Whether it's going to the hospital for treatment or undergoing a health check-up, doctors always require patients or examinees to undergo ultrasound examination, and many people's understanding of ultrasound examination is limited to pregnant women who need to undergo ultrasound examination. In clinical practice, ultrasound is not limited to the use of pregnant women for fetal examination, but is often used for cardiovascular disease and chest and abdominal examination. In view of this, today we will briefly introduce some small knowledge of ultrasound medicine to you.
1. What is ultrasound examination? How is ultrasound examination used to examine the human body?
The ultrasound commonly mentioned in clinical practice is ultrasound, which belongs to a type of mechanical wave. Our human ears can hear sound frequencies ranging from 20Hz to 20000Hz. If the frequency of sound waves is below 20Hz or above 20000HZ, they will not be heard. So, sound waves with frequencies exceeding 20000HZ are called "ultrasonic waves". The ultrasound frequency commonly used in medical diagnosis work is between 2HZ and 10Hz. It can propagate in the human body and reflect back a part after encountering different tissues. After computer processing, it is displayed in the form of images, curves or waveforms. Doctors responsible for ultrasound examination can diagnose physiological and pathological conditions based on the characteristics of the information obtained.
Does ultrasound examination have any impact on the human body?
When ultrasound propagates in the human body, the functions of the biological system are activated, and its structure or state will change, which is a biological effect. The severity of biological effects varies due to the high or low ultrasound dose and the length of examination time. At present, the ultrasound examination equipment, ultrasound dose, and examination time used in clinical diagnosis work are all controlled within the safety factor, and the impact on the human body can be basically ignored.
What are the advantages of ultrasound examination?
Ultrasound examination is easy and fast to operate, does not cause any pain or damage to the examinee, and the images are clear and intuitive, which has been accepted and recognized by a large number of clinical doctors and patients. Ultrasound examination is similar to X-ray examination CT、 Magnetic resonance imaging and other imaging diagnostic techniques are commonly used in clinical practice, and their advantages and disadvantages can complement each other and improve together.
What are the types of ultrasound examinations?
There are many types of ultrasound examinations, including A-type ultrasound, B-type ultrasound, D-type ultrasound, and M-type ultrasound. The ultrasound examination commonly used in clinical practice in China is a combination of multiple types. A-type and M-type are both one-dimensional imaging, with A-type still being used in ophthalmology and other fields being largely phased out. M-type is commonly used in cardiac ultrasound examination. B-type is currently the basis for all ultrasound examinations and can display two-dimensional spatial images. D-type refers to Doppler ultrasound, which uses Doppler frequency shift signals from blood flow and organ activity, processed by relevant technologies, color coded, or overlaid on B-type two-dimensional images. This is commonly known as color Doppler ultrasound. Ultrasound can provide hemodynamic information and two-dimensional image morphological information, and is currently the mainstream technique for ultrasound examination.
In summary, ultrasound examination also has limitations, such as limited diagnostic efficacy for lung, gastrointestinal, and skeletal lesions. In addition, the ultrasound examination results are obtained by doctors analyzing the images after understanding the patient's medical history and relevant clinical data. The pathological diagnosis results cannot be directly displayed, so in clinical application, comprehensive analysis from multiple aspects is necessary to ensure the correctness of the diagnosis.