Peter J. Basford

High-definition endoscopy with i-Scan for evaluation of small colon polyps:: the HiSCOPE study

BACKGROUND Traditional white-light endoscopy cannot reliably distinguish between small (<10 mm) adenomatous and hyperplastic colon polyps. High-definition white-light (HDWL) endoscopy and i-Scan may improve in vivo characterization of small colon polyps. OBJECTIVE To compare HDWL endoscopy and HDWL plus i-Scan for the assessment of small colon polyps and to measure performance against the American Society for Gastrointestinal Endoscopy (ASGE) thresholds for assessment of diminutive colon polyps. DESIGN Prospective cohort study. SETTING Single academic hospital. PATIENTS Patients undergoing bowel cancer screening colonoscopy. INTERVENTION In vivo assessment of all polyps <10 mm by using HDWL and i-Scan image enhancement. MAIN OUTCOME MEASUREMENTS The primary outcome measure was overall diagnostic accuracy of in vivo assessment of colon polyps <10 mm. Secondary outcome measures were sensitivity and specificity for adenomatous histology, negative predictive value for adenomatous histology of diminutive rectosigmoid polyps, and accuracy of prediction of polyp surveillance intervals. RESULTS A total of 209 polyps in 84 patients were included. There were no significant differences between HDWL endoscopy and i-Scan in characterization of polyps <10 mm (accuracy 93.3% vs 94.7%; P = 1.00; sensitivity 95.5% vs 97.0%; P = .50; specificity 89.3% vs 90.7%; P = 1.00). The negative predictive value for adenomatous histology of diminutive rectosigmoid polyps was 100% with both HDWL endoscopy and i-Scan. U.K. and U.S. polyp surveillance intervals were predicted with 95.2% accuracy with HDWL endoscopy and 97.2% accuracy with i-Scan. LIMITATIONS Single-center study. CONCLUSION HDWL endoscopy may be as accurate as HDWL with i-Scan image enhancement for the in vivo characterization of small colon polyps. Both modalities fulfil the ASGE performance thresholds for the assessment of diminutive colon polyps. ( CLINICAL TRIAL REGISTRATION NUMBER NCT01761279.).

Endoscopic management of nonampullary duodenal polyps

Duodenal polyps are a rare finding in patients presenting for gastroscopy, being found in 0.3–4.6% of cases. The majority of patients are asymptomatic. The most common lesions necessitating removal are duodenal adenomas which should be differentiated from other mucosal lesions such as ectopic gastric mucosa, and submucosal lesions such as carcinoids and gastrointestinal stromal tumours (GISTs). Adenomas can occur sporadically or as part of a polyposis syndrome. Both groups carry malignant potential but this is higher in patients with a polyposis syndrome. The majority of sporadic duodenal adenomas are flat or sessile and occur in the second part of the duodenum. Historically duodenal adenomas have been managed by radical surgery, which carried significant mortality and morbidity, or more conservative local surgical excision which resulted in high local recurrence rates. There is growing evidence for the use of endoscopic mucosal resection (EMR) techniques for treatment of sporadic nonampullary duodenal adenomas, with good outcomes and low complication rates. Endoscopic submucosal dissection (ESD) carries greater risk of complications and should be reserved for experts in this technique. Patients with sporadic duodenal adenomas carry an increased risk of colonic neoplasia and should be offered colonoscopy. The impact of endoscopic resection on the course of polyposis syndromes such as familial adenomatous polyposis (FAP) needs further study.

Risk stratification system for evaluation of complex polyps can predict outcomes of endoscopic mucosal resection.

