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PubMed1976

Which colonic polyps should be excised endoscopically?

A review of 464 consecutive polypoid lesions of the colon reveals that virtually all pedunculated polyps and over 80% of 218 sessile polyps were removed colonoscopically. Although size or location of the lesions occasionally precludes colonoscopic excision, the endoscopic appearance of a sessile polyp is the most important factor in deciding upon the method of excision. In gneeral, smooth, soft, nonulcerated sessile lesions of all sizes were excised endoscopically, while approximately half of the larger (2-6 cm) firm, irregular-surfaced, benign sessile lesions, and all ulcerated or malignant sessile lesions required laparotomy for proper management. All polypoid lesions should be viewed endoscopically before deciding the method of excision, regardless of their size, location, or general appearnce by barium enema. Experience with endoscopic morphology and snare electrocautery technics was most important, since more than 85% of all polypoid lesions in this consecutive series were removed endoscopically.

Adenocarcinoma↗
PubMed2003

Computer-aided tumor detection in endoscopic video using color wavelet features.

We present an approach to the detection of tumors in colonoscopic video. It is based on a new color feature extraction scheme to represent the different regions in the frame sequence. This scheme is built on the wavelet decomposition. The features named as color wavelet covariance (CWC) are based on the covariances of second-order textural measures and an optimum subset of them is proposed after the application of a selection algorithm. The proposed approach is supported by a linear discriminant analysis (LDA) procedure for the characterization of the image regions along the video frames. The whole methodology has been applied on real data sets of color colonoscopic videos. The performance in the detection of abnormal colonic regions corresponding to adenomatous polyps has been estimated high, reaching 97% specificity and 90% sensitivity.

Adenomatous Polyps↗
PubMed2005

Mucosa-associated bacteria in ulcerative colitis before and after antibiotic combination therapy.

BACKGROUND: We proposed that Fusobacterium varium is one of the causative agents in ulcerative colitis. AIM: To examine the efficacy of antibiotic combination therapy against F. varium and to investigate the mucosa-associated bacteria before and after the therapy using a new molecular approach. METHODS: Twenty patients with ulcerative colitis were randomly assigned into the antibiotic treatment group (amoxicillin, tetracycline and metronidazole for 2 weeks) and no-antibiotics group. Clinical assessment, colonoscopic and histological evaluations were performed at 0 and 3-5 months after the treatment. DNA from mucosal bacteria was isolated from biopsy specimens. We investigated the mucosa-associated bacterial components by terminal restriction fragment length polymorphism with the restriction enzyme HhaI and MspI, and quantified the change in the number of bacteria by real-time polymerase chain reaction. Immunohistochemical detection of F. varium in biopsy specimens was also performed. RESULTS: After the treatment, the clinical assessment, colonoscopic and histological scores improved in the antibiotic group compared with the control group. Three peaks of terminal restriction fragment length polymorphism decreased after treatment only in the antibiotic group. Eubacterium rectale, Dorea formicigenerans, Clostridium clostridioforme and F. varium were included in these peaks. Based on the real-time polymerase chain reaction study, only F. varium was significantly reduced after treatment. In the immunostaining, post-treatment scores in treatment group were significantly lower than that in control group. CONCLUSIONS: Antibiotics combination therapy was effective for ulcerative colitis. The number of mucosa-associated F. varium significantly decreased after the treatment.

Amoxicillin↗
PubMed2006

Extended flexible sigmoidoscopy performed by colonoscopists for colorectal cancer screening: a pilot study.

