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 973 records · Page 54Linked to original sources
PubMed1992

Highly malignant carcinoma in chronic ulcerative colitis without preceding dysplasia or DNA aneuploidy. Report of a case.

A 41-year-old female with a history of total ulcerative colitis for 15 years is presented. After eight years, she was enrolled in a colonoscopic surveillance program with regular examinations every second year and with biopsy sampling for histologic assessment of dysplasia as well as for flow cytometric analysis. Neither dysplasia nor DNA aneupoloidy developed during the course of the follow-up, but, after seven years, the patient developed a rapidly growing malignant stricture in the lower rectum. At the time of diagnosis, a local gluteal metastasis was found. Following preoperative radiation therapy, laparotomy disclosed a rectal cancer with local growth in the pelvis. Despite an attempt to perform curative surgery, the patient deteriorated and died within four months after the diagnosis. The carcinoma was of a poorly differentiated, mucinous, signet ring cell type, and DNA analyses of both the tumor and its metastases were diploid. Retrospective analyses of mucin content in colonoscopic biopsies showed a gradual shift from sulfated mucin to sialomucin. This case underlines the fact that even rigorous follow-ups offer no absolute guarantee against incurable malignancy in surveillance programs for ulcerative colitis despite the inclusion of DNA analyses.

Adenocarcinoma, Mucinous↗
PubMed1995

Confirmation of cecal intubation during colonoscopy.

PURPOSE: Establishing intubation of the cecum can be a laborious, frustrating, and sometimes erroneous endeavor. Following confirmed colonoscopic intubation of the cecum, the presence of three anatomic landmarks (alone and in combination) were evaluated to precisely define their reliability. METHODS: Between February 1991 and January 1992, 771 of 904 consecutive colonoscopic examinations were completed to the cecum as confirmed by fluoroscopy. RESULTS: All three cecal landmarks studied (ileocecal valve, appendiceal orifice, and transillumination) were present in 64 percent of patients, and two landmarks were seen in 32 percent (96 percent of patients had multiple landmarks). The ileocecal valve was the most reliable cecal landmark (98 percent), followed by the appendiceal orifice (87 percent) and transillumination through the abdominal wall (75 percent). CONCLUSIONS: The ileocecal valve is the most reliable cecal landmark and is invariably visualized, even when all other cecal landmarks are obscure. Although other cecal landmarks are usually identifiable, they are most valuable when found in association with the ileocecal valve.

Abdominal Muscles↗
PubMed1996

Postpolypectomy colonic hemorrhage.

PURPOSE: This study was undertaken to evaluate the incidence, diagnostic methods, and treatment of hemorrhage occurring after colonoscopic polypectomy. METHODS: A retrospective chart review was conducted of 12,058 patients who underwent colonoscopy at an academic referral center between January 1989 and July 1993. Of these, 6,365 patients required polypectomies or biopsies. RESULTS: After these procedures, 13 patients (0.2 percent) developed lower gastrointestinal hemorrhage requiring hospitalization. All bleeding episodes occurred within 12 days of polypectomy or biopsy (mean = 8 days). Twelve patients (92 percent) underwent technetium-tagged red blood cell scintigraphy, which localized bleeding in four patients (31 percent). In the eight patients with normal scintigrams, hemorrhage did not recur, and no further evaluation was performed. Five patients (38 percent) underwent arteriography. Arteriogram was positive in two of four patients with positive scintigrams, and bleeding was controlled with selective vasopressin infusion. The fifth patient had arteriography without prior diagnostic studies because of massive hemorrhage; the bleeding site was identified and controlled with selective vasopressin infusion. Three patients had lower gastrointestinal endoscopy, with endoscopic identification of bleeding site in two patients, and endoscopic electrocautery controlled the bleeding in one patient. In the 13 patients with hemorrhage, cessation of bleeding occurred with intestinal rest and hydration in nine patients (69 percent), selective vasopressin infusion in three patients (23 percent), and endoscopic electrocautery in one patient (8 percent). Eight patients (62 percent) required blood transfusion with a mean of 4.8 units (excluding one patient on warfarin sodium who required 14 units of blood). No patient required surgical intervention. CONCLUSIONS: Incidence of hemorrhage after colonoscopic polypectomy or biopsy is low, and in our series, hemorrhage resolved without the need for surgical intervention. Management includes initial stabilization followed by diagnostic evaluation. Technetium-tagged red blood cell nuclear scintigraphy identifies ongoing bleeding and identifies patients in whom additional invasive procedures (arteriography lower gastrointestinal tract endoscopy) are warranted.

Colonic Polyps↗
PubMedDate not supplied

Therapeutic colonoscopy.

