MRI of the lumbar spine

Back pain, impaired mobility and sensitivity of the body in the lumbar region, difficulties with changing the posture, flexion and extension of the trunk are all symptoms that disrupt the habitual life, creating problems in everyday life and at work that limit the activity of a person. It is clear that a person can not endure such torment for a long time, therefore he seeks a doctor to find out the cause of the ailment and get qualified help. But how do doctors see the problems that are hidden inside the spine and often do not have specific external manifestations? Of course, with the help of an X-ray, CT or MRI of the lumbar spine - methods that allow you to see the situation from within and make an accurate diagnosis.

Which method to choose?

As you can see, doctors have not one, but as many as 3 opportunities to conduct an accurate diagnosis of spine diseases without damaging the skin and soft tissues. Modern medicine makes it possible to carry out such painless and effective diagnostic measures. But are they all equally effective and safe?

X-ray research is one of the oldest non-invasive methods for diagnosing internal diseases, which dates back to the end of the nineteenth century. Radiography is the transmission of internal structures of a person with the help of electromagnetic waves of length 10 ^-7 -10 ^-12 m (X-rays) followed by fixation of the result of the study on the film.

This method of research has been widely used due to its low cost and ease of diagnosis. But at the same time, everyone has known for a long time that radiography is not a safe procedure at all. Ionizing radiation has a harmful effect on the body, provoking the development of pathological processes in it.

In addition, with its help you can get only an ordinary static image on the plane, which does not allow in all details to assess the condition of the organ under study. The diagnosis is based on the study of the X-ray shadow (a shadow picture that repeats the contours of the internal organs of a person). But different internal structures can overlap each other and somewhat distort the picture.

Computer tomography is a more modern method of diagnosis, which appeared 77 years after radiography, which gives a layered image of the object of study. CT represents the possibility of obtaining a spatial image of the organ on the computer screen. This image can be rotated, viewed from different angles, to conduct a study in time (the duration of the procedure is very different from the X-ray, which takes only a couple of minutes).

The informativeness of such a diagnostic procedure is much higher, but the equipment for its carrying out is expensive, and not every clinic can afford it. It is clear that the cost of diagnostics will be much higher.

But that's not all. Despite the fact that in carrying out CT imaging the patient's radiation load on the patient's body is lower, the procedure actually remains essentially the same as the x-ray with the use of ionizing radiation, therefore the number of procedures is limited. In addition, future mothers such a study, as well as radiography, is not suitable, because it can have a bad effect on the development of the fetus.

Magnetic resonance imaging  is a method that is older than CT for only one year, but fundamentally differs from its predecessors in that the procedure does not use unsafe X-rays. The study is based on the properties of hydrogen atoms (and our body is half of them exactly) under the influence of the electromagnetic field to change its spin and give energy.

Different human organs have different numbers of hydrogen atoms, so the pictures of individual organs will differ. Different in density fabric will also give images of different shades. And if there is a tumor in the organ, a hernia, inflammation or displacement of bone structures takes place, it will all be reflected on the computer screen.

Thus, the picture of the MRI of the lumbar spine is nothing more than the reflection of electromagnetic rays from various internal structures of the organism in the lumbosacral region, which reproduces on the computer screen the response of hydrogen atoms to the action of the magnetic field. This picture allows you to determine the slightest changes characteristic of the initial stage of the disease of the spine or nearby structures, and those that speak of the neglect of the process.

If there is a suspicion of a tumor process in the lumbar region or if it is required to detail the pathways of metastatic spread after removal of the tumor, the MRI procedure is performed with contrasting (in principle, the same is possible with an X-ray or CT), for which gadolinium or oxide preparations gland. The introduction of contrast is also useful for monitoring the condition of the spine after removal of the intervertebral hernia.

In any case, MRI can detect more or less dangerous pathologies, be it inflammatory-degenerative changes in the spine, congenital anomalies, malignant or benign tumors, or the result of spine trauma. Such diagnostics make it possible to make an accurate diagnosis in order to assess the possible consequences of the disease and develop an effective plan for its treatment.

