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An alternative to transcolonic polypectomy, transabdominally directed, transanal colonoscopic polypectomy, for patients who require polyp removal but in whose cases standard colonoscopic approach has failed is presented. The early results are excellent, and the method also can be applied to other patients who have colonic polyps who undergo procedures such as hysterectomy and cholecystectomy.
The safety, efficacy and utility of various therapeutic gastrointestinal (GI) endoscopic procedures performed on children (January 1992 to July 1995) at a tertiary referral centre in India were studied. A total of 1,030 sessions (upper GI 972 and lower GI 58) of therapeutic GI endoscopy were performed in 162 children (mean age 7.4 +/- 4 years; upper GI 115, lower GI 47). Various upper GI endoscopic procedures done were injection sclerotherapy (EIS), endoscopic variceal ligation (EVL), bougie dilatation of oesophageal strictures, balloon dilatations of oesophageal stricture/pyloric obstruction and retrieval of foreign bodies in 75%, 6%, 9%, 4% and 12% of children respectively. Therapy for bleeding from oesophageal varices constituted the major group (75%). Repeated EIS (sessions total--876, mean 8, range 5-15) performed on 86 children resulted in control of bleeding in all and eradication of oesophageal varices in 85% of cases. Minor complications (oesophageal ulcers and oesophageal strictures) due to EIS were observed in 9% of children. EVL (10 sessions in 7 children) was effective in controlling bleeding and substantial decrease of varices in all without any complication. Oesophageal dilation either by bougie (61 sessions in 10 children) or balloon (6 sessions in 3 children) were performed for benign strictures. Balloon dilatation of pyloric obstruction was successfully done in 2 children. Foreign bodies (retained or sharp) were retrieved from upper GI tract in 14 children. No complications were observed with stricture dilatation/foreign body retrieval. Therapeutic lower GI endoscopies were performed in 47 children (colonoscopic polypectomy in 92%, anal dilatation and piles banding in 4% each). One child with juvenile polyposis coli developed sigmoid colon performation following colonoscopic polypectomy which required surgical correction. We conclude that upper and lower GI endoscopic therapeutic procedures in children are highly effective and safe. The risk of major complication is very small in experienced hands and occasional minor complications, can be managed conservatively.
Although a sliding tube made of plastics is very effective to keep the sigmoid colon in a straight position, there is some difficulty in handling the colonoscope, being restricted by the length of the scope. For the purpose of covering the demerits of the conventional sliding tube, a new slit sliding tube which is made up of three parts was devised by us. After straightening the sigmoidal loop, the three parts of the apparatus are joined together. Then the slit sliding tube is inserted into the descending colon with safety and ease. By using the slit sliding tube, handling of the colonoscope is scarcely restricted and becomes easy. Moreover, the slit sliding tube can be used even for the shorter scopes, by which the distal parts of the colon can be more easily examined in comparison with conventional techniques.
Feasibility and diagnostic performance of digital radiography in gastrointestinal imaging have not been fully investigated. We performed double-contrast barium enema study with computed radiography (CR-DCBE) on a routine basis, and the efficacy of this system for detection of colorectal polyps was investigated. The files of 76 patients, who had undergone both CR-DCBE and colonoscopy, were reviewed by two observers who were blinded to the colonoscopic findings. The radiation dose of CR-DCBE was reduced to 50% of conventional film-screen system. By using colonoscopic findings as a reference, the sensitivity and positive predictive value for colorectal polyps were 66% to 71% and 32% to 41%, respectively. There was no significant interobserver difference. The use of postprocessing with gray-scale reversal and edge enhancement did not significantly improve the results. The sensitivity for polyps smaller than 1 cm was comparable with published data of conventional film-screen systems. Our preliminary results show that CR-DCBE has an acceptable sensitivity for detection of colorectal polyps. It is suggested that the use of CR is a promising approach to digital gastrointestinal radiography.
