SEARCH · PubMed Health

Results for “Colonoscopy”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 757 records · Page 42Linked to original sources

PubMed2001

Virtual colonoscopy: a novel imaging modality for colorectal cancer.

Advances in computed tomography (CT) technology and computer capabilities have contributed to the development of a new imaging modality for colorectal lesions called CT colonography or virtual colonoscopy. Virtual colonoscopy is a rapid, minimally invasive scan of the cleansed and distended colon. Early work has demonstrated that this test is safe and well tolerated, and that it may be sensitive and specific enough to identify most significant precancerous or cancerous lesions. A number of technical and practical problems remain before virtual colonoscopy can be applied at a population level.

Colonoscopy↗

PubMed1984

Colonoscopy as a routine preoperative procedure for carcinoma of the colon.

Ninety patients with cancer of the colon who had total colonoscopy in the perioperative period have been reviewed. Almost half of the examinations revealed positive findings, three being unsuspected synchronous carcinomas in an area that would not have been resected with the proposed primary cancer. In addition, 79 polyps in 36 patients, the majority of which were also undetected by barium enema, were found and removed at colonoscopy. Thus, patients with carcinoma of the colon, in view of its tendency to be associated with synchronous polypoid disease, should have colonoscopy in the perioperative period. Whenever possible, this should be carried out preoperatively to confirm the diagnosis, to remove suspected or unsuspected polyps, and to detect unsuspected synchronous carcinoma.

Adenocarcinoma↗

PubMed1986

Routine colonoscopy in the management of colorectal carcinoma.

A prospective study of the role of preoperative and routine follow-up colonoscopy in 75 patients with colon and rectal carcinoma disclosed that additional premalignant or malignant lesions were detected and successfully treated in 44 percent of patients. These included four synchronous and three metachronous carcinomas. Timely diagnosis and treatment of such tumors and secondary prevention of metachronous carcinomas by polypectomy is a major identifiable benefit of close follow-up examinations of these patients. No other test compares favorably with colonoscopy in this regard. These data support the conclusion that colonoscopy should be performed routinely preoperatively and every 6 to 12 months after colectomy for carcinoma.

Aged↗

PubMed1992

Can general surgeons perform colonoscopy safely?

The purpose of the current study was to review the safety of colonoscopy performed by nonfellowship-trained general surgeons. To address this issue, we reviewed more than 1,000 consecutive diagnostic and therapeutic colonoscopies and recorded the complications. This was a multi-institutional study involving seven general surgeons, none of whom had had formal fellowship endoscopic training. Perforation was confirmed by laparotomy, bleeding was defined as that requiring hospitalization and/or transfusion, and cardiopulmonary arrest was self-explanatory. There was one perforation in the diagnostic group and none in the therapeutic group, for a rate of 0.10% overall and 0.12% in diagnostic colonoscopy. There were no instances of bleeding or cardiac arrest. This complication rate of 1 per 1,025 colonoscopic procedures by general surgeons compares favorably with that previously reported by other specialties (p less than 0.001). We conclude that postgraduate endoscopy fellowship is not necessary for general surgeons to become safe colonoscopists.

Clinical Competence↗

PubMed1991

Screening colonoscopy in asymptomatic average-risk persons with negative fecal occult blood tests.

Colonoscopy was performed on 210 asymptomatic average-risk persons, aged 50-75 years, who had negative fecal occult blood test results. Colonoscopy was complete to the cecum in 209 subjects. Fifty-three subjects (25%) had adenomas and two had cancer. All of the adenomas greater than or equal to 1 cm in size and both cancers occurred in subjects aged greater than or equal to 60 years. Fifty-one percent of subjects with adenomas and one with cancer had no neoplasms distal to the sigmoid-descending colon junction. One subject had a major postpolypectomy hemorrhage that stopped spontaneously. Screening colonoscopy, therefore, has a high yield for detection of neoplasms in asymptomatic average-risk persons aged greater than or equal to 60 years with negative fecal occult blood test results. The yield is low in persons aged 50-54 years and intermediate in persons aged 55-59 years.

Adenoma↗

PubMed2006

The corner of the gastroenterologist: what colonoscopy can do, what to ask to radiologist.

