Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Colonoscopes”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 1,351 records · Page 75Linked to original sources

Laparoscopic colorectal surgery--are we being honest with our patients?

PURPOSE: A survey was undertaken to assess the impact of laparoscopy on the practice of colorectal surgery. METHODS: A total of 1,520 questionnaires were mailed to all members of the American Society of Colon and Rectal Surgeons; 635 (42 percent) surgeons responded, 50 percent, and indicated that one questionnaire represented their entire group practice. RESULTS: Two hundred seventy-eight (47 percent) respondents currently perform laparoscopic colorectal surgery; 62 percent (171) use the laparoscope for < or = 20 percent of their bowel resections. Conversely, only 6 percent (16) use the laparoscope in over 50 percent of resections. The percentage of surgeons who perform various procedures were right colectomy, 78 percent; left colectomy, 57 percent; stoma creations, 52 percent; anterior resection, 44 percent; Hartmann's closure, 42 percent; abdominoperineal resection, 27 percent; rectopexy, 18 percent; and total colectomy, 14 percent. If the preoperative diagnosis is known to be carcinoma, 196 (71 percent) surgeons attempted laparoscopic colorectal surgery, but 55 percent of surgeons (108) operated only for early lesions and 35 percent (68) only for palliation. To enable the procedure to be laparoscopically performed, 87 percent (243) of surgeons stated that they have changed their practice to include routine use of ureteral stents (23 percent), preoperative colonoscopic marking of small lesions (40 percent), or intraoperative colonoscopy. Despite increased use of endoscopy, there were 18 patients in whom the wrong segment of colon was removed. Moreover, nine patients had early local recurrence after resection of colon cancer, nine had early local recurrence after rectal cancer resection, and five had early port-site recurrence. Although 255 (40 percent) surgeons surveyed would themselves undergo laparoscopic colorectal surgery for a rectal villous adenoma, only 38 (6 percent) would have a laparoscopic anterior resection for cancer. CONCLUSIONS: Several important problems exist including early port-site recurrence and a dual surgical standard. Although many surgeons are eager to practice laparoscopic colorectal surgery on their patients with carcinoma, they are reluctant to have the new technique applied to themselves.

Colectomy↗

Colonoscopy in patients with a family history of colorectal cancer.

Since 1982 it has been the second author's policy to advise all patients who have presented with a positive family history of bowel cancer and who are over the age of 30 years to undergo colonoscopy. In the period to August 1990, 600 such patients had at least one colonoscopy. Colorectal polyps or cancer were detected in 270 patients (45 percent). The incidence was essentially the same for the 171 patients with only second-degree relatives affected (43 percent), for the 194 patients with more than one affected relative (45 percent), and for the 429 patients with an affected first-degree relative (46 percent). Only the 55 patients with more than one affected first-degree relative had a higher incidence (67 percent). The incidence in the 136 totally asymptomatic patients was 36 percent but was 48 percent in the 464 with symptoms. In 37 patients carcinoma was diagnosed. Even in the 30- to 39-year age group there was a 29 percent incidence of polyps or carcinoma. Colonoscopic screening of patients with a family history of bowel cancer compares favorably with mass screening for breast cancer. It is currently advised that all patients over 30 years of age with a family history of colorectal cancer undergo colonoscopy on presentation and, if clear, every four years thereafter unless two first-degree relatives are affected, when it should be every two years.

Adult↗

Subclinical time span of inflammatory bowel disease in patients with primary sclerosing cholangitis.