BACKGROUND: Caecal intubation can be achieved by extended flexible sigmoidoscopy in 32% of patients. AIM: To assess the feasibility of extended flexible sigmoidoscopy performed by colonoscopists for colorectal cancer screening. METHODS: We enrolled 41 patients referred for screening flexible sigmoidoscopy. After purging, examination was performed with a colonoscope. All patients completed sigmoidoscopy (success in meeting referral goal); 93% and 71% had examination to the transverse or ascending colon, and caecum, respectively. Overall yield and right-sided polyps was 56% and 27%, respectively. Caecal intubation and complete examination with polypectomy took 6.0 +/- 2.5 and 18.3 +/- 5.1 min, respectively; with no complications. Twelve patients requested colonoscope withdrawal because of discomfort. Although 46% reported moderate to severe discomfort, 39% and 36%, respectively, were definitely or probably willing to repeat flexible sigmoidoscopy. RESULTS: Unsedated colonoscopy introduced as extended flexible sigmoidoscopy emphasizes the benefits of added yield rather than the negative image of withholding of discomfort relief. The patient can choose to accept the equivalent of an unsedated colonoscopy or reject the option based on perceived discomfort during extended flexible sigmoidoscopy performed by the colonoscopist. CONCLUSION: Extended flexible sigmoidoscopy is a feasible option in carefully selected patients, fully prepared and by an experienced colonoscopist.

Cecum↗
PubMed1987

Lectin and mucin histochemistry as an aid to cancer surveillance in ulcerative colitis.

In a preliminary study, we assessed 10 lectins for the identification of dysplasia in colectomy specimens from patients with ulcerative colitis. Peanut agglutinin (PNA) binding was found in all cases of dysplasia. In the main study the relationship between PNA staining, high iron-diamine/alcian blue (HID-AB) histochemistry, and dysplasia was investigated in 115 pre-operative colonoscopic biopsies and the subsequent resection specimens from patients with ulcerative colitis complicated by carcinoma (n = 6) and patients undergoing proctocolectomy for failure of medical management (n = 8). Peanut lectin was of no value in the assessment of pre-malignant changes or cancer risk. However, the HID-AB stain appears to clarify the interpretation of less severe pre-malignant changes and may be usefully applied to the interpretation of colonoscopic biopsies for cancer surveillance in ulcerative colitis.

Alcian Blue↗
PubMed1991

Colonic epithelial dysplasia or carcinoma in a regional group of patients with ulcerative colitis of more than 15 years duration.

Colonoscopic screening for neoplasia was performed in a regional group of ulcerative colitis patients with a disease duration of greater than or equal to 15 years. A total of 121 patients, aged less than 80 years, were invited to participate, of whom 100 (83%) accepted colonoscopy, including biopsies in 15 standard locations of the entire colon, plus additional biopsies from all visible lesions. Unequivocal dysplasia was found in one patient with extensive colitis and a disease duration of 31 years. A polyp with highly differentiated adenocarcinoma was found in the sigmoid colon of a patient with intermittent rectum involvement, 37 years after the ulcerative colitis diagnosis had been made. Biopsy specimens from the remaining 98 patients showed no signs of dysplasia or cancer. Thus the frequency of pre-malignant or malignant changes is very low compared with the results of similar studies, and the rationale for general colonoscopic surveillance programmes for such patients is open to question.

Adenocarcinoma↗
PubMed2006

Less patient discomfort by one-man colonoscopy examination.

A randomised prospective trial compared safety and patient tolerance for one-man method with two-man method undergoing colonoscopy. Eighty patients were randomized to 1 of 2 groups: the two-man method group (n = 40); or the one-man method group (n = 40). All colonoscopic examinations were performed by the same endoscopist to reduce skill-based variation. Patient tolerance for colonoscopy was evaluated with a numerical rating scale ranging from 0 for painless to 5 for maximal pain. Cardiopulmonary parameters were recorded during the procedure. Patients receiving one-man method had lower pain score than two-man method. The length of the scope reach to the cecum was shorter in the one-man group than the two-man group. The patients underwent two-man colonoscopy had higher maximum increase in heart rate during the procedure compared with one-man group. One-man colonoscopy can improve patient tolerance and reduces patient pain by decreasing the redundancy of colonoscope during the procedure.

Adolescent↗
PubMed1986

Anaesthesia for colonoscopy. An examination of the anaesthesia as an element of risk at colonoscopy.

