Everything you want to know about ultrasound is sorted out
1. Is ultrasound harmful to the human body?
Ultrasound diagnostic machines work in a similar way to bat predation: they send out ultrasound waves that are processed and get useful information.
Ultrasound is a frequency of more than 20 thousand Hertz of sound waves, it is not radioactive, safe for human body, harmless, its use is very wide, almost involved in various industries. Medical ultrasound diagnosis is widely used, which can not only diagnose but also use its principle to achieve the purpose of treating some diseases. At ordinary times, we are most often exposed to the ultrasound examination of routine abdominal organs such as liver, gallbladder, pancreas and spleen; Obstetrics and gynecology ultrasound examination such as female uterine appendages maternal examination; Urogenital system ultrasound examination such as kidney, ureter, bladder, etc. Superficial organs such as thyroid gland, breast, superficial small masses; In addition, there are vascular and cardiac ultrasound examination. In addition to the above more routine examinations, ultrasound can also be used in brain, eye, skeletal muscle, angiography, interventional therapy, etc. Different ultrasonic probes with different frequencies and different focusing methods can be used to examine different organs. The most commonly used probes are abdominal low-frequency convex array probes, superficial high-frequency linear array probes, cardiac ultrasonic phased array probes, and intracavitary probes.
2. What is the fluid applied during the examination? Is it harmful to human body?
The coupler is applied before the examination, which is a water-soluble liquid, colorless transparent glue, and non-toxic to the human body. It can be wiped or cleaned with warm water after the examination. The purpose of applying the coupler is to make a good contact between the probe and the skin, which is conducive to the transmission of ultrasound, improve the imaging quality, and make the image clearer.
3. Color Doppler = color TV?
"Doctor, why are there no color images on the instrument screen? Are you color Doppler ultrasound?" I believe that every patient has raised similar questions. With the continuous development of medical conditions, most of the patients are examined by color ultrasound. But why is the screen doctors are looking at so different from the color TV at home? The meaning of the word "color" in color Doppler ultrasound is generally said to indicate the direction of blood flow of blood vessels, generally red and blue. Doctors determine whether there is blood supply to the target organ and the direction of blood flow to assist in the diagnosis of diseases. So, color ultrasound is color, but not equivalent to your home color TV.
4. Why is fasting required for ultrasound?
Ultrasound diagnosis has a high resolution of the tissue structure, but in the solid-gas or liquid-gas interface with large contrast, ultrasound is difficult to penetrate, almost total reflection. If, after eating some gas can be as the swallow food, make the intestinal gas increases, some foods such as soy products themselves are prone to gas, when undergoing abdominal ultrasound, limits the sound waves penetrate, image display is not clear, and gastrointestinal tract after being filled with food, food will form and lumps, stone the same audio-visual, lead to misdiagnosis. So in undergoing abdominal viscera, such as liver, gallbladder, pancreas, spleen, kidney, stomach, abdominal cavity and retroperitoneal vessels and intestinal inspection need to fasting, six to eight hours, the warm water to drink here, do not eat milk, bread, eggs, noodles, colored beverages, which can reduce interference of gastrointestinal tract chyme and gas filled ensure the bile in the gallbladder, and improve the quality of imaging. After eating, the contraction of the gallbladder becomes smaller, which is difficult to distinguish between physiological and pathological changes, and also affects the display of lesions in the gallbladder, such as gallstones and polypoid lesions. In addition, for patients with frequent abdominal distension, it is recommended to have a light diet the night before the examination, and can take appropriate drugs to promote the digestive tract before the examination.
5. Why do some ultrasound examinations need to hold back urine?
In the examination of bladder, ureter, prostate and seminal vesicle gland, unmarried women with more vaginal bleeding, ultrasound examination of pregnant women 3 months before pregnancy, need to hold in urine. The purpose of holding back urine is to fill the bladder to reduce the interference of intestinal gas and provide a good sound through window for examination. During gynecological examination, the bladder urine volume is generally required to be 300-400ml, and the sign of good bladder filling is the supine position, the lower abdomen is slightly convex, and the probe can be pressed down and can tolerate pressure.
6. Why do the same gynecological ultrasound, I want to suppress urine, she does not need to suppress urine?
With the advancement of technology and the diversity of probes, two kinds of probes can be used in gynecological examination, that is, transabdominal ultrasound and transvaginal ultrasound. The population is different: transabdominal ultrasound is suitable for all women, including pregnant women; Transvaginal ultrasound is indicated for married women with suspected placenta previa.
Advantages of transvaginal ultrasound:
① The frequency of the probe is higher than that of the conventional abdominal probe, and the resolution is significantly improved, and the pelvic organs and small lesions are more clearly displayed.
② No need to hold in urine, reduce the pain of holding in urine.
③ In obese patients, vaginal ultrasound examination does not need to go through the abdominal multi-layer tissue and thick fat, the interference is significantly reduced, and the image is clearer.
Disadvantages of transvaginal ultrasound:
The probe frequency is high and the penetrating power is limited, and the visualization of higher located organs and larger lesions is limited. For example, when the cervix is elongated after cesarean section, the higher position of the uterus, the higher position of the ovary, the large uterine fibroids or multiple fibroids, the large mass in the pelvic cavity, or the mass with a long pedicle and a high position, transvaginal ultrasound can not show the whole picture, and it needs to be combined with transabdominal ultrasound to give a more accurate diagnosis. Not all women are candidates for vaginal ultrasound. There are contraindications.
7. Stomach discomfort do not want to do colonoscopy, can also do gastric ultrasound?
This year, with the development of science and technology, the ordos city Chinese medicine hospital ultrasound in gastric ultrasound imaging examination, for gastritis, the stomach cancer (exogenous submucosal tumors, tumor), gastric ulcer, gastric polyps, gastroptosis, gastric motility and gastric varices and duodenum ball ulcer disease diagnosis have relatively rich clinical experience. Contrast-enhanced ultrasonography (CEUS) is a mature technology with a simple procedure and oral imaging aid under the guidance of a physician before fasting. It has high diagnostic value for gastric diseases, especially gastric tumors, ulcers, etc., and the examination is flexible, convenient, noninvasive, painless, low cost, and has the advantages of real-time dynamic and repeatability, which can make up for the shortcomings of traditional examination methods.