PURPOSE: This study is designed to describe colonic histology in patients with primary sclerosing cholangitis (PSC) without clinical symptoms of inflammatory bowel disease (IBD) and to do a follow-up study of these patients to find the time span from first detection of histologic signs until development of clinical symptoms of IBD. METHODS: In a cohort of 76 patients with PSC treated at Huddinge University Hospital, 11 patients did not have any clinical symptoms of IBD at the time of PSC diagnosis. Nine of these patients underwent diagnostic colonoscopy with multiple biopsies. RESULTS: In the group of nine PSC patients, without clinical signs of IBD undergoing colonoscopy, histologic signs of IBD were found in seven patients (6 ulcerative colitis and 1 Crohn's disease). Among them one had dysplasia, and another had epithelial changes probably positive for dysplasia. Two other patients had histologic signs of inflammation, however, not fully compatible with IBD. Three of 11 patients developed clinical symptoms of IBD after one, three, and seven years of follow-up since diagnostic colonoscopy. CONCLUSIONS: In patients with PSC, histologic signs of IBD, including premalignant changes, may precede development of clinical symptoms of IBD by as much as seven years. This indicates that IBD onset may have a substantial subclinical phase of IBD far longer than previously appreciated. This finding may be of clinical importance because underestimation of disease duration may delay inclusion of PSC patients with extensive colitis in colonoscopic surveillance programs. The subclinical phase may also allow the studies of early pathogenesis in vivo.

Adolescent↗

Coronary artery disease and colorectal neoplasia.

PURPOSE: This study was designed to determine whether patients with coronary artery disease are at elevated risk for colorectal neoplasia. METHODS: A case-control study was conducted among consecutive patients in three colonoscopy practices in New York City from 1986 to 1988. All study participants completed an interview questionnaire covering demographics, diet, environmental and behavioral exposures, family and personal medical history, and other variables. For the present study, 298 newly diagnosed colorectal adenoma cases and 107 incident cancer cases were compared with 507 colonoscoped controls without colorectal neoplasia or other significant findings on colonoscopy. Data on history of coronary artery disease (angina and/or heart attack) were obtained solely from the study participants' questionnaire responses. RESULTS: No association was observed between angina, heart attack, or either and colorectal adenomas in males. However, prior coronary artery disease was found to be associated with colorectal cancer in males more than 60 years of age and with colorectal adenomas in females aged 50 years or younger. CONCLUSION: Men with coronary artery disease may be at elevated risk for subsequent colorectal cancer. Young women with coronary artery disease also may be at elevated risk for colorectal neoplasia.

Adenomatous Polyps↗

Malignant potential in flat elevations.

Ninety-nine colonoscopically removed flat elevations were examined. They were divided into two groups: Group 1--flat elevations 1 to 5 mm in diameter (55 cases)--and Group 2--flat elevations 6 to 10 mm in diameter (44 cases). Group 2 had a higher percentage of adenomas (86.4 percent) than Group 1 (67.3 percent). In adenoma cases (flat adenomas), Group 2 tended to show a higher degree of dysplasia. The rates of mild and moderate dysplasia were 83.8 percent and 16.2 percent in Group 1 vs. 1.70 percent and 13.2 percent in Group 2, respectively. Group 2 contained six cases (15.8 percent) of intramucosal carcinoma (severe dysplasia), while there were no cancer cases in Group 1. Both malignancy rate and degree of dysplasia were size dependent; the larger the lesion the more severe the dysplasia. Our study also revealed that small flat elevations tend to contain higher numbers of nonneoplastic lesions than do larger lesions. Increased detection of nonneoplastic lesions seems to have contributed to an overall decline in the malignancy rate of flat elevations in recent reports.

Adenoma↗

Diagnostic laparoscopy and laparoscopic cecostomy for colonic pseudo-obstruction.

Marked cecal dilatation due to colonic psuedo-obstruction (Ogilvie's syndrome) is most often treated by colonoscopic decompression. When this fails, cecostomy is usually indicated if the bowel is not infarcted. We describe a new technique of laparoscopy-guided percutaneous cecostomy using T-fasteners to retract and anchor the cecum to the anterior abdominal wall and using a Foley catheter as a cecostomy tube. We performed this procedure successfully in a patient with colonic pseudo-obstruction who had marked cecal dilatation that could not be decompressed by colonoscopy. Laparoscopic inspection showed that the cecum was viable, and a laparoscopic cecostomy was placed. This procedure can be performed easily and safely and with much less morbidity than laparotomy and open cecostomy.

