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At least 937 records · Page 52Linked to original sources
PubMed1999

Efficacy of magnifying endoscopy in the differential diagnosis of neoplastic and non-neoplastic polyps of the large bowel.

PURPOSE: We have introduced magnifying colonoscopy into clinical practice and analyzed its diagnostic efficacy, especially regarding the ability to distinguish neoplastic from non-neoplastic polyps. METHODS: The materials consisted of 923 polyps. After identifying the lesions during normal colonoscopy, a dye was sprayed, and then the zoom apparatus of the colonoscope was used to make a magnified observation at a maximum 100 times magnification. We classified the crypt orifices into six categories and labeled them A to F as follows: A, a medium round appearance; B, an asteroid appearance; C, an elliptic appearance; D, a small, round appearance; E, a cerebriform appearance; F, no apparent structural appearance. RESULTS: Forty-two of 923 polyps did not reveal any clear images of crypt patterns. The percentage of histologically neoplastic change in the lesions classified as A, B, C, D, E, and F were 10, 15.9, 93.7, 100, 94.8, and 87.5 percent, respectively. When we considered types A and B to represent a crypt pattern of non-neoplastic lesions, and types C, D, E, and F to represent neoplastic lesions, and when the lesions that did not show any clear images were classified as a misjudgment, the diagnostic accuracy of neoplastic lesions (sensitivity) was 92 percent and that of non-neoplastic lesions (specificity) was 73.3 percent. Overall, the diagnostic accuracy in differentiating neoplastic from non-neoplastic lesions was 88.4 percent. Twenty-three neoplastic lesions that were misjudged to be non-neoplastic were histologically adenoma with mild atypia in 22 and adenoma with moderate atypia in 1. CONCLUSION: Magnifying colonoscopy was considered to be useful in determining the indications for colonoscopic removal.

Adenomatous Polyps↗
PubMed1999

Colonoscopy aided by magnetic 3D imaging: assessing the routine use of a stiffening sigmoid overtube to speed up the procedure.

There are not enough trained colonoscopists to cope with the present recommended number of examinations required for diagnostic and surveillance purposes. If colorectal cancer screening is to be introduced, endoscopic examination of the large bowel needs to be easier to learn and significantly quicker to carry out. The 'Bladen system', first described in 1993, is a non-radiological method of visualising the path of the endoscope, using magnetic drive coils under the patient and a chain of sensors along the biopsy channel of the instrument. In 1998, results were published using a novel computer graphics system (the RMR system), in which a much more realistic image of the endoscope could be produced using the stored positional data from the Bladen system. The RMR system has been further refined to allow, for the first time ever, accurate measurement of the effect of the passage of a colonoscope along the bowel on the lengths of different segments of the large intestine. The results obtained in 232 patients undergoing colonoscopy are analysed. In 77 of the patients, a stiffening overtube is used to splint the sigmoid colon once the endoscope is at or beyond the splenic flexure. The mean time taken to pass the colonoscope across the transverse colon is significantly shorter (p < 0.001) when an overtube is used, despite it resulting in significant lengthening of the transverse colon. The routine use of a stiffening overtube can be expected to reduce the total procedure time by between 10 and 20%.

Adult↗
PubMed2005

A preliminary prospective study of the usefulness of a magnetic endoscope locating device during colonoscopy.

BACKGROUND: Although magnetic endoscope imaging of the colonoscope via the Endoscope Positioning Detecting Unit (EPDU) has been studied to some extent in Europe, its application in the United States has been limited. The purposes of this study were to determine whether the technique enabled for accurate localization of the lesion and to determine if and how the device facilitated scope insertion and completion of the colonoscopic exam. METHODS: Outpatient colonoscopies using the EPDU were performed by three experienced surgical endoscopists over a 5-month period. A specialized scope with electromagnetic coils or a regular scope with a magnetic probe insert in the instrument channel was used for the duration of the examination to identify loops and localize pathology. RESULTS: A total of 80 colonoscopies were performed with the device. In two patients, the probe insert was removed prior to completion of the procedure; thus, the total number of examinations included in the study was 78. The EPDU was used in conjunction with transillumination to estimate the location of polyps or cancers in the 33 patients (42%) in whom such lesions were found. In the four patients who subsequently underwent operation, the lesion's location as estimated by EPDU was verified. In regard to the usefulness of the device during insertion, the EPDU led to the discovery of loops and to the application of pressure that resulted in prompt completion of the examination in 28% of cases (deemed most useful). In 33% of cases, the device identified loops and led to the application of abdominal wall pressure and early position changes, thus facilitating the examination; however it did not lead to its immediate or rapid completion. In 39% of cases, the device was not required or used for insertion due to the simple nature of the examination. CONCLUSIONS: The EPDU was accurate in estimating lesion location. The device also holds promise as an aid in the completion of difficult exams (about 30% of cases in this study).

