Use and maintenance of rigid endoscopes

Rigid endoscopes are used in clinical medicine. They have the characteristics of small trauma, convenient operation, clear images, and wide application range. They have been widely used in hepatobiliary surgery, urology, thoracic surgery, orthopedics, gynecology, ENT, etc. Because the rigid endoscope is a relatively delicate optical instrument, high requirements are put forward for its use and maintenance. Correct use and maintenance will greatly extend the service life of the rigid endoscope.

The basic structure of a rigid endoscope is composed of three parts: a working lens tube, an eyepiece, and a light source interface. The working lens tube consists of four parts: the outer lens tube, the inner lens tube, the optical lens, and the optical fiber. The structural characteristics and slender shape of the working mirror tube make it the most vulnerable to damage. The outer mirror tube is made of thin-walled steel pipe, which will deform when subjected to greater external forces. Optical lenses are composed of many columnar lenses. An optical system is formed in the inner lens tube. When the outer lens tube is deformed, the optical system will be directly affected, resulting in blurred vision and blackened edges. The optical fiber is responsible for the transmission of lighting light between the inner and outer lens tubes. It is made of very fine optical glass. An endoscope needs to install more than a thousand or even thousands of optical guide fibers. When the outer lens tube is deformed or vibrates strongly, it will cause part of the optical fiber to break. The more it breaks, the darker the light becomes.

Rigid endoscopes are more sensitive to external forces, but during use, as long as they are operated properly, their durability can still reassure users. We need to pay special attention to the following points：

1. When using other instruments under the observation of the endoscope, especially pliers and scissors with large occlusal force, care should be taken not to extend the front end of the lens tube into the occlusal area of the instrument to avoid accidental injury to the lens tube. When operating, pay attention to exposing all the occlusal mouths of the instrument to the observation range of the speculum.

2. Some endoscopes are used in the sheath tube. When replacing the endoscope or inserting the instrument, care should be taken to move lightly and not to use too much force. During the insertion and unplugging process, when encountering resistance, you should carefully find the cause and do not use brute force.

3. When the endoscope is used with lasers, high-frequency electric knives, microwaves and other photoelectric equipment for surgery, attention should be paid to the distance between the front end of the endoscope and the cutting point to ensure that the front end of the endoscope is not electrocuted or cauterized.

4. When the endoscope cooperates with the endoscope to remove the diseased tissue, care should be taken to control the rotating part of the cutter head to always be within the observation range of the endoscope. When the surgical rotary incision range is large, the rotation of the cutter head should be stopped first, then the endoscope should be moved, and then the cutter head should be moved to the appropriate part under the observation of the endoscope before the rotary incision.

In terms of maintenance, the rigid endoscope should be rinsed after use, and the water stains should be dried out. When there are stains on the front end of the lens, gently wipe with lens paper, cotton swabs or fine gauze. The storage of endoscopes should be kept by a dedicated counter, and soft sponge or polyurethane foam should be padded in the storage cabinet or packaging box. All endoscopes and surgical instruments must be neatly packed and must not be placed in cross-overlap. When taking out or putting in a rigid endoscope, hold your hands flat and take it lightly. There should be desiccant in the storage cabinet or packaging box.

It should also be noted that some hard tube endoscopes are not resistant to high temperature and high pressure. This is mainly because the epoxy resin glue used for the encapsulation of the lens end will open under high temperature and high pressure, causing water to enter the lens tube, and the optical system will produce blurred vision after water enters. Therefore, this type of endoscope cannot be sterilized by high temperature and high pressure. The conventional disinfection method is soaking or fumigation.