Aged↗

Increased risk of early colorectal neoplasms after hepatic transplant in patients with inflammatory bowel disease.

UNLABELLED: Inflammatory bowel disease (IBD) is associated with an increase in colon and rectal carcinoma. Immunosuppression after transplantation increases the incidence of certain types of tumors. PURPOSE: We reviewed the postoperative course of IBD patients who had undergone hepatic transplantation for primary sclerosing cholangitis to see whether there was an increase in the rate of colorectal neoplasms. METHODS: The charts of 44 patients from two institutions who had undergone a hepatic transplant for primary sclerosing cholangitis were reviewed. Of these 44 patients, 33 had IBD (32 chronic ulcerative colitis, 1 Crohn's). Of these 33 patients, 2 had previously undergone total colectomy/proctectomy and 4 died in the perioperative period. The remaining 27 patients had all undergone colonoscopic evaluation just prior to transplant. Postoperatively all patients were given prednisone, cyclosporine, and azathioprine. Minimum follow-up was 12 months; mean follow-up was 39 months. RESULTS: Three of the 27 patients (11.1 percent) developed early colorectal neoplasms (2 cancers, 1 large villous adenoma with severe dysplasia) at 9, 12, and 13 months post-transplant. All three patients were successfully treated with a total colectomy/proctectomy or resection of any remaining colon. These 3 patients had a mean 19-year history of IBD (range, 9-27 years), while the 24 patients without tumors had a mean 18-year history of IBD (range, 6-39 years). CONCLUSION: There is a subset of transplant patients with primary sclerosing cholangitis and IBD who rapidly develop colorectal neoplasms. Frequent surveillance is recommended for IBD patients in the post-transplant period.

Adult↗

Proliferative activity at colonic anastomoses as determined by statin. A nonproliferation-specific nuclear protein.

PURPOSE: One theory of anastomotic recurrence in large bowel carcinoma is that epithelial hyperplasia at the suture line causes metachronous carcinoma. METHODS: S44, a monoclonal antibody directed against statin, a nuclear protein expressed in quiescent cells, was used to determine whether the anastomosis represents an area with a high proliferation rate. During follow-up colonoscopic examination of patients who had undergone previous resection for colorectal carcinoma, biopsies were taken from the anastomotic site and from the mucosa 10 to 15 cm from the anastomosis. One side of 10 well-oriented crypts was counted for each patient with the number of nuclei positive for statin being determined by the presence of dark brown reaction product. RESULTS: The average percentages of statin-positive cells varied between 19.4 and 44.4 (average, 31.3 +/- 6.5) for the normal mucosa and 22.8 to 35.1 (average, 29.98 +/- 3.67) for the anastomotic mucosa. The differences were not significant. There were no differences between those patients in whom the postoperative time elapsed was two years or less and those greater than two years. CONCLUSION: This study is unique in that the proliferative activity at the site of colonic anastomosis was determined in a clinical setting, and patients in which the anastomoses were created anywhere from 1 to 14 years earlier were included. Using S44 as a marker, this study does not support the theory that suture line recurrence is a result of an enhanced proliferation rate.

Adult↗

Colorectal neoplasia in patients with ulcerative colitis and primary sclerosing cholangitis.

