magnetic resonance imaging are identical. This is an erroneous statement.

In fact, they only have in common the word “tomography,” which means the production of images of layer-by-layer sections of the analyzed area.

After scanning, the data from the device is sent to a computer, as a result the doctor examines the images and draws conclusions. This is where the similarities between CT and MRI end. Their principles of action and indications for use are different.

How are both of these methods different?

To understand the differences, you need to understand the technique.

Computed tomography is based on x-ray radiation. That is, CT is similar to X-rays, but the tomograph has a different way of recognizing data, as well as increased radiation exposure.

During a CT scan, the selected area is treated with X-rays layer by layer. They pass through tissues, alternating densities, and are absorbed by the same tissues. As a result, the system receives layer-by-layer images of sections of the entire body. The computer processes this information and produces three-dimensional images.

MRI diagnostics is characterized by the influence nuclear magnetic resonance. The tomograph sends electromagnetic pulses, after which an effect occurs in the area under study, which is scanned and processed by the equipment, then displaying a three-dimensional image.

From the above it follows that MRI and CT have a significant difference. In addition, computed tomography cannot be performed repeatedly due to the large radiation exposure.

Another difference is the research time. If 10 seconds are enough to obtain a result using CT, then during the MRI process a person is in a closed “capsule” from 10 to 40 minutes. And it is important to remain completely still. This is why magnetic resonance imaging is not performed on people suffering from claustrophobia, and why children are often given anesthesia.

Equipment

Patients cannot always immediately determine which device is in front of them - MRI or CT. They are similar in appearance, but differ in design. The main component of a CT tomograph is a beam tube, and an MRI is an electromagnetic pulse generator. Magnetic resonance imaging scanners come in closed and open types. CT does not have divisions of this kind, but has its own subtypes: positor emission tomography, cone beam tomography, multilayer spiral tomography.

Indications for MRI and CT

Often the patient prefers the more expensive MRI method, believing that it is more effective. In fact, there are certain indications for conducting these studies.

MRI is prescribed to:

• Identify tumors in the body
• Determine the condition of the spinal cord membranes
• Study the nerves located inside the skull, as well as the structure of the connective tissues of the brain
• Analyze muscles and ligaments
• Examine patients with multiple sclerosis
• To study pathologies of the joint surface.

CT scans are prescribed to:

• Examine bone defects
• Determine the degree of joint damage
• Identify internal bleeding and injuries
• Examine the brain or spinal cord for damage
• Detect pneumonia, tuberculosis and other pathologies of the chest cavity
• Establish a diagnosis in the genitourinary system
• Identify vascular pathologies
• Study hollow organs.

Contraindications

Considering that a CT scan is nothing more than radiation exposure, it is not recommended pregnant women and during lactation.

Magnetic resonance imaging is not performed in the following situations:

• presence metal parts in the body and on the human body;
• claustrophobia;
• located in the tissue pacemakers and other electronic devices;
• sick, suffering nervous pathologies who, due to illness, are unable to remain stationary for a long time;
• patients weighing from 150-200 kg.

MRI and CT in questions and answers

• Is CT always better than X-ray?

If a patient has pulpitis in a tooth or a regular bone fracture, an x-ray is sufficient. If it is necessary to clarify the diagnosis of an unclear nature, to determine the exact location of the pathology, more information will be needed. And here a computed tomography scan is already shown. But final decision accepted by the doctor.

• Does CT scan produce radiation?

On the contrary, with computed tomography the radiation exposure is even higher than with simple x-ray. But this type of research is prescribed for a reason. This method used when there is a genuine medical need.

• Why is a contrast agent administered to a patient during a CT scan?

In black and white photographs, contrast helps create clear boundaries of organs and tissues. Before studying thick or small intestine, the patient's stomach is injected with a barium suspension into aqueous solution. However, non-hollow organs and vascular areas will require a different contrast. If the patient needs examination of the liver, blood vessels, brain, urinary tract and kidneys he is shown contrast in the form of an iodine preparation. But first, the doctor must make sure that there is no allergy to iodine.

• Which is more effective: MRI or CT?

These methods cannot be said to replace each other. They differ in the degree of sensitivity to certain systems of our body. Yes, MRI is diagnostic method, which gives better results when studying organs with a high fluid content, pelvic organs, and intervertebral discs. CT scans are prescribed to study the bone skeleton and lung tissue.

To establish accurate diagnosis for problems with the digestive organs, kidneys, neck, CT and MRI are often equal in importance. But CT is considered more in a fast way diagnostics and is suitable for cases where there is no time to scan with a magnetic resonance imaging scanner.