Colonoscopy is the diagnostic technique of choice for most colonic diseases and allows to explore the entire colonic mucosal surface and to visualize the mucosa of terminal ileum. When it is done with appropriate indications, significantly more clinically relevant diagnoses are made. Moreover, colonoscopy keeps an operative role in the treatment of some acute and chronic colonic diseases and it is the most effective colorectal cancer screening modality. The endoscopic exploration of colon is not infallible and presents rare complications. Programs of endoscopic training and practice, monitoring of quality indicators and continuous technological development are improving endoscopic diagnostic and therapeutic role. Appropriate indications for colonoscopy, its limits and complications and questions for the radiologist are discussed.

Clinical Competence↗

PubMed2006

Conventional colonoscopy: technique, indications, limits.

Colonoscopy has long been the gold standard for the diagnosis of colonic diseases. Recently, with the advent of CT colonografy, new alternatives seem to appear on the horizon, which seem to finally overcome some of colonoscopy's drawbacks like procedure related pain and discomfort during the examination. Polyp miss rate and the fact that not always the caecum can be reached are also the basis of debate. This article gives an overview about current technique, indications and limitations of diagnostic colonoscopy as well as a potential prospect for the future, discussing novel imaging technologies ranging from magnification endoscopy to virtual histopathology.

Colonic Diseases↗

PubMed2005

A comparison of the immunochemical fecal occult blood test and total colonoscopy in the asymptomatic population.

BACKGROUND & AIMS: The fecal occult blood test (FOBT) is recommended as a screening test for colorectal cancer, but there are few reliable studies on the accuracy of immunochemical FOBT. The aim of this study was to analyze the sensitivity of immunochemical FOBT and to compare the results with the findings from complete colonoscopy. METHODS: Asymptomatic adults underwent 1-time immunochemical FOBT and total colonoscopy simultaneously. The prevalence and location of colorectal neoplasia were determined by colonoscopy. The results of immunochemical FOBT and the colonoscopic findings were compared. RESULTS: Of 21,805 patients, immunochemical FOBT was positive in 1231 cases (5.6%). The sensitivity of 1-time immunochemical FOBT for detecting advanced neoplasia and invasive cancer was 27.1% and 65.8%, respectively. In addition, the sensitivity for invasive cancer according to Dukes' stage showed 50.0% for Dukes' stage A, 70.0% for Dukes' stage B, and 78.3% for Dukes' stages C or D. The sensitivity for detecting advanced neoplasia at the proximal colon was significantly lower than that detected in the distal colon (16.3% vs 30.7%, P = .00007). CONCLUSIONS: Although the screening of asymptomatic patients with immunochemical FOBT can identify patients with colorectal neoplasia to a certain extent, the sensitivity is relatively low and different according to the tumor location. Therefore, programmatic and repeated screening by immunochemical FOBT may be necessary to increase sensitivity for colorectal cancer detection.

Adult↗

PubMed2006

Colorectal neoplasia in Asia: a multicenter colonoscopy survey in symptomatic patients.

BACKGROUND: The incidence of colorectal cancer is rising rapidly in some Asian countries. OBJECTIVE: To determine the prevalence and the distribution of colorectal neoplasm in Asian populations. DESIGN: A multicenter colonoscopy survey. PATIENTS: Between July 2004 and April 2005, consecutive symptomatic patients undergoing colonoscopic examinations in 10 different Asian countries. SETTING: The location and the histologic features of all colonic neoplasms were recorded. Advanced neoplasm was defined as adenoma larger than 10 mm in size, with >25% villous features or with high-grade dysplasia or invasive carcinoma. MAIN OUTCOME MEASUREMENTS: The prevalence and the distribution of colorectal neoplasm and advanced neoplasm. RESULTS: A total of 5464 eligible patients underwent colonoscopy. Advanced neoplasm was found in 512 patients (9.4%). Factors associated with the presence of advanced neoplasm in this symptomatic Asian population included male sex (relative risk [RR] 1.52, 95% confidence interval [CI] 1.26-1.84), older age (RR 1.05, 95% CI 1.04-1.06), and ethnicity (P = .001). Advanced proximal neoplasm was detected in 136 patients (2.5%); 83 (61.0%) of the patients had normal distal colon. The RR of proximal advanced neoplasm was 2.5, 95% CI 1.7-3.7 in those with any adenoma in the distal colon compared with those with normal distal colon. LIMITATIONS: Possible underrepresentation of some ethnic groups because of uneven ethnic group distribution and the lack of population-based registry. CONCLUSIONS: This was the first multicenter colonoscopy survey that examined the characteristics of colorectal neoplasm in Asia. The results will have important implications on the planning for future colorectal cancer screening in this region.

