Endoscope

Definition

An endoscope is characterized by its often long, thin (sometimes flexible) lighted tube containing fiber-optical instrumentation attached to a viewing device through which one may closely observe, via the naked eye or an attached camera, the surface of a canal or hollow organ in the body.

Purpose

The endoscope is often used as a form of less invasive monitoring of the body instead of, or in conjunction with, surgery. A key aspect of the device is that it is not only capable of traversing the body to allow direct observation, but may also be equipped with endoscopic accessories that allow manipulation and diagnostic/therapeutic procedures to be performed much less invasively than more conventional surgical operations.

Endoscopic surgery minimizes pain , hospital stays, and recovery time, which is good for patients. Its use is also promoted by health insurance companies and hospital administrators inclined toward reduced costs as well as to offer the best treatment options technology can provide.

Description

The endoscope is a generalization of a broad variety of fiber-optical scopes used to elucidate diverse aspects of the body to medical practitioners for various purposes. Endoscopes come in two main categories: rigid and flexible. The rigid endoscope is designed with a rigid insertion tube and is preferred over flexible endoscopes when feasible because the rigidity allows use of optics that permit greater resolution and the absence of a visible lattice structure. However, it is more difficult to design and construct a rigid endoscope, which entails using lenses rather than fibers to transmit the image externally to the user or to a camera.

The fiber-optical endoscope can in general be viewed as a simple input/output device that utilizes an objective lens system along with a fiber relay and an ocular for magnification. The objective component is inserted directly into the body with a lighting constituent and focuses an image onto the two-dimensional surface of the array of fibers. These fibers, on the order of 10 micrometers, are bundled in groups of hundreds of thousands. Each pixel of a picture can be associated with a fiber in a one-to-one fashion of input light that is transferred from the objective end through the optical fiber relay, and magnified by the ocular to an output image on camera or seen with the naked eye. The elegant aspect is that these fibers may be twisted and flexed without damaging the image, which proves to be an integral element in many types of endoscopy. The optical layout discussed above has been simplified considerably; for spherical, chromatic, and other optical aberrations must be dealt with in order to manufacture a functional endoscope.

Not only must endoscopes be precisely organized optically, but great care must be taken to ensure their biocompatibility, since they come in close contact with extremely sensitive internal body surfaces. Accordingly, biocompatibility is of prime importance to the United States Food and Drug Administration (FDA), which considers endoscopes to be "short-term mucosal contacting, externally communicating devices and testing [for approval of use] should include, but is not limited to, mucosal irritation, sensitization, cytotoxicity, acute systemic toxicity, and short-term implantation."

Endoscopes may be used to observe and biopsy as well as to perform actual surgeries through tiny incisions in appropriate sites. The latter generally involves use of miniature video cameras and minute surgical instrumentation, often electrosurgical equipment, forceps, or biopsy attachments.

While fiberoptic technology utilizes extremely thin strands of glass or plastic to transmit light through repeated internal reflection along the optical fiber lengths for image formation and visualization, other forms of endoscopy have surfaced. Electronic endoscopes, which do not require fiber optics (yet possess a field-of-view identical to the fiber-optic endoscope as well as similar controls depressible by finger-tip, i.e. air insufflation, suction, and water injection) are also on the market. These devices boast a mounted computer chip (in reality three chips for red, blue, and green light) on the tip. They are lower-maintenance due to the lack of fiber optics, and images from them can easily be sent to a television monitor for the entire operating room to view. Even more recently (as of July 2001), technology has permitted the development of high-speed 3D endoscopic measurements.

Forms of endoscopy

The abundance of instruments falling under the designation "endoscope" includes the following, with brief descriptions of each:

• Amnioscope: Used to examine the fetus through the cervical canal prior to membrane breakage.
• Angioscope: Used to examine the interior of blood vessels . The scope must thus be very long, slender (generally on the order of 0.5 mm), and flexible to accomodate navigation of minute spaces and dynamic curvature.
• Arthroscope: Used to examine intraarticular surfaces of joints. Arthroscopes are rigid and contain stacks of optical lenses while the eyepiece is generally attached to a video camera. Due to the frequency of knee injuries, the arthroscope is most often used to diagnose and help treat knee damage.
• Bronchoscope: Aids in exploring the interior of the bronchi, their branches, and tracheal mucosa (the windpipe tissue lining).
• Choledochoscope: Used to examine the bile duct (duct carrying bile from the liver to the gallbladder or from the gallbladder to the small intestine ) during an open surgical procedure intraoperatively. Both rigid and flexible scopes are employed.
• Colonoscope: Used to examine the lower section of the bowel, the large intestine , i.e. the colon.
• Culdoscope: Used to examine the pelvis and its structures. The scope is normally introduced through a small incision in the posterior vaginal cul-de-sac.
• Cystoscope: Used to examine the urinary tract and bladder; it employs similar optics to the arthroscope, yet possesses a longer depth of insertion.
• Cystourethroscope: Used to examine the urethra, bladder, and distal ureter.