• Is MRI safer than CT?

With magnetic resonance imaging, radiation exposure is excluded. But it is worth understanding that this is a young diagnostic method, so it is still difficult to determine what consequences it has for the body. In addition, MRI has more contraindications (presence of metal implants in the body, claustrophobia, installed pacemaker).

And finally, once again briefly about the differences between CT and MRI:

• CT involves x-rays, MRI uses an electromagnetic field.
• CT scans physical state selected area, MRI – chemical.
• MRI should be chosen for scanning soft tissues, CT for bones.
• With CT scanning, only the part being examined is located in the scanned device; with MRI, the entire human body is located.
• MRI is allowed to be performed more often than CT.
• MRI is not performed if there is claustrophobia, the presence of metal objects in the body, or a body weight of more than 200 kg. CT scanning is contraindicated in pregnant women.
• MRI is safer in terms of its impact on the body, but at present the consequences of the influence of the magnetic field have not been fully studied.

So, we have looked at the differences between MRI and CT. In any case, the choice in favor of one or another research method is made by the doctor based on the patient’s complaints and clinical picture.

Not every person knows what the difference is between computed tomography and MRI. And there is no strangeness in this. Both studies can show the condition of internal organs, and the devices themselves are similar in appearance. But the methods are based on radically different principles of influence on the body, so knowing what the difference is between CT and CT is useful for every educated person.

CT scan

Computed tomography is a diagnostic procedure that uses x-rays. The technique allows you to convert an analog image into a digital three-dimensional model in real time, “constructing” the patient’s body using cross-sectional images, the thickness of which can reach 1 mm.

When using X-rays, it was possible to obtain flat visualization, but CT allowed us to look into the body from different sides.

CT is sometimes called X-ray computed tomography (X-ray computed tomography).

Story

The creation of a computed tomograph became one of the most important discoveries of the past century. Its creators were awarded the Nobel Prize for the invention of a device that had greater information content with less harm.

Research in this area has been carried out since 1917, but only half a century later the world saw the first device, which was called an “EMR scanner” and was used exclusively for examining the head.

The idea of ​​studying an organism using cross sections is not new: the famous Russian scientist Pirogov became the founder topographic anatomy, when he made cuts on frozen corpses as part of a scientific experiment. Today, a CT machine allows for more accurate and faster visualization. The devices have been improved and modernized throughout their existence, and today the X-ray emitting device is accompanied by a complex software, which helps not only to create an image, but also to analyze it.

Disadvantages of the method

The study is universal and safe, and its only contraindication is its relatively high cost.

Among the objective disadvantages are:

• harmful x-ray radiation, although in smaller quantities than when performing the x-ray itself;
• not enough informative survey for hernias and inflammatory processes;
• there are contraindications;
• There are restrictions on body weight and volume.

To examine cavities in the body, a contrast agent is often used, which can be administered intravenously. With it, CT becomes more dangerous, since the contrast can cause allergic reactions and complications.

Advantages of the method

Today, computed tomography is one of the most common diagnostic procedures in the world. X-ray radiation in low doses causes virtually no harm to the body.

Typically, CT is not used at the first stage of diagnosis. First, a person undergoes laboratory tests and undergoes an ultrasound scan. And only in case of low efficiency of these methods, tomography is used to determine pathology. Therefore use X-ray method justified, because it carries less harm than the absence of a diagnosis.

Indications

Computed tomography is used to examine:

• brain;
• spine and neck;
• bones;
• peritoneal organs;
• pelvic organs;
• hearts;
• limbs.

The procedure allows you to identify injuries, tumors, cysts and stones. In most cases, CT is used to determine an accurate diagnosis.

Emergency indications for tomography include:

• suddenly developed convulsive syndrome;
• head injury followed by loss of consciousness;
• stroke;
• unusual headache;
• suspected damage to a blood vessel in the brain;
• severe body injury.

Routine indications include failure to respond to simpler tests or treatments. For example, if a patient continues to have a headache after long-term treatment, there is reason to believe that the diagnosis was made incorrectly. This means he needs a new study that will reveal the cause of the ailment more accurately.

Tomography can be used to monitor treatment, as well as to improve the safety of invasive diagnostic and treatment methods.

Contraindications

You should not check the condition of body tissues using CT during pregnancy, since Negative influence X-ray radiation to the fetus has long been studied and proven.

The remaining contraindications are associated with the introduction of a contrast agent into the body, which can lead to the development of complications (bleeding, severe allergic reaction, toxic shock) with:

• chronic renal failure;
• multiple myeloma;
• diabetes mellitus;
• anemia;
• tendency to allergic reactions.

