Several things you need to know before doing an ultrasound

Ultrasound examination has developed from A-ultrasound, B-ultrasound, and color Doppler ultrasound to today’s contrast-enhanced ultrasound and intracavitary ultrasound. It is closely related to clinical examinations in many departments and is almost used for whole body examinations. It can be said that ultrasound examinations have become An important step in clinical diagnosis is also the eyes of the clinician. Because of its low price, real-time inspection, painless, non-invasive, fast, simple and many other advantages, it is widely used. So, before doing ultrasound, what precautions do we need to know to better improve the accuracy of ultrasound examination and understand our own diseases more accurately?

What is ultrasound
Ultrasound examination is a modern medical diagnosis method that uses ultrasound technology to monitor the structure of human tissues and physiological structures, and make prompts to discover diseases. In a biological system, the propagation of ultrasound can change the state, structure or function of the biological system, that is, the biological effect of ultrasound. The degree of its severity usually depends on the length of the inspection time and the size of the ultrasound dose. Nowadays, the inspection time and ultrasound dose used in clinical diagnosis are within a very safe range and almost negligible. It can be seen that ultrasound diagnosis is a cheap, intuitive and effective, convenient, fast, painless and non-invasive inspection method.

Ultrasound is not harmful to the human body
Compared with imaging examination methods such as magnetic resonance, CT, X-ray, ultrasound is a high-frequency sound wave without electromagnetic radiation and ionizing radiation. In the medical field, the control of ultrasound intensity is within the safety threshold, and the ultrasound inspection method is non-scheduled sliding inspection, and the inspection time is short, so it is a basically safe, non-invasive, and harmless inspection method. In addition, the scope of ultrasound examination mainly covers the diagnosis of diseases in the cardiovascular cavity, obstetrics and gynecology, chest and abdomen, cranium, and superficial organs. Among them, abdominal ultrasound and chest ultrasound are mainly used to diagnose diseases of the genitourinary system, digestive system organs, and thoracic cavity; cardiovascular cavity ultrasound mainly includes hemodynamic examination, deep vein and aortic morphological structure examination. The continuous development of cardiovascular three-dimensional ultrasound, intravascular ultrasound, intraesophageal ultrasound, musculoskeletal ultrasound, and interventional ultrasound has greatly improved the diagnostic accuracy and treatment efficiency.

Matters needing attention before ultrasound examination
Ultrasonic inspection is widely used, low in price, safe and harmless, but it also requires close cooperation to maximize the inspection effect. Therefore, you need to understand the precautions before the inspection.

1. Abdominal ultrasound examination generally includes the large blood vessels in the abdominal cavity, retroperitoneum, pancreas, bile ducts, gallbladder, liver, etc. Before the examination, it is necessary to fast and fast for more than 8 hours. It is usually performed on an empty stomach in the morning. For infants, the fasting time is generally for examination The first 3 hours. On this basis, avoid milk, soy products and other fermentable foods during the first three days of the inspection, and try to consume liquid foods such as porridge on the day before the inspection to prevent gallbladder contraction and gastrointestinal flatulence from affecting the inspection. effect.

2. Ultrasound should be arranged before cholangiography and barium meal (barium contrast of digestive tract). B-ultrasound can be arranged only 2 days after the completion of cholangiography and 3 days after X-ray barium meal and isotope examination. At the same time, taking into account gastrointestinal gas interference factors, even if you have prepared for an empty stomach, under normal circumstances, it is not recommended to do an upper abdominal ultrasound.

3. Taking into account the differences in the patient’s condition, when necessary, the sonographer needs to instruct the patient in detail to make special preparations for some inspection items. The patient needs to prepare other inspection reports and previous cases so that the diagnoser can analyze the patient’s condition more systematically.

4. Patients within 3 months of pregnancy can hold urine moderately under normal circumstances, and do not prepare for holding urine if they are more than 3 months pregnant. In addition, for examination situations that need to know the condition of the placenta, for example, when pregnant women are suspected of having placenta previa, they need to hold their urine for examination.

5. Ultrasound is not recommended for examinations where large areas of skin damage such as trauma and burns, restricted body position, covering by dressings, inadequate exposure of the examined part, and uncooperative patients.

6. If there is no special circumstances such as severe trauma or coma, it is recommended to wear loose clothing to see a doctor. Before the ultrasound examination of neck blood vessels, thyroid gland, etc., necklaces and other accessories need to be removed.

7. Under normal circumstances, the examination items that do not require special preparation are: adult heart, limb blood vessels, breast, thyroid, eye, spleen, kidney, fetal examination in the middle and late pregnancy, etc. In addition, emergency patients do not need special preparation.

8. Transvaginal ultrasound examination of uterine appendages requires pre-defecation. Before transrectal examination of seminal vesicles and prostate, it is necessary to urinate and defecate in advance.

Need to hold back urine
When examining the prostate, bladder, fallopian tubes, ovaries, uterus and other organs, the patient needs to retain bladder urine before the examination, and the bladder must feel swollen before the ultrasound examination. For those undergoing early pregnancy examinations, in order to prevent the uterus from being compressed due to overfilling of the bladder, there is no need to drink water to hold the urine. For example, before the gynecological ultrasound transvaginal examination, it is not necessary to hold the urine.

Reasons why it is recommended to drink plain water to hold back urine before ultrasound examination
The effect of ultrasound examination largely depends on the filling degree of the patient’s bladder, especially in the pelvic and bladder examination items. The more filled the bladder, the higher the accuracy of the examination. Care should be taken to ensure that the bladder is moderate when examining the prostate. Just fill it up. Before the examination, some patients may enter the misunderstanding of holding urine, thinking that it is easier to hold urine by drinking carbonated beverages, coffee or tea. In fact, it is not the case. In the actual examination, if you drink carbonated beverages, coffee, tea to hold your urine, it will often increase the abdominal cavity. The amount of gas can accelerate the peristalsis of the intestines, which will also have a certain adverse effect on the inspection effect. Therefore, when holding the urine, it is recommended to drink plain water about 2 hours before the inspection.