How to choose between electronic endoscope and optical endoscope

In the field of medical imaging diagnosis, endoscopy is a commonly used inspection tool for observing the internal organs of the human body. Among them, electronic endoscopes and optical endoscopes are two common types. They have significant differences in principles, imaging effects, and application scope. This article will delve into the differences between electronic endoscopes and optical endoscopes to provide readers with a more comprehensive understanding.
Principles and working methods
Optical endoscope: Optical endoscope transmits the image of the object to the observer's eyes or camera equipment through optical lenses, and its imaging principle is similar to a magnifying glass. Doctors observe the organs or tissues reached by the lens through direct observation or camera equipment for diagnosis and treatment.

Electronic endoscope: Electronic endoscope uses camera equipment and electronic sensors to convert images of intracavity organs or tissues into electronic signals, and transmits them to the display through cables or wirelessly to achieve real-time digital imaging. Doctors observe images through the monitor and can adjust the magnification and contrast to achieve more accurate diagnosis.

Observation method: The operating part of the optical endoscope is equipped with an eyepiece. The operator must observe the image through the eyepiece. Although a TV camera can be connected to the eyepiece part and the image is displayed on the fluorescent screen through the TV system, the image is far less clear than that of the electronic endoscope. . Electronic endoscopy uses a high-performance TV monitor to display clear and undistorted color images, which can be viewed by multiple people at the same time, which is conducive to teaching and consultation. It is conducive to the communication between assistants and operators during various endoscopic treatments. work close with. In addition, because the surgeon uses both eyes to view the clear images on the high-performance monitor, it can avoid the visual fatigue caused by the monocular observation eyepiece and the adverse effects on the eyes caused by long-term strong light stimulation.

Insertion performance: The quality of insertion performance is related to factors such as the shape, thickness, softness of the endoscope, and the length of the hard part at the top of the endoscope. The top device of the electronic endoscope has a size of 3, which occupies a certain volume. The size of the 3 must be reduced, otherwise the length of the hard part at the top of the endoscope will be increased and the insertion performance of the electronic endoscope will be reduced. In the early products, the hard part at the top of the endoscope was too long, and the insertion performance was not as good as similar models of optical endoscopes. However, new products in recent years have overcome the above shortcomings, and their insertion performance is exactly the same as that of similar models of optical endoscopes.

Optical properties

Viewing angle: In early products, the viewing angle was relatively small, ranging from 75o to 105o. In recent products, the viewing angle has been expanded to 120°, and the depth of field range is 3-100mm, which has exactly the same optical performance as similar optical gastroscopes.
Reproducibility of color tone: The factors that affect the image pigment of fiber endoscope are the objective lens, optical fiber and eyepiece. Among them, the hanging optical fiber has the greatest influence. An optical fiber with a length of more than 1m may absorb light of a certain wavelength and affect the internal image. tone. The factors that affect electronic endoscopes are the characteristics of CCD, video processor and monitor. Compared with optical endoscopes, the factors that affect electronic endoscopes are more and complex. Kenzo Mitsuzane once used a TV color analyzer and various color standards to measure the color tone reproducibility of the Olympus GIF-Q100 electronic endoscope and the GIF-Q10 optical endoscope. The measurement results showed that the color tone reproducibility of the electronic endoscope was excellent. in optical endoscopy.

Diagnostic ability of microscopic lesions: Tatsuo Katsube conducted optical endoscopy and electronic endoscopy on 45 patients with various gastric diseases before surgery, and compared the examination results with surgical pathology. He concluded that electronic gastroscopy can detect microscopic lesions. The diagnostic ability of lesions is better than that of optical endoscopy. It is easier for him to identify the exposed blood vessels of gastric ulcer bleeding and the characteristics of the surrounding regenerated epithelium, and it is easier to make a differential diagnosis between flat and raised atypical epithelium and type IIa early gastric cancer. In addition, because the image of electronic endoscopy is clear and has a certain magnification effect, it can display subtle color changes and other character changes on the mucosal surface, thus improving the detection of micro-type II b and II c early gastric cancer to a certain extent. Rate. Satake Yiji believes that electronic colonoscopy has improved the detection rate of small colon polyps (diameter <0.5cm>).

Performance of saving images: Optical endoscopes can only record and save the images transmitted by optical fibers through photography. The method is monotonous and the images are not clear enough. Because electronic endoscopes use CCDs to convert optical signals into electrical signals, images can be recorded and saved in a variety of ways after being processed by a video processor. ①Use a tape video recorder to record the clear image of the electronic endoscope and save the dynamic image; ②After "freezing" the electronically constructed image, use a 35mm camera to record the still image; ③Use the laser disc to record both dynamic images and It can record incoming images, and the maximum recording capacity of still images is 24,000 frames; ④ It can record 50 frames of still images using soft plastic disks. Electronic endoscopy can also be connected to an electronic computer, and the patient's name, gender, age, main symptoms, diagnosis results and other clinical data and various recorded images can be input into the computer. When it is necessary to follow up the patient or conduct statistics on a large number of cases, When researching, you can search for various information at any time.

Durability: Fiberoptic endoscopes have tens of thousands of fine glass fibers that transmit images. As the number of uses increases, the glass fiber will gradually break, and the black electricity in the field of vision will gradually increase, making it dim and unclear. Electronic endoscopes are guided by CCDs and do not have the defects of glass fiber ends and being easily damaged by X-rays. Therefore, the durability of electronic endoscopes is due to optical fiber endoscopes.

In general, electronic endoscopes and optical endoscopes have their own advantages in the field of medical imaging diagnosis, and their differences are mainly reflected in imaging principles, imaging effects, and application scope. With the continuous advancement of science and technology and the continuous innovation of medical technology, both technologies will play an important role in different scenarios, providing diversified choices and more accurate services for medical imaging diagnosis.