Morning Of Colonoscopy Research Articles

Optimal Timing of Simethicone Supplement for Bowel Preparation: A Prospective Randomized Controlled Trial.

Background and Aims Simethicone (SIM), as an antifoaming agent, has been shown to improve bowel preparation during colonoscopy. However, the optimal timing of SIM addition remained undetermined. We aimed to investigate the optimal timing of SIM addition to polyethylene glycol (PEG) to improve bowel preparation. Methods Eligible patients were randomly assigned to two groups: the SIM evening group (SIM addition to PEG in the evening of the day prior to colonoscopy) and the SIM morning group (SIM addition to PEG in the morning of colonoscopy). The primary outcome was Bubble Scale (BS). The secondary outcomes were Boston Bowel Preparation Scale (BBPS) and adenoma detection rate (ADR). Results A total of 419 patients were enrolled in this study. The baseline characteristics of the patients were similar in both groups. No significant differences were observed in terms of BS (8.76 ± 0.90 vs. 8.65 ± 1.16, P = 0.81), ADR (34.1% vs. 30.8%, P = 0.47), Boston Bowel Preparation Scale (BBPS) (8.59 ± 0.94 vs. 8.45 ± 1.00, P = 0.15), and withdrawal time (8.22 ± 2.04 vs. 8.01 ± 2.51, P = 0.094) between the two groups. Moreover, safety and compliance were similar in both groups. However, the SIM evening group was associated with shorter cecal intubation time (3.80 ± 1.81 vs. 4.42 ± 2.03, P < 0.001), higher BS (2.95 ± 0.26 vs. 2.88 ± 0.38, P = 0.04) in the right colon, and diminutive ADR (62.5% vs. 38.6%, P = 0.022) in the right colon, when compared to the SIM evening group. Conclusions The SIM addition to PEG in the evening of the day prior to colonoscopy can shorten cecal intubation time and improve BS scores and diminutive ADR of the right colon compared with the SIM addition to PEG in the morning of colonoscopy in bowel preparation.

528 A Patient-Centered Multidisciplinary Approach to Improve Inpatient Bowel Preparation for Colonoscopy

INTRODUCTION: The success of colonoscopy is largely dependent on the quality of bowel preparation. Inpatient colonoscopy preparations are often suboptimal, leading to missed lesions, increased complications and poor study quality. Several studies have shown improved outcomes with split-dose bowel preparation (SBDP). As such, we conducted a multidisciplinary approach to implement a universal prep protocol (UPP) for our hospitalized patients and assessed the intervention's impact on colonoscopy quality with the Boston Bowel Prep Score (BBPS). METHODS: We implemented a UPP for all our inpatient colonoscopy cases that met inclusion criteria. We initiated a patient focused multidisciplinary educational intervention to implement this UPP by administering SDBP (2L PEG at 5pm the night prior to colonoscopy and 2L at 5am the morning of colonoscopy). Educational interventions included holding multiple group meetings to educate house staff and floor nursing staff on how to order and administer the split doses. Patients and staff were educated on the benefits of split prep, how to pace bowel prep intake and dietary changes prior to colonoscopy. A universal pamphlet in English and Spanish reiterating these points was created and was provided to patients and staff for reference. Six months of prospective data, which included gender, ethnicity, indication for the procedure, and BBPS, were collected and compared to a historic pre-intervention (PI) cohort. RESULTS: A total of 155 patient records were reviewed, of these 107 eligible patients were identified. There was no statistical difference in age, ethnicity and indication between the two groups, but there was a difference in gender with 62% of PI patients being male compared to 35% males in the intervention group (IG). The gender was adjusted for in the Linear Mixed Model, which showed a statistically significant increase in BBPS in the IG (P = 0.019, OR 0.3948). CONCLUSION: Achieving adequate bowel preparation in the inpatient setting is challenging. Our study showed that a patient centered multidisciplinary approach to implement a UPP and emphasizing patient and staff education significantly improved the quality of colonoscopy, as demonstrated by the BBPS. This approach also highlights how patient engagement and patient comfort are key elements of patient focused care. Other institutions should consider this framework in improving inpatient colonoscopy quality and patient outcomes.