The importance of anaesthesia as an element of risk at colonoscopy has been examined retrospectively over a 10-year period from 1975 to 1984. The colonoscopic examinations were made by surgical gastroenterologists and anaesthesiologists working in cooperation. In 1242 cases the patients received diazepam/fentanyl anaesthesia during the colonoscopy (Group I) and in 126 cases they received general anaesthesia (Group II). The incidence of perforations of the large bowel in Group I was 0.8% (95% confidence limits: 0.4-1.5%) and in Group II 0.0% (95% confidence limits: 0.0-2.9%). Statistically the difference is not significant (P = 0.38). The groups were comparable with a view to the patients' age, weight, the duration of the colonoscopy and the number of times that polypectomy had been performed. All anaesthesia was administered by staff qualified by training and experience to administer anaesthesia, and did not cause any complications. However, four patients had vasovagal reflexes due to manipulation of the colonoscope. The dosing in the patients in Group I averaged: diazepam as premedication 9.2 mg, intravenous diazepam 12.4 mg, intravenous fentanyl 0.14 mg, and the duration of the colonoscopy was 36.5 min. The medication and the duration of the colonoscopy did not vary significantly in the patients with perforation of the large bowel. Our conclusion is that diazepam/fentanyl anaesthesia, administered by experienced staff, is harmless, and that general anaesthesia for colonoscopy did not involve an increased risk of perforation of the large bowel.

Aged↗
PubMed2006

Rectal guiding tube to facilitate distal colonic stent insertion.

Self-expanding metallic stents for the treatment of acute colonic obstruction is a recent technique showing promising results. Traditionally metallic stents have used a colonoscope as the portal for stent insertion. Our rectal guiding tube has been devised to enable continuous opacification of the colon without contrast or colonic content leakage and provide a rigid portal through which to insert the metallic stent safely. In many situations concomitant use of a colonoscope is not necessary, especially in left-sided or more distal colonic lesions.

Colonic Diseases↗
PubMed1996

Epithelial cell proliferation during colonic chemical carcinogenesis in the rat.

To define the significance of alterations in epithelial cell proliferation as a marker of high risk mucosa for colorectal cancer, we examined cell proliferative events in the colonic mucosa during chemical carcinogenesis using in vitro bromodeoxyuridine labelling and by analysing serial colonoscopic biopsy specimens from dimethylhydrazine (DMH)-treated rats. In both the rectum and flexure of the colon, an increased labelling index of colonic epithelial cells, an upward extension of the proliferating zone and an upward shift of the major area of DNA synthesis of epithelial cells were observed during DMH-induced colonic carcinogenesis in rats. These changes preceded the development of the colonic tumour and were observed in endoscopically normal rectal mucosa where the tumour was absent. We confirmed the altered cell proliferative events preceding the development of the tumour by examining serial colonoscopic biopsies. The results suggest that these alterations are features that identify premalignant colonic mucosa in DMH-treated rats.

Animals↗
PubMed2006

Factors predicting successful outcome following neostigmine therapy in acute colonic pseudo-obstruction: a prospective study.

AIM: To evaluate predictors of neostigmine response in patients with acute colonic pseudo-obstruction. METHODS: Twenty-seven patients with acute colonic pseudo-obstruction were enrolled in the study. All patients had received initial conservative management such as nil orally, nasogastric suction, rectal tube placement and correction of electrolyte imbalance for the first 24 h. Those who did not resolve with conservative management received 2 mg neostigmine intravenously. The same dose was repeated after 24 h in patients who did not response to the first dose (initial non-responders), or in those patients who relapsed after an initial response (initial responders). All non-responders to neostigmine underwent colonoscopic decompression followed by 2 mg neostigmine infusion for 30 min. A sustained response was defined as the resolution of symptoms and colonic dilatation on a plain radiograph. RESULTS: The study enrolled 27 patients; 18 were male (67%), and the median age was 60 years (range 18-78 years). Eight (30%) patients had spontaneous resolution. Initial response with neostigmine was observed in 16 (84%) patients, of which 10 (63%) had a sustained response. Nine patients (three initial non-responders and six initial responders) had received a second dose of neostigmine. A sustained response was seen only in five initial responders. Four patients who did not respond to neostigmine underwent colonoscopic decompression followed by neostigmine infusion and had a sustained response. Neostigmine responders were more likely to be postoperative patients (11 of 15 (73%) vs one of four (25%), P = 0.07), less likely to have electrolyte imbalance and to be on antimotility agents (three of 15 (20%) vs four of four (100%), P = 0.009 and two of 15 (13%) vs four of four (100%), P = 0.003). CONCLUSIONS: Electrolyte imbalance and usage of anti-motility agents are factors associated with a poor response, while postoperative patients showing good response to neostigmine therapy.