Adenoma↗

PubMed2005

Practical uses of chromoendoscopy and magnification at colonoscopy.

New technologies in the form of high-magnification or zoom colonoscopy complemented by chromoscopic agents permits early detection of neoplastic colorectal lesions, particularly flat and depressed types. Establishing suitability for endoscopic resection or surgical excision can be enhanced using these techniques. Chromoscopic colonoscopy may play an important role in the routine endoscopic colorectal cancer surveillance programs in patients assuming a high risk of colorectal neoplasia. This article summarizes recent data regarding the prevalence and histopathologic characteristics of flat and depressed colorectal lesion in Western cohorts and describes how their detection and management can be improved by chromoscopy and magnification technology. The techniques required for chromoscopic colonoscopy and magnification imaging are outlined along with a review of the literature on these subjects.

Adenoma↗

PubMed2005

The role of early colonoscopy in CMV colitis of transplant recipients.

Cytomegalovirus (CMV)-associated diseases remain a major problem in transplant recipients. Early diagnosis is critical. Presentation of early CMV colitis can be mild and nonspecific in transplant recipients. Although serology is helpful in the diagnosis, sometimes it is inadequate. Because the endoscopic features of CMV colitis are specific, colonoscopy facilitates the histopathologic examination. We present the clinical properties and advantages of early colonoscopy in transplant recipients with CMV colitis. The study group included seven patients (six men, one woman of mean age, 36.7 years (range, 22 to 64 years) whose mean transplant duration was 12.3 months (range, 1 to 72 months). Six of the seven patients experienced an acute graft rejection treated with high doses of steroids; one patient had a herpes simplex virus infection. All patients were on steroid treatment with a various combinations of immunosuppressive agents, including cyclosporine, mycophenolate mofetil, and tacrolimus. All patients presented with mild diarrhea without any blood or mucous discharge. Four patients had fever exceeding 38 degrees C; two had abdominal pain. Stool examinations revealed normal findings in six patients, while one patient had white blood cells and amoebic cysts. Serum CMV IgM and CMV pp65 antigenemia were negative in five of seven patients and two had positive results. All patients showed typical colonoscopic and histopathologic findings compatible with CMV colitis. Standard ganciclovir treatment was successful in all patients. Early and rapid colonoscopy is beneficial for the early diagnosis and management of CMV colitis in transplant recipients.

Adult↗

PubMed1999

Is upper gastrointestinal endoscopy indicated in asymptomatic patients with a positive fecal occult blood test and negative colonoscopy?

PURPOSE: There are no recommendations as to whether endoscopic evaluation of the upper gastrointestinal tract is indicated in asymptomatic patients who have a positive fecal occult blood test and a negative colonoscopy. SUBJECTS AND METHODS: All asymptomatic patients with a positive fecal occult blood test who were referred for diagnostic endoscopy were identified. Patient charts, endoscopy records, and pathology reports were reviewed. RESULTS: During the 5-year study period, 498 asymptomatic patients with a positive fecal occult blood test and negative colonoscopy were evaluated. An upper gastrointestinal source of occult bleeding was detected in 67 patients (13%), with peptic ulcer disease being the most common lesion identified (8%). Four patients were diagnosed with gastric cancer and 1 had esophageal carcinoma. In addition, 74 patients (15%) had lesions that were not considered a source of occult bleeding; these findings prompted a change in management in 56 patients (11%). Anemia was the only variable significantly associated with having a clinically important lesion identified (multivariate odds ratio = 5.0; 95% confidence interval 2.9 to 8.5; P <0.001). CONCLUSIONS: Upper gastrointestinal endoscopy yields important findings in asymptomatic patients with a positive fecal occult blood test and negative colonoscopy. Our data suggest that endoscopic evaluation of the upper gastrointestinal tract should be considered, especially in patients with anemia.