517 A Survey of Peri-Colonoscopy Management of Anti-Diabetic Medications

INTRODUCTION: Currently, no standardized recommendations exist for management of antidiabetic medications in diabetes mellitus type II (DMII) patients undergoing bowel cleansing for colonoscopy. This study aims to find real-world practices of gastroenterology providers in the management of anti-diabetic medications in peri-colonoscopy period for DMII patients. METHODS: An online survey was created using Google Survey and sent to thirty-three providers who are routinely involved in planning colonoscopy for patients at our tertiary medical center. Survey questions were designed to know provider practices regarding the management of anti-diabetic medications on the day before and morning of colonoscopy in DMII patients. Questions specific to six non-insulin medications and four insulins (short, intermediate, long-acting, and mixed) for each meal were framed. Two expert endocrinologists were consulted to give best practice recommendations regarding management of same anti-diabetic medications in the peri-colonoscopy period. The answers from each provider were collected and summarized. RESULTS: Among 33 providers, 24 providers (72.7%) answered the survey. Of them, 12/24 were attending physicians, 6/24 were fellow in training, 6/24 were nurse practitioners/physician assistants). Table 1–3 summarize the cumulative numbers (and percentages) for each response specific to each anti-diabetic medication and time of day. CONCLUSION: Our survey shows marked disparity amongst gastroenterology providers (attendings, fellows, and nurse practitioners/physician assistants) and with regards to endocrinologist recommendations. Lack of consensus leads to confusion at the patient level, often leading to mismanagement and sometimes even clinically significant hypoglycemic and hyperglycemic events. Gastroenterologists should team up with endocrinologists to come up with practice guidelines to standardize peri-colonoscopy management of anti-diabetic medications among DMII patients.

Analysis of the colonic mucosa associated microbiota (MAM) using brushing samples during colonic endoscopic procedures

The mucosa-associated microbiota is an important component in human microbiota. The aim was to investigate mucosa-associated microbiota using brush samples during endoscopic procedures and compare with fecal microbiota. Seven patients who were planning to undergo a routine colonoscopy were recruited. Mucosal brushing samples were taken from 3 sites (terminal ileum, ascending and sigmoid colon), and a fecal sample was taken on the morning of colonoscopy. The samples were immediately placed in microcentrifuge tubes containing DNA stabilization reagent and analyzed using the next generation sequencer. The individual differences in microbiota were more evident than the differences of the sampling sites. Actinobacteria was more abundant and Bacteroidetes was less in the brush samples than those in the fecal samples. Taxonomic composition at the genus level and the proportion of genes responsible for some functions in the brushing samples tended to be different from those in the fecal samples. Bulleidia and Oribacteriumi were significantly more abundant and the proportions of genes responsible for transcription factors and phosphotransferase system were higher in ileal mucous than those in fecal samples. Brushing during colonoscopic procedure instead of using feces samples might be useful to analyze mucosa-associated microbiota.

Risk of Postpolypectomy Bleeding With Uninterrupted Clopidogrel Therapy in an Industry-Independent, Double-Blind, Randomized Trial

Guidelines recommend withholding clopidogrel 7 days before polypectomy to decrease bleeding risk, but these were written based on limited evidence. We investigated whether uninterrupted clopidogrel therapy increases the risk of delayed postpolypectomy bleeding in patients undergoing colonoscopy. We identified patients receiving clopidogrel for cardiovascular disease undergoing elective colonoscopies in Hong Kong from February 28, 2012 through April 11, 2018. Eligible patients were instructed to stop taking clopidogrel 7 days before colonoscopy. Then, they were randomly assigned to groups given clopidogrel (75 mg) or placebo daily until the morning of colonoscopy. All patients resumed their usual prescriptions of clopidogrel after colonoscopy. The primary end point was delayed postpolypectomy bleeding that required hospitalization or intervention up to 30 days after colonoscopy. Secondary end points were immediate postpolypectomy bleeding and serious cardio-thrombotic events for as long as 6 months after colonoscopy, according to Antithrombotic Trialists' criteria. All events were adjudicated by an independent masked committee. In total, 387 patients underwent colonoscopy and 216 required polypectomies (106 patients in the clopidogrel group and 110 patients in the placebo group). The cumulative incidence of delayed postpolypectomy bleeding was 3.8% (95% confidence interval 1.4-9.7) in the clopidogrel group and 3.6% (95% confidence interval 1.4-9.4) in the placebo group (P= .945 by log-rank test). There were no significant differences in immediate postpolypectomy bleeding (8.5% vs 5.5%; P= .380) andcardio-thrombotic events (1.5% vs 2%; P= .713). In a randomized controlled trial of clopidogrel users undergoing colonoscopy, a slightly larger proportion of patients continuing clopidogrel developed delayed and immediate postpolypectomy bleeding, although this difference was not statistically significant. ClinicalTrials.gov, number NCT01806090.