BACKGROUND: Apart from size, little is known about what makes a colonic polyp difficult to endoscopically remove. OBJECTIVE: The aim of this study was to evaluate polyp complexity by using a novel classification system and to assess how this affects success at endoscopic resection. DESIGN: This prospective cohort study was conducted at a tertiary referral center in the United Kingdom. INTERVENTIONS: Data were collected on patients referred for endoscopic resection of polyps >2 cm in size. Lesions were classified on the basis of size, morphology, site, and ease of access with the use of a novel scoring system (size/morphology/site/access). Endoscopic resection was performed to resect the lesions. Patients were followed up endoscopically to assess clinical outcomes. MAIN OUTCOME MEASURES: The primary outcomes measured were the endoscopic cure and complication rate by size/morphology/site/access grade and the cost savings of endoscopic resection over surgery. RESULTS: Endoscopic resection was performed on 220 patients (135 male) with 220 polyps, mean size of 43 mm (range, 20 mm–150 mm). Thirty-seven percent were classified as size/morphology/site/access 2 or 3; 63% were classified as the most challenging size/morphology/site/access level 4. Complete endoscopic clearance was achieved in 90% of cases with the first endoscopic resection attempt, improving to 96% with further endoscopic resection attempts. There were complications in 18 of 220 (8.1%) of cases. Complications were independent of lesion size and location but were affected by size/morphology/site/access grade (p = 0.018). Probability of clearance at first endoscopic resection attempt was affected by lesion complexity. Size/morphology/site/access 2 and 3 = 97.5 vs SMSA 4 = 87.5% (p = 0.009). Probability of cancer was not affected by size/morphology/site/access grade. For the whole cohort, endoscopic resection represented a cost saving of £726,288 (

Duration of acetowhitening as a novel objective tool for diagnosing high risk neoplasia in Barrett's esophagus: a prospective cohort trial.

1,123,858.05) over that of surgery. LIMITATIONS: The main limitation of this study is that it is a single-center, single-endoscopist series. CONCLUSIONS: The size/morphology/site/access scoring system is easy to use and provides valuable information on the lesion complexity and success and complication rates of endoscopic resection. This can be used for service planning, training endoscopists, and providing prognostic information for patients.

A randomized controlled trial of pre-procedure simethicone and N-acetylcysteine to improve mucosal visibility during gastroscopy – NICEVIS

BACKGROUND AND STUDY AIMS Acetic acid reacts with Barretts mucosa to produce acetowhitening which disappears with time. The clinical significance of this is unknown. We aimed to quantify the acetowhitening time, developing an objective tool for diagnosis of neoplasia in Barretts esophagus. PATIENTS AND METHODS Prospective cohort study in a tertiary referral center, enrolling patients undergoing surveillance of Barretts metaplasia or referred with suspected neoplasia. Acetic acid 2.5 % was applied to the mucosa via a spray catheter. Acetowhitening was observed and time to disappearance recorded. Targeted biopsies of any neoplasia and quadrantic 2-cm biopsies of residual Barretts area were then taken. Histological findings were investigated in relation to duration of acetowhitening. RESULTS 132 patients were examined. A receiver operating characteristic (ROC) curve was produced for identifying high risk neoplasia according to acetowhitening duration. The area under the curve (AUC) was 0.93 (0.89 - 0.97). Using a threshold of 142 seconds yielded a sensitivity for neoplasia of 98 % (95 % confidence interval [95 %CI] 89 % - 100 %) and specificity of 84 % (74 % - 91 %). The ROC curve for mucosal neoplasia (high grade dysplasia or intramucosal carcinoma) versus deep invasive cancer showed an AUC of 0.786 (0.61 - 0.96); a cutoff of 20 seconds yielded a sensitivity and specificity for invasive cancer of 67 % (35 % - 90 %) and 85 % (69 % - 95 %), respectively. CONCLUSION The time to disappearance of acetowhitening can serve as a simple but very sensitive tool for the diagnosis of high risk neoplasia in Barretts esophagus. It can be used to distinguish mucosal neoplasia from deep invasive cancer.