Aged↗

PubMed1998

Yearly colonoscopy, liver CT, and chest radiography do not influence 5-year survival of colorectal cancer patients.

BACKGROUND & AIMS: Guidelines on the type and frequency of follow-up of patients after curative surgery for colorectal cancer are unclear. The aim of this study was to determine the survival benefit of a planned follow-up program. METHODS: Three hundred twenty-five patients who underwent curative resection of colorectal cancer were prospectively randomized to either intensive or standard follow-up. After stratification according to Dukes' stage and site in the colon or rectum, patients were randomized to intensive follow-up of yearly colonoscopy, computerized tomography (CT) of the liver, and chest radiography and clinical review and simple screening vs. structured clinical review and simple screening tests only. RESULTS: On completion of 5-year follow-up, there was no significant difference in survival between the two groups. Yearly colonoscopy failed to detect any asymptomatic local recurrences. Only one asymptomatic curable metachronous colon tumor was detected. Liver CT resulted in earlier detection of hepatic metastases but did not increase the number of curative hepatectomies. Only 1 patient had an asymptomatic CT-detected liver metastasis, and another had an asymptomatic chest radiography-detected lung metastasis. Both had curative resections. CONCLUSIONS: Yearly colonoscopy, liver CT, and chest radiography will not improve survival from colorectal cancer when added to symptom and simple screening review.

Adult↗

PubMed2000

Screening colonoscopy in asymptomatic average-risk African Americans.

BACKGROUND: Recent data indicate that colorectal cancer incidence and mortality in white Americans have been declining since 1985 at a rate of 2% to 3% per year. In African Americans, however, mortality from colorectal cancer appears to be increasing. We sought to evaluate the prevalence of colonic neoplasia in asymptomatic African Americans. METHODS: We performed a cross-sectional colonoscopy screening study to determine the prevalence of colonic neoplasia in asymptomatic African Americans older than 50 years of age. RESULTS: One hundred sixty-six subjects were evaluated for the study of whom 121 (69 women) were deemed to be asymptomatic average-risk persons and completed colonoscopy. Forty-two individuals (35%) had a total of 72 adenomas (67 tubular and 5 tubulovillous); 47 (65.3%) of these were proximal to the splenic flexure. Three subjects had an adenoma 1 cm or greater in diameter and none had severe dysplasia. CONCLUSIONS: The overall prevalence of adenomas in asymptomatic average-risk African Americans was comparable to that of previously described populations. The predominance of right-sided adenomas in this study confirms previous findings and is an area requiring further study. Until this issue is resolved, we suggest the use of colonoscopy rather than sigmoidoscopy for screening for colorectal neoplasia in asymptomatic, average-risk African Americans.

Adenomatous Polyps↗

PubMed2000

Adenoma size and number are predictive of adenoma recurrence: implications for surveillance colonoscopy.

BACKGROUND: Three-year colonoscopic surveillance after initial polypectomy may not be required for all patients. Those with multiple baseline polyps and large adenomas, implicated as predictors of colon cancer, merit close observation. Conversely, patients with single small adenomas may be subjected to early endoscopic surveillance unnecessarily. METHODS: From our Adenoma Registry we evaluated patient and adenoma characteristics in 697 patients. All had an adenoma recurrence within 3 years of a positive baseline colonoscopy. Potential risk factors studied were age, gender, number of adenomas, size of largest adenoma and histology. We defined a significant outcome as size of 1 cm or greater, tubulovillous or villous histology, high-grade dysplasia, carcinoma in situ, invasive cancer, or 4 or more adenomas. RESULTS: Having 3 or more adenomas on initial colonoscopy with at least 1 measuring 1 cm or larger greatly increased the chance of a significant finding on the first surveillance colonoscopy. Conversely, patients with 1 or 2 adenomas all measuring less than 1 cm were at extremely low risk of an important outcome within 3 years. CONCLUSIONS: Patients with 1 or 2 adenomas all measuring less than 1 cm are an identified low risk group and their first surveillance examination may be delayed beyond the standard 3 years.

Adenomatous Polyps↗

PubMed2004

A novel shape-locking guide for prevention of sigmoid looping during colonoscopy.