• Encephaloscope: Used to examine brain cavities.
• Endoscopic retrograde cholangiopancreatography: Used in diagnosis of pancreatic disease through injection of radio-opaque dye into biliary and pancreatic ducts while examining the duodenal area.
• Enteroscope: Used to examine the esophagus, small intestine, and stomach .
• Esophagogastroduodenoscope: Used to examine the esophagus, duodenum, and stomach.
• Esophagoscope: Used to examine the channel connecting the pharynx to the stomach.
• Gastroscope: Used to examine the stomach lumen.
• Gonioscope: Used to examine and help determine the configuration of the angle between the iris and cornea.
• Hysteroscope: Used to examine the passage of the uterine cervix and cavity.
• Laparoscope: Used to examine the peritoneal cavity through the anterior abodominal wall and is commonly rigid. This scope is the most common type used by the general surgeon.
• Laryngoscope: Used to examine the larynx (the sphincter at the entrance of the trachea).
• Mediastinoscope: Used to examine the mediastinum (mass of tissues and organs separating the lungs , i.e. the heart , esophagus, trachea, etc). Often used for visualization of lymph nodes and tumors in the superior mediastinum.
• Nephroscope: Used to examine the kidneys , i.e. the renal pelvis, calyces, and upper ureter. It is employed during open procedures intraoperatively.
• Proctoscope: Used to examine the rectum.
• Resectoscope: Used to perform resections of tissue as a part of a diagnostic or therapeutic procedure.
• Rhinoscope: Used to examine the nasal cavity.
• Sigmoidoscope: Used for direct examination of the sigmoid colon.
• Thoracoscope: Used to examine the pleural cavity through an intercostal space (space between adjacent ribs, filled by intercostals muscles).
• Ureteroscope: Used to examine the ureter.
• Urethroscope: Used to examine the urethra.

Operation

Endoscopic procedures are sometimes performed under local anesthesia , especially with regard to upper gastrointestinal endoscopy. However, the majority of patients are sedated entirely. After the appropriate anesthetic has been administered, the physician inserts the endoscope in the anatomically relevant position and views the patient. The anesthesiologist, meanwhile, remains busy watching for blood pressure drops and reductions in oxygen saturation; this concern has resulted in a mandate that elderly, cardiovascularly risky, and anemic patients receive extra oxygen during the procedure.

Of paramount importance is the disinfection of used endoscopes. Endoscopic cross-infection is rare, but does occur. According to Davidson's Principles and Practice of Medicine, cross-infection has occurred in three ways:

• Transmission of pathogenic organisms from one patient to another, with salmonella the most frequent organism.
• Transmission of infection , such as hepatitis B, to staff by needle-stick injury.
• Introduction of opportunistic organisms that colonize the instruments in storage. These may cause serious infection in immunocompromised patients and can cause sever biliary or pancreatic sepsis if introduced during endoscopic retrograde cholangiopancreatography. To eliminate this possibility, many medical practices have become accustomed to disinfecting endoscopes again in the morning before the first patient arrives.

To prevent the above from occurring, health personnel must abide by strict procedures. Endoscopes should be submerged in detergent and water immediately upon removal from a patient. Valves and other removable components (including such endoscopic accessories as biopsy forceps) must be meticulously cleansed with cotton tips and a soft toothbrush, while channels must be washed. Disinfection by immersion in 2% gluteraldehyde (or 10% succine dealdehyde) for at least 20 minutes is strongly recommended since the scrubbing does not wipe out bacteria entirely. Also, medical personnel should wear gloves and masks as well as eye protection for positive hepatitis B or HIV patients. The general guideline for endoscopic disinfection is fivefold: cleaning (by mechanical scrubbing); disinfecting (by immersion in guteraldehyde or some other high-level disinfectant); rinsing (using sterile water); drying (using forced air prior to storage); and storing (without recontaminating equipment, i.e. by hanging it vertically).

Maintenance

Proper care of endoscopes and endoscopic instrumentation should result in:

• enhanced life span of endoscopes and accessory instruments
• reduced repair and replacement costs
• low number of microorganisms, restricting infection possibilities

As indicated above, disinfection is a chief concern in the field of endoscopy. Proper disassembly, cleansing, rinsing, drying, storage, and reassembly of the equipment, all according to the manufacturer's instructions, can help it to remain viable and safe for a long while. Corrosion is a common cause of equipment failure; stainless steel can in fact spot and stain. According to the company Gamma Endoscopy, "when endoscopic instruments do spot or stain common causes are:

• very acid or alkaline pH detergents
• improperly dissolved detergent leaving residual powder
• high mineral content of the water used for cleaning, rinsing, or in the steam autoclave
• residual disinfection solution
• disinfection solutions with an acidic pH
• residual blood , organic matter, or irrigation solution (e.g. saline), especially if instruments are not completely disassembled or thoroughly cleaned
• chemical change resulting from prolonged exposure of dissimilar metals to electrolytic solutions (e.g. normal saline, disinfection solutions)
• scratches on instruments that allow corrosive agents to get below the passivation layer, a protective layer on the instrument surface

All moving parts should be lubricated before [reassembly] to prevent 'freezing' of stopcocks and forceps jaws. It is necessary to check the instruction manual to determine which parts to lubricate, and a waterbased lubricant may be used when reassembling portions of instruments before sterilization/disinfection. Because sterilization/disinfection mediums may not penetrate tight-locking mechanisms, endoscopic instruments should not be reassembled before sterilization or disinfection."

If all other methods fail, endoscopes may be sent to instrument refurbishment companies that specialize in endoscopic repair.

KEY TERMS

Fiber optics —A technology using glass (or plastic) fibers to transmit data. A fiber optic cable is simply a bundle of these threads, each of which is capable of transmitting light wave data. Fiber optic cables can carry much more data in less space than conventional metal wires (i.e. they have greater bandwidth), are thinner and lighter, and are appropriate for transmission of digital data. It is possible to construct flexible fiber bundles that are spatially aligned for use in endoscopic procedures.