ASGE Technology Committee reviews on real-time endoscopic assessment of the histology of diminutive colorectal polyps, and high-definition and high-magnification endoscopes

Background and study aims: Mucosal views can be impaired by residual bubbles and mucus during gastroscopy. This study aimed to determine whether a pre-gastroscopy drink containing simethicone and N-acetylcysteine improves mucosal visualisation. Patients and methods: We conducted a randomized controlled trial recruiting 126 subjects undergoing routine gastroscopy. Subjects were randomized 1:1:1 to receive: A—pre-procedure drink of water, simethicone and N-acetylcysteine (NAC); B—water alone; or C—no preparation. Study endoscopists were blinded to group allocation. Digital images were taken at 4 locations (lower esophagus/upper gastric body/antrum/fundus), and rated for mucosal visibility (MV) using a 4-point scale (1 = best, 4 = worst) by 4 separate experienced endoscopists. The primary outcome measure was mean mucosal visibility score (MVS). Secondary outcome measures were procedure duration and volume of fluid flush required to achieve adequate mucosal views. Results: Mean MVS for Group A was significantly better than for Group B (1.35 vs 2.11, P < 0.001) and Group C (1.35 vs 2.21, P < 0.001). Mean flush volume required to achieve adequate mucosal views was significantly lower in Group A than Group B (2.0 mL vs 31.5 mL, P = 0.001) and Group C (2.0 mL vs 39.2 mL P < 0.001). Procedure duration did not differ significantly between any of the 3 groups. MV scores at each of the 4 locations demonstrated significantly better mucosal visibility in Group A compared to Group B and Group C (P < 0.0025 for all comparisons). Conclusions: A pre-procedure drink containing simethicone and NAC significantly improves mucosal visibility during gastroscopy and reduces the need for flushes during the procedure. Effectiveness in the lower esophagus demonstrates potential benefit in Barrett’s oesophagus surveillance gastroscopy.

Tips for GP trainees working in general medicine.

with continued insufflation with CO2, tension capnopericardium developed. Another lesson learned concerns the necessity of closing the mucosotomy. In our case, the mucosotomy was not closed; yet, it was completely sealed radiographically by day 3 and clinically by day 7 based on tolerance of a soft diet. This information could be helpful if closure is not possible because of intolerance of the procedure or for technical reasons. A third take-home lesson is that this patient experienced significant symptomatic improvement after creation of the submucosal tunnel only. We and others have noticed that the gastroesophageal junction (GEJ) is significantly relaxed during esophagoscopy after the submucosal tunnel has been created but before myotomy. A recent study looked at GEJ distensibility changes during specific time points throughout the POEM procedure and found a great increase in GEJ distensibility with the creation of the submucosal tunnel alone. Although these results are encouraging, long-term follow-up will be needed to determine whether our patient obtains any durable benefit from the submucosal tunnel alone. Finally, it should be noted that CO2 was used for insufflation because it is water soluble (unlike nitrogen) and is rapidly absorbed if there is extravasation into the peritoneal cavity, mediastinum, or pleural spaces. The patient’s pulse returned with 10 minutes of CPR and ACLS protocol. Had we not used CO2, the tension pneumopericardium might have persisted much longer, and the outcome could have been far worse. With the increasing popularity of POEM procedures it is important to note that rare but life-threatening adverse events may occur. In addition to arrhythmia and other cardiac adverse events, tension capnopericardium should be considered if there is sudden loss of blood pressure and pulse during POEM. Closure of the esophageal mucosotomy may not be strictly necessary, especially if the myotomy is begun a few centimeters distal to this site, although we take no chances and continue to perform clip closure in all our cases. The role of the submucosal tunnel alone in providing symptom relief is an interesting observation, but it is unclear whether the effect is durable, or whether this observation would be applicable to all patients. Finally, because of possible pneumoperitoneum, pneumomediastinum, or pneumopericardium, insufflation with CO2 is highly recommended rather than air insufflation.