Therapeutic colonoscopy has replaced or lessened to a significant degree the need or extent of traditional open surgical procedures. The common uses of therapeutic colonoscopy are hemostasis, resection and ablation of benign and malignant disease, decompression and recanalization of obstructed or dilated bowel, as well as foreign body extraction. Bleeding from arteriovenous and other vascular abnormalities can be controlled with 40% to 80% success rates using endoscopically delivered, monopolar, bipolar, or laser coagulation. The palliation of bleeding recurrent or inoperable colorectal cancer is achieved in up to 90% of patients. Virtually all pedunculated adenomas and most sessile adenomas are regularly removed colonoscopically, while large and recurrent villous adenomas in high risk individuals can be successfully managed by endoscopically delivered laser ablation techniques. Emergency colonoscopic reduction of sigmoid volvulus is performed pre-operatively and decompression of the dilated colon of non-obstructive colonic ileus is now regularly achieved. Colonic strictures have been dilated with a variety of techniques ranging from divulsion with through-the-scope balloon dilators to laser recanalization. Pre-operative endoscopic laser relief of tumor obstruction is employed to avoid preliminary or decompressing colostomy. Endoscopic laser debulking and recanalization of recurrent or inoperable cancer has been achieved with up to 80% success and various foreign bodies may be extracted from the colon with a number of endoscopic techniques. The morbidity of therapeutic colonoscopy has ranged from 1% to 2% for polypectomy to 11% for laser palliation of bleeding from advanced cancer, often with obstruction.

Adenoma↗
PubMed1996

Appendiceal mucocele with concomitant colonic cancer. Report of two cases.

PURPOSE: Mucocele of the appendix is an uncommon disorder, usually found incidentally during ultrasonography or radiographic studies. We report two cases of combined appendiceal mucocele and colonic cancer. METHODS: The two cases were analyzed for the clinicopathologic characteristics such as history, presentation, laboratory data, radiologic and endoscopic studies, pathology, and p53 immunoreactivity. RESULTS: Two patients were diagnosed with an appendiceal mucocele by ultrasound of the abdomen, together with computed tomography. Colonoscopic examination subsequently revealed synchronous colonic adenocarcinoma in both patients. Ileocecal resection following endoscopic polypectomy and a right hemicolectomy was performed for each patient. An appendiceal mucocele was histologically diagnosed as a mucinous cystadenoma. Immunohistochemical detection of abnormally high level of p53 protein was observed in colonic adenocarcinomas of both patients, whereas both appendiceal cystadenomas were negative for p53. CONCLUSIONS: To be remembered is the high frequency of concomitant gastrointestinal tumors in patients with appendiceal mucocele, especially caused by mucinous neoplasms. A total colonoscopic surveillance will afford earlier diagnosis of synchronous colonic cancers in these patients.

Adenocarcinoma↗
PubMed2001

Endoscopic treatment of colorectal benign-appearing lesions 3 cm or larger: techniques and outcome.

PURPOSE: Colonoscopic polypectomy is the preferred technique to remove the majority of polyps. The authors evaluate feasibility, safety, and the effectiveness of endoscopic treatment of colorectal benign-appearing polyps equal to or larger than 3 cm. METHODS: Ninety-seven patients with 104 giant polyps underwent polypectomy within a nine-year period. The majority of these procedures were performed on an outpatient basis, all on unsedated patients. Gross appearance, size, location, histologic characteristics, synchronous lesions, modality, and adequacy of removal of giant polyps were analyzed. The follow-up was achieved in 89 percent of patients during a period ranging from 6 to 96 months (median, 38). RESULTS: Of the 104 removed polyps, 75 (72 percent) were adenomatous, 2 (2 percent) were hyperplastic, and 27 (26 percent) were malignant polyps. Six patients had more than one giant polyp. Several additional smaller polyps were found in 52 patients and a synchronous cancer in 4. Twenty-one (20 percent) giant polyps were equal to or larger than 4 cm. Forty-nine were pedunculated, 20 were short-stalked, and 35 were sessile. Sixty-one polyps were excised in one piece, and forty-three were excised using a piecemeal technique. Only four complications (3.8 percent) were recorded; all cases were treated endoscopically. Fifty-eight (75 percent) adenomas and eighteen (67 percent) malignant polyps were completely excised. Surgery was performed in 7 of 27 patients (27 percent) with malignant polyps, where there was a doubtful, infiltrated margin or poorly differentiated cancer. Postpolypectomy surveillance permitted the detection and treatment of 25 metachronous or recurrent polyps and a metachronous cancer. CONCLUSIONS: This study shows that polypectomy of giant colorectal polyps, performed by an expert endoscopist, is feasible, effective, and safe, even on an outpatient basis. The authors confirm that malignant polyps with incomplete excision, lymphovascular invasion, and poor differentiation require bowel resection. Postpolypectomy surveillance is useful for all patients who have undergone colonoscopic resection of giant adenomatous or malignant polyps.

