Joel F. Panish

Superiority of the Flexible to the Rigid Sigmoidoscope in Routine Proctosigmoidoscopy

THE annual incidence of colorectal cancer in the United States is 100,000 cases, and the five-year survival rate for all stages, 41 per cent, has remained unchanged for the past 25 years.1 , 2 Heav...

Limitations and complications of colonoscopy

The major limiting factor in colonoscopy is the endoscopist. It depends on his training, experience, inherent ability, and honesty. I do not believe that the number of examinations performed by an aspiring endoscopist during training are really as important as some persons have stated. There are some trainees who will be able to perform colonoscopy after 10 procedures and some who will never learn it, no matter how many they perform. Experience is a great help to those people who have a natural knack for learning this technique. It does demand a hand-eye coordination that some people master very well, most people master fairly well, and some not at all. Honesty plays a role in this endeavor as it does in the practice of any type of medicine. However, I am beginning to see occurrences in gastrointestinal endoscopy that I do not like. It is too easy for the endoscopist to state that he has done a full colonoscopy when in reality he has reached only the splenic flexure, or to say that he has performed a left-sided colonoscopy with a flexible sigmoidoscope when he may have reached only the midsigmoid region. Although there is no practical way to monitor these misapprehensions, I do think it is important to continue to mention them. Perhaps they will decrease. The next limitation is the gastrointestinal assistant. Colonoscopy is extremely difficult without experienced help. Biopsy and polypectomy are much easier if you have someone helping you who knows what he is doing. The third limitation of colonoscopy is the organ itself. I have not gone into preparation of the colon because I think that was washed through thoroughly earlier in this symposium. The colon itself may present some anatomic problems. In addition to Dr. Haubrichs mention that an imperforate anus offers an impediment to colonoscopy, we do occasionally encounter patients with an anal stricture where the opening is less than 1 cm. Therefore, colonoscopes which have an outside diameter of approximately 1.3 cm cannot be introduced without difficulty. If the examination is essential, using general anesthesia, these patients can usually have the anus dilated and then successfully undergo colonoscopy. An extremely convoluted sigmoid colon is more difficult to intubate than a straight sigmoid colon. The greatest limitation that I have encountered is the presence of pelvic adhesions due to previous surgery or old diverticulitis, making it relatively unsafe to pursue a total colonoscopic examination. This occurs approximately 5% of the time with experienced examiners and perhaps as often as 30 to 40% of the time with inexpert colonoscopists. As a general rule, if you are having difficulty and the patient is experiencing discomfort, do nol proceed. The presence of diverticulosis is less of a limiting factor the more experience one gains. The examination is contraindicated in the presence of active diverticulitis. Sometimes the use of glucagon in the presence of marked sigmoid hypermuscularity and diverticulosis may be of help in facilitating examination. Other areas that may be difficult to examine are the splenic flexure, the deep pelvic transverse colon, a redundant hepatic flexure, and the ileocecal valve. Certain areas are more inaccessible than others, for example, the rectosigmoid junction, the sigmoid-descending colon junction, obstructing carcinomas, mesial inftiior aspects of the proximal splenic and hepatic flexures, and a mobile cecum. Certain techniques may help in these regions. The singlechannel endoscope gives a much better view of these areas because it can be turned back on itself owing to a greater degree of flexion. The double-channel endoscope, which may be preferable for polypectomy, does not lend itself as well to a sharp turning radius and is more likely to miss the lesions in these areas. If one is faced with a known lesion on barium enema in one of these difficult areas and the double-channel endoscope is in use and the lesion is not visible, switching to the more flexible, single-channel endoscope may be helpful in facilitating observation of the lesion. If the lesion still is not visible, then the barium enema should be repeated in order to see whether the radiologic or the colonoscopic examination is correct. The final limiting factor in colonoscopy is the instrument itself. I have already mentioned the inherent incapabilities of the 2 different types of instruments. Breakage of the instrument decreases as the colonoscopists experience increases. There is more breakage in a teaching institution because residents, fellows, and other trainees are learning the procedure. The more the instrument is used by a variety of people, the higher the rate of breakage. Instruments, by and large, appear to be more sturdily made now than they have been in the past. Another problem is that the biopsy specimens we obtain are sometimes difficult to interpret because of their small size and the artifacts that result from crushing. Larger and safer biopsy forceps are being developed, and these should lessen the limitations of biopsy. Lastly, of course, the performance of colonoscopy is contingent on the patients informed consent and cooperation. Major complications of colonoscopy are hemorrhage, perforation, bacteremia, mesenteric and serosal laceration,

Endoscopic findings in melanoma metastatic to the stomach

An instructive case of melanoma metastatic to the stomach is documented by gastroscopic photography and biopsy. Umbilicated lesions typical of metastatic melanoma are illustrated.

The potential of a zoom lens system in fiber endoscopy

A zoom lens system has been adapted to fiberendoscopy. The authors have found this system to enhance the view of distant lesions in otherwise obscure situations, to facilitate biopsy, and to improve photography. Corollary editorial comment follows in this issue.

An improved multi-purpose teaching attachment

A new rigid teaching attachment has been developed that fits all endoscopes, flexible as well as rigid. Its optical performance is reported to be superior to that of flexible fiberoptic attachments in general use.