Impact of the quality of bowel cleansing on the efficacy of colonic cancer screening: a prospective, randomized, blinded study.

ObjectivesEfficacy of two low volume bowel cleansing preparations, polyethylene glycol plus ascorbate (PEG+Asc) and sodium picosulfate/magnesium citrate (NaPic/MgCit), were compared for polyp and adenoma detection rate (PDR and ADR) and overall cleansing ability. Primary endpoint was PDR (the number of patients with ≥1 polypoid or flat lesion recorded by the colonoscopist).MethodsDiagnostic, surveillance or screening colonoscopy patients were enrolled into this investigator-blinded, multi-center Phase IV study and randomized 1:1 to receive PEG+Asc (administered the evening before and the morning of colonoscopy, per label) or NaPic/MgCit (administered in the morning and afternoon the day before colonoscopy, per label). The blinded colonoscopist documented any lesion and assessed cleansing quality (Harefield Cleansing Scale).ResultsOf 394 patients who completed the study, 393 (PEG+Asc, N=200; NaPic/MgCit, N=193) had a colonoscopy. Overall PDR for PEG+Asc versus NaPic/MgCit was 51.5% versus 44.0%, p=0.139. PDR and ADR on the right side of the bowel were significantly higher with PEG+Asc versus NaPic/MgCit (PDR: 56[28.0%] versus 32[16.6%], p=0.007; ADR: 42[21.0%] versus 23[11.9%], p=0.015), as was detection of flat lesions (43[21.5%] versus 25[13.0%], p=0.025). Cleansing quality was better with PEG+Asc than NaPic/MgCit (98.5% versus 57.5% considered successful cleansing). Overall, there were 132 treatment-emergent adverse events (93 versus 39 for PEG+Asc and NaPic/MgCit, respectively). These were mainly mild abdominal symptoms, all of which were reported for higher proportions of patients in the PEG+Asc than NaPic/MgCit group. Twice as many patients in the NaPic/MgCit versus the PEG+Asc group reported tolerance of cleansing solution as ‘very good’.ConclusionsCompared with NaPic/MgCit, PEG+Asc may be more efficacious for overall cleansing ability, and subsequent detection of right-sided and flat lesions. This is likely attributable to the different administration schedules of the two bowel cleansing preparations, which may positively impact the detection and prevention of colorectal cancer, thereby improving mortality rates.Trial RegistrationClinicalTrials.gov NCT01689792.

Morning-only Polyethylene Glycol Is Noninferior but Less Preferred by Hospitalized Patients as Compared With Split-dose Bowel Preparation

To compare the efficacy and tolerability of morning-only polyethylene glycol (PEG) with split-dose preparation in hospitalized patients scheduled for colonoscopy. Morning-only colonoscopy preparation may improve efficiency by allowing patient preparation and colonoscopy to be performed on the same day. There are limited data comparing morning-only with split-dose preparation, and more studies are needed before morning-only preparation can be routinely recommended. A single-center, prospective, endoscopist-blinded study was conducted, in which hospitalized patients scheduled to undergo diagnostic colonoscopy were randomly assigned to receive 4 L of PEG either on the morning of colonoscopy or as a split-dose (evening-morning). The primary endpoint was efficacy of bowel preparation measured by the Ottawa scale. Secondary endpoints were patient compliance and tolerance. A total of 120 hospitalized patients scheduled for diagnostic colonoscopy were randomized. The mean total Ottawa score was slightly superior for the morning-only arm, and the upper bound of 95% confidence interval (CI) for difference between arms was less than our prespecified noninferiority margin of 1.5 (difference=-0.23; 95% CI, -1.72 to 1.25). The percentage of patients with good bowel preparation was similar for all colonic segments. There was a trend toward more side effects among patients in the morning-only compared with the split-dose arm (71% vs. 54%; P=0.08). Compared with morning-only preparation, more patients in the split-dose arm were willing to undergo similar preparation for future colonoscopies (71% vs. 89%; P=0.02). Morning-only PEG is not inferior to split-dose preparation regarding bowel cleansing efficacy for colonoscopy in hospitalized patients. However, split-dose preparation was preferred by patients because of less side effects.