Sa1458 Nicevis - Results of a Randomised Controlled Trial of Simeticone and N-Acetylcysteine As a Pre-Procedure Drink to Improve Mucosal Visibility During Diagnostic Gastroscopy

During your GP training you will spend time as a medical SHO, a period that may daunt you. Ward rounds can be long and patients may be complex, have multiple problems, and often be seriously unwell. Remember you are part of a team and people are there to help you. The majority of the skills that you need will have already been developed during your foundation years, and the idea is to expose you to common conditions that you will encounter during your career as a GP. You will also learn leadership and management skills. As the firm SHO, it’s your job to ensure the ward round is smooth and that things get done. Lead and look after your house officers — they will probably come to you first with any problems. Try and remember what it was like when you first arrived from medical school. An area in which you can make a real difference to your patients’ care is communication — this rotation is, alas, an opportunity to practice your breaking-bad-news skills. It is also good training in explaining procedures, diagnosis, and management, all of which are common fodder of the clinical skills assessment. No-one expects you to make a diagnosis of Rocky Mountain Spotted Fever, but simply to develop your skills as a clinician, and become confident in differentiating the sick from the well. Make the most of your general medicine placement: ask questions and absorb as many pearls of wisdom from the consultants as you can. 1. It’s all about the history. …

Tu1482 High Definition White Light Endoscopy and I-SCAN for in-Vivo Characterisation of Small Colonic Polyps: No Need to Push the Button

Introduction: Despite advances in endoscope technology there is still a significant miss rate of neoplastic lesions during gastroscopy. Mucosal views are frequently impaired by residual bubbles and mucus. Method: We conducted an RCT in 126 patients attending for routine gastroscopy. Subjects were randomised in a 1:1:1ratio to receive a pre-procedure drink of water, simeticone and n-acetylcysteine (Group A), water alone (Group B) or nopreparation (Group C). Study endoscopists were blinded to group allocation. 4 digital images were taken at pre-defined locations during the procedure – lower oesophagus, upper body, antrum & fundus. Images were rated for mucosalvisibility (MV) using a 4 point scale (1 = best, 4 = worst) by 4 blinded experienced endoscopists. Primary outcome measure was mean MV score. Secondary outcome measures were procedure duration and volume of flush required to achieve adequate mucosal views. Results: Groups were well matched for age, gender or indication for endoscopy. Mean MV score for group A was significantly better than for group B and group C (p < 0.001 for both comparisons), with no significant difference between groups B and C (p=0.541). Interobserver agreement of MV scores was good (mean kappa 0.464).Mean volume of flush required to achieve adequate mucosal views was significantly lower in group A than group B(p=0.001), and group C (P<0.001). There was no significant difference in mean flush volume between groups B & C(p=0.583). Procedure duration did not differ significantly between the groups.Subgroup analysis of MV scores at each location demonstrated significantly better mucosal visibility in group A compared to group B and group C at all locations (p<0.0025 for all comparisons).Group A -Simeticone/NACB –WaterC – Nopreparation Mean Mucosal Visibility (MV) Score(range 1-4)1.35 2.11 2.21Mean Procedure duration (sec) 309 352 334Mean Volume of flush (ml) 2.0 31.5 39.2 Conclusion: A pre-procedure drink containing simeticone and n-acetlycysteine significantly improves mucosal visibility during routine gastroscopy and reduces the need for flushes during the procedure. This may improve detection of early neoplasia and other pathology during gastroscopy. Subanalysis of separate locations demonstrates significant benefit inthe lower oesophagus, demonstrating potential benefit in Barrett’s surveillance procedures.

Tu1962 Prospective Comparison of FICE and I-SCAN for in-Vivo Characterisation of Small Colonic Polyps