PURPOSE: Most patients with primary sclerosing cholangitis also have ulcerative colitis. It has been suggested that in the presence of primary sclerosing cholangitis the risk of colorectal dysplasia and carcinoma is greater than in patients with ulcerative colitis alone. METHODS: In a retrospective study, we evaluated the possibility of colorectal cancer or dysplasia in 35 consecutive patients with primary sclerosing cholangitis and ulcerative colitis seen at The Johns Hopkins Hospital between 1979 and 1991. RESULTS: Thirteen of the 35 patients (37 percent) with ulcerative colitis and primary sclerosing cholangitis had colorectal neoplasia (5 with adenocarcinoma and 8 with dysplasia). In the 27 patients undergoing colonoscopic biopsy surveillance, the cumulative incidence at 28 years of colorectal cancer was 18.5 percent and for colorectal dysplasia it was 29.6 percent. The high incidence of colorectal cancer was less than the rate of colorectal cancer in patients with extensive colitis of childhood onset without primary sclerosing cholangitis (35 percent), but the rate of colorectal cancer and dysplasia (48.1 percent) is similar to the highest rates of cancer noted in the comparison group. Because patients had subtle, quiescent colitis, a short time from diagnosis of ulcerative colitis to diagnosis of colorectal neoplasia was noted (mean, 12.2 +/- 9 years; less than 8 years in 5/13 (38.5 percent) patients). CONCLUSION: Ulcerative colitis patients with primary sclerosing cholangitis appear to have a high frequency of colorectal cancer but a rate lower than expected in patients with extensive quiescent ulcerative colitis of childhood onset alone. However, exact conclusions are complicated by the high incidence of colorectal dysplasia found, which portends malignant transformation. Because of the subtle nature of colitis, the diagnosis of ulcerative colitis is often delayed, and surveillance programs should start as soon as ulcerative colitis is diagnosed.

Adenocarcinoma↗

Diffuse microscopic angiodysplasia--a previously unreported variant of angiodysplasia. Report of a case.

PURPOSE: The entity of diffuse microscopic angiodysplasia is described, and a patient with severe gastrointestinal hemorrhage because of this submucosal source of bleeding is reported. METHOD: Case records of a patient with severe gastrointestinal hemorrhage were reviewed, and histologic findings were compared with colonoscopic and operative findings. The patient received 51 units of packed red blood cells over 3.5 months and remained undiagnosed, despite an exhaustive evaluation, until autopsy. RESULTS: Ectatic veins, venules, and capillaries were present within the submucosa in virtually every section of the small and large intestine examined (79 of 86 sections). Histologic evidence of bleeding from these submucosal vessels was identified in three sites (colon, jejunum, and ileum). The absence of endoscopically visible lesions was explained by findings that vessels did not traverse the muscularis mucosa and that mucosal depth was normal. This case of diffuse microscopic angiodysplasia, therefore, represents a unique variant, because the vascular findings were so diffuse and the mucosa remained histologically and endoscopically uninvolved, despite severe bleeding. CONCLUSION: Gastrointestinal bleeding from angiodysplasia is generally assumed to arise from endoscopically recognizable vascular ectasia within the mucosa. Thus, this case helps provide an explanation for some cases in which occult or massive bleeding is assumed to be secondary to angiodysplasia, even when endoscopic verification is not possible. Recognition of this disease process may require segmental resection or deep biopsy of endoscopically normal intestine.

Aged↗

Endoscopic diagnosis of small flat carcinoma of the colon. Report of three cases.

Most small carcinomas arise from polyps. Small lesions with cellular features of malignancy and early invasion, but with no histologic evidence of residual adenoma, are rare. Diagnosed by endoscopy, three such lesions are described. They were recognized as mucosal plaques, measuring between 6 and 8 mm in diameter. In each case, there was either synchronous or metachronous carcinoma elsewhere in the colon, as well as benign adenomatous polyps. Colonoscopic identification of such lesions allows inclusion of that bowel segment in any planned resection.

Adenocarcinoma↗

Preoperative diagnosis of a small, depressed rectal cancer complicating ulcerative colitis. Report of a case.

PURPOSE: This study was designed to clarify the importance of detecting small, depressed colorectal cancer complicating ulcerative colitis. METHODS: A 39-year-old Japanese male, who had an 18-year history of left-sided ulcerative colitis, was admitted to Fukuoka University Hospital for further evaluation of his colitis. Colonoscopy with a dye spraying method clearly revealed a small, depressed lesion and flat plaque-like lesions in the rectum. Biopsies taken from a depressed lesion and plaque-like lesions revealed a signet-ring cell carcinoma and dysplasia, respectively. Total colectomy was performed. RESULTS: Sections from the depressed rectal lesion, measuring 7 x 8 mm in size, revealed a signet-ring cell carcinoma that diffusely invaded the muscularis propria. Lymph node metastasis was evident. Flat plaques and mucosa around the depressed lesion were positive for dysplasia. CONCLUSION: This is the first report of a case of small, depressed rectal cancer complicating ulcerative colitis diagnosed by preoperative colonoscopy. To improve outcome of colonoscopic surveillance in ulcerative colitis, detecting such small, depressed lesions are important, and colonoscopy with a dye spraying method would be useful in detecting them.

