Dye Spraying Research Articles

Chromoendoscopy and virtual chromoendoscopy for dysplasia screening in patients with ulcerative colitis (systematic review and meta-analysis)

AIM: to compare the diagnostic informativeness of mucosal dye spraying (chromoendoscopy) (CE) and virtual chromoendoscopy (VCE) in detecting dysplasia in patients with a long history ulcerative colitis (UC).MATERIALS AND METHODS: a systematic review and meta-analysis of studies comparing the results of the use of CE and VCE for the diagnosis of colitis-associated dysplasia was performed. The following indicators were evaluated: the frequency of patients with endoscopically detected colitis-associated dysplasia and the frequency of endoscopic diagnosis of colitis-associated dysplasia among the total number of identified lesions. The statistical analysis was carried out using the Review Manager software 5.3RESULTS: the systematic review included 4 studies, analyzing 364 patients in total. In the study groups, there were no statistical differences in patients with endoscopically detected colitis-associated dysplasia and in endoscopic diagnosis of colitis-associated dysplasia among total number of detected colorectal neoplasms (OR = 0.87; 95% CI 0.60–1.27; p = 0.47 and OR = 0.82; 95% CI 0.58–1.18; p = 0.29).CONCLUSION: meta-analysis could not demonstrate a significant difference between CE and VCE. However, additional studies are needed to recognize the role of VCE in the differentiation of neoplastic and non-neoplastic lesions in patients with UC

Dye Chromoendoscopy Outperforms High-Definition White Light Endoscopy in Dysplasia Detection for Patients With Inflammatory Bowel Disease: An Updated Meta-Analysis of Randomized Controlled Trials.

Whether dye spray chromoendoscopy (DCE) adds value in surveillance colonoscopy with high-definition (HD) scopes remains controversial. This updated meta-analysis compares dysplasia detection using DCE and high-definition white light endoscopy (HD-WLE) in patients with inflammatory bowel disease (IBD) undergoing surveillance colonoscopy. A comprehensive search was performed for randomized controlled trials (RCT) comparing HD-WLE and DCE in patients with IBD. The primary outcome was to compare the proportion of patients with at least 1 dysplastic lesion detected by DCE vs HD-WLE. Odds ratios (OR) and 95% confidence intervals (CI) were pooled using the random-effects model, with I2 > 60% indicating substantial heterogeneity. The Grading of Recommendations, Assessment, Development, and Evaluation approach was used to assess the certainty of evidence (CoE). Six RCT involving 978 patients were analyzed (DCE = 479 vs HD-WLE = 499 patients). DCE detected significantly more patients with dysplasia than HD-WLE (18.8% vs 9.4%), OR 1.94 (95% CI 1.21-3.11, I2 = 28%, P = 0.006, high CoE). This remained significant after excluding 2 RCT published as abstracts. A sensitivity analysis excluding a noninferiority RCT with a single experienced operator eliminated the results' heterogeneity, OR 2.46 (95% CI 1.56-3.90, I2 = 0%). Although high-grade dysplasia detection was numerically higher in the DCE group (2.8% vs 1.1%), the difference was statistically insignificant, OR 2.21 (95% CI 0.64-7.62, I2 = 0%, low CoE). Our updated meta-analysis supports DCE as a superior strategy in overall dysplasia detection in IBD, even with HD scopes. When expertise is available, DCE should be considered for surveillance colonoscopy in patients with high-risk IBD, with the acknowledgment that virtual chromoendoscopy shows equivalence in recent studies. Further multicenter trials with multiple endoscopists with varying expertise levels and longer-term outcome data showing a reduction in cancer or cancer-related death are needed.