a conventional image, the lesion was each observed by NBI magnification. The diagnosis of NBI magnification was based on Sano’s classification. Also irregular findings of microvessels including “caliber change of microvessel” (CCM), “long irregular vessel” (LIV) and “decline of microvessel density” (DMD) were analyzed. When type V pit pattern was suspected, the lesion was observed after crystal-violet dye-stain. The diagnosis of chromoendoscopic magnification was based on Kudo’s classification. Both capillary pattern and pit pattern were compared with final histological diagnosis. This study was performed retrospectively and consecutively. Histological diagnosis on resected specimen was determined according to Vienna classification. Submucosal massively invasive cancer (SM-M) was defined as an invasive depth greater than 1000 m. Results: As to histological diagnoses, there were 380 intramucosal cancers, 60 submucosal slightly invasive cancers, and 81 cancers with submucosal massively invasion. The values of the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) and accuracy of type IIIB for the diagnosis of SM-M were 70.4%, 98.6%, 90.5%, 94.8% and 94.3%, respectively. Those of VI highly irregular and VN were 81.5%, 98.4%, 90.4%, 96.7% and 95.8%, respectively. Type IIIB was observed in 19 (73.1%) of 26 protruded type SM-M, 8 (40.0%) of 20 flat type SM-M and 30 (85.7%) of 35 depressed type SM-M. The values of specificity of CCM, LIV and DMD for the diagnosis of SM-M were 99.1%, 99.8% and 99.5%, respectively. CCM was observed in 14 (51.9%) of 26 protruded type SM-M. And DMD were observed in 23 (67.6%) of 35 depressed type SM-M. Conclusion: NBI magnification would have clinical advantage to diagnose the invasion depth of early colorectal cancers. Submucosal massively invasive cancers had characteristic irregular findings that depended on the morphological type. These irregular findings had high specificity for the diagnosis of submucosal massively invasive cancers. Tu1482 High Definition White Light Endoscopy and I-SCAN for in-Vivo Characterisation of Small Colonic Polyps: No Need to Push the Button Peter J. Basford*, Gaius R. Longcroft-Wheaton, Pradeep Bhandari Gastroenterology, Portsmouth Hospitals NHS Trust, Portsmouth, United Kingdom Introduction: Standard definition white light endoscopy is inadequate for in-vivo characterisation of small colonic polyps. Chromoendoscopy and electronic imaging techniques are shown to improve accuracy. The ASGE has identified prediction of polyp surveillance intervals and negative predictive value for adenomatous histology of diminutive recto-sigmoid polyps as key targets for new technologies. High definition white light endoscopy incorporating charge coupled device chips with resolution in excess of 1 million pixels are now available but there is little data on their use. Aims&Methods: We aimed to examine the in-vivo characterisation accuracy of high definition white light endoscopy (HDWL) plus a novel electronic imaging modality i-Scan (Pentax, Japan). Patients undergoing colonoscopy through the UK Bowel Cancer Screening Programme were prospectively recruited. All colonoscopies were performed by a single expert endoscopist with extensive experience in in-vivo diagnosis. Procedures were performed with Pentax EC-3890Li 1.2 Megapixel HD colonoscopes and EPKi processor. An initial classification & validation exercise was carried out to determine the optimum i-Scan settings for in-vivo diagnosis, and to develop a novel in-vivo diagnosis assessment tool. All polyps 10mm in size were assessed sequentially with HDWL and i-Scan. Optical magnification was not used. Predicted histology (non-neoplastic, adenoma, cancer) was recorded for both modalities and compared to the final histopathological diagnosis as reported by an expert gastrointestinal pathologist. Predictions were rated as high or low confidence assessments. Results were analysed for sensitivity and specificity for neoplasia, overall accuracy, and negative predictive value for rectosigmoid polyps 5mm as recommended by the ASGE PIVI statement. Results: 84 patients were recruited, in whom 209 polyps 10mm were included. Mean polyp diameter was 4.3mm, median 4mm. 134 polyps were neoplastic and 75 non-neoplastic. There were no significant differences in sensitivity (95.5% vs 97.0%) and specificity (89.3% vs 90.7%) for neoplasia and overall diagnostic accuracy (93.3% vs 94.7%) between HDWL and i-Scan. Negative predictive value for adenomatous histology of rectosigmoid polyps 5mm was 100% with both modalities. Polyp surveillance intervals using in-vivo assessment of diminutive polyps were correct in 95% and 97% of patients with HDWL and i-Scan respectively. Conclusion: 1) Excellent in vivo diagnostic accuracy, in excess of 90% can be achieved with HDWL alone.2) No significant gains in accuracy over HDWL were noted with i-Scan when used with a 1.2Megapixel HD colonoscope therefore, there is no need to push the button or spray dye to improve accuracy. 3) Both HDWL and i-Scan fulfill the ASGE criteria for ‘resect and discard’ and ‘do not resect’ strategies for diminutive polyps