The electromagnetic radiation of the MR-tomograph, in contrast to the X-rays used in radiography and computer braking, does not harm our body, which means that such research can be carried out without fear of the required number of times. It is suitable for diagnosing spine diseases in children and pregnant women, since it has a minimum of contraindications and side effects.

Despite the fact that the cost of MRI, like a computer tomogram, is significantly higher than the price of a film for carrying out a spine X-ray, this study gives much more information to the doctor and allows us to reveal hidden disturbances that can not be viewed by an ordinary X-ray machine. In addition, during the MRI, the patient has the opportunity to get on hand two types of information carrier: a static image on photographic paper and spatio-temporal on a digital medium (computer disk, flash drive).

The advantages of CT and MRI in front of the usual X-ray study are undeniable. Therefore, whenever possible, it is recommended to resort to more modern diagnostic methods. In some cases, for example, when examining the chest and lungs, CT is considered preferable. To study changes in the lumbosacral area, both methods are considered equally effective and approximately equal in cost (any scanner is considered expensive equipment), so everything usually rests on the degree of safety and desire of the patient himself.

Indications for the procedure

The lumbar spine includes five consecutive vertebrae, which are separated by intervertebral discs. Further, it is followed by the sacral section, consisting of 5 joints in one common bone, and the coccyx (a rudimentary organ similar in structure to the sacrum but smaller in size).

In fact, the  lumbar region  is the lowest movable part of the human spine, which accounts for the greatest burden, therefore, the reasons for pain in the back and lower back are often associated with it. The bones themselves can not hurt themselves, but in addition to the bony structures in the form of vertebrae and intervertebral discs, the lumbar-sacral region includes ligaments, tendons, nerves, muscles, blood vessels that can be traumatized by vertebral shear or degenerative changes in bone-cartilaginous structures.

The proximity of the lumbar and sacral parts of the spine leads to the fact that doctors see it appropriate to examine both departments to determine the cause of pain and limit the mobility of the spine in the lower back area, so the procedure is in most cases called the MRI of the lumbosacral section.

Usually, a spine examination is required if the patient complains of back pain closer to the waist, which interfere with the change in the position of the trunk. After the patient tells about the symptoms, the doctor already has suspicions about possible pathological processes in the body that cause the appearance of the described clinical picture. With a certain degree of accuracy, the diagnosis can be confirmed by a blood test or a puncture of the spinal cord, but put the final diagnosis, delineate the lesion area, see which processes led to the disease and develop a further scheme for solving the problem can only help specialized instrumental studies, one of which is MRI lumbar spine.

Indications for an MRI study include:

• suspicion of any pathology and  trauma of the spine,
• suspicion of tumor processes in the lumbar region,
• suspected anomalies in the development of other parts of the spine, for example, cervical or thoracic,
• control of the recovery period after removal of the  intervertebral hernia,
• the detection of the pathway of metastasis after removal of the tumor in the lumbar or sacral department,
• impaired mobility of extremities in the sacral region,
• pain in the legs  and   back pain of  unknown etiology,
• preparation for the forthcoming operation in the lumbar region and control in the postoperative period,
• diagnosis of multiple sclerosis  and determining the degree of its progression,
• suspicion of syringomyelia - a pathology characterized by the formation of cavities inside the spinal cord,
• revealing the causes of circulatory disorders in the lower extremities (risk factors for such disorders may be traumas, inflammatory and degenerative processes in the vertebrae, which cause blood vessels to clump).