Adenocarcinoma↗
PubMed2006

A prospective study of the efficacy of routine decontamination for gastrointestinal endoscopes and the risk factors for failure.

BACKGROUND: Patient-ready endoscopes were monitored over an 80-week period to determine the efficacy of decontamination procedures in a busy endoscopy center. Decontamination failure was related to patient and procedural parameters. METHODS: Samples from patient-ready endoscopes were cultured aerobically and anaerobically and subjected to polymerase chain reaction (PCR) to detect hepatitis B virus (HBV), hepatitis C virus (HCV), and HIV. PCR to detect coliforms from 109 culture negative washes was used as a surrogate marker for biofilm in endoscopes. PCR was used to detect the presence of Helicobactor pylori in endoscopes used on infected patients. Procedural information such as biopsy retrieval, endoscope number, diagnosis, attending personnel, and decontamination system procedures was collected. RESULTS: Gastroscopes (n = 1,376) and colonoscopes (n = 987) were equally contaminated (1.8% vs 1.9%, respectively) with low numbers of organisms commonly isolated from the nasopharynx and/or feces. Only 1 wash contained viral nucleic acid (HCV). There was a significant correlation (P < .001) between the number of times a patient-ready endoscope was contaminated and its frequency of use. Colonoscopes used on patients with gastrointestinal disease were significantly more likely to remain contaminated through the decontamination process (P < .05). All other patient, staff, and decontamination system parameters remained not statistically significant. Coliform DNA was detected in 40% of culture-negative washes collected from patient-ready endoscopes, suggesting the presence of biofilm. No H pylori DNA was detected. CONCLUSION: Recommended decontamination procedures do not entirely eliminate persistence of low numbers of organisms on a few endoscopes, but this is unlikely to cause serious consequences in patients. Bacterial biofilm is difficult to remove and may explain this low-level persistence.

Adolescent↗
PubMed2006

Accuracy of high-resolution chromoendoscopy in prediction of histologic findings in diminutive lesions of the rectosigmoid.

BACKGROUND: The ability to differentiate adenomatous from nonadenomatous colonic polyps by using chromoendoscopy would obviate the need to remove hyperplastic lesions. The aim of this study was to define the accuracy of high-resolution chromoendoscopy for the determination of colonic polyp histology. METHODS: In 158 patients, 273 polyps (<5 mm) in the rectosigmoid were estimated for their histology. The endoscopists, in two steps, predicted the histopathology of each lesion on the basis of its surface characteristics by using high-resolution colonoscope without any staining and after indigo carmine dye according to the Kudo classification. RESULTS: The resected polyps included 48 adenomatous and 225 nonadenomatous polyps. When histologically confirmed hyperplastic polyps were compared with adenomatous polyps, the prediction of hyperplastic polyps based on endoscopic findings had a sensitivity of 93%, a specificity of 60%, and an overall accuracy of 81%. The corresponding sensitivity, specificity, and overall accuracy after indigo carmine dye were 94%, 64%, and 83%, respectively. CONCLUSIONS: The results suggest that the chromoendoscopy only marginally improves the determination between hyperplastic and adenomatous polyps when using high-resolution colonoscopes. The overall accuracy rate increased after dyeing, from 81% to 83%. The omission of histopathologic analysis cannot yet be achieved by chromoendoscopy.

Adenoma↗
PubMed1980

Use of pressure release valve to prevent colonic injury during colonoscopy.

Although bowel perforation during colonoscopy is often related to direct endoscopic pressure or injury in the rectosigmoid area, colonic perforation has been also reported with overinflation of air. This latter type of rupture appears related to formation of a blind loop, to an overly competent ileocecal valve that prohibits colonic decompression, or to use of particular power sources that generate unsafe pressure levels. In an effort to obviate this pneumatic type of rupture, the authors tested a pressure release valve developed by the Olympus Corporation that supplants the standard air-water valve in available Olympus colonoscopes. Use of this valve revealed a significant difference in mean and maximal intracolonic pressures generated during colonoscopy. Moreover, its use resulted in a marked decrease in tissue damage in the pneumatically inflated cadaver colon. Incorporation of such a pressure release valve into available colonoscopes should reduce the risk of pneumatic colon rupture and improve the safety of diagnostic colonoscopy.