Su1549 Colonic Preparation Before Colonoscopy: Evaluation of a New Method With Intracolonic Infusion of Water Compared to Classical Administration of PEG

Bowel cleansing before colonoscopy is currently based upon lavage solutions of polyethylene glycol (PEG) or NaP with large amounts of fluids ingested in a splitted manner. This prospective randomized study compared a PEG protocol with a new method of bowel cleansing based upon infusion of water into the colon at low pressure (PrepSystem, novoGI, Netanya, Israel). Patients and Method: The device for water infusion (novoGI, Lifestream, Austin, TX) is made of a reservoir of water maintained at 37°C. The patient is installed on an adapted seat allowing easy evacuation of water and faeces. Water is infused by gravity through a cannula, into the rectum. Patients with an indication of colonoscopy and no history of colorectal surgery or IBD were randomly assigned to PEG preparation (2L PEG in the evening before and 2L in the morning of colonoscopy) or the Prepsystem. All patients followed a low residue diet for 5 days. In the Prepsystem group, sennosides (Pursennide 80mg, Novartis, Rueil Malmaison, France) were administered in the evening before and patients underwent 2 cleansing cycles, by infusion of 35L tap water each, about one hour before the colonoscopy. Quality of bowel cleansing was assessed with the Boston score by an endoscopist blinded to the preparation type. Boston scores in both groups were compared with a non-parametric test, with a signifcance level of 5%.

193 Optimal Bowel Cleansing for Colonoscopy: Split the Dose! a Series of Meta-Analyses of Controlled Studies

Colonoscopy quality begins with a clean colon. Inadequate bowel cleansing can result in missed lesions, aborted procedures, increased patient's discomfort, procedural time and, potentially, complications. As for patients' tolerability, one of the most suitable regimen is to split the dose of laxative between the day before and the morning of colonoscopy. Nevertheless, even if different schemes and cleansing methods are available, there is no clearcut superiority of any over the otherTo evaluate the differences in colon cleansing comparing the split vs.

Morning-Only One-Gallon Polyethylene Glycol Improves Bowel Cleansing for Afternoon Colonoscopies: A Randomized Endoscopist-Blinded Prospective Study

Inadequate bowel preparation is a known factor associated with increased failure rates of afternoon colonoscopy and lower adenoma detection rates. The aim of our study was to compare the efficacy of bowel cleansing achieved by administering 1-gallon (4 l) polyethylene glycol (PEG) preparation to patients in the morning of an afternoon colonoscopy with that of the traditional evening regimen. A prospective endoscopist-blinded study was conducted, in which patients undergoing afternoon colonoscopy were randomized to receive either 1 gallon of PEG the evening before the procedure or the morning of the colonoscopy. Bowel cleansing efficacy was scored by a blinded endoscopist using the Ottawa scale and each participant filled out a satisfaction survey. Mean scores for each bowel segment, composite mean scores, and rates of "good prep" interpreted from the Ottawa scale were compared between the two groups. A total of 136 patients (mean age 51.8 years, 52.2% men) evenly distributed between the two groups formed the study sample. Patients in the morning group had significantly lower Ottawa scale scores and were more likely to have a good preparation for each bowel segment and overall when compared with the evening group (P<0.01). Moreover, patients in the morning group were over 50% less likely to lose sleep or have bloating compared with the evening group (P<0.05). There was no difference in the study groups on overall polyp detection rate, adenomatous polyps, or number of patients with adenomas. This study shows that the bowel cleansing efficacy of morning-only 1-gallon PEG is superior and better tolerated compared with consumption of 1-gallon PEG in the evening before the day of an afternoon colonoscopy. Thus, administering 1-gallon PEG solution in the morning of an afternoon colonoscopy is a feasible option that can improve the quality of an afternoon colonoscopy.