Adult↗

Synchronous anorectal malignant melanoma and rectal adenocarcinoma: report of a case.

BACKGROUND: Synchronous neoplasms of the rectum are an uncommon condition. The situation becomes more rare when tumors are of different origin. To the authors' knowledge, synchronous anorectal melanoma and adenocarcinoma of the rectum have not been reported in the literature before. METHODS AND RESULTS: A 67-year-old female patient with synchronous anorectal malignant melanoma and adenocarcinoma of the rectum is described. She had preoperative colonoscopic diagnosis. The different neoplasms' origin was histologically proven. Surgical management consisted of abdominoperineal resection of the rectum. Postoperatively, the patient received adjuvant chemotherapy of six cycles duration. At present, the patient has completed 32 months of follow-up. There is no evidence of recurrent disease or distant metastases. CONCLUSION: Review of the literature confirms the rarity of anorectal malignant melanoma. On the other hand, the rectum represents the most common site for development of colonic adenocarcinoma. We were unable to trace synchronous presentation of these two tumors. Prognosis should be defined by the most malignant neoplasm; therefore, management should be focused on treating the melanoma.

Adenocarcinoma↗

Immunohistochemical analysis of statin in colorectal adenocarcinoma, polyps, and normal mucosa.

PURPOSE: The search for an understanding of the kinetics of the malignant cell is an ongoing focus of research. The aim of the present study was to determine whether there were any differences in the expression of statin, a nonproliferation-specific nuclear protein, among different colorectal tissues and whether there is any relationship between statin presence and neoplastic aggressivity. METHODS: The study population consisted of specimens from 19 patients who underwent resection for carcinoma, one for villous adenoma, and seven for colonoscopic polypectomies. Tissue samples were taken from the center of the specimen and from mucosa 10 cm from the lesion. RESULTS: Statin immunoreactivity was evaluated by counting stained nuclei in ten randomly chosen fields, and percent of positive cells was calculated. Average percentage of statin-positive cells was 34.33 +/- 6.81 in the normal crypt, 44.42 +/- 7.28 for polyps, and 7.74 +/- 5.67 for carcinomas (significantly lower than normal mucosa and polyps; P < 0.001). CONCLUSION: Statin expression is dramatically diminished in invasive carcinoma tissue, but it did not help determine aggressivity with respect to Dukes stage.

Adenocarcinoma↗

Stent endoprosthesis for obstructing colorectal cancers.

PURPOSE: Purpose of this study was to assess stent endoprosthesis for colorectal cancer (SECC) as an adjuvant to operative preparation in patients with obstructing colorectal cancers. METHODS: A self-expanding stainless steel stent was inserted in 15 patients with obstructing colorectal cancers under colonoscopic observation and fluoroscopic control. Following successful SECC, the colon was mechanically prepared using polyethylene glycol. Definitive surgical treatment then was undertaken. RESULTS: All 12 patients in whom the stent had been successfully placed recovered intestinal transit and tolerated mechanical preparation. A satisfactory preparation was confirmed during the operation. Two perforations and one dislocation were encountered. CONCLUSION: SECC is a new method for operative preparation of patients with obstructing colorectal cancers, which may reduce morbidity and mortality associated with this difficult problem.

Aged↗

Colorectal carcinogenesis: historical review.