Usulan Peningkatan Kualitas Produk Urea dengan Metode Six Sigma Pada PT. XYZ

PT. XYZ is a manufacturing company that produces urea fertilizer. The quality of urea fertilizer is influenced by three main parameters, namely H2O content, Biuret, and color. Based on known secondary data in the form of product defect history, in September 2023 product defects will be 12.9%. This research was conducted using the Six Sigma method with the aim of improving overall quality so as to prevent losses in company productivity. The research results show that in the defect category the H2O parameter has a DPMO value of 225834.7 with a sigma value of 2.25, for the biuret parameter it has a sigma value of 2.83 with a DPMO of 91216.7, and for the color parameter it is known that the DPMO value is 562700 or a sigma value of 1.34. then a root cause analysis is carried out using a fishbone diagram to obtain suggestions for improvement. Suggestions for improving Urea Fertilizer products for CTQ H2O include providing training/certification, coordinating with the Utilities section regarding steam, determining the right sampling point, and optimizing vacuum performance. For CTQ Biuret, namely providing training/certification, changing the tonnage in the urea process, paying attention to residence time and controlling the valve to work properly. For CTQ Color, namely providing training/certification, routinely cleaning dye spray filters, determining the right sampling point and routine pump maintenance.

Characteristics of flat-type ulcerative colitis-associated neoplasia on chromoendoscopic imaging with indigo carmine dye spraying.

Despite recent advances in endoscopic equipment and diagnostic techniques, early detection of ulcerative colitis-associated neoplasia (UCAN) remains difficult because of the complex background of the inflamed mucosa of ulcerative colitis and the morphologic diversity of the lesions. We aimed to describe the main diagnostic patterns for UCAN in our cohort, including lateral extension surrounding flat lesions. Sixty-three lesions in 61 patients with flat-type dysplasia that were imaged with dye chromoendoscopy (DCE) were included in this analysis. These DCE images were analyzed to clarify the dye-chromoendoscopic imaging characteristics of flat dysplasia, and the lesions were broadly classified into dysplastic and nondysplastic mucosal patterns. Dysplastic mucosal patterns were classified into two types: small round patterns with round to roundish structures, and mesh patterns with intricate mesh-like structures. Lesions with a nondysplastic mucosal pattern were divided into two major types: a ripple-like type and a gyrus-like type. Of note, 35 lesions (55.6%) had a small round pattern, and 51 lesions (80.9%) had some type of mesh pattern. About 70% of lesions with small round patterns and 49% of lesions with mesh patterns were diagnosed as high-grade dysplasia or carcinoma, while about 30% of lesions with small round patterns and 51% of lesions with mesh patterns were diagnosed as low-grade dysplasia. When a characteristic mucosal pattern, such as a small round or mesh pattern, is found by DCE, the possibility of UCAN should be considered.

Incremental Detection Rate of Dysplasia and Sessile Serrated Polyps/Adenomas Using Narrow-Band Imaging and Dye Spray Chromoendoscopy in Addition to High-Definition Endoscopy in Patients with Long-Standing Extensive Ulcerative Colitis: Segmental Tandem Endoscopic Study.

High-definition (HD) endoscopy is recommended in surveillance colonoscopy for detecting dysplasia in patients with ulcerative colitis (UC). Dye-spray chromoendoscopy (DCE) and narrow-band imaging (NBI) are often used as adjunctive techniques of white-light endoscopy (WLE) in real-world practice. However, the incremental detection ability of DCE and NBI added to HD-WLE for dysplasia and serrated lesions has not yet been evaluated using tandem endoscopy in patients with long-standing extensive UC. We enrolled patients with extensive UC for >8 years who were in clinical remission (partial Mayo score < 2) at the Samsung Medical Center in Seoul, Republic of Korea. HD-WLE was performed first. Subsequently, HD-NBI and HD-DCE with indigo carmine were performed using the segmental tandem colonoscopy technique. A total of 40 patients were eligible, and data obtained from 33 patients were analyzed. The incremental detection rates (IDRs) for dysplasia and serrated lesions were calculated. HD-WLE detected three dysplasia and five sessile serrated adenomas/polyps (SSAs/Ps). HD-NBI and HD-DCE did not detect additional dysplasia (IDR = 0%; 95% confidence interval (CI): 0-56.2%). HD-NBI identified one missed SSA/P (IDR = 7.7%; 95% CI: 1.4-33.3%), and HD-DCE detected seven missed SSAs/Ps (IDR = 53.9%; 95% CI: 29.1-76.8%). Logistic regression found that HD-DCE increased the detection of SSAs/Ps compared to HD-WLE and/or HD-NBI (odds ratio (OR) = 3.16, 95% CI: 0.83-11.92, p = 0.08). DCE in addition to HD-WLE improved the detection of SSAs/Ps, but not dysplasia, in patients with long-standing extensive UC.