A randomized clinical study comparing reduced-volume oral sulfate solution with standard 4-liter sulfate-free electrolyte lavage solution as preparation for colonoscopy

Low-volume bowel preparations for colonoscopy improve tolerability. We compared the efficacy, tolerability, and safety of a new low-volume sulfate solution with a standard 4-L polyethylene glycol electrolyte lavage solution as bowel preparation for colonoscopy. Multicenter, single-blind, randomized, noninferiority study. Five academic and community endoscopy centers in the United States. One hundred thirty-six outpatients undergoing colonoscopy. Patients were randomized to receive 4 L sulfate-free electrolyte lavage solution (SF-ELS) given the night before colonoscopy versus 12 oz oral sulfate solution (OSS) given in equally divided doses the evening before and the morning of colonoscopy. Successful (ie, good or excellent) bowel preparation. Successful bowel preparation was more frequent with OSS than with SF-ELS (98.4% vs 89.6%; P = .04). Excellent preparation also was achieved more frequently with OSS (71.4% vs 34.3%; P < .001). Patients receiving OSS had less residual stool in the cecum and ascending colon and less residual fluid in the cecum and ascending, transverse, and descending colon compared with SF-ELS. The percentage of patients with GI side effects and adverse events was not significantly different between the 2 groups. The OSS was administered in split doses, whereas the SF-ELS was administered the evening before (which is its FDA-approved regimen). Oral sulfate solution is promising as a safe low-volume preparation for colonoscopy. ( NCT00856843.).

Multi-center, Endoscopist-blinded, Randomized Prospective Trial to Evaluate L-glucose as Bowel Preparation before Colonoscopy

Purpose: To use a positive control design to evaluate the safety, tolerability, and efficacy of split-dosed L-glucose, a non-nutritive enantiomer of D-glucose (Raymer, et al. 2003), as a bowel cleanser before colonoscopy. Methods: Males and nonpregnant females over 18 years who were scheduled to undergo outpatient colonoscopy at one of 3 study sites were eligible. Exclusion criteria included CHF and recent myocardial infarction. Subjects were gender balanced at each site and randomized in a 2:1 ratio to one of two split-dosed prep groups: L-glucose 52.8 g X 52.8 g or polyethylene glycol with ascorbic acid (PEG-AA, MoviPrep®) 1 L X 1 L, which served as a positive control. L-glucose subjects had a light breakfast then clear liquids for the rest of the day. L-glucose was given as two 8-oz (236 mL) doses at 6 pm the evening before colonoscopy and 4 hours before the exam. PEG-AA subjects were permitted a breakfast and light lunch per manufacturer's instructions. PEG-AA was given as two 1-L doses on the evening before and morning of colonoscopy. Bowel cleansing was rated using a global and a segmental scoring system. Laboratory parameters were tested at screening, after the second dose, and on the day following exam. Subjects completed a tolerability questionnaire. Results: 144 subjects (95 L-glucose, 49 PEG-AA) completed the protocol. Study groups were similar in age and ethnicity. Bowel preparation effectiveness is shown in the table below. Mean number of bowel movements in L-glucose subjects was 15.4 ± 6.8 (range 3-41). Side effects reported by L-glucose subjects included bloating (43.2%), anal irritation (37.9%), nausea (34.7%), weakness/faint feeling (18.9%), and vomiting (8.4%); most were rated mild in severity. Compared to males, females in the L-glucose group experienced higher incidences of all queried side effects and significantly higher incidences of nausea (F = 47.9%, M = 21.3%; p = 0.008) and weakness/faint feeling (F = 31.3%, M = 6.4%; p = 0.005). Small but measurable changes in serum electrolytes, liver function tests, and hematology from screening to exam were noted in L-glucose subjects, though none were clinically significant. There were no treatment-emergent serious adverse events. Willingness to repeat the bowel prep for a future exam was reported by 88.4% of L-glucose subjects. Conclusion: L-glucose provided excellent bowel cleansing for colonoscopy with acceptable tolerability in this proof-of-concept study. Females in the L-glucose group reported side effects more frequently than males, a finding that warrants further study. Additional blinded head-to-head studies of L-glucose and available bowel cleansers are needed to further evaluate the effectiveness and safety of this agent in preparation for colonoscopy. Disclosure: Dr Balaban - Consultant: Fleet Laboratories Dr Malek - Speaker's Bureau: Fleet Laboratories Dr Thompson - Consultant: Fleet Laboratories Sherrie McNamara - Employee: Fleet Laboratories. This research was supported by an industry grant from Fleet Laboratories.Table: Effectiveness of bowel cleansing

