MRI liver with contrast: preparing the results
An established fact is the poor prognosis of malignant liver tumors, which are detected at the stage of clinical manifestations. Usually by this time the tumor has already spread to the surrounding tissue and organs. MRI of the liver with contrast shows a tumor in the early stages of development and enables to take appropriate measures, which are often unable to completely stop the disease.
The method is based on the physical phenomenon of nuclear magnetic resonance. By registering the response of different fabrics, placed in a constant magnetic field of high frequency, on the screen of the imager at a picture of the internal organs and pathological processes in them.
How is it MRI?
MRI is performed using a special apparatus – magnetic resonance imaging. The device is equipped with a couch, on which is placed the patient, then it is placed inside the capsule, which creates a high frequency electromagnetic field.
By making consistent slices (snapshots of the authority in increments of five millimeters), the device shows detailed images similar to x-ray, in the horizontal and vertical (sagittal) planes.
During the procedure the patient is asked to remain stationary. The lead time of the study takes about thirty to forty minutes.
Before you put the patient inside the machine it is carried out by intravenous injection of a contrast agent.
Currently in use as a contrast agent based on gadolinium. Gadolinium is a rare earth element of the lanthanides. By itself, the gadolinium – toxic substance, but it hiltie compounds that are used in contrasting preparations, inert and excreted unchanged by the kidneys. The most common drugs are Magnevist, OmniScan, Primovist, but there are many other drugs.
The effectiveness of contrast agents based on the ability to spread through the vessels, which shows the detailed structure of the liver and pathological processes.
Depending on the chosen method of a contrast agent bolus can be injected (intravenously, the dose) or by using infusion pump (drip infusion at a given rate). The necessary volume of contrast is calculated according to the formula, depending on the patient’s weight.
After the procedure, contrast medium is excreted entirely unchanged by the kidneys. During the first day the body leaves 95% of the substance.
What needs to be done before the procedure?
Preparation for the MRI study is quite simple and requires no special procedures. The day before the test do not eat foods that increase gas formation in the intestine. These include bread, vegetables, dairy products. The day before the examination can not eat or drink for five to six hours before the procedure.
Categorically prohibited the execution of the study in the presence of metal objects. Before entering the room where the MRI machine is located, you must remove all metal objects (earrings, necklaces, belts, watches, hair clips and so on), and leave in the dressing room, clothes, phone, keys, credit cards. In some health facilities, patients wear disposable clothes.
If the body is own clothes, do not forget that the metal parts may be underwear, for example, bone or bra metal decoration (charms) on clothes.
Preparations for MRI with contrast includes a test for hypersensitivity (allergic reaction) to gadolinium and other components of the drug. Typically, this procedure involves applying the product to the skin of the back of the wrist. After a few hours results evaluation: if the skin there are no changes then to conduct the research.
Such training may not be conducted if the patient has previously performed the procedure is an MRI with contrast and it was successful.
Indications for MRI of liver with contrast
- Identification and differentiation of tumors and metastases in the liver.
- The condition of the blood vessels of the body.
- Confirmation of diffuse changes of a liver (hemachromatosis, steatosis, cirrhosis, hemosiderosis).
- The assessment of the liver prior to transplantation.
- Assessment of treatment of oncological processes.
- Detection of congenital organ defects.
Contraindications to MRI with contrast
- The presence of metallic and electronic prostheses and implants in the human body. The exceptions are titanium elements that do not respond to the magnetic field.
- The Apparatus Elizarova.
- Metal clips on blood vessels of the brain.
- Prosthesis to the inner ear.
- Tattoos with a suspension of iron and even with the titanium particles.
- Early pregnancy (first trimester).
- The weight of the patient more than a hundred thirty kilograms (limited by size of scanner).
- Mental illness.
- Other causes in which the patient cannot remain motionless throughout the study.
- Allergic reactions and hypersensitivity to gadolinium and other components of the contrast agent.
- A significant decrease in glomerular filtration rate of the kidney (complicates the derivation of gadolinium).
- Distinct forms of claustrophobia.
Before you put the patient in the apparatus, the MRI doctor be sure to find out all possible contraindications.
MRI is a leader in the diagnosis pathology of many organs and systems, with distinct advantages over other methods: it is virtually harmless and allows to carry out the procedure for pregnant women and young children.
Also a plus is the ability to repeatedly execute a procedure within a short time period, as it does not bear radial load.
The negative aspects include the relative duration of the study, its cost, and restrictions on contraindications. Other disadvantages of the study not.