Pancolonic Dye Spray Chromoendoscopy to Detect and Resect Ill-Defined Neoplastic Lesions in Colonic Inflammatory Bowel Disease.

Pancolonic dye spray chromoendoscopy (DCE) is used as an adjunct to white light endoscopy (WLE) to enhance the detection and delineation of ill-defined neoplastic (dysplastic) lesions in persons with colonic inflammatory bowel diseases (cIBD). We evaluated the utility of DCE as follow-up to high-definition WLE (HD-WLE) to "unmask" and/or facilitate endoscopic resection of neoplastic lesions. We retrospectively studied persons with cIBD who underwent DCE as follow-up to HD-WLE between 2013 and 2020. We describe neoplastic findings and management during HD-WLE and DCE exams and report outcomes from post-DCE surveillance exams. Twenty-four persons were studied (mean age 56.7 ± 13.8 years, 50.0% male, 70.8% ulcerative colitis, mean disease duration 18.0 ± 11.0 years). Overall, 32 visible neoplastic lesions were unmasked during DCE, of which 24 were endoscopically resected. DCE facilitated the diagnosis of two cancers. Among 17 persons referred for evaluation of "invisible" neoplasia (detected in non-targeted biopsies) during HD-WLE, DCE identified neoplastic lesions at the same site in eight persons and a different site in four persons. Among seven persons referred for ill-defined visible neoplasia, DCE facilitated complete endoscopic resection in four individuals, whereas two individuals required colectomy for a diagnosis of cancer. Among 19 individuals with post-DCE surveillance, five developed new visible neoplastic lesions, including one high-grade neoplasia which was completely resected. In our cohort, DCE aided in unmasking invisible neoplasia and facilitated endoscopic resection of ill-defined neoplasia, suggesting that it is a useful surveillance tool in selected persons with cIBD. Large prospective studies are needed to validate these findings.

Image-Enhanced Endoscopy Surveillance of Colon and Pouch Dysplasia in IBD.

Patients with longstanding ulcerative colitis and Crohn's colitis are at risk for developing colorectal cancer and need regular endoscopic surveillance to detect and remove precursor lesions. To do so, different technologies are available. The sources are observational and controlled studies, meta-analysis, and expert consensus articles available on PubMed. The selected materials include articles reporting outcomes of and recommendations on endoscopic surveillance and resection of dysplasia in the gastrointestinal tract, including the ileoanal pouch and the anal transition zone, in patients with inflammatory bowel disease. Incidence and detection rate of dysplasia and cancer with different endoscopic techniques in patients with inflammatory bowel disease. Risk of cancer is proportional to the duration and extent of the disease, and surveillance interval should be tailored on the individual risk in a range of 1 to 5 years. High-definition imaging and virtual chromoendoscopy have improved the detection of dysplasia and are now comparable with conventional dye spray chromoendoscopy. After restorative proctocolectomy with ileoanal pouch, the risk of cancer is modest, but its high mortality warrants endoscopic surveillance. The evidence to guide pouch surveillance is limited, and recently, the first expert consensus provided a framework of recommendations, which include an initial assessment 1 year after surgery and follow-up depending on individual risk factors. The limitation includes scarcity of data on ileoanal pouch surveillance. Virtual chromoendoscopy and high-definition imaging have improved endoscopic surveillance, and more progress is expected with the implementation of artificial intelligence systems.

A168 UTILITY OF FOLLOW-UP PANCOLONIC DYE SPRAY CHROMOENDOSCOPY FOR THE DETECTION AND TREATMENT OF DYSPLASTIC LESIONS IDENTIFIED DURING HIGH-DEFINITION WHITE-LIGHT ENDOSCOPY IN PATIENTS WITH COLONIC INFLAMMATORY BOWEL DISEASE