Colonoscopy Bowel Preparation in Patients with Long QT Syndrome

Introduction: Patients with long QT syndrome are at risk for sudden death from arrhythmias. Colonoscopy bowel preparation is known to occasionally cause changes in serum electrolytes, magnesium and calcium. Hypokalemia and hypomagnesaemia can prolong QT interval and can lead to life threatening arrhythmias and sudden cardiac death in patients with long QT syndrome. Case: A 44-year-old female with family history of colon cancer requested colonoscopic screening. She had a history of congenital long QT syndrome and had refused implantable cardiac defibrillator. Her baseline serum electrolytes and magnesium levels were normal. Baseline EKG showed a QTc interval of 488 msec. The patient was given sodium phosphate bowel preparation, 45 ml the evening before and 45 ml on the morning of colonoscopy. After colonoscopy preparation her potassium was 3.2 mmol/L and magnesium was 1.6 mg/dl. EKG showed that her QTc interval had increased to 500 msec. She was asymptomatic and cardiac monitoring did not reveal any arrhythmias. She was repleted with intravenous and oral potassium and magnesium. Colonoscopy was performed without any adverse effects. Discussion: Although this patient suffered no adverse consequences this case highlights the importance of avoiding hypokalemia and hypomagnesaemia during colonoscopy bowel preparation in patients with long QT syndrome. Options to consider in such patients would be to supplement potassium and magnesium during bowel preparation or to use a magnesium containing bowel preparation.*

SODIUM PHOSPHATE (NaP) COLONOSCOPY PREPARATION

Purpose: NaP solution is easier to tolerate, yet equally efficacious as large volume oral lavage solutions. However, a considerable number of patients taking NaP still have poor cleansing. The purpose of our study was to assess the effect of adding bisacodyl on cleansing and patient tolerance. Methods: In this prospective randomized double-blind placebo-controlled trial, 175 patients took NaP solution, plus four tablets of placebo (F), while 172 patients took F plus four 5 mg tablets (total of 20mg) of bisacodyl (F+B). NaP was taken at 7:00 p.m. the day before and 6:00 a.m. the morning of colonoscopy. Bisacodyl orplacebo was taken at 7:00 p.m. the evening before colonoscopy. Results: F+B resulted in significantly improved cleansing (p <0.001). Excellent or good cleansing of right colon occurred in 92% vs 76% in F+B vs F respectively (p <0.001). F+B resulted in improved cleansing for patients with bowel frequencies of once every one, two, or three days (p <0.005), but had no additive benefit for patients with bowel frequency more than once a day (p = NS). However, F+B negatively affected patient tolerance. There was more nausea (p <0.001), abdominal cramps (p <0.005), anal soreness (p <0.02) and nocturnal diarrhea (p <0.001) in F+B. Conclusions: F+B significantly improves cleansing than F. Minor adverse effects, in terms of patient tolerance, occur more often with F+B.

The effectiveness of simethicone in improving visibility during colonoscopy when given with a sodium phosphate solution: A double-blind randomized study

Background: Oral sodium phosphate solution is better tolerated than polyethylene glycol when used for colonoscopy preparation, but visibility of the lumen can be impaired because of the presence of bubbles. Methods: We studied 86 patients receiving either simethicone (n = 42) or placebo (n = 44) in addition to oral sodium phosphate to determine if simethicone improved visibility during colonoscopy. Patients were randomized to receive 160 mg of simethicone or a placebo with 45 ml of sodium phosphate the evening before and the morning of colonoscopy. Colonoscopy was performed by a single blinded investigator. Five areas of the colon (rectosigmoid, descending, transverse, ascending, and cecum) were assessed for the presence of bubbles on withdrawal of the endoscope. Bubbles were scored as follows: 0, minimal or none; 1, covering half the lumen; 2, covering the entire circumference; 3, filling the entire lumen. Results: Thirteen patients in the placebo group and only one in the simethicone had significant bubbles (≥ 1). Additionally, the mean bubble scores were greater in the placebo group in each region of the colon ( p ≤ 0.05 in rectosigmoid and ascending colon). Conclusions: This study indicates that taking simethicone with an oral sodium phosphate preparation can improve colonic visibility by diminishing the presence of bubbles. Better visualization could improve detection of mucosal pathologic lesions. (Gastrointest Endosc 1995;42:413-5.)