As for diseases of the spine, in addition to injuries (fracture or severe bruise of the spinal column, its instability), doctors also consider the following pathological processes:

• inflammatory processes in the spinal cord ( myelitis ),
• infectious inflammation of bone tissue ( osteomyelitis ),
• decreased density of the spine bones ( osteoporosis ),
• the appearance of spine-shaped outgrowths along the edges of the vertebrae and their proliferation, disrupting the mobility of the spine and leading to narrowing of its canal ( spondylosis ),
• degeneration of the cartilaginous tissue of the spine ( osteochondrosis of the lumbar spine, which is a very common disease in which the MRI has more information, allowing the doctor to determine the extent of the lesion and make predictions of the disease)
• damage to the cartilaginous tissue of the joints with the involvement of soft tissues, tendons and bones ( osteoarthritis ) in the process ,
• displacement of vertebrae ( spondylolisthesis ),
• pathology of intervertebral discs (their displacement, hernia, protrusions, chronic pain syndrome in the spine or dorsopathy, inflammation and fusion of the intervertebral joints or  Bekhterev's disease ),
• the presence of transitional vertebrae on the border of the lumbar and sacral divisions (if they are asymmetric, there is instability of the spine, lumbar scoliosis develops, etc.)
• stenosis or narrowing of the spine, which is a consequence of long-lasting inflammatory-degenerative processes in the spine
• formation to the esta in the coccyx.

Very valuable information MRI gives when suspicion of  tumor processes. The study not only helps to identify the presence of a tumor, but also accurately determine its location, size, structure and the presence of metastases in other organs. The procedure can be prescribed even if the tumor was located in other departments, but there is a suspicion that its metastases penetrated the lumbar spine. MRI allows you to monitor the quality of the metastasis removal process.

In the diagnosis of intervertebral hernia and instability of the spine in the areas of transitional vertebrae, it is very indicative to carry out MRI with verticalization. This study involves studying the state of the spine in the supine and sitting position, when the tomograph table and the magnet rise to the vertical position. In this case, the spine begins to experience a noticeable axial load, and the defects become more pronounced.

[1], [2]

Preparation

MRI of the lumbar spine is one of the diagnostic studies that does not require special preparation for the procedure. The patient will not have to revise his daily regimen and dietary preferences or worry about taking medications. The scanner's indications will not depend on what the person ate on the eve of the research or when he visited the toilet. This is one of the advantages of the MRI method.

The procedure does not have to bring your own bedding or special clothes. Disposable household items are given to the patient at the clinic where the examination is being conducted. The patient will also be asked to remove any items containing metal parts (watches, rings, earrings, bracelets, piercings, etc.) that can interact with the magnetic field, introducing unwanted changes and threatening to burn tissues.

If on the previous day the patient did not tell the doctor about the available metal objects inside the body (dentures, pacemakers, implants, artificial joints or heart valves, IUDs, etc., including shell and bullet fragments), it's time to say this now with the material possibility), from which the implant or prosthesis is made. Any large metal implants and debris, as well as electronic devices and implants made of ferromagnetic materials that can not be removed, will be an obstacle to MRI.

You can not take keys, payment cards, mobile phones and other electronic devices with you to the procedure. They can be left with relatives.

The tomograph is a large device in the form of a torus with a retractable table. Some people, for example, those who suffer from claustrophobia, can be frightened of the moment when the table on which they lie, enters the cavity of the apparatus or is there for a long time. If such a fear is present, it is necessary to tell the doctor about it, who will take care of the patient's soothing remedy beforehand.

In principle, on this preparation for the procedure of research on the scanner and ends. But this is only if the MRI is performed without the introduction of contrast. The introduction of contrasting chemicals in the body implies special care.

The patient will have to pass blood and urine tests, pass a test for allergic reactions. Gadolinium and iron oxide used for MRI are not so powerful allergens as contrasts for computed tomography, and yet it is better to be safe to not harm a person. The urine test will show the state of the kidneys, which are primarily affected by drugs, and blood tests can confirm or reject the presence of hemolytic anemia, in which the red blood cells are destroyed (the magnetic field can enhance this process).

If, during an MRI without contrast, the patient can take food right up to the beginning of the procedure, then the introduction of contrast requires the refusal of food and medication at least 3-4 hours before the start of the examination. This will help to avoid unpleasant consequences in the form of nausea and vomiting.

What should I take with me for the MRI of the lumbar spine with or without contrast? There is no compulsory list, but it is recommended that you have personal identification documents, an outpatient card, the results of previous studies of the spine (if any), the results of the tests, the direction of the doctor. But even if all these documents are not available to the person, this is not an excuse for refusing to carry out MRI diagnostics.

