1-21. ADDITIONAL EQUIPMENT
a. Endoscopy.
(1) General. Endoscopy is a visual examination of the interior of the body
cavity, hollow organ, or structure with an endoscope, an instrument designed for direct
visual inspection. The endoscope usually is inserted into a natural body orifice, that is,
the mouth, anus, or urethra. It may be inserted through a small skin incision and/or
trocar puncture, as through the abdominal or vaginal wall. An endoscopic procedure is
designated by the anatomic structure to be visualized.
(2) Light source. Illumination within the body cavity is essential for visual
acuity. The light source may be through a fiber-optic bundle or from an incandescent
light bulb.
(a) Fiber-optic lighting. This is an improved lighting system that
illuminates body cavities, including those that cannot be seen with other light sources.
Light is conducted through a bundle of thousands of coated glass fibers encased in a
plastic sheath. Electric current must be transmitted to the light source connected to the
fiber-optic bundle. With fiber-optic lighting, the electric current is entirely external to the
patient.
(b) Bulbs screw into the fitting either at the end of a removable light
carrier or at the end of the built-in lens system. Electric current is conducted through a
single-filament wire to illuminate the tiny incandescent light bulb. A battery box with one
or more sets of dry-cell batteries may be used as the power source for light bulbs.
Fiber-optic lighting has replaced bulbs in most endoscopes.
(3) Accessories. Accessories such as suction tubes, snares, biopsy
forceps, grasping forceps, electrosurgical tips, sponge carriers, and so forth, are used in
conjunction with endoscopes. These can be passed through channels in the
endoscope to remove fluid or tissue, coagulated bleeding vessels, inject fluid or gas to
distend cavities, and so forth. Lensed scopes may be equipped with a still or motion
picture camera so organs or lesions can be photographed during the procedure. Some
rigid scopes have an obturator, a blunt-tipped rod placed through the lumen of the
scope, to permit smooth insertion of the instrument as into the anus. The accessories
that will be needed will be determined by the type of endoscope and the purpose of the
procedure.
b. Electrosurgical Apparatus. The electrosurgical apparatus (unit) is an
electrical machine that has a very high frequency of alternating current. Figure 1-26
shows an electrosurgical apparatus. The surgeon may use the electrosurgical
apparatus to do the following procedures: cut body tissue, stop bleeding from small
blood vessels (coagulation), destroy abnormal growths such as a wart (fulguration), and
sear or dry tissue (desiccation).
MD0923
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