Acute Disease↗
PubMed2004

High-tech rural clinics and hospitals in Japan: a comparison to the Japanese average.

CONTEXT: Japanese medical facilities are noted for being heavily equipped with high-tech equipment compared to other industrialised countries. Rural facilities are anecdotally said to be better equipped than facilities in other areas due to egalitarian health resource diffusion policies by public sectors whose goal is to secure fair access to modern medical technologies among the entire population. OBJECTIVES: To show the technology status of rural practice and compare it to the national level. DESIGN: Nationwide postal survey. SETTING, SUBJECTS & INTERVENTIONS: Questionnaires were sent to the directors of 1362 public hospitals and clinics (of the 1723 municipalities defined as 'rural' by four national laws). Information was collected about the technologies they possessed. The data were compared with figures from a national census of all hospitals and clinics. RESULTS: A total of 766 facilities responded (an effective response rate of 56%). Rural facilities showed higher possession rates in most comparable technologies than the national level. It is noted that almost all rural hospitals had gastroscopes and colonoscopes and their possession rates of bronchoscopes and dialysis equipment were twice as high as the national level. The discrepancy in possession rates between rural and national was even more remarkable in clinics than in hospitals. Rural clinics owned twice as many abdominal ultrasonographs, and three times as many gastroscopes, colonoscopes, defibrillators and computed tomography scanners as the national level. CONCLUSIONS: Rural facilities are equipped with more technology than urban ones. Government-led, tax based, technology diffusion in the entire country seems to have attained its goal. What is already known on this subject: As a general tendency in both developing and developed countries, rural medical facilities are technologically less equipped than their urban counterparts. What does this paper add?: In Japan, rural medical facilities are technologically better equipped than urban facilities.

Ambulatory Care Facilities↗
PubMed2006

Appropriateness of colonoscopy using the ASGE guidelines: experience in a large Asian hospital.

BACKGROUND: The is currently a heavy burden on endoscopy services worldwide and although guidelines for the appropriate use of esophagogastroduodenoscopy (EGD) have been well studied, there are few such studies with respect to colonoscopy and none for the Asia-Pacific region. This study aimed, firstly, to determine the 'appropriateness of colonoscopy' for procedures performed in the endoscopy unit of a large Asian hospital using the American Society of Gastrointestinal Endoscopy (ASGE) 2000 guidelines, and secondly, to determine predictive factors including 'appropriateness of colonoscopy' for positive findings and colorectal cancer (CRC). METHODS: A prospective cross-sectional study was carried out on consecutive colonoscopies performed in the University of Malaya Medical Center. The unit has an open-access endoscopy policy for doctors who work in the hospital. Referrals were from endoscopists (gastroenterologists and surgeon-endoscopists), primary care physicians and other specialists. The indication of a procedure referral was recorded and judged 'appropriate' or 'inappropriate' using the ASGE criteria. The colonoscopic findings were recorded and classified as positive (endoscopies showing any pathology that had direct therapeutic or prognostic consequences) or negative findings (endoscopies showing no pathology or minor pathologies). Predictive factors for positive findings and CRC were determined using multivariate analysis. RESULTS: Of 380 patients referred for colonoscopy, 220 (57.9%) were classified as appropriate according to the ASGE guidelines, and 49 (12.9%) as inappropriate. The remaining 111 patients (29.2%) presented with complaints and conditions that could not be categorized. The rate of appropriate referral was similar for all three categories of physician (endoscopists: 59.8%, primary care physicians: 48.1%, others: 51.1%). When referrals by endoscopists were substratified according to gastroenterologists and surgeon-endoscopists, the rate of appropriate referral among gastroenterologists (78.4%) was significantly higher than that of surgeon-endoscopists (56.1%) (P = 0.049), primary care physicians (P = 0.013) and 'others' (P = 0.009). The most common appropriate indications were unexplained Rectalbleeding (79 cases, 20.8%) followed by CRC surveillance (45 cases, 11.8%). The most common inappropriate indication was inappropriately timed colonic cancer surveillance (32 cases, 8.4%). Chronic constipation in 36 cases (9.5%) was the most common 'unlisted' indication. A positive colonoscopic finding was detected in 131 (34.5%) examinations and CRC was found in 36 patients (9.5%). Appropriateness of indication was not a predictive factor for positive findings or CRC and there was no difference in the proportion of cases with positive findings or CRC in the three 'appropriateness categories'. Multivariate analysis revealed that only Rectalbleeding and smoking were significant independent positive predictive factors for positive findings and CRC. CONCLUSION: The appropriateness of colonoscopy was not high among the different sources of referrals except for the subgroup of 'gastroenterologist'. Furthermore, the rates of positive findings and CRC among the cases with appropriate, inappropriate and unlisted indications did not differ. The ASGE guidelines will need to be modified for Asia to be of practical use.