[3], [4]

Technique of the mRI of the lower back

After a person is ready to conduct a survey, he is put on special disposable clothing, and placed on a tomograph table. The doctor will ask you not to move during the scan, as any movement may distort the overall picture of the study. If a person experiences difficulties with prolonged stay in a static position, which often happens with young children or with severe pain in the spine, his body will be fixed with special straps. Alternatively, it is possible to administer intravenous anesthesia or take pain medication, which does not affect the truth of the results.

The patient is warned in advance that during the procedure he will be in the office where the scanner is located, one (although, in some cases, the presence of relatives or staff of the clinic is allowed). The doctor and, if necessary, the patient's relatives will be in the other room at this time, in which there is an opportunity to observe what is happening. That is, the doctor will monitor the patient's condition remotely. In addition to remote visual contact, there is the possibility of two-way voice communication. The microphone is installed in the tomograph, and the patient has the opportunity to call for help or report unpleasant sensations during the procedure. Being in another room, the subject hears all the doctor's instructions about the correct behavior during the procedure.

A working device produces a monotonous rumble that can frighten or irritate patients, so the examinees are given special vacuum headphones that help to feel more comfortable.

The table, on which the examinee is laid, moves inside the scanner until the part of the body to be scanned is inside the device. After that, a magnetic field is turned on, which is many times larger than the Earth's magnetic field, and the apparatus starts scanning the affected area.

When asked how long the MRI of the lumbar spine lasts, the answer is ambiguous. In most cases, everything is limited to 15-20 minutes, but in some cases, the diagnosis can be delayed even by 30-40 minutes, depending on the complexity of the pathology. If contrast is entered, the duration of the procedure will be somewhat greater than the MRI without contrast.

MRI of the lumbar spine is usually done in two projections: axial (transverse) and sagittal (vertical). During the whole procedure, the device, a magnet inside of which wraps around the area under investigation several times (as laid down in the manual), makes a series of images that allow you to restore a full three-dimensional image of the investigated area on the computer screen.

Contraindications to the procedure

Magnetic resonance imaging is one of the safest diagnostic procedures, but this does not mean that this method has no contraindications. However, the limitations of the diagnostic study are related not so much to the pathologies present in the body as to the metals previously implanted in the patient's body.

Absolute contraindications to the MRI of the lumbar spine without contrast is not so much. The procedure is not carried out in patients in whose body there are ferromagnetic implants or metals that are able to interact with a magnetic field or can cause tissue burns and electronic devices supporting the life of the patient (the magnetic field can have a bad effect on the pacemakers and other similar devices) . Ferromagnetic components can have artificial middle ear simulators, shell fragments, Ilizarov apparatus and some other implants.

Relative contraindications are the patient's use of an insulin pump, portable electrical stimulators of the nervous system, presence in the body of implants of the middle and inner ear, imitators of the heart valves, blood clamps, dental implants and braces from metals that are not related to ferromagnets. Some precautions will have to be taken by conducting a procedure for patients with heart failure in the stage of decompensation, with claustrophobia and inadequate behavior of the patient (in this case, drug-induced sleep is recommended).

It is not advisable to carry out the procedure of magnetic resonance imaging for patients in very serious condition, as well as for pregnant women in the early stages, but if urgent diagnosis of the pathology of the MRI of the lumbar spine is necessary, even in such patients, and it is considered preferable to the popular x-ray or computer tomogram.

An obstacle to MRI is the presence of tattoos, for which titanium compounds were used. In this case, there is a risk of tissue burns.

Tomographs used for MRI diagnosis can have a closed or open contour. The device with an open circuit allows you to undergo procedure for patients with relative contraindications.

If it is a question of MRI with contrasting, then it is not carried out to diagnose spinal pathologies in pregnant women at any time (contrast agents may affect fetal development), in patients with hemolytic anemia and severe renal function deficiency (the half-life of the chemical and, accordingly, its negative impact on the body). Accordingly, contrasting is unacceptable in patients with allergic reactions to the drug administered.