Health care team roles

Physicians perform endoscopic procedures while nurses and other medical personnel aid them. Health personnel prepare the equipment prior to examination and play a critical role in disinfecting it after the procedure has culminated. Endoscopes and accessories should be examined by health care staff for structural integrity, proper function, and cleanliness before use; during the exam; immediately following disinfection procedures; and prior to disinfection/sterilization. It is also recommended that endoscopes and accessories be thoroughly tested before initial use and used in accordance with the manufacturer's manual.

Training

Training varies from procedure to procedure among the widely varying types of endoscopy; however, disinfection training is essentially similar, except that there are major differences in cleansing between rigid, flexible (the most difficult), and electronic endoscopes.

Resources

PERIODICALS

Dietze, B., H. Neuman, U. Mansmann, and H. Martiny. "Determination of Gluteraldehyde Residues on Flexible Endoscopes after Chemothermal Treatment in an Endoscope Washer-Disinfector." Endoscopy 33, no. 6 (2001): 529-532.

Hasegawa, K., and Y. Sato. "Endoscope system for high-speed 3D measurement." Systems and Computers in Japan 32, no. 8 (July 2001): 30-39.

ORGANIZATIONS

The Association of Perioperative Registered Nurses (AORN). AORN, Inc., 2170 South Parker Rd., Suite 300, Denver, CO 80231-5711. (800) 755-2676 or (303) 755-6300. <http://www.aorn.org>.

OTHER

Endoscope Tutorial. <http://www.leineroptics.com/endotut.htm>.

Bryan Ronain Smith

Endoscope

Definition

An endoscope is characterized by its often long, thin (sometimes flexible) lighted tube containing fiber-optical instrumentation attached to a viewing device through which one may closely observe, via the naked eye or an attached camera, the surface of a canal or hollow organ in the body.

Purpose

The endoscope is often used as a form of less invasive monitoring of the body instead of, or in conjunction with, surgery. A key aspect of the device is that it is not only capable of traversing the body to allow direct observation, but may also be equipped with endoscopic accessories that allow manipulation and diagnostic/therapeutic procedures to be performed much less invasively than more conventional surgical operations.

Endoscopic surgery minimizes pain, hospital stays, and recovery time, which is good for patients. Its use is also promoted by health insurance companies and hospital administrators inclined toward reduced costs as well as to offer the best treatment options technology can provide.

Description

The endoscope is a generalization of a broad variety of fiber-optical scopes used to elucidate diverse aspects of the body to medical practitioners for various purposes. Endoscopes come in two main categories: rigid and flexible. The rigid endoscope is designed with a rigid insertion tube and is preferred over flexible endoscopes when feasible because the rigidity allows use of optics that permit greater resolution and the absence of a visible lattice structure. However, it is more difficult to design and construct a rigid endoscope, which entails using lenses rather than fibers to transmit the image externally to the user or to a camera.

The fiber-optical endoscope can in general be viewed as a simple input/output device that utilizes an objective lens system along with a fiber relay and an ocular for magnification. The objective component is inserted directly into the body with a lighting constituent and focuses an image onto the two-dimensional surface of the array of fibers. These fibers, on the order of 10 micrometers, are bundled in groups of hundreds of thousands. Each pixel of a picture can be associated with a fiber in a one-to-one fashion of input light that is transferred from the objective end through the optical fiber relay, and magnified by the ocular to an output image on camera or seen with the naked eye. The elegant aspect is that these fibers may be twisted and flexed without damaging the image, which proves to be an integral element in many types of endoscopy. The optical layout discussed above has been simplified considerably; for spherical, chromatic, and other optical aberrations must be dealt with in order to manufacture a functional endoscope.

Not only must endoscopes be precisely organized optically, but great care must be taken to ensure their biocompatibility, since they come in close contact with extremely sensitive internal body surfaces. Accordingly, biocompatibility is of prime importance to the United States Food and Drug Administration (FDA), which considers endoscopes to be "short-term mucosal contacting, externally communicating devices and testing [for approval of use] should include, but is not limited to, mucosal irritation, sensitization, cytotoxicity, acute systemic toxicity, and short-term implantation."

Endoscopes may be used to observe and biopsy as well as to perform actual surgeries through tiny incisions in appropriate sites. The latter generally involves use of miniature video cameras and minute surgical instrumentation, often electrosurgical equipment, forceps, or biopsy attachments.

While fiberoptic technology utilizes extremely thin strands of glass or plastic to transmit light through repeated internal reflection along the optical fiber lengths for image formation and visualization, other forms of endoscopy have surfaced. Electronic endoscopes, which do not require fiber optics (yet possess a field-of-view identical to the fiber-optic endoscope as well as similar controls depressible by finger-tip, i.e. air insufflation, suction, and water injection) are also on the market. These devices boast a mounted computer chip (in reality three chips for red, blue, and green light) on the tip. They are lower maintenance due to the lack of fiber optics, and images from them can easily be sent to a television monitor for the entire operating room to view. Even more recently, technology has permitted the development of high-speed 3D endoscopic measurements.

Forms of endoscopy

The abundance of instruments falling under the designation "endoscope" includes the following, with brief descriptions of each:

• Amnioscope: Used to examine the fetus through the cervical canal prior to membrane breakage.
• Angioscope: Used to examine the interior of blood vessels. The scope must thus be very long, slender (generally on the order of 0.5 mm), and flexible to accomodate navigation of minute spaces and dynamic curvature.