Abstract Background Patients with inflammatory bowel disease (IBD) involving the colorectum are at higher risk for the development of flat and poorly delineated dysplastic lesions. Pancolonic dye spray chromoendoscopy (DCE) can represent an adjunct to white light endoscopy (WLE) that enhances detection and delineation of such lesions. Aims We evaluated the utility of follow-up DCE for lesion detection and treatment in patients with IBD who had visible (polypoid or flat lesions) or invisible (identified in non-targeted biopsies) dysplasia detected during high-definition (HD)-WLE. Methods We retrospectively studied patients with colonic IBD from The Ottawa Hospital who underwent DCE by a trained endoscopist, as follow-up for dysplasia detected during HD-WLE, over a 7-year time period (2013–2020). We collected demographic and disease-specific variables. Results Twenty-four patients were included (mean age 56.7±13.8 years, 50.0% male, 70.8% ulcerative colitis, mean disease duration 18.0±11.0 years, 70.8% moderate or severe disease activity historically, and 41.7% remote history of dysplasia). Seventeen (70.8%) patients were referred following detection of invisible dysplasia; the remainder (29.2%) were referred for surveillance of poorly defined visible dysplastic lesions. For those referred following detection of invisible dysplasia, DCE identified visible dysplasia at the same site in 8/17 (47.1%) patients, at a different site in 6/17 (35.3%) patients, and no dysplasia in 3/17 (17.6%) patients. DCE identified 1.39±1.50 new visible dysplastic lesions per patient that were not identified on index HD-WLE. DCE upgraded the highest grade of dysplasia and diagnosed colorectal cancer in 2/24 (8.3%) patients, which was missed on index HD-WLE. Endoscopic resection was successful in 23/34 (76.7%) dysplastic lesions identified on DCE. However, DCE was unable to facilitate lesion resection in three patients due to advanced lesion characteristics. Follow-up data was available for 17/24 (70.8%) patients (mean 0.88±0.58 years). Of these patients, 7/17 (41.2%) developed subsequent dysplasia, including 4/17 (23.5%) at a site of prior invisible dysplasia, 2/17 (11.8%) at sites of prior visible dysplasia, and 1/17 (5.88%) at a different site. One of these patients developed high-grade dysplasia requiring resection. Conclusions In this study, DCE is a valuable tool for dysplasia detection and treatment in persons with colonic IBD who have ill-defined dysplasia identified during HD-WLE. Given some patients developed dysplasia following DCE in our cohort, it is important to maintain close follow-up and obtain biopsies around sites of prior invisible and visible dysplasia. Further studies are required to validate our findings. Funding Agencies None

Texture and color enhancement imaging in combination with indigo carmine dye spraying to highlight the border of flat ulcerative colitis–associated neoplasia

A 45-year-old man with long-standing ulcerative colitis (UC) for 20 years was referred to our hospital because of positive horizontal margins after treatment for dysplasia. White light imaging identified whitish mucosa with scarring in the rectum (A). Histopathologic examination of the biopsy specimen revealed p53 overexpression, suggesting UC-associated neoplasia (UCAN). It was difficult to determine the extent of the lesion by using only chromoendoscopy with indigo carmine dye spraying (B), but the combination with texture and color enhancement imaging (TXI) made the boundary clear (C).

P171 PSC/IBD and IBD have similar type and location of colonic lesions, but Dye ChromoEndoscopy (DCE) increases detection rate compared to White Light Endoscopy (WLE)

Abstract Background Inflammatory bowel disease (IBD) increases the risk of colorectal cancer proportionally to the extent and duration of the disease. Moreover, up to 5% of IBD patients have concomitant PSC, an additional risk factor, especially for right colon cancer. To mitigate this risk patients with PSC-IBD undergo stricter annual surveillance colonoscopy. We aimed to analyze differences in incidence, location and type of lesions detected during surveillance colonoscopies in PSC/IBD and only IBD. In addition, we assessed the impact of dye spray chromoendoscopy on detection rates. Methods In a retrospective single-center study, we collected all surveillance colonoscopies performed at Birmingham University Hospital between January 2014 and August 2019. The procedures were divided for patient diagnosis in PSC-IBD or IBD-only. Demographic, clinical, endoscopic and histologic data were retrieved from electronic medical records. Categorical variables are presented as absolute and relative frequencies and compared using chi-square test and Fisher’s exact test. Continuous variables are presented as mean and compared by Student t-test after testing for normality. Results We retrieved 856 colonoscopies from 622 patients, of these 282 colonoscopies were performed in 147 patients with PSC, the remaining 574 in 475 patients with IBD-only. Demographic data are presented in (Table 1). In 64 (22%) colonoscopies in PSC/IBD and 173 (30%) in PSC/IBD at least one lesion was found (p=0.02). The total number of lesions was 70 for PSC/IBD (0.248 lesions per procedure) and 226 for IBD-only (0.394 per procedure) (p=0.02). While these differences were statistically significant, PSC/IBD patients had 58% (1.2 vs 1.9) more colonoscopies, due to the stricter surveillance regimen, thus likely reducing the rate of lesions per procedure (Table 2 and 3). There was no statistically significant difference in histologic type and localization of lesions between the two groups (Table 3). Dye spray chromoendoscopy (DCE) was used in 52% of procedures in the IBD-only group, and 65% of the PSC-IBD. Colonoscopies with DCE were significantly more likely to detect lesions both in PSC-IBD and IBD-only cohorts (both p&amp;lt;0.05). Table 4. Conclusion We found a higher detection rate of colonic lesions in colonoscopies of the general IBD population compared to those PSC-IBD patients, though this might be influenced by the frequency of surveillance. The location and type of polyps were similar between groups. DCE increased the rate of detection compared with no DCE regardless of disease phenotype.