Air Pressure↗
PubMed2005

Flat and depressed lesions of the colorectum.

Although flat and depressed-type lesions are found by regular endoscopic view, magnification and pit pattern observation are vital parts of a precise diagnosis of the lesion. The depressed-type lesions have a prominent tendency to show malignant character, and the recognition and timely treatment of this lesion is inevitable in improving the morbidity and mortality from colorectal cancer. A magnifying colonoscope has the capability of a regular colonoscope with an additional feature: magnification. With chromoscopic techniques, the surface pattern of the mucosal pits can be observed. The pit-pattern classification correlates well with actual histologic findings and provides important additional information before endoscopic treatment of the lesion.

Colonoscopes↗
PubMed2001

Determination of glutaraldehyde residues on flexible endoscopes after chemothermal treatment in an endoscope washer-disinfector.

BACKGROUND AND STUDY AIMS: Although there are several cases of glutaraldehyde-induced colitis following colonoscopy there is only one study on residues after disinfecting. Our report describes the determination of water-soluble glutaraldehyde residues after processing endoscopes with a glutaraldehyde-containing disinfectant. MATERIALS AND METHODS: A gastroscope and a colonoscope were processed in a washer-disinfector and then immersed in 201 of NaCl solution. Glutaraldehyde was determined by high performance liquid chromatography in 84 samples. Samples were taken after immersing the endoscopes for 5 h and 24 h with and without rinsing the channels. RESULTS: After 5 h and with the channels having been rinsed, the median for colonoscopes was only 0.409 mg/l. The highest level of glutaraldehyde was 0.846 mg/l. CONCLUSIONS: After endoscopes have been processed in the washer-disinfector there is no risk of a glutaraldehyde-induced colitis, proctitis or diarrhoea.

Colonoscopes↗
PubMed2002

Use of video and magnetic endoscope imaging for rating competence at colonoscopy: validation of a measurement tool.

BACKGROUND: Counting the number of procedures performed provides at best a crude measure of technical competence in colonoscopy. The aim of this study was to develop and validate a qualitative and a quantitative score for measuring technical competency in colonoscopy using videotape evaluation. METHODS: Eighteen endoscopists with varying levels of experience were prospectively videotaped during colonoscope insertion. The following were recorded simultaneously: a closed circuit television view showing instrument handling, the endoscopic luminal view, and a continuous display of the colonoscope configuration (magnetic endoscope imaging). Videotapes were reviewed blindly and in random order by 3 experts. Performance in 3 categories was evaluated: (1) manipulation of instrument controls (0-10), (2) manipulation of the insertion tube (0-6) and (3) depth of insertion (0-4). A global assessment of competence was given for each endoscopist. RESULTS: Comparing the total scores as assessed by the 3 blinded experts, for each individual endoscopist, there were significant differences. However, there was good interobserver agreement and correlation between the individual scores and global assessment ratings of competence (p < 0.0001). CONCLUSIONS: The video assessment tool described appears to measure technical competence at colonoscopy, although in its present form it lacks reliability. Refinement of the score may improve reliability and deserves further evaluation.

Clinical Competence↗
PubMed2005

Advances in colonic imaging: technical improvements in colonoscopy.

Colonoscopy has been available since the early 1970s and has become critical to the diagnosis and management of colorectal disorders. Features of the modern colonoscope and its variants are discussed, including the role of paediatric and variable stiffness colonoscopes for difficult insertion. The place of magnetic endoscope imaging systems and simulators in routine colonoscopy and training are examined. Finally, several recent innovations are used to illustrate how colonoscopy may evolve in the future, including new takes on the current instrument as well as potentially revolutionary pain-free, technically-easy, robotic devices for examination of the bowel.

Child↗
PubMed2005

Insertability and safety of a shape-locking device for colonoscopy.

BACKGROUND: Loop formation during colonoscopy insertion results in patient pain and delays in advancement of the colonoscope tip. AIM: To assess the insertability and safety of a novel shape-locking guide (ShapeLock, USGI, San Clemente, CA) that resists looping during colonoscopy. RESULTS: In 54 patients, both a disposable and a partly reusable version of the ShapeLock received high scores (mean scores >9.0 on 1-10 scale) for ease of insertion, and ability to maneuver the colonoscope through the shape locked device. No significant trauma resulted from use of the device. CONCLUSION: A novel shape-locking device for colonoscopy can be readily and safely inserted into the colon and locked. The device warrants controlled evaluation to determine in which, if any cases, it may be useful for either experienced colonoscopists and/or those with less or minimal experience.