PURPOSE: In view of the changing concept of colorectal carcinogenesis during the last 20 years, a historical review of colorectal carcinogenesis is presented. METHODS: The changing concept of colorectal carcinogenesis was presented in four different periods: 1) carcinogenesis based on surgical materials; 2) carcinogenesis based on polypectomy materials; 3) carcinogenesis based on nonpolypoid neoplasms; 4) carcinogenesis based on molecular biology. RESULTS: In the first period, large adenomas were thought to play the most important role as precursors to colorectal carcinomas; however, in the second period, smaller and nonpedunculated adenomas were found to have a much higher malignancy potential than previously thought. The discovery of nonpolypoid neoplasms, including flat and depressed adenomas/carcinomas, shed light on the new precursor of colorectal carcinomas that were not recognized in the past. Molecular biology clarified a lack of K-ras mutation in nonpolypoid, particularly depressed, neoplasms, suggesting the presence of a novel pathway of colorectal carcinogenesis, different from that in polypoid neoplasms. CONCLUSIONS: The concept referred to as the "adenoma-carcinoma sequence" changed because colonoscopic polypectomy specimens were studied, and rather small, nonpedunculated adenomas were found to play an important role as precursors of colorectal carcinomas. The discovery of nonpolypoid neoplasms provides us with new precursors of colorectal carcinomas. The genetic alterations in nonpolypoid neoplasms seem to differ from those in polypoid neoplasms, and genetic alterations in so-called de novo carcinomas need to be clarified.

Adenomatous Polyps↗

Collagenous colitis. A treatable disease with an elusive diagnosis.

Collagenous colitis is associated with normal endoscopy examination and peculiar histopathological changes. The natural history and optimal treatment are not well defined. Our objectives were to analyze the symptomatology of collagenous colitis, determine the natural history, and response to treatment. All patients with collagenous colitis from 1978 to 1992 were studied. Demographic data, symptomatology, associated conditions, colonoscopic findings, and pathology specimens were reviewed. Clinical improvement was classified as none, partial, or complete. Nineteen patients were identified, mainly white females over age 50. Mean follow-up was 22.6 months. Symptom duration was 37 months (range 4 months to 15 years). Symptoms were intermittent diarrhea (19), with a predominant nocturnal component (13); abdominal pain (15); and mild weight loss and incontinence (8). Colonoscopy was normal in 12 patients. Segmental mucosal edema and loss of vasculature pattern were present in seven. Antiperistaltic agents were used in 17 patients with no improvement (15), partial resolution (1), and complete resolution (1). Eight nonresponders received sulfasalazine. Responses were none (6) or complete (2). Ten patients received steroids (10-20 mg/day). One failed to respond. Nine initially responded completely but two relapsed. Seven patients who did not respond to any type of treatment improved eventually, two partially and five completely. These patients were younger (54.3 vs 68.3 years, P = 0.04) and symptom duration was shorter (25.4 vs 44.5 months, P = 0.38) than the rest of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Aspirin effects on colonic mucosal bleeding: implications for colonic biopsy and polypectomy.

BACKGROUND: Many patients who require endoscopic treatments such as biopsy and polypectomy are given antiplatelet agents reluctantly. We have studied the effects of aspirin on colonic mucosal hemostasis. METHODS AND PATIENTS: We developed a new endoscopic device to make a standard incision (7-mm length) on the colonic mucosa to study colon bleeding time. We measured the colon bleeding time of normal colonic mucosa in 47 cases. The colon bleeding time and skin bleeding time (Simplate method) were measured before and one hour after aspirin ingestion (990 mg) in ten healthy subjects. RESULTS: The bleeding time of normal colonic mucosa was 156 +/- 71 (mean +/- standard deviation) seconds. Significant prolongation was noted in both skin bleeding time (357 +/- 192 vs. 477 +/- 183 seconds; P < 0.05) and colon bleeding time (155 +/- 47 vs. 244 +/- 169 seconds; P < 0.05) after aspirin ingestion. CONCLUSIONS: Bleeding time was measured safely under direct colonoscopic visualization. Aspirin prolonged the colon bleeding time. Therefore, endoscopists should be aware of a risk of abnormal bleeding after endoscopic biopsy and polypectomy in patients with aspirin use. Two days were necessary for colon bleeding time to become normalized in patients with aspirin use.

Aspirin↗