• Arthroscope: Used to examine intraarticular surfaces of joints. Arthroscopes are rigid and contain stacks of optical lenses while the eyepiece is generally attached to a video camera. Due to the frequency of knee injuries, the arthroscope is most often used to diagnose and help treat knee damage.
• Bronchoscope: Aids in exploring the interior of the bronchi, their branches, and tracheal mucosa (the windpipe tissue lining).
• Choledochoscope: Used to examine the bile duct (duct carrying bile from the liver to the gallbladder or from the gallbladder to the small intestine ) during an open surgical procedure intraoperatively. Both rigid and flexible scopes are employed.
• Colonoscope: Used to examine the lower section of the bowel, the large intestine, i.e. the colon.
• Culdoscope: Used to examine the pelvis and its structures. The scope is normally introduced through a small incision in the posterior vaginal cul-de-sac.
• Cystoscope: Used to examine the urinary tract and bladder; it employs similar optics to the arthroscope, yet possesses a longer depth of insertion.
• Cystourethroscope: Used to examine the urethra, bladder, and distal ureter.
• Encephaloscope: Used to examine brain cavities.
• Endoscopic retrograde cholangiopancreatography: Used in diagnosis of pancreatic disease through injection of radio-opaque dye into biliary and pancreatic ducts while examining the duodenal area.
• Enteroscope: Used to examine the esophagus, small intestine, and stomach.
• Esophagogastroduodenoscope: Used to examine the esophagus, duodenum, and stomach.
• Esophagoscope: Used to examine the channel connecting the pharynx to the stomach.
• Gastroscope: Used to examine the stomach lumen.
• Gonioscope: Used to examine and help determine the configuration of the angle between the iris and cornea.
• Hysteroscope: Used to examine the passage of the uterine cervix and cavity.
• Laparoscope: Used to examine the peritoneal cavity through the anterior abodominal wall and is commonly rigid. This scope is the most common type used by the general surgeon.
• Laryngoscope: Used to examine the larynx (the sphincter at the entrance of the trachea).
• Mediastinoscope: Used to examine the mediastinum (mass of tissues and organs separating the lungs, i.e. the heart, esophagus, trachea, etc). Often used for visualization of lymph nodes and tumors in the superior mediastinum.
• Nephroscope: Used to examine the kidneys, i.e. the renal pelvis, calyces, and upper ureter. It is employed during open procedures intraoperatively.
• Proctoscope: Used to examine the rectum.
• Resectoscope: Used to perform resections of tissue as a part of a diagnostic or therapeutic procedure.
• Rhinoscope: Used to examine the nasal cavity.
• Sigmoidoscope: Used for direct examination of the sigmoid colon.
• Thoracoscope: Used to examine the pleural cavity through an intercostal space (space between adjacent ribs, filled by intercostals muscles).
• Ureteroscope: Used to examine the ureter.
• Urethroscope: Used to examine the urethra.

Operation

Endoscopic procedures are sometimes performed under local anesthesia, especially with regard to upper gastrointestinal endoscopy. However, the majority of patients are sedated entirely. After the appropriate anesthetic has been administered, the physician inserts the endoscope in the anatomically relevant position and views the patient. The anesthesiologist, meanwhile, remains busy watching for blood pressure drops and reductions in oxygen saturation; this concern has resulted in a mandate that elderly, cardiovascularly risky, and anemic patients receive extra oxygen during the procedure.

Of paramount importance is the disinfection of used endoscopes. Endoscopic cross-infection is rare, but does occur. According to Davidson's Principles and Practice of Medicine, cross-infection has occurred in three ways:

• Transmission of pathogenic organisms from one patient to another, with salmonella the most frequent organism.
• Transmission of infection, such as hepatitis B, to staff by needle-stick injury.
• Introduction of opportunistic organisms that colonize the instruments in storage. These may cause serious infection in immunocompromised patients and can cause severe biliary or pancreatic sepsis if introduced during endoscopic retrograde cholangiopancreatography. To eliminate this possibility, many medical practices have become accustomed to disinfecting endoscopes again in the morning before the first patient arrives.

To prevent the above from occurring, health personnel must abide by strict procedures. Endoscopes should be submerged in detergent and water immediately upon removal from a patient. Valves and other removable components (including endoscopic accessories such as biopsy forceps) must be meticulously cleansed with cotton tips and a soft toothbrush, while channels must be washed. Disinfection by immersion in 2% gluteraldehyde (or 10% succine dealdehyde) for at least 20 minutes is strongly recommended since the scrubbing does not wipe out bacteria entirely. Also, medical personnel should wear gloves and masks as well as eye protection for positive hepatitis B or HIV patients. The general guideline for endoscopic disinfection is fivefold: cleaning (by mechanical scrubbing); disinfecting (by immersion in guteraldehyde or some other high-level disinfectant); rinsing (using sterile water); drying (using forced air prior to storage); and storing (without recontaminating equipment, i.e. by hanging it vertically).