Adult↗
PubMed2006

Retroflexion in the colon: a useful and safe technique in the evaluation and resection of sessile polyps during colonoscopy.

OBJECTIVE: Endoscopic polypectomy has become the standard management approach for colon polyps. Three factors can make endoscopic resection of colonic polyps difficult: size, configuration, and location. We describe the use of retroflexion in the colon as a useful and routine technique using a standard colonoscope for the resection of difficult sessile polyps. METHODS: Fifteen patients in whom the retroflexion technique was used for polyp removal were prospectively identified. Each polyp was visualized and resected using both a forward and retroflexed view. RESULTS: Nine women and six men were identified between the ages of 49 and 81 years. The 15 polyps were located in the cecum (3), ascending colon (3), hepatic flexure (3), splenic flexure (2), descending colon (2), and sigmoid colon (2). All the polyps were sessile and their largest diameter ranged from 20 mm to 50 mm. Retroflexion combined with forward viewing allowed for a better assessment of the size and extent of all the polyps compared with forward viewing alone. All polyps, except two, were completely resected during the first session, using both the prograde and retroflexion approaches. No complications from retroflexion of the colonoscope, including perforation or bleeding, occurred. CONCLUSION: Retroflexion complements the conventional prograde inspection of sessile polyps that are only partially visualized on prograde view alone. Retroflexion allows a complete assessment of the lesions' size and extent and aid in their complete removal.

Aged↗
PubMed2006

Sedation-free colonoscopy using an upper endoscope is tolerable and effective in patients with low body mass index: a prospective randomized study.

OBJECTIVE: Small-caliber upper endoscopes can be used safely and effectively for sedation-free colonoscopy. The objective of the study is to assess the efficacy of a small-caliber upper endoscope (9.2 mm) comparing with a standard colonoscope (12.2 mm). METHODS: In a prospective trial, patients undergoing sedation-free colonoscopy were randomly assigned to the upper endoscope (E) or the standard colonoscope (C). Outcome measures included patient self-assessed pain score (4-point scale), endoscopist-assessed pain score (4-point scale), cecal intubation rate, difficult cecal intubation rate (>900 s), number of polyps detected, and complication rates. RESULTS: A total of 244 patients were entered. Clinical characteristics were not different between the two groups. Cecal intubation was achieved in 91.0% of the patients in each group. The mean patient self-assessed pain score (SD) was significantly lower in the E group compared with the C group: 1.44 (0.81) versus 2.08 (1.10), p < 0.001. The mean endoscopist assessment of patient pain score (SD) was significantly lower in the E group compared with the C group as well: 1.27 (0.67) versus 1.58 (0.90), p= 0.003. In patients with low body mass index (BMI < 22 kg/m(2)), the cecal intubation rate was significantly higher in the E group (97.7%vs 79.4%, p= 0.026) and the difficult cecal intubation rate was significantly lower in the E group (9.3%vs 32.4%, p= 0.011). There were no significant differences in the number of polyps detected and complication rates between the two groups. CONCLUSION: A small-caliber upper endoscope is tolerable and effective for sedation-free colonoscopy, especially in patients with low BMI.

Body Mass Index↗
PubMed1989

Optical performance of electronic imaging systems for the colon.

Electronic (video) endoscopes are a significant new development in gastroenterology, offering the potential of enhanced teaching and permanent storage of pictorial data. The primary concern of gastroenterologists is the resolution and color performance of these instruments, as these parameters have important bearings on the ability to discern pathological changes in mucosa. We sought to determine the resolution and color capabilities of electronic colonoscopes and compare them with a conventional fiber colonoscope. Resolution was determined using a standard test chart at various distances and the number of picture elements (a measure of resolution) was calculated. The mean number of picture elements was Fujinon (219), Fiber (172), Pentax (169), Toshiba (142), Olympus (140), and Welch Allyn (133). In close focus examination (target distances less than 1 cm), the Fujinon and Toshiba endoscopes had significantly higher resolution than the other instruments. Color was measured quantitatively using a standard color chart and a color analyzer. Color polygons were plotted for each endoscope on a reference chromaticity diagram. All systems had an acceptable overall performance but color was undersaturated with some systems. The optical performance of electronic endoscopes has improved considerably since the inception of electronic endoscopy.

Colonoscopes↗
PubMedDate not supplied

[Study of the movements of flexible endoscopes].

