The liver is the parenchymal organ and the largest gland in the body. Diagnosis of liver diseases requires the use of both laboratory and instrumental examination methods. One of the most informative methods is ultrasound of the liver. Norm, interpretation of indicators are the subject of this article.
The structure and structure of the liver
The liver is the largest laboratory of the human body, where the processing and synthesis of a large number of substances occurs. It consists of 4 parts. The two largest - the right and left, are the largest and are well visualized on ultrasound. The other two are square and tailed, much smaller and do not have significant diagnostic value during the examination. Externally, the liver is covered with a glisson capsule, which reacts with an increase in the size of the gland.
The functional and structural unit is the hepatic lobule, which consists of several hepatocytes, small veins, arteries and excretory bile duct. Hepatocyte is a specialized cell in which synthetic and metabolic processes occur.
Vascular system of the liver
Blood supply to the liver is provided by the hepatic arteries. The outflow of blood provides a portal vein, which is a large reservoir that collects blood from unpaired organs of the abdominal cavity. The liver filters this blood mass and throws it into the inferior vena cava. To the greatest extent, the liver synthesizes bile, which flows through the small bile capillaries into the right and left common hepatic ducts, and then through the common bile duct into the duodenum. Ultrasound of the liver allows you to fully explore and study the structure of these formations. Norm, decoding of the examination allow differential diagnosis with other diseases of the gland and surrounding organs.
Liver function
One of the most important is the detoxification function. The unique structure of the hepatic lobule and the structure of the venous system, which forms sinusoids, ensures the delay and neutralization of metabolic products and unoxidized compounds in the parenchyma of the gland, followed by the conclusion of the latter. The excretory role of the liver lies in the synthesis of bile, which is a solution of bile and fatty acids and some trace elements. The synthetic function of the gland is the formation of almost all protein fractions of the blood and some specific substances (lipoproteins, coagulation factors, enzymes).
Bile has a detergent function and stimulates intestinal motility. The digestive role is also provided by bile, which promotes the emulsification of fats and improves the digestion of the latter by pancreatic lipase. The protective role of the largest gland of the body involves the synthesis of protective immunoglobulins and some components of the complement system. In the fetus and newborns, the liver plays the role of hematopoiesis. The size of the liver depends on the proper functioning and functioning of the organ. The norm in an adult is relatively constant and can vary in the range of 1-4 cm.
The essence of ultrasound examination
Ultrasound is a widely available, relatively cheap and painless method for examining internal organs.
Ultrasound has the ability to bounce off internal organs and thus change the wavelength and frequency. These changes are recorded by the sensor of the ultrasound machine and sent to the control unit, where the processing and image formation on the monitor are carried out. In this case, the sensor also acts as a generator of ultrasonic waves.
One of the most accessible organs for examination is the liver. The dimensions of the ultrasound probe and its resolution allow you to examine the organ from different angles and study the homogeneity of its structure. In addition, the largest gland of the body incorporates heterogeneous structures (vessels, bile ducts).
When is an ultrasound examination of the liver
First of all, a visit to an ultrasound examination room should be given to persons undergoing a medical examination. This technique allows you to see some dangerous diseases in the initial stages of development and conduct appropriate treatment. Patients who have been diagnosed with a liver abscess or viral hepatitis by a doctor are required clients of an ultrasound room. Traumatic damage to the abdominal organs, a suspicion of the presence of neoplasms or a change in laboratory tests (especially liver tests) is the basis for ultrasound examination of the liver.
A gynecologist sometimes requires an ultrasound to select the optimal method of hormonal contraception and in almost all malignant neoplasms of a woman’s reproductive system. Patients suffering from alcoholism or already having cirrhosis of the liver should periodically examine this organ on an ultrasound machine. If you periodically notice a cutting pain in the right hypochondrium and lack of appetite, you should also do an ultrasound of the liver. The norm, the interpretation of the result in the vast majority of cases allow you to immediately make the correct diagnosis.
How to prepare for an ultrasound of the liver
The preparatory phase is an important point before the examination. It aims to create conditions for better visualization of abdominal organs, including the liver. The patient should come for an examination on an empty stomach, and the last meal should be at least 8 hours before the study. It is not recommended to consume foods that cause the formation of gases in the intestines (dairy and legumes) a day or two before ultrasound diagnostics. In addition, if a person has such a tendency, then he should take 3-4 tablets of black coal in the evening before the examination. Your doctor may also recommend one or two cleansing enemas.
Ultrasound of the liver: indicators
Before examination, the ultrasound diagnostics doctor applies a special gel to the skin of the abdomen, which improves the contact of the sensor with the skin and ensures the formation of an optimal picture.
First of all, the structure is evaluated. It is normally homogeneous. The edge of the liver should be flat. After that, they begin to measure the size of the right and left lobes of the gland. For them, the thickness and sagittal size are measured. Normally, for the right lobe, the thickness should be 11.2–12.6 cm, and the sagittal size is up to 15 cm. The left lobe is smaller, so its thickness under normal conditions is 7 cm on average, and the sagittal distance is up to 10 cm. An ultrasound machine can easily determine the total size of the liver. The norm in an adult ranges from 14 to 18 cm in length and 20-23 cm in width.
Next, the parenchyma of the gland is analyzed for the presence of nodes, seals and calcifications that form changes in the echo signal. By amplifying or attenuating the ultrasound wave, the doctor can recognize a fluid or dense formation. Sometimes a shadow may form in the middle of the fluid formation, which indicates a parasitic cyst.
Heterogeneous structures include arteries, veins, and bile ducts. The transverse size of the portal vein should not exceed 13 mm, and the inferior vena cava has a diameter of 10 to 15 mm. The hepatic veins that flow into the vena cava have a diameter of 6 to 10 millimeters. The hepatic artery is evaluated in the area of the gate of the liver, where its thickness is from 4 to 7 mm. Through the common bile duct, an outflow of bile occurs. Normally, its diameter should be from 6 to 8 millimeters.
Contraindications for examination
Ultrasound diagnosis in adults has no contraindications. If the patient is not prepared or incorrectly performed the preparations for the examination, his appointment in the ultrasound room should be rescheduled. This will allow to perform a better ultrasound of the liver. Norm, decoding of the result allows you to establish the correct diagnosis and prescribe the appropriate treatment.
Estimated price
If you are periodically bothered by pain in the right hypochondrium, nausea, a feeling of bitterness in the mouth, then an ultrasound of the liver should be performed. The price compared with other instrumental methods is affordable and ranges from 700 to 1400 rubles.