Maintenance

Proper care of endoscopes and endoscopic instrumentation should result in:

• enhanced life span of endoscopes and accessory instruments
• reduced repair and replacement costs
• low number of microorganisms, restricting infection possibilities

As indicated above, disinfection is a chief concern in the field of endoscopy. Proper disassembly, cleansing, rinsing, drying, storage, and reassembly of the equipment, all according to the manufacturer's instructions, can help it to remain viable and safe for a long while. Corrosion is a common cause of equipment failure; stainless steel can in fact spot and stain. According to the company Gamma Endoscopy, "when endoscopic instruments do spot or stain common causes are:

• very acid or alkaline pH detergents
• improperly dissolved detergent leaving residual powder
• high mineral content of the water used for cleaning, rinsing, or in the steam autoclave
• residual disinfection solution
• disinfection solutions with an acidic pH
• residual blood, organic matter, or irrigation solution (e.g. saline), especially if instruments are not completely disassembled or thoroughly cleaned
• chemical change resulting from prolonged exposure of dissimilar metals to electrolytic solutions (e.g. normal saline, disinfection solutions)
• scratches on instruments that allow corrosive agents to get below the passivation layer, a protective layer on the instrument surface

All moving parts should be lubricated before [reassembly] to prevent 'freezing' of stopcocks and forceps jaws. It is necessary to check the instruction manual to determine which parts to lubricate, and a water-based lubricant may be used when reassembling portions of instruments before sterilization/disinfection. Because sterilization/disinfection mediums may not penetrate tight-locking mechanisms, endoscopic instruments should not be reassembled before sterilization or disinfection."

If all other methods fail, endoscopes may be sent to instrument refurbishment companies that specialize in endoscopic repair.

KEY TERMS

Fiber optics— A technology using glass (or plastic) fibers to transmit data. A fiber optic cable is simply a bundle of these threads, each of which is capable of transmitting light wave data. Fiber optic cables can carry much more data in less space than conventional metal wires (i.e. they have greater bandwidth), are thinner and lighter, and are appropriate for transmission of digital data. It is possible to construct flexible fiber bundles that are spatially aligned for use in endoscopic procedures.

Health care team roles

Physicians perform endoscopic procedures while nurses and other medical personnel aid them. Health care personnel prepare the equipment prior to examination and play a critical role in disinfecting it after the procedure has culminated. Endoscopes and accessories should be examined by health care staff for structural integrity, proper function, and cleanliness before use; during the exam; immediately following disinfection procedures; and prior to disinfection/sterilization. It is also recommended that endoscopes and accessories be thoroughly tested before initial use and used in accordance with the manufacturer's manual.

Training

Training varies from procedure to procedure among the widely varying types of endoscopy; however, disinfection training is essentially similar, except that there are major differences in cleansing between rigid, flexible (the most difficult), and electronic endoscopes.

Resources

PERIODICALS

Dietze, B., H. Neuman, U. Mansmann, and H. Martiny. "Determination of Gluteraldehyde Residues on Flexible Endoscopes after Chemothermal Treatment in an Endoscope Washer-Disinfector." Endoscopy 33, no. 6 (2001): 529-532.

Hasegawa, K., and Y. Sato. "Endoscope system for high-speed 3D measurement." Systems and Computers in Japan 32, no. 8 (July 2001): 30-39.

ORGANIZATIONS

The Association of Perioperative Registered Nurses (AORN). AORN, Inc., 2170 South Parker Rd., Suite 300, Denver, CO 80231-5711. (800) 755-2676 or (303) 755-6300. 〈http://www.aorn.org〉.

OTHER

Endoscope Tutorial. 〈http://www.leineroptics.com/endotut.htm〉.

Endoscopy

KEY TERMS

Resources

Endoscopy is the use of a thin, lengthy, flexible scope that can be inserted into the body for the diagnosis and treatment of various conditions. Until the last third of the twentieth century, one of the limiting factors in the treatment of internal injuries or diseases was the need to perform open surgery. That meant general anesthesia, carrying out the operation, sewing up the incision, and allowing the patient to recuperate from the procedure for several days in the hospital. In some instances, such as trauma, the need for open surgery only added to the time involved for the patient to be treated.

For many years surgeons had attempted various means to penetrate the interior of the body without the need for a major incision.

The use of x rays allowed observation of bones and, with some enhancement, certain organs and blood vessels. Although this procedure gave ample information about bone fractures and at times even bone cancer, x rays gave evidence of a tumor or other disease process without telling the physician what caused the condition. Knowing the tumor or disease was present did not remove the need for surgical treatment.

Clearly, a method was needed to look into the body to observe a pathologic condition as it existed rather than as a shadow on an x-ray plate.

As early as 1918, a physician named Takagi was attempting to use the technology of the day to examine the interior of joints. He used a cystoscope, an instrument used to examine the interior of the urinary bladder, but immediately came upon major problems. The cystoscope was a rigid tube with a light on it that was inserted in the urethra to examine the urinary bladder. Because it was rigid, the instrument was not maneuverable or flexible enough to be guided around various anatomic structures. The light on the cystoscope was at the far end and could easily be broken off inside the patient. Also the heat of the lamp, small as it was, soon heated the joint space to an unacceptable level, far too quickly for the doctor to carry out a thorough examination.

Technology available by the late 1970s, however, solved these problems and allowed a specialty to begin that today is widespread and beneficial. The space age brought on the science of fiber optics, long strands of glass that could carry light and electricity over long distances, around corners, in a small bundle compared to copper wires. Using fiber optics, the light source for the endoscope could be housed in the handle end of the scope so that the light itself never entered the body. Fiber optics also allowed the instrument to be flexible so that the doctor could steer the end into whatever area was wanted. The efficiency of fiber optics in carrying light and images meant that the diameter of the endoscope could be reduced considerably compared with the few scopes then available.