Top tips for using image-enhanced endoscopy during colonoscopy (with videos)

Virtual chromoendoscopy is now a standard feature on all commercially available endoscopes and has nearly replaced dye spray endoscopy. For all practical purposes, we do use virtual chromoendoscopy on a regular basis but are sometimes not sure about the use of a cap, are not confident about the features we see, and have difficulty obtaining high-quality images during colonoscopy. In our continuation of the Top Tips feature, Jonathan Cohen, one of the leading adopters and experts in this field, walks us through his top suggestions on how to make virtual chromoendoscopy seamless, an art, and most importantly, practical during colonoscopy.

S876 Utility of Pancolonic Dye Spray Chromoendoscopy for Dysplasia Detection and Management in Inflammatory Bowel Diseases

S876 Utility of Pancolonic Dye Spray Chromoendoscopy for Dysplasia Detection and Management in Inflammatory Bowel Diseases

Depth diagnosis of early colorectal cancer: Magnifying chromoendoscopy or image enhanced endoscopy with magnification?

Depth diagnosis is extremely crucial in making a treatment choice between endoscopic resection and surgery in the early stages of cancers. Among several imaging modalities, we use magnifying endoscopy to diagnose lesions by close observation of the findings at mucosal surface layer. In combination with topical staining, magnifying endoscopy enables us to assess the definite pit structure, which referred to as magnifying chromoendoscopy (MCE). The pit pattern classification by MCE was proposed and is now widely accepted as the standard diagnostic criteria for colorectal lesions. Meanwhile, image enhanced endoscopy (IEE) represented by narrow-band imaging was developed to improve the visibility of surface and vascular findings without dyeing. Recent collaborative work performed by endoscopic experts in Japan yielded the unified diagnostic criteria, the Japan NBI Expert Team (JNET) classification, based on the findings of IEE with magnification. In this review, focusing on MCE and IEE with magnification, we aimed to give an outline of the pit pattern classification and the JNET classification, and further discuss their accuracy rate of depth diagnosis of early colorectal lesions by performing a review of the related literature. Both modalities have a high accuracy rate of nearly 90% for depth diagnosis. IEE with magnification is an ideal modality because it helps observe lesions without dye spraying; however, lesions with JNET type 2B have an inadequate diagnostic ability, which should be complemented by MCE. We conclude that accurate diagnosis is possible by examining lesions using both modalities properly to overcome the limitations of each modality.

Using methylene blue spray intraoperatively to perform safe thyroidectomy

BackgroundRecurrent laryngeal nerve (RLN) injury and hypoparathyroidism are serious complications following thyroidectomy. Minimizing these complications is important to avoid a destructive life-long handicap.AimOur goal was to decrease the incidence of intraoperative mishaps by spraying methylene blue dye on thyroid tissue and the tissues nearby.Patients and methodsThis is a prospective study that included 90 patients who underwent primary thyroid surgery for various thyroid diseases, with total thyroidectomy done in all. The patients were divided into two groups: methylene blue group included 45 patients who underwent surgery using methylene blue technique, and conventional group included 45 patients who underwent surgery using the conventional technique. Spraying of 0.5 