Adenomatous Polyps↗
PubMed1999

Colorectal cancer in inflammatory bowel disease: a continuing problem.

PURPOSE: Because of the increased risk of colorectal cancer in patients with inflammatory bowel disease, surveillance colonoscopy with mucosal biopsies for dysplasia has been advocated to prevent malignancy or permit its early diagnosis. However, despite adoption of colonoscopic surveillance programs by many clinicians, we have noted a pattern of continued referrals for inflammatory bowel disease-associated malignancy. This study was undertaken in an effort to characterize this cohort of patients. METHODS: We reviewed the operative records of a large metropolitan colorectal practice from 1983 to 1995. During this period 40 large-bowel resections were performed for patients with documented inflammatory bowel disease and concomitant carcinoma. A retrospective analysis was conducted with emphasis on clinical presentation, pathologic description, and most recent follow-up. RESULTS: Mean age at the time of diagnosis of cancer was 48 years with an average inflammatory bowel disease duration of 19 years. Seven patients had documented inflammatory bowel disease for less than eight years before their cancer diagnosis. Carcinomas were identified preoperatively by colonoscopy in 92 percent of patients. One-half of these patients had the colonoscopy to investigate a recent change in inflammatory bowel disease symptoms or signs, whereas the other half underwent endoscopy as routine surveillance. For the remaining 8 percent of patients, operated on for worsening symptoms, the carcinoma was detected in the pathological specimen only. The majority of patients (68 percent) did not have a preoperative diagnosis of dysplasia. Twenty-five percent of tumors were mucinous, 20 percent were multicentric, and 70 percent were located distal to the splenic flexure. Among the seven patients who died, four had pancolitis, six had a recent worsening of symptoms, and all had cancer involving the rectum. CONCLUSION: Cancer occurs at a younger age in patients with long-standing inflammatory bowel disease. The tumors are often mucinous, multiple, and located in the left colon. Despite increasing acceptance of surveillance colonoscopy as a recommended strategy in cancer prevention, almost one-half of the patients in this study had their cancer diagnosed because increased colitis symptoms led to colonoscopic examination. Eighteen percent of patients developed cancer with less than an eight-year history of inflammatory bowel disease. These data call into question the effectiveness of dysplasia surveillance as a population-based strategy to decrease the colorectal cancer mortality in inflammatory bowel disease patients.

Adult↗
PubMed2000

Significance of a normal surveillance colonoscopy in patients with a history of adenomatous polyps.

PURPOSE: The aim of this study was to determine the appropriate surveillance for patients with a history of adenomatous polyps whose last colonoscopic examination was normal. METHODS: This was a retrospective review of a database of 7,677 colonoscopies (1990 to 1996). In patients under colonoscopic surveillance, we reviewed cases of patients who had received three colonoscopies (an index (initial) colonoscopy positive for adenomas and 2 follow-up colonoscopies (interim and final)). The risk of adenomas and cancers at final follow-up colonoscopy was compared between patients having a normal interim colonoscopy and those with a positive interim colonoscopy. The risk at final colonoscopy was also stratified by time interval and the size and number of adenomas at the initial index colonoscopy. RESULTS: Two hundred four patients undergoing surveillance for adenomas met inclusion criteria. At index colonoscopy the median polyp size was 1 cm and median frequency was three polyps. At all follow-up colonoscopies, we detected 493 adenomas and one cancer (median follow-up, 55 months). At 36 months patients with a normal interim colonoscopy (n = 91) had significantly fewer polyps than patients with a positive interim colonoscopy (n = 113; 15 vs. 40 percent; P = 0.0001). By 40 months, adenomas were detected in more than 40 percent of patients in both groups. The risk after a normal interim colonoscopy was not affected by time interval or number or size of polyps. Adenomas found subsequent to a normal interim colonoscopy were dispersed throughout the colon in 28 patients and isolated to the rectosigmoid in 6 patients. CONCLUSIONS: In patients with a history of adenomas, a normal follow-up colonoscopy is associated with a statistically but not clinically significant reduction in the risk of subsequent colonic neoplasms. These patients require follow-up surveillance colonoscopy at a four-year to five-year interval.

Adenomatous Polyposis Coli↗
PubMed1999

Determination of factors responsible for the declining incidence of colorectal cancer.