At first, the endoscope was called the arthroscope and used only to visualize the internal anatomy of joints such as the knee. Soon the scope was fitted with instruments such as scalpels and scissors to carry out surgery, a vacuum line to suck out any floating material that might interfere with the function of the joint, and a television camera so the physician, instead of peering through a small opening in the scope, could watch his progress on a larger television screen.

With these and other refinements the endoscope now can be used to penetrate nearly any area of the body, provide the physician with information on the condition of the area being examined, and the means to carry out surgical procedures through a tiny incision. The patient usually is in and out of the treatment facility the same day and the recovery from such minor surgery is rapid.

Like any other surgery, endoscopy is carried out in a sterile environment. The patient is positioned and appropriate anesthetic is administered. Often the area to be examined is filled with saline to expand the interior space and lift the overlying tissues from the area being examined. Saline is a mild salt solution. Through a small incision the tip of the endoscope is inserted into the joint space. The end of the endoscope being held by the surgeon has a “joy stick,” a lever that protrudes and that can be used to guide the tip of the endoscope from one area into another. A second endoscope may be needed to assist with surgery, provide more light, maintain the saline environment, or for any of a number of other reasons. Using the lever the physician moves the tip of the endoscope with the TV camera from one area to another, examining the structures within the joint.

The use of the endoscope to penetrate joints is called arthroscopy. It is an especially useful procedure in sports medicine where athletes often suffer knee injuries as the result of running, jumping, or being tackled. The ligaments that hold the lower leg bone, the tibia, to the upper leg bone, the femur, can be ruptured if the knee is twisted or hit from the side. Arthroscopy allows the surgeon to examine the details of the injury, determine whether a more radical procedure is needed, and if not, to repair the torn ligaments and remove any loose material from the joint using the arthroscope. The athlete will require a few weeks of physical therapy to regain full strength, but the actual surgery can be completed in only a short time and he will be out of the hospital the same day he enters.

The laparoscope or peritoneoscope (so named because it penetrates the peritoneum, the lining of the abdominal cavity) is used to examine the interior of the abdomen. The scope tip with TV camera attached can be guided around, above, and underneath the organs of the abdomen to determine the source of bleeding, the site of a tumor, or the probable cause of an illness. In the case of gallstones, which form in the gallbladder near the liver, the gallbladder can be removed using the surgical attachments. Suturing the stump of the gallbladder can also be accomplished using the attachments.

The scope used to examine the inner surface of the lower digestive tract is the sigmoidoscope. It can be

KEY TERMS

Arthroscope— Literally, “to examine the joint.” An instrument to examine the inside of a joint such as the knee. Sometimes called the arthroendoscope.

Pathology— An abnormality or disease; differing from healthy.

Peritoneum— A thin, fibrous sheet that lines the abdomen.

passed into the colon to examine the walls of the intestine for possible cancer or other abnormal structures.

Obviously, the physician using the endoscope must be highly knowledgeable about anatomy. Human anatomy as it appears through the lens of the scope is considerably different from its appearance on the page of a book or during open surgery. The physician must be able to recognize structures, which may appear distorted through the lens of the endoscope, to determine the location of the tip of the endoscope and to know where to maneuver the scope next. Training is carried out under the guidance of a physician who has extensive experience with the endoscope.

Resources

PERIODICALS

Bechtel, S. “Operating through a Keyhole.” Prevention 45 (July, 1993): 72+.

Frandzel, S. “The Incredible Shrinking Surgery.” American Health 13 (April, 1994): 80-84.

OTHER

Imaginis. “Medical Procedures: Endoscopy” <http://www.imaginis.com/endoscopy/> (accessed November 24, 2006).

World Gastroenterology Organisation. “The History and Impact of Flexible Endoscopy” <http://www.omge.org/publications/archive/2001_3/lect/lect1.htm> (accessed November 24, 2006).

Larry Blaser

Endoscopy

Definition

An endoscopy is a procedure that uses a small camera mounted on a thin, flexible tube called an endoscope to allow a doctor to see inside the body.

Purpose

Endoscopy is used to provide the doctor or surgeon with the ability to see inside the patient's body. Unlike many other forms of imaging, such as x-ray and ultrasound, endoscopy can provide the doctor with a real-time view with true colors. It also is sometimes used to remove polyps, cauterize bleeding, or remove samples for examination under the microscope.

Endoscopy is used in a variety of settings. It is often used to help diagnose the cause of pain or other symptoms that are of unclear origin. It can also be used during minimally invasive surgery, when an endoscopy is passed through a very small incision so that the surgeon is able to view the inside of the patient and perform the surgery.

Precautions

The precautions for endoscopy vary depending on the type of endoscopy performed. Individuals who have conditions that require regular consumption of food or liquids may not be good candidates for endoscopy. Individuals who are allergic to one or more sedatives or anesthesia products should alert their doctor and health care team so that alternative medications can be found and special precautions can be taken.

Description

During endoscopy, a small camera or viewer attached to the end of a thin, usually flexible tube, is passed into the individual. This device is called an endoscope. The endoscope is usually introduced into the patient through the mouth, rectum, ureter, or a small incision. The place of endoscope entry is determined by the are of the body the doctor wishes to view.

Some endoscopes have a view piece that allows the doctor to see directly into the patient. Others have camera at the end, which sends video signals through fiber optic wires in the endoscope to a television monitor in the procedure room. This allows the doctor and others to get a clear, enlarged view of the area of interest, and can allow for recording the procedure to review later if there are any questions.

In most cases the patient is mildly or heavily sedated during the procedure. Many patients actual sleep through the majority of the procedure. The area under investigation may also receive local anesthesia if discomfort from the procedure is expected.