BACKGROUND: Looping of the endoscope in the sigmoid colon and other colonic segments often represents a significant challenge to the performance of comfortable, complete, and swift colonoscopy. This report describes the design and operation of a new device that addresses this problem, together with preliminary preclinical experience with this use of this shape-locking guide (SG-1). METHODS: The shape-locking guide is an overtube that can be converted from a flexible to a rigid configuration on demand. When in the rigid configuration, the shape-locking guide is designed to protect the colon wall from lateral forces exerted by the colonoscope. The shape-locking guide was evaluated in vitro by using an artificial colon model to learn how to operate it, and to assess feasibility for prevention of colon looping. In addition, safety was assessed in vivo in a pig model. RESULTS: In vitro, the shape-locking guide prevented colonic looping and, thereby, aided completion of "colonoscopy" in the artificial colon model. Subsequent in vivo studies demonstrated that use of the shape-locking guide is safe and feasible; it performed well with respect to ease of insertion and avoidance of sigmoid looping. There was no evidence of significant injury to the colon or adjacent abdominal viscera. CONCLUSIONS: This preliminary study shows that use of the shape-locking guide is safe and that it has performance characteristics that may assist the performance of colonoscopy. Human trials are being undertaken.

Animals↗

PubMed2004

Diagnostic value of distal colonic polyps for prediction of advanced proximal neoplasia in an average-risk population undergoing screening colonoscopy.

BACKGROUND: For colorectal cancer screening, the predictive value of distal findings in the ascertainment of proximal lesions is not fully established. The aims of this study were to assess distal findings as predictors of advanced proximal neoplasia and to compare the predictive value of endoscopy alone vs. combined endoscopic and histopathologic data. METHODS: Primary colonoscopy screening was performed in 2210 consecutive, average-risk adults. Age, gender, endoscopic (size, number of polyps), and histopathologic distal findings were used as potential predictors of advanced proximal neoplasms (i.e., any adenoma > or =1 cm in size, and/or with villous histology, and/or with severe dysplasia or invasive cancer). Polyps were defined as distal if located in the descending colon, the sigmoid colon, or the rectum. Those in other locations were designated proximal. RESULTS: Neoplastic lesions, including 11 invasive cancers, were found in 617 (27.9%) patients. Advanced proximal neoplasms without any distal adenoma were present in 1.3% of patients. Of the advanced proximal lesions, 39% were not associated with any distal polyp. Older age, male gender, and distal adenoma were independent predictors of advanced proximal neoplasms. The predictive ability of a model with endoscopic data alone did not improve after inclusion of histopathologic data. In multivariate logistic regression analysis, the predictive ability of models that use age, gender, and any combination of distal findings was relatively low. The proportion of advanced proximal neoplasms identified if any distal polyp was an indication for colonoscopy was only 62%. CONCLUSIONS: A strategy in which colonoscopy is performed solely in patients with distal colonic findings is not effective screening for the detection of advanced proximal neoplasms in an average-risk population.

Adenoma↗

PubMed1996

Why is colonoscopy more difficult in women?

BACKGROUND: In our experience colonoscopy in women is more difficult than in men. A retrospective review of 2194 colonoscopies performed by a single experienced endoscopist (CBW) showed that 31% of examinations in women were considered technically difficult compared with 16% in men. METHODS: To investigate a possible anatomic basis for this finding, normal barium enema series from 183 female and 162 male patients were identified. From these barium enemas, measurements of colonic length and mobility were independently taken by two physicians who were unaware of each patient's gender. RESULTS: Total colonic length was greater in women (median, 155 cm) compared to men (median, 145 cm), p = 0.005, despite women's smaller stature (p < 0.0001). Although there were no significant differences in rectum plus sigmoid, descending, or ascending plus cecum segmental lengths, women had longer transverse colons (female median length, 48 cm; male median length, 40 cm), p < 0.0001. There were no differences in mobility of the descending colon and transverse colon between the sexes, but the transverse colon reached the true pelvis more often in women (62%) than in men (26%), p < 0.001. CONCLUSIONS: Colonoscopy appears to be a technically more difficult procedure in women. The reason for this may be due in part to an inherently longer colon.

Adolescent↗