INTRODUCTION: After rising for 13 years in the United States, the incidence of colorectal cancer began to fall in 1986 and has continued to drop since then. This report contains an analysis of the pattern of declining colorectal cancer risk by colorectal subsite, race, and gender and a time trend investigation of suspected risk modifiers of colorectal cancer. METHOD: Colorectal cancer incidence data were obtained from the Surveillance, Epidemiology, and End Results Public Use Files from 1973 to 1994. The following exposure variables were assessed, focussing principally on the period 1970 to 1980: dietary fat, fiber, ethanolic beverages, vitamin A, vitamin C, iron, calcium, estrogen, aspirin, energy intake, body mass index, serum cholesterol, body iron stores, cholecystectomy, constipation, cigarette use, physical activity, and colonoscopic polypectomy. Data sources used in these analyses were principally National Health and Nutrition Examination Surveys I, II, and III. RESULTS: After 1985 colorectal cancer incidence declined predominantly in the distal colorectum almost equally in both white males and white females. Some exposures remained unchanged or trended in the wrong direction (dietary fat, calcium, ethanol, energy intake, physical activity, overweight prevalence, and cholecystectomy). Others did not apply equally to both genders (estrogen, aspirin, ethanol, calcium, and cholecystectomy). Others may become significant in the future, such as aspirin, estrogen, or calcium, because their supplementation is now prevalent, but were not in 1970 to 1975. Of all the risk factors or interventions assessed, the one most consistent with the observed pattern of change is increased use of colonoscopic polypectomy. CONCLUSION: The best method to diminish the incidence of colorectal cancer today may be to increase the use of screening colonoscopy and polypectomy.

Colorectal Neoplasms↗
PubMed1998

Colonoscopy-assisted colostomy--an alternative to laparotomy: report of two cases.

PURPOSE: The objective of this study was to evaluate the feasibility of performing fecal diversion with the help of a colonoscope without a concomitant laparotomy. METHODS: Colostomies were performed on two patients who needed fecal diversion and who would benefit from avoiding the morbidity of laparotomy. A colonoscope was used in each case to guide the surgeon in selecting the appropriate bowel segment. RESULTS: No complications related to the colostomy were noted in either patient. CONCLUSIONS: The technique of colonoscopy-assisted colostomy that we have described offers an acceptable method of creating a stoma without the need for laparotomy.

Aged↗
PubMed1998

Perforated solitary ulcer of the colon. Report of a case.

PURPOSE: A patient with a solitary colonic ulcer had sudden onset of crampy abdominal pain, anorexia, fever, and vomiting, with signs of positive peritoneal irritation. METHODS: The diagnosis was proved by histopathologic examination of right hemicolectomy material. RESULTS: An emergency laparotomy, with right hemicolectomy and ileotransversostomy, gave complete relief from symptoms. The patient was still asymptomatic at the two-year follow-up, and control colonoscopic examinations performed at 6 and 18 months after the operation were normal. CONCLUSION: Preoperative diagnosis of perforated solitary colonic ulcers localized at the right hemicolon may mimic acute appendicitis, and intraoperative findings may mimic colonic carcinoma. If the preoperative diagnosis is not certain, right hemicolectomy and ileotransversostomy, with regular colonoscopic controls, is a safe procedure in the treatment and follow-up of these patients.

Abdomen, Acute↗
PubMedDate not supplied

Cystic lymphangioma of the colon. Endoscopic and histologic features.

Cystic lymphangiomas are rare benign tumors of the gastrointestinal tract. Such a lesion was found in the colon of a man who presented with diarrhea and rectal bleeding. The colonoscopic appearances of a smooth, soft polypoid lesion on a broad base should alert the clinician to suspect such a lesion. Histologically the lesion is characterized by submucosal lymphatic spaces with a smooth muscle component in the wall. Though colonoscopic excision, injection, or rupture of the cyst have been advocated as possible modes of treatment, surgical excision is still considered to be the treatment of choice.

Colonic Neoplasms↗
PubMed1989

Use of Nd-Yag laser ablation in colorectal obstruction and palliation in high-risk patients.