Many endoscopes allow the doctor not only to see the inside of the patient, but also to perform some additional procedures. Some endoscopes have a device for cauterizing as an available attachment, which can be sued to stop internal bleeding in the area being investigated. Other endoscopes allow the doctor to cut and remove polyps during the procedure. Some endoscopes allows for the biopsy of suspicious tissue during the procedure, removing the need for an additional, usually more invasive procedure later.

Preparation

The preparation for an endoscopy depends heavily on the type of endoscopy being performed. The patient is generally instructed not to eat or drink for a certain amount of time before the procedure. If there is food in the upper digestive system this can reduce visibility, and vomiting can occur causing complications. If an endoscopy is being performed on the lower digestive tract the patient may be prescribed laxatives or one or more enemas before the procedure so that the area of interest is clearly visible.

The patient may be required to stop taking, or reduce the dosage of, some medications, supplements, or herbs before the procedure. Blood thinners can increase the risk of bleeding as a complication of the procedure, so individuals taking blood thinners may be asked to stop for a few days before the procedure. The patient is given specific instructions for his or her case, usually when the endoscopy is scheduled.

Aftercare

After the endoscopy the patient is often brought to a special recovery room to wait until the effects of any sedatives administered wear off, and to ensure there were no complications from the procedure. The patient should arrange for transportation home after the procedure because he or she will not be able to drive after sedation. Generally, patients can begin to eat and drink again as desired after the procedure is over. The patient will generally begin to feel better quickly as any medication administered wears off, although some soreness may occur. The patient should usually allow the remainder of the day to rest after the procedure.

Complications

An endoscopy can result in soreness in the area in which the endoscopy was performed. Bloating and gas sometimes occur after endoscopies performed on the gastrointestinal tract. In rare cases endoscopy can cause bleeding, and in extremely rare cases can cause rupture or tearing of the intestinal wall. If anesthesia or sedatives were used these can have their own risks of complications. In most cases no serious complications result from endoscopy.

Results

An endoscopy produces pictures of the area being looked at so that the doctor can use them to assist in making a diagnosis. In some cases the endoscopy will also produce samples that can be examined under the microscope. The results of the endoscopy will vary depending on the reason it was performed, the area examined, and whether any biopsies were taken. A normal endoscopy will produce images that show healthy, normally functioning organs with no tears, growths, or bleeding. An abnormal endoscopy may show growths, bleeding, tearing of the intestinal wall, abnormal coloration, or a variety of other problems.

Caregiver concerns

A doctor determines the need for an endoscopy based on a physical examination of the patient, the

QUESTIONS TO ASK YOUR DOCTOR

• Should I continue to take my medications, vitamins, and supplements as usual before the procedure?
• When should I stop eating and drinking before the procedure?
• When can I expect to return to my normal activities after the procedure?

patient's self-reported symptoms, a health history , and the results of any other diagnostic imaging, blood, or urine tests. The endoscopy may be performed in a doctor's office, in a clinic, or in a hospital. In general, an endoscopy is performed by a doctor who specializes in the area being imaged. For example, an endoscopy of the upper digestive system is performed by a gastroenterologist, a doctor who specializes in the gastrointestinal system. A surgeon may perform an endoscopy if the endoscopy is being used to visualize the surgery site during minimally invasive surgery.

During the procedure a variety of other health care team members may assist the doctor or surgeon who is performing the endoscopy. Technologists may help to set up and monitor video and other equipment. One or more nurses may supervise the administration of any medications or relaxants, and may help to monitor the patient's vital signs during the procedure. If the patient is going to be under general anesthesia during the procedure an anesthesiologist will administer the anesthesia and be present during the procedure to monitor the patient. If the endoscopy is being performed doing a surgery a variety of operating room nurses, technologists, and technicians may be present to assist. If any material is removed during the procedure a laboratory technician may examine the sample to determine if it is cancerous.

Resources

BOOKS

Faigel, Douglas O. and Michael L. Kochman, eds. Endoscopic Oncology: Gastrointestinal Endoscopy and Cancer Management. Totowa, NJ: Humana Press, 2006.

Nahai, Foadand Renato Saltz, eds. Endoscopic Plastic Surgery, 2nd ed. St. Louis, MO: Quality Medical Pub. 2007.

Ogilvie, Jeanette, Lisa M. Hicks, and Anthony N. Kallo. John Hopkins Manual for Gastrointestinal Endoscopy Nursing, 2nd ed. Thorofare, NJ: Slack, 2008.

PERIODICALS

Misra, Sri Prakash, and Manisha Dwivedi. “Colonoscopy and Colonscopic Polypectomy Using Side-Viewing Endoscope: A Useful, Effective, and Safe Procedure.” Digestive Disease and Sciences 53.5 (May 2008): 1285–1289.

Pedersen, Amanda. “Study: Endoscopy Found Safe for Gastric Bypass Complication.” Medical Device Week (August 20, 2007).

ORGANIZATIONS

American Gastroenterological Association, 4930 Del Ray Avenue, Bethesda, MD, 20814, (310) 654-2055, (310) 654-5920, www.gastro.org.

Robert Bockstiegel

Endoscopy

Endoscopy is the use of a thin, lengthy, flexible scope that can be inserted into the body for the diagnosis and treatment of various conditions. Until the last third of the twentieth century, one of the limiting factors in the treatment of internal injuries or diseases was the need to perform open surgery on the patient. That meant putting him under anesthesia , carrying out the operation, sewing up the incision, and allowing the patient to recuperate from the procedure for several days in the hospital. In some instances, such as trauma, the need for open surgery only added to the time involved for the patient to be treated.