Adult↗
PubMed1991

Adenoma-carcinoma sequence of the large bowel.

Fifty-two surgically removed large bowel specimens and 3 colonoscopically removed polyps with mucosal carcinomas were studied. Among 36 frank colorectal carcinomas, six (17%) had a focus of adenomatous remnant. The average size of carcinomas without adenomatous remnant was 56.0 mm and of those with adenomatous remnant was 44.3 mm. Four (67%) of 6 submucosal carcinomas and all of 4 mucosal carcinomas showed an adenomatous remnant. The average size of submucosal carcinomas was 17.7 mm and that of mucosal carcinomas was 16.3 mm. The smaller and less advanced the carcinoma, the more likely it was to show an adenomatous remnant, suggesting that carcinomas arise in adenomas and destroy surviving benign tumour as they grow. Coexisting adenomas were seen in 19 of 46 neoplasm-bearing patients (41%) and 1 of 9 patients (11%) without neoplasms. Average sizes of adenomas with moderate and mild atypia were 13.0 mm and 8.2 mm respectively, which were smaller than the sizes of submucosal and mucosal carcinomas. Although the numbers were small, these findings support the concept of adenoma-carcinoma sequence. Twenty-one flat elevations were collected during the study. Ten were neoplasm (9 adenomas and an early carcinoma), ten were metaplastic polyps and one was a histologically normal mucosal protrusion. The atypism of 10 flat adenomas increased with increasing size, as with ordinary adenomas. As 10 of 55 adenomas (18.2%) were flat adenomas, which are difficult to detect during routine colonoscopic examination, colonoscopists should make every effort to discover flat adenomas, which seem to play an important role in the adenoma-carcinoma sequence.

Adenoma↗
PubMed1995

Colonoscopy: how far is enough?

Total colonoscopy is arguably the best method available for examination of the colon and rectum. Colonoscopy costs are high and rising and it may be that in the future practitioners will be unable to afford to colonoscope all of the patients presently being examined. This retrospective study was undertaken in an attempt to examine the cost, in terms of lesions missed, of a limited endoscopy programme. During a 15 year period, 1426 colonoscopies were performed at Wellington Hospital, New Zealand. Total colonoscopy was possible in 79% of all patients. Three perforations occurred. Nine patients bled and two required blood transfusion after biopsy or 'snaring' of polyps. After exclusion of patients with continuous inflammatory bowel disease (IBD) 75% of all lesions were found in or distal to the descending colon. More cancers were found in patients colonoscoped because of bleeding. Thirty-two of 93 cancers diagnosed were proximal to the descending colon but 18 presented with bleeding. A further seven had a radiological abnormality. Only 7.5% of colorectal cancers would be missed by flexible sigmoidoscopy (65 cm) and 75% of the costs of total colonoscopy would be avoided if only patients presenting with bleeding and IBD were offered total colonoscopy and patients with radiological abnormalities were treated according to the abnormality. This compromise, based on the data presented, may represent a rational way to reduce colonoscopy costs.