BACKGROUND: To assess the appropriateness of utilization patterns for the barium enema and colonoscopy in a Medicaid population. METHODS: From 1987 to 1991, a Medicaid managed-care database in Philadelphia revealed claims for a total of 2357 outpatient barium enemas and 896 outpatient colonoscopic examinations. The database was reviewed to determine the primary diagnostic (ICD-9-CM) codes assigned to patients who underwent these procedures. These codes were used as a proxy for indications. Each of the diagnostic codes for barium enema and colonoscopy was then classified either as appropriate, inappropriate, equivocal, or miscoded based on current guidelines in the medical literature. RESULTS: A total of 1962 claims (83%) for barium enema were classified as appropriate, 126 (5%) as inappropriate, 84 (4%) as equivocal, and 185 (8%) as miscoded, whereas 645 claims (72%) for colonoscopy were classified as appropriate, 176 (20%) as inappropriate, 65 (7%) as equivocal, and 10 (1%) as miscoded. Thus, significantly more colonoscopic examinations were rated as inappropriate (p < 0.001). CONCLUSION: Our study suggests that more stringent criteria need to be used by physicians in ordering diagnostic examinations of the colon, particularly colonoscopy. Further investigation of the appropriateness of these procedures and the development and dissemination of guidelines seems warranted.
BACKGROUND: To evaluate the potential of magnetic resonance colonography (MRC) in detecting colorectal mass lesions. METHODS: Twenty patients underwent MR imaging (MRI) before colonoscopy. The colon was filled with a gadolinium (0.5 mol):water mixture (1:100) under MRI control, and patients were imaged while breath-holding imaged with a three-dimensional spoiled gradient echo sequence in the prone and supine positions. Images were interactively analyzed based on the combination of multiplanar reconstruction and virtual colonoscopy by a radiologist blinded to colonoscopic findings and the patient's history. MRC interpretations were correlated with colonoscopic results. RESULTS: Polyps smaller than 5 mm could not be identified with MRC. The sensitivity for detecting polyps of 5-10 mm was 70%, whereas mass lesions larger than 10 mm were all detected (sensitivity = 100). The sensitivity, specificity, and accuracy for identifying polyp-positive patients including the three patients with small (<5 mm) polyps were 64%, 89%, and 75%, respectively. CONCLUSION: Virtual colonoscopy based on MRI data is feasible and should be evaluated in a larger sample of patients.
Patients with ulcerative colitis (UC) are at increased risk for colorectal carcinoma (CAC). Despite the fact that patients at risk are followed closely by colonoscopy to screen for dysplasia, the prevalence of CAC is still unacceptably high. The aim of this study was to evaluate the prevalence of risk factors for CAC, such as dysplasia, and to determine the relevance of colonoscopic surveillance in the group who went on to develop cancer. A series of 24 patients with UC were diagnosed with CAC. The patients' records were analyzed retrospectively for duration of UC, prevalence of preoperative dysplasia, and other cancer risk factors (CRFs) (e.g., pancolitis, primary sclerosing cholangitis, early onset of UC, and backwash ileitis). The mean age of the patients at the time of cancer diagnosis was 43 years with an average UC duration of 15 years (6 patients had had UC less than 8 years). CAC was identified preoperatively by colonoscopy in 15 of 24 patients, with an additional 7 of 15 showing flat dysplasia. Five of nine patients without preoperatively diagnosed CAC had flat dysplasia. Overall, 19 patients had additional CRFs, most of them with at least two more CRFs. Despite a regular colonoscopic follow-up for most patients with UC, flat dysplasia was missed in 12 patients preoperatively. Therefore we suggest that patient information should also always include surgical options in each case where significant cancer risk factors are found.
Up until now, 2%-10% of colonic polyps larger than 2 cm have been considered colonoscopically unresectable. These were commonly treated by piecemeal resection and observation by colonoscopists and hemicolectomy by surgeons. Our minimally invasive "rural solution" in this situation is transcolonic resection through a mini-laparotomy. We present 7 patients with large colonic villous adenomas not amenable to colonoscopic resection. Laporoscopy determined the location of the muscle-splitting incision. The segment of bowel containing the polyp was exteriorized: antimesentric polyps were excised together with the corresponding colonic wall; polyps in mesenteric location were removed transmurally through an anterior colotomy. There was no surgical morbidity. Five of the 7 patients were discharged within 24 hours. Preoperative tattooing of the lesions and laparoscopic mobilization of the involved segment--when necessary--proved to be useful adjuncts. This seems to be an attractive option that may be superior to formal colectomy or repeated endoscopic piecemeal excision of large polyps. It provides colonoscopists with the option of avoiding having to resect very difficult polyps while not subjecting their patients to unnecessarily morbid operations.
Individuals with chronic ulcerative colitis are at increased risk of developing colorectal carcinoma, particularly if there is long-standing disease or extensive colitis. It is generally accepted that the risk of colorectal cancer does not begin until 8 to 10 years after the time of diagnosis of ulcerative colitis. Thereafter it increases by approximately 0.5% to 1.0% per year. In patients with Crohn's disease, the risk of malignancy is smaller and less well defined. The most significant predictor of the risk of malignancy in patients with inflammatory bowel disease is the presence of dysplasia in colonic biopsies. There is considerable controversy in the literature regarding the efficacy of colonoscopic surveillance programs and the role of prophylactic surgery to prevent colorectal cancer. Surveillance certainly fails to detect carcinoma in some patients who are having regular colonoscopy. Concerns have also been raised as to the cost-benefit of colonoscopic surveillance in patients with colitis. Randomized controlled trials of surveillance programs are highly unlikely in view of the low prevalence of IBD in the population, the long period of observation required, and the probability of contamination of surveillance programs by colonoscopy for assessment of disease activity. Despite the lack of clear guidelines, surveillance colonoscopy and biopsy continues to be widely practiced. Research is proceeding to identify genetic and biochemical markers that may prove clinically useful for predicting cancer risk. At present, however, surveillance programs are likely to continue according to institutional practice. It is important for those participating in such programs to be aware of the limitations of colonoscopy and biopsy as a means of reducing the risk of cancer in inflammatory bowel disease.
Because patients with ulcerative colitis have an increased long-term risk of colorectal cancer, colonoscopic surveillance with multiple biopsies is commonly performed for histopathological detection of dysplasia to select high-risk patients for prophylactic colectomy. Improved differentiation between neoplastic vs. nonneoplastic changes is needed because active inflammation may cause significant misinterpretation of nonneoplastic reactive/regenerative changes in the epithelium. We investigated whether the expression of proliferative antigens is correlated with various degrees of epithelial dysplasia and inflammatory changes in biopsy specimens from patients with long-standing ulcerative colitis. Colorectal biopsy specimens from patients undergoing colonoscopic surveillance were analyzed immunohistochemically using two types of monoclonal antibodies: MIB-1 against Ki-67 and NCL-PCNA against proliferating cell nuclear antigen for structural, active inflammatory, and dysplastic changes. Specimens from patients without inflammatory bowel disease or neoplasia were used as controls; these showed no increased proliferation. However, increased staining with the MIB-1 monoclonal antibody was detected in 9% of the specimens from patients with long-standing ulcerative colitis without active inflammation or dysplasia; this was significantly more common in specimens indefinite for dysplasia, probably positive (24%), and in those with definite dysplasia of low (47%) or high grade (67%; P = 0.008). For increased PCNA staining, there was a non-significant correlation (P = 0.30) with increasing degrees of dysplasia. Increased MIB-1 immunostaining was found in 50% and increased PCNA immunostaining in 75% of the specimens displaying mild inflammation. Both antibodies had a 100% increased staining in specimens with moderate or severe inflammation. Increased proliferation as expressed by MIB-1 is thus better correlated with increasing degree of dysplasia than is PCNA. Neither staining method is able to differentiate neoplastic from inflammatory epithelial changes. However, in the absence of active inflammation, immunostaining for MIB-1 may be a valuable adjunct in the confirmation of dysplastic epithelial changes in long-standing ulcerative colitis, particularly in the indefinite changes category.
BACKGROUND: The overall absolute risk of colorectal cancer (CRC) in longstanding extensive or total ulcerative colitis (UC) is estimated to be 10%-15%. The size of this risk is 6- to 10-times that expected in the background population. By performing complete colonoscopies with multiple biopsies from the entire colon and rectum at regular intervals, surveillance programmes for high-risk UC patients aim at detecting mucosal dysplasia in order to select CRC-prone individuals for prophylactic colectomy. MATERIAL AND METHODS: In many of the hitherto reported surveillance programmes, the UC patients surveyed have a much lesser risk of dying from CRC than do non-surveyed patients, although randomized studies are lacking. The inter- and intra-observer variability of dysplasia among pathologists is a major pitfall in the surveillance of these patients, as well as the influence of active inflammation, making dysplasia assessment difficult. The practical issues discussed here are, to a large extent, based on the recommendations from the Swedish Gastroenterological Association. RESULTS: Screening colonoscopy should be performed approximately 8-10 years after onset of disease. After negative results for screening or surveillance colonoscopy, the intervals between colonoscopies should not exceed 2 years. Biannual investigations of between 8 and 20 years' duration have been adopted in the Swedish studies, with annual colonoscopies from that point. Findings of CRC, a dysplasia-associated lesion or mass (DALM) with high-grade dysplasia (HGD) or low-grade dysplasia (LGD), or HGD in flat mucosa, are considered as indications for proctocolectomy, as well as repeated, confirmed findings of multifocal LGD. The management of unifocal LGD in flat mucosa is controversial (e.g. proctocolectomy or increased surveillance). Polyps may be handled with snare polypectomy. CONCLUSIONS: The safest way of handling UC patients at high risk of developing CRC is by performing regular colonoscopic surveillance. Dysplasia is a useful prognostic marker for subsequent cancer development but has its limitations. A combination of enhanced colonoscopic surveillance using markers that are more sensitive than dysplasia might be the optimal way to manage the increased CRC risk in these patients.
BACKGROUND: The aim of this study was to investigate the relation between clinical experience and performance with regard to colonoscopic procedures performed on the HT Immersion Medical Colonoscopy Simulator. The hypothesis is that the performance of novice, intermediate, and experienced operators is different on simulators, just as it is on real patients. METHODS: 25 Postgraduate doctors were recruited and divided into three groups according to their level of colonoscopic experience. Candidates were asked at random to perform colonoscopy on module 3 or 4 of the HT Immersion Medical Colonoscopy Simulator. Modules 3 and 4 have built-in complex loops, and can demonstrate the candidate's ability either to avoid or undo the loop. Candidates in the first group, termed "novice," each had performed fewer than 10 colonoscopies and included four preregistration house officers (PRHOs), five specialist trainee resistrars (SpRs) and two consultants. This novice group had completed 80 episodes among them. In the second group, termed "intermediate," each candidate had performed between 11 and 100 colonoscopies, and the candidates included five SpRs and two research fellows. This intermediate group had completed 65 episodes. Members of the third group, termed "experienced" each had performed more than 101 colonoscopies, and included one SpR and six consultants. This experienced group had completed 45 episodes between them. A time result of 3,600 s (1 h) was used to denote perforation. RESULTS: The experienced group were shown to perform better than the intermediate group, which in turn performed better than the novice group. The assessment was based on multiple factors including time taken to complete the test, percentage of the colonic mucosa visualized, incidence of colonic perforations, and path length used. The results were highly significant statistically for all these factors ( p < 0.000) except in path length used. CONCLUSIONS: This study demonstrated that operators who differ in terms of their clinical experience and technical ability also differ in their performance of simulated colonoscopy. Thus, the findings have shown the simulator technology to be a powerful discriminator of manipulative skills in colonoscopy. The clinical differences that exist between novices and experts in terms of experience and technical expertise in endoscopic procedures are reflected by statistically significant differences in performance on the simulator. It is therefore reasonable to argue that improving proficiency on the simulator may translate into improvements in clinical practice. This study has validated the use of the HT Medical Immersion Colonoscopy Simulator to discriminate among subjects with different levels of experience.
BACKGROUND: Repetitive tasks in the workplace are one cause of injury. This study aimed to identify injuries specific to physicians routinely performing colonoscopy, and to identify prevention strategies. METHODS: A survey was sent to all 2,173 worldwide members of the American Society for Colon and Rectal Surgery to investigate injuries or disabilities that resulted from performing colonoscopy and the methods used to prevent and alleviate symptoms related to the procedure. RESULTS: The response rate was 28%. Of the respondents, 96% performed colonoscopy. At least one injury or pain believed to result from performing colonoscopy was reported by 39% of the respondents. The most frequently reported injuries were to hands and fingers (n = 257), neck (n = 65), and back (n = 52). The methods adopted to alleviate injury included changing the height of the stretcher or video monitor, changing from a standing to a sitting position, minimizing torque on the colonoscope, having an assistant perform the torque maneuver, and resting or taking time off from colonoscopy. Two respondents also created devices to make the instrument more ergonomic. CONCLUSION: The number of colorectal surgeons encountering injury from colonoscopy highlights the need for preventive strategies. The study results suggest that it may be necessary to improve the design of colonoscopes to make them more ergonomic. Appropriate positioning of the endoscopist, patient, and monitors may diminish some of the injuries encountered.
BACKGROUND: The laparoscopic approach for the treatment of sigmoid volvulus has been a rare surgical indication. This phase 2 study investigated the feasibility and surgical outcomes of elective laparoscopic surgery for sigmoid volvulus. METHODS: Patients with sigmoid volvulus were first offered colonoscopic decompression for their acute colonic obstruction. If the colonic decompression was successful, complete bowel preparation was performed, followed by elective laparoscopically assisted sigmoidectomy. The details of the laparoscopic procedures are shown in the video. Briefly, the redundant sigmoid colon is totally mobilized by a laparoscopic medial-to-lateral dissection sequence, after which it is exteriorized, transected, and reconstructed by end-to-end anastomosis. In the authors' experience, the medial-to-lateral approach is highly efficient for the laparoscopic mobilization of the redundant sigmoid colon. We believe that the longer the lateral abdominal wall attachment of the sigmoid colon is preserved, the better the exposure and the easier the dissection. If the risk of anastomotic leakage is considered high in a specific case, protective ileostomy is selectively preformed. Before entering the current study, the patients were well informed about the advantages and disadvantages of laparoscopic surgery. The enrollment of patients was selective according to the appropriate eligibility criteria. This study was approved by the Institutional Review Board of the National Taiwan University Hospital. The patients' clinicopathologic data and surgical outcomes were prospectively evaluated. RESULTS: Between August 2001 and April, 2005, a total of 14 patients (10 men and 4 women) with sigmoid volvulus were treated with the described procedure. The age distribution of the patients was 68.4 +/- 12.2 years. The attack of sigmoid volvulus was the first episode for eight patients, the second episode for 4 patients, and the third episode (or more) for two patients. The body mass index (BMI) of the patients was 26.8 +/- 4.4 kg/m(2). The physical status (classification of American Society of Anesthesiology [ASA]) was 1 for five patients, 2 for eight patients, and 3 for 1 patient. During the laparoscopy, all the patients presented with the pathognomonic findings of sigmoid volvulus including redundant sigmoid colon, narrow sigmoid mesenteric pedicle, and mesosigmoiditis with mesenteric fibrosis and scarring, as shown in the video. The length of the resected colon was 32 +/- 6 cm. The operation time was 194.6 +/- 32.4 min, and the blood loss was 44.0 +/- 12.4 ml. The abdominal wound consisted of four 5 to 12 mm working ports and a 5 cm major wound for exteriorization of the sigmoid colon. Some surgeons have shown that a sigmoid volvulus can be resected through a 5-cm left lower quadrant incision with very little mobilization of the colon because of its redundancy. In this context, the laparoscopic approach competed with the minilaparotomy method in terms of adequate sigmoid resection, lysis of mesosigmoid adhesion, and tension-free colorectal anastomosis. Protective ileostomy was performed for the only patient with a physical status of ASA 3. There was no mortality in this case series. However, pneumonia developed postoperatively in one patient, acute myocardial infarction in one patient, and wound infection in two patients. Excluding the two patients who experienced postoperative pneumonia and acute myocardial infarction, the duration of the postoperative ileus was 48 +/- 12 h, the postoperative hospitalization was 7 +/- 1 days, and the degree of postoperative pain was 3.5 +/- 0.5 according to the visual analog scale. The return to partial activity required 18 +/- 2.5 days, and the return to full activity required 28.4 +/- 5.6 days. As compared with the overall costs for a conventional sigmoid colectomy, which are completely covered by the National Bureau of Health Insurance of Taiwan, the expenses for the patients undergoing laparoscopic procedures were significantly higher by approximately 24,000.0 NT dollars +/- 2,635.0 (1 U.S. dollar = 32 NT dollars). These higher expenses must be borne by the patients themselves. CONCLUSION: Considering that patients with sigmoid volvulus often are elderly and chronically ill, laparoscopic elective surgery after a successful colonoscopic decompression may be a good choice for a selected group of patients in terms of minimized surgical complications and quick convalescence.
BACKGROUND: The use of an endoloop may minimize the risk for bleeding after endoscopic polypectomy of large colorectal polyps. This study aimed to assess the safety and efficacy of colonoscopic ligation of the stalk of large pedunculated polyps by means of an endoloop technique, and to focus particular attention on the instances in which the use of this device was unsuccessful. METHODS: This study retrospectively evaluated attempted endoloop endoscopic polypectomy in 33 patients (19 men and 14 women; mean age, 62.5 years) with large pedunculated polyps. RESULTS: Application of the endoloop was impossible in four patients, and the snare became entangled with the loop in one patient. The remaining 28 patients underwent endoloop-assisted polypectomy. Bleeding occurred in four patients, either because the loop slipped of the stalk after polypectomy (2 patients) or because a thin stalk (< or = 4 mm) was transected by the loop before polypectomy (2 patients). CONCLUSION: Colonoscopic polypectomy with an endoloop may be safer than conventional polypectomy. The reasons for technical failure of this technique include a narrow left colon lumen, a thin stalk (< or = 4 mm), and close cutting in relation to the site of encirclement by the loop.
BACKGROUND: Although adenomatous polyps have been established clearly as precursor lesions for most cases of colorectal cancer, the role, if any, of hyperplastic polyps remains uncertain. The aim of the current study was to determine whether a patient with an index finding of hyperplastic polyp on colonoscopy is at increased risk for adenomatous polyps. METHODS: We conducted a retrospective cohort study using the records of a single surgeon's colonoscopic experience over a 20-year period (June 1973 to December 1994). Patients found to have hyperplastic lesions on index colonoscopy were compared with those who had "clean" index colonoscopies. The two groups were compared for the subsequent diagnosis of adenomatous polyps on follow-up colonoscopies. Those with cancer or adenomas at index colonoscopy or in their history were excluded. We used Cox proportional hazard modeling with subsequent adenoma or cancer diagnosis at follow-up colonoscopy as the outcome, controlling for age and gender. RESULTS: We identified 42 patients for whom hyperplastic polyps were the only colorectal neoplasms found on the index examination, in contrast to 362 control patients who had a "clean" index examination. In this cohort study, patients found to have only hyperplastic polyps on initial examination had a rate of subsequent adenoma diagnoses (42%) twice that of patients with a clean initial colonoscopy (21%). Mean follow-up time was 4.3 years. The relative rate ratio was 2.0 (95% confidence interval, 1.2-3.4). CONCLUSIONS: This study suggests that patients found to have hyperplastic polyps on initial colonoscopic examination may have twice the risk of adenomas on follow-up colonoscopy, as compared with those who have clean initial examinations. If this finding is borne out in larger prospective studies, surveillance strategies may need to be modified accordingly.
We present an unconventional approach to the management of a severe stricture with complete luminal obliteration after a coloanal anastomosis which was protected with a diverting loop ileostomy. The colonoscope was inserted in an antegrade fashion into the defunctionalized limb of the loop ileostomy and advanced to the level of the stricture. Under colonoscopic vision, a Kelly clamp was carefully introduced transanally through the stricture into the proximal lumen. The strictured anastomosis was then dilated with calibrated Hegar dilators. Periodic dilatations followed by closure of the ileostomy completed the management. The technique obviated the need for a more extensive surgical procedure.
A 25-year-old woman delivered her first-born child weighing 3400 g by full-term normal delivery. Bloody stool developed 3 days after delivery. Colonoscopic examination revealed two linear ulcers parallel to the anal column on the posterior side of the rectal ampulla about 5 cm from the anal ring. Coagulated blood was detected at the ulcer bottom, suggesting the site of hemorrhage. Bowel rest in the absence of oral intake resulted in the disappearance of bloody stool. Three days later colonoscopic examination revealed improvement in the ulcer. There was no sign of constipation. A lateral pelvic radiograph showed that the apex of the coccyx was flexed anteriorly. The parturient canal may have physically pressed the rectum against the apex of the coccyx during delivery, causing mucosal injury. Only a few studies have reported the complication of a rectal ulcer due to injury during delivery. Furthermore, none of the previous studies has reported a rectal ulcer caused by deformity of the coccyx.