Surgeons for many years had attempted various means to penetrate the interior of the body without the need for a major incision.

The use of x rays allowed observation of bones and, with some use of enhancement, certain organs and the blood vessels. Although this procedure gave ample information about bone fractures and at times even bone cancer , x rays gave evidence of a tumor or other disease process without telling the physician what actually was the cause of the condition. Knowing the tumor or disease was present did not remove the necessity of surgical diagnosis. Clearly, a method was needed to look into the body to observe a pathologic condition as it existed rather than as a shadow on an x-ray plate.

As early as 1918, a physician named Takagi was attempting to use the technology of the day to examine the interior of joints. He used a cystoscope, an instrument used to examine the interior of the urinary bladder, but immediately came upon major problems. The cystoscope was a rigid tube with a light on it that was inserted in the urethra to examine the urinary bladder. Because it was rigid the instrument was not maneuverable or flexible enough to be guided around various anatomic structures. The light on the cystoscope was at the far end and could be broken off easily inside the patient. Also the heat of the lamp, small as it was, soon heated the joint space to an unacceptable level, far too quickly for the doctor to carry out a thorough examination.

Technology available by the late 1970s, however, solved these problems and allowed a specialty to begin that today is widespread and beneficial. The space age brought on the science of fiber optics , long strands of glass that could carry light and electricity over long distances, around corners, in a small bundle compared to copper wires. Using fiber optics, the light source for the endoscope could be housed in the handle end of the scope so that the light itself never entered the body. Fiber optics also allowed the instrument to be flexible so that the doctor could steer the end into whatever area he wanted. The efficiency of fiber optics in carrying light and images meant that the diameter of the endoscope could be reduced considerably compared with the few scopes then available.

At first, the endoscope was called the arthroscope and used only to visualize the internal anatomy of joints such as the knee. Soon the scope was fitted with instruments such as scalpels and scissors to carry out surgery, a vacuum line to suck out any floating material that might interfere with the function of the joint, and a television camera so the physician, instead of peering through a small opening in the scope, could watch his progress on a larger television screen.

With these and other refinements the endoscope now can be used to penetrate nearly any area of the body, provide the physician with information on the condition of the area being examined, and provide the means for the physician to carry out surgical procedures through a tiny incision. The patient usually is in and out of the treatment facility the same day and the recovery from such minor surgery is rapid.

Like any other surgery, endoscopy is carried out in a sterile environment. The patient is positioned and appropriate anesthetic is administered. Often the area to be examined is filled with saline to expand the interior space and lift the overlying tissues from the area being examined. Saline is a mild salt solution. Through a small incision the tip of the endoscope is inserted into the joint space. The end of the endoscope being held by the surgeon has a "joy stick," a lever that protrudes and that can be used to guide the tip of the endoscope from one area into another. A second endoscope may be needed to assist with surgery, provide more light, maintain the saline environment, or for any of a number of other reasons. Using the lever the physician moves the tip of the endoscope with the TV camera from one area to another, examining the structures within the joint as he goes.

The use of the endoscope to penetrate joints is called arthroscopy. It is an especially useful procedure in sports medicine where athletes often suffer knee injuries as the result of running, jumping, or being tackled. The ligaments that hold the lower leg bone, the tibia, to the upper leg bone, the femur, can be ruptured if the knee is twisted or hit from the side. Arthroscopy allows the surgeon to examine the details of the injury, determine whether a more radical procedure is needed, and if not, to repair the torn ligaments and remove any loose material from the joint using the arthroscope. The athlete will require a few weeks of physical therapy to regain full strength, but the actual surgery can be completed in only a short time and he will be out of the hospital the same day he enters.

The laparoscope or peritoneoscope (so named because it penetrates the peritoneum, the lining of the abdominal cavity) is used to examine the interior of the abdomen. The tip of the scope with the TV camera attached can be guided around, above, and underneath the organs of the abdomen to determine the source of bleeding, the site of a tumor, or the probable cause of an illness. In the case of gallstones, which form in the gallbladder near the liver, the gallbladder can be removed using the surgical attachments. Suturing the stump of the gallbladder can also be accomplished using the attachments.

To examine the inner surface of the lower digestive tract the scope used is the sigmoidoscope. It can be passed into the colon to examine the walls of the intestine for possible cancer or other abnormal structures.

Obviously, the physician using the endoscope must be highly knowledgeable about anatomy. Human anatomy as it appears through the lens of the scope is considerably different from its appearance on the page of a book or during open surgery. The physician must be able to recognize structures, which may appear distorted through the lens of the endoscope, to determine the location of the tip of the endoscope and to know where to maneuver the scope next. Training is carried out under the guidance of a physician who has extensive experience with the endoscope.

Resources

periodicals

Bechtel, S. "Operating Through a Keyhole." Prevention 45 (July 1993): 72+.

Frandzel, S. "The Incredible Shrinking Surgery." AmericanHealth 13 (April 1994): 80-84.

Larry Blaser

KEY TERMS

Arthroscope

—Literally, "to examine the joint." An instrument to examine the inside of a joint such as the knee. Sometimes called the arthroendoscope.

Pathology

—An abnormality or disease; differing from healthy.

Peritoneum

—A thin, fibrous sheet that lines the abdomen.