Conventional treatment for colonic obstruction due to cancer or benign anastomotic strictures in high-risk patients or unresectable cases in some form of colostomy. This procedure has the negative aspects of requiring a general anesthetic and leaves the infirm patient with a stoma that they cannot easily attend to. Ablation of tumor by Nd-Yag laser has been available for several years, with passage of the laser fiber through a colonoscope. To evaluate the role of laser photocoagulation in the palliation of colorectal tumors or benign strictures, the authors summarized their initial experience, trying to define the indications, various methods of treatment, and complication rate in these patients. This technique is difficult to perform and has the added risk of intestinal perforation but does obviate anesthetic and surgical risks. Seven patients with recurrent metastatic colorectal obstruction, three patients with benign colonic strictures, and two patients with large villous tumors were treated with Nd-Yag laser passed via the colonoscope. The mean age was 71 years (range, 52 to 86 years). Five patients received sedatives only, six patients received epidural anesthetic, and one had a general anesthetic. The average total energy used was 3702 joules on noncontact fibers, and the average number of pulses was 126. Distance of the lesion from the anal margin ranged from 0.5 to 30 cm. Ten of twelve tumors were within 15 cm of the dentate line. In the most distal lesions, manual debulking with biopsy forceps facilitated the laser treatment. Symptomatic relief was achieved in all patients. One patient required a colostomy one month after treatment because of incontinence. Another patient needed a resection of a benign stricture after three laser treatments. Other than one case of microperforation, treated conservatively with antibiotics, no other complications occurred and there was no mortality. The authors believed that the Nd-Yag laser plays a specific role in the treatment of high-risk patients.

Aged↗
PubMed1983

Colorectal schistosomiasis. Endoscopic polypectomy.

The role of colonoscopic polypectomy for schistosomal polyps was studied. The results showed that, in spite of the large number of polyps, a total of 404 polyps were removed from 20 patients. The procedure is feasible with minimal complications. A marked reduction of rectal bleeding occurred in half the patients, and the remaining half had minimal symptoms. Colonoscopic polypectomy gives equal results to colonic excision for schistosomal polyps.

Adolescent↗
PubMed1985

Small "flat adenoma" of the large bowel with special reference to its clinicopathologic features.

Thirty-three small "flat adenomas," not more than 1 cm in diameter, were collected from surgically and colonoscopically removed specimens, and their colonoscopic and histologic characteristics were described. There were 14 adenomas with mild atypia, five with moderate atypia, 14 with severe atypia (or focal carcinoma limited to the mucosa). The grade of atypia seems to increase with the size of lesions, and these lesions were assumed to play an important role in the adenoma-carcinoma sequence. The importance of recognizing the presence of these small "flat adenomas" in everyday practice is stressed.

Adenoma↗
PubMed1984

Histopathologic comparison of colorectal adenomas in English and Japanese patients.

Histopathologic comparison of colorectal adenomas removed at St. Mark's Hospital, London, England, and those removed at the University of Tokyo, Japan was performed. There were 1242 lesions in the St. Mark's series and 310 in the University of Tokyo series. All adenomas were removed either by colonoscopic polypectomy or hot biopsy. The indications and methods of colonoscopic removal were similar in the two series. Age distribution of the patients showed a younger peak incidence in the University of Tokyo series compared with the St. Mark's patients. The percentage of adenomas larger than 1 cm, of tubulovillous or villous type, and with moderate or severe dysplasia were greater in the St. Mark's series than in the University of Tokyo series. Percentages of adenomas with mild, moderate, or severe dysplasia in each category of size did not differ between the two series. In view of the fact that there is a high colorectal cancer risk in England and medium cancer risk in Japan, our results give further epidemiologic support to the concept of the adenoma-carcinoma sequence.

Adenoma↗
PubMedDate not supplied

Colonoscopy in the diagnosis of unexplained rectal bleeding.

Colonoscopy, done to elucidate the cause of obscure rectal bleeding not diagnosable on the basis of previous proctoscopic and barium-enema examinations, resulted in a 17 per cent diagnostic yield in this series. Eighteen of 105 patients were found to have lesions: three had carcinomas, six had polyps, eight had colitis, and one had proctitis. When bleeding had been demonstrated by the physician, there was a higher diagnostic yield (22.5 per cent) than when bleeding was reported only by the patient (5.9 per cent). Descriptions of the bleeding by the patients were found to be somewhat unreliable. Sixteen of the 18 lesions revealed by the colonoscope were in the left colon. It is suggested that the basic work-up for undiagnosed rectal bleeding should include history, physical examination, sigmoidoscopy, and barium-enema study. When no diagnosis is found, subsequent work-up must be individualized. When bleeding has been demonstrated to originate from the colon, colonoscopic examination should be performed.

Adolescent↗
PubMedDate not supplied

Progressive systemic sclerosis: report of a case with colonic involvement.

A case of progressive systemic sclerosis associated with colonic involvement is described. Barium-enema examination revealed segmental involvement. Colonoscopic examination of the whole range of the involved colon revealed wide-mouthed diverticula with interspersed rigid areas and numerous ulcerations. These colonoscopic findings appeared to be distinct from those associated with tuberculosis and Crohn's disease.

Adult↗