[5]

Normal performance

Decoding of the results of MRI of the lumbosacral spine is carried out after the end of the procedure. Although in some clinics there is an opportunity to conduct a tomography with visualization, and already along the way to draw some conclusions about the condition of the spine and surrounding tissues.

For some, the MRI procedure will seem too long in time (if compared with a conventional X-ray), but this is necessary to obtain a three-dimensional image consisting of a set of individual flat images made in 0.5-5 mm increments. Even longer will have to wait for the results of the research. Most often, they take about 60 minutes to decode them, but in the case of multiple or complex fractures, as well as in the presence of tumor processes, the results can be obtained even the next day.

What does the MRI of the lumbosacral spine show? On the image obtained with the help of a magnetic resonance imaging the doctor can see:

• curvature of the spinal column in the lumbosacral region,
• inflammatory processes in various tissues (cartilage, muscle, nerves, etc.),
• degenerative changes in bone-cartilaginous tissue (compaction or thinning of cartilage, destruction of bone density, appearance of growths, reduction of spacing between vertebrae, etc.),
• tumors and other neoplasms in the lumbosacral area, which in the MRI picture look like a darker spot in a round shape compared to other tissues,
• metastases of tumors in the form of clearly delineated objects of different shapes, surrounded by swollen tissues,
• displacement of the vertebrae relative to the axis,
• disorders of blood flow through the vessels of the pelvic region and lower limbs,
• presence of voids in the spinal cord.

MRI allows not only to visualize the pathology, but also to assess the degree of lesion of the spine and adjacent structures, because changes in the structure and position of the bone structures of the spinal column often lead to circulatory disorders and the appearance of neurologic symptoms due to pinching of nerve fibers.

Hence the pain syndrome with which patients come to the therapist, traumatologist or orthopedist. A person can see a doctor complaining of pain, weakness and loss of sensitivity in the legs, and a MRI of the lumbar region will reveal the cause of these symptoms in changes in the structure of the spine in the region of the waist and sacrum.

[6], [7], [8]

Complications after the procedure

MRI of the lumbar spine is considered a safe procedure, which has neither close, nor long-term consequences. It is clear that we are talking about conducting diagnostics taking into account absolute and relative contraindications, as well as requirements for quality scanning.

As for the unpleasant sensations during the study, they are practically absent. Some patients may feel minor twitching in the muscles of the body or a slight tingling, which is a variant of the norm and should not frighten the researcher.

When MRI is performed with contrast and requires the introduction of chemicals into the body, patients after the procedure may experience headaches, nausea, or vomiting that are associated with the action of "chemistry" rather than the magnetic field. If we are not talking about the  hypersensitivity of the body to chemotherapy drugs, these symptoms pass fairly quickly and have no consequences. To reduce the severity of such unpleasant consequences, a test for sensitivity to contrasts is preliminarily conducted and a requirement is not to eat for 1.5-2 hours before the procedure.

If the body has tattoos in the area of the body exposed to a strong magnetic field, the patient may experience a burning sensation that is a consequence of tissue burns.

MRI devices do not use ionizing radiation, which can cause various complications after the procedure. But the magnetic field can affect the work of implanted in the body of electronic devices and attract prosthesis from ferromagnetic alloys, so you should not take risks. The physician should be aware of the possible risks to the same extent as the patient who is warned about the consequences before the procedure.

Be that as it may, there is a constant connection between the tomograph scanned on the table and the doctor performing the procedure, and the person has the opportunity to report any unpleasant sensations that require the device to stop and medical care.

[9], [10], [11], [12]

Care after the procedure

MRI of the lumbar spine is a non-invasive and painless study, therefore no withdrawal is required after the procedure. Immediately after the end of the diagnostic examination, the patient can be sent home. But since the diagnosis is carried out purposefully, usually its results indicate a pathology that requires appropriate treatment. That is, after the magnetic resonance imaging and obtaining its results, the patient will have to visit some more specialists (traumatologist, surgeon, phlebologist, neurologist, etc.) who, after studying the information of MRI, will develop an effective treatment regimen for the detected disease.

[13], [14], [15]