CT scanning is not recommended for children, even if it is a procedure without contrast. But the decision must be made by the doctor: if the potential benefits of the study are higher than the risks, tomography can be performed.

Preparation

CT scan does not require extensive preparation, but the study will take place it is more effective if you do not eat food for several hours, especially if you plan to administer contrast.

During the body scan, you must lie still, so it is important to relax and calm yourself. If the patient is constantly taking any medications, he must inform the doctor in advance.

How does the procedure work?

During CT scanning, the patient lies on a special couch motionless throughout the entire procedure, the duration of which does not exceed 10-15 minutes. Usually, the patient is asked to expose the area of ​​the body that is planned to be examined, so it is better to go to the hospital wearing things that can be quickly taken off and put on.

The patient receives the results a few minutes after the procedure: both pictures and a conclusion.

Magnetic resonance imaging

After the advent of magnetic resonance imaging, patients had a question: what is the difference between CT and MRI, if both methods recreate a three-dimensional model of the body of a particular patient? The main difference is that MRI uses electromagnetic beams rather than X-rays. The method is based on response atomic nuclei(mainly hydrogen) in the body on the acting magnetic field.

Story

MRI was officially invented in 1973, and Nobel Prize in Medicine was awarded to the scientist P. Mansfield only in 2003. The process of creating the method involves the work of many scientists, but it was Mansfield who was the first to recreate the prototype of a modern MRI machine. True, it was very small in size, and only one finger could be examined in it.

After the prize was awarded, evidence was found that long before British scientists, MRI was invented by the Russian inventor Ivanov. He sent his calculations to the Commission on Inventions, but received a patent certificate only two decades later, in 1984, when MRI had already been officially invented abroad.

MRI was originally called NMR: nuclear magnetic resonance, but after the tragedy on Chernobyl nuclear power plant They decided to replace the name with a more neutral one.

Disadvantages of the method

The main disadvantage of MRI is the duration of the procedure, during which the person is in a confined space with high level noise. For sensitive patients, time in the device causes frequent by-effect: panic attack and even fainting. This result can be prevented if you are mentally prepared for the process and, with the doctor’s permission, take a mild sedative.

During the procedure, the doctor is in another room, but using a special device inside the tomograph, the patient can talk to him. For example, report your feeling unwell or listen to instructions, such as holding your breath.

Theoretically, there is a risk of injury during the procedure if the room is not equipped correctly and there are metal objects in it.

Advantages of the method

The main difference between CT and MRI is the absence of X-rays in the latter. This means that the number of restrictions on the procedure has decreased. Due to the safety of the magnetic resonance imaging scanner, it can be used to examine:

• pregnant women;
• children;
• nursing mothers;
• patients with any somatic pathologies.

Examination during lactation requires refusal breastfeeding child for 24 hours after the procedure.

Indications

MRI is used primarily to examine soft tissue, such as for tumors.

Nuclear tomography is used to identify pathologies:

• brain (including with diffusion and perfusion);
• spine;
• muscles and joints;
• abdominal organs;
• hearts.

The method can also be used during surgical interventions performed with the latest techniques.

Contraindications

Magnetic resonance imaging itself is not harmful or dangerous, but due to the specifics of the method, the body placed inside the device should not have anything metal on it or in it:

• jewelry and piercings;
• implants;
• pacemaker;
• surgical clamps;
• tattoos, the dyes of which could contain iron particles.

The exceptions are implanted teeth: They do not use iron, which can cause injury. As a rule, jaw prostheses are made of safe titanium.

The same contraindications are relevant for a nuclear tomograph as for a computer one: the procedure is technically impossible if the patient’s weight and dimensions exceed the norm. However, CT or MRI of the brain can be performed using a new device that only fits the head, and not the whole body. There are also open devices for diagnosing other organs, but the cost of testing them is quite high.

Preparation

Like CT, nuclear tomography does not require extensive preparation. If you plan to study the peritoneal organs, you need to give up foods for several days causing gas formation, and also take an anti-bloating pill. You should not eat food several hours before the appointed time.

Before the tomography, it is better to leave all metal jewelry at home and dress in simple clothes that are easy to take off.

If the patient experiences severe anxiety Before the procedure, you can drink a light sedative. It is good if a person finds out from the doctor in advance what awaits him: how long the scan will take, what discomfort may arise.

How does the procedure work?

Before the procedure, the patient takes off his clothes, wraps himself in a sheet provided by the doctor's assistant, and lies down on the couch. The specialist explains to him the procedure for performing a tomography, gives him a signal button in his hand, which he should press to urgently complete the procedure, and offers to insert earplugs into his ears.