Examinations of the intestinal tract by conventional clinical endoscopic methods have shown that in the course of observations colonoscopes are subjected to a greater load than esophagogastroscopes. The load is greater by a factor of 2.2 in a number of translational motions and by a factor of 4.4 in a number of rotatory motions. Control grips are subjected to 2.5 times as much load as esophagogastroscopic controls, and colonoscopic tube bending is 2.8 times greater than that of esophagogastroscope.

Colonoscopes↗
PubMed1980

Endoscopic detection of experimentally induced colonic neoplasms in guinea pigs (Cavia porcellus).

Colonoscopic examination was performed daily on 18 normal guinea pigs for 7 weeks and on 27 guinea pigs after 24-35 weeks of biweekly intrarectal instillation of the chemical carcinogen methylnitrosourea. Four normal guinea pigs died during the first 2 weeks of the study, two from colonic perforations and two from cecal bloating due to excessive air insufflation. The other 14 normal animals remained clinically healthy and had no gross abnormalities at the end of the 7-week study. Colonic tumors were detected by colonoscopy in five of seven treated guinea pigs that had grossly visible nodular tumors on the mucosal surface of surgically resected colonic tissue. In another treated guinea pig, a tumor was detected by colonoscopy which was not confirmed grossly. In an additional two treated guinea pigs, tumors were visualized by colonoscopy which could not be demonstrated in surgically resected tissue because of their inaccessible location within the pelvic canal. At necropsy, these latter two guinea pigs had nodular, mucosal growths in the pelvic portion of the colon as indicated by colonoscopy. Microscopically, an additional 13 cases of colonic neoplasms were identified in the resected colonic tissue without gross or colonoscopic evidence of intralumenal nodular growth.

Animals↗
PubMed1989

Gastrointestinal milk intolerance of infancy.

During a period of 30 months, cow's milk- or soy protein-induced colitis was diagnosed in 22 infants. All patients presented with hematochezia. Only three patients had substantial diarrhea. Colonoscopic evaluations demonstrated a characteristic mucosal appearance, manifested by aphthoid ulcerations with intervening, normal-appearing mucosa. Histologic findings included surface ulcerations and associated inflammation of the lamina propria and submucosa, marked by substantial eosinophilic infiltration. Both clinical symptoms and colonoscopic abnormalities rapidly resolved in all patients after the elimination of cow's milk and/or soy protein from the diet. These data indicate that hematochezia may be the predominant symptom of cow's milk protein and soy protein intolerance in many affected infants, and that colonoscopy is the most effective means of establishing a definitive diagnosis in this patient population.

Colitis↗
PubMed2000

Ogilvie syndrome as a postoperative complication.

HYPOTHESIS: Ogilvie syndrome is a postoperative complication. DESIGN: Case series. SETTING: University-affiliated tertiary-care hospital. PATIENTS AND METHODS: The medical records of patients diagnosed as having Ogilvie syndrome after trauma or operation between 1989 and 1998 were reviewed. Medical charts were examined for history, treatment, cecal diameter, and outcome. MAIN OUTCOME MEASURES: Data were summarized in an attempt to identify patient populations at risk for Ogilvie syndrome. RESULTS: Ogilvie syndrome was diagnosed in 36 patients, 24 of whom were men. Average age at diagnosis was 68.9 years. Abdominal radiographs were obtained at time of diagnosis (mean cecal diameter, 13.4 cm; range, 8-20 cm). Operations preceding Ogilvie syndrome were orthopedic or spinal (n= 14), cardiothoracic (n= 12), abdominal (n= 5), and vascular (n= 2). Nonoperative trauma accounted for 3 cases. Coronary artery bypass grafting was the single most frequent procedure leading to Ogilvie syndrome (n=9 [25%]). Conservative treatment was successful in 52.8% of cases (n = 19). Twenty colonoscopic decompressions were performed on 13 patients, with an overall success rate of 77% (n= 10). Of the 3 patients in whom colonoscopic decompression failed, 2 died and 1 required operation. Five of the 36 patients required surgical intervention, with a mortality rate of 60% (n= 3). CONCLUSIONS: Previous studies have shown Ogilvie syndrome to occur most commonly after obstetrical/ gynecologic, abdominal/pelvic, and orthopedic procedures. Our data confirm that patients undergoing orthopedic and spinal procedures are at higher risk, but that the surgical procedure most commonly leading to Ogilvie syndrome was coronary artery bypass grafting. Cardiothoracic surgeons, orthopedic surgeons, and neurosurgeons should be cognizant of this complication in the patient whose abdomen becomes distended postoperatively. If recognized early and treated appropriately, pseudo-obstruction will resolve in most patients. If surgical intervention is required, the subsequent mortality rate is high.

Aged↗