Colonic Neoplasms↗
PubMed1998

Management of colonic lipomas.

BACKGROUND: Little is known of colonic lipomas, especially in an Asian population, and their management is controversial. METHODS: A computerized colonoscopy database was analysed and patients with colonic lipomas were reviewed. RESULTS: There were 16 colonic lipomas (incidence of 0.15%) in a series of 10658 consecutive colonoscopies. There were seven men and nine women, with a mean age of 61.8 years (range: 28-80 years). The size of the lipomas ranged from 1.5 to 6 cm; all those larger than 3.5 cm were symptomatic (P = 0.05). The most common symptom was mild bleeding per rectum. Right-sided lipomas were palpable while left-sided lipomas presented with obstructive symptoms. Colonoscopic removal by hot biopsy or snare polypectomy was possible where the lipomas were 2.5 cm and pedunculated. Surgery was performed in six patients (four open, two laparoscopic) for symptoms and to exclude malignancy. There was no morbidity or mortality. CONCLUSIONS: Small or pedunculated lipomas may be safely removed colonoscopically and the diagnosis confirmed histologically. Larger lipomas require surgical resection for relief of symptoms or to exclude malignancy.

Adult↗
PubMed1976

Colonoscopy in the management of diseases of the colon and rectum.

This report covers a 2.5-year experience with colonoscopy in the management of 208 patients (104 men and 98 women, average age 58 years). Colonic bleeding of unknown cause and abnormal barium-enema findings were the most common indications for colonoscopic examination. During this period, 110 colonoscopic polypectomies were performed. Among the few complications was one case of perforation of the sigmoid from transcolonoscopic removal of a small carcinoma; the perforation was incidentally discovered at the time of subsequent laparotomy. Bleeding occurred in 6 patients, but only one of them required surgical intervention to arrest the hemorrhage. Colonoscopy is a safe, effective and reliable diagnostic and therapeutic procedure. Its use can reduce expense for the patient and obviate a long painful postoperative period.

Adult↗
PubMed1998

Intestinal tuberculosis: clinicopathologic analysis and diagnosis by endoscopic biopsy.

OBJECTIVES: Tuberculosis is still an important cause of granulomatous colitis in developing countries. If we can diagnose tuberculosis using endoscopic biopsy material, clinicians can avoid invasive diagnostic procedures and needless operations. For this purpose, we evaluated clinical manifestations, pathological findings, and diagnostic methods in endoscopically biopsied intestinal tuberculosis patients. METHODS: From January 1991 to December 1996, 42 patients with intestinal tuberculosis were endoscopically examined and tissue culture, immunohistochemical stain, Ziehl-Neelsen stain, and polymerase chain reaction in fresh and fixed tissue were applied. The pathological findings were analyzed and compared with the results of the other diagnostic methods. RESULTS: In tuberculosis patients, transverse ulcers with surrounding hypertrophic mucosa and multiple erosions were usual colonoscopic findings. The granulomas were found in 74% of the cases. The positivity ranged from 30-45%. There were no significant differences in the positivity among those diagnostic methods (p > 0.05). The positivity of Ziehl-Neelsen stain in fixed tissue was higher in the group having granulomas and it was reversed in PCR (p < 0.05). The increasing number of biopsy particles raised the positivity of Ziehl-Neelsen stain and PCR in fixed tissue (p < 0.05). CONCLUSIONS: Transverse ulcers were the most characteristic colonoscopic finding and granulomas were frequent pathological findings in intestinal tuberculosis. Higher positivity and reliable results were found in tissue culture, Ziehl-Neelsen stain, and polymerase chain reaction. To increase the diagnostic rate, the endoscopist should take enough tissue and deep biopsy material from ulcer bases and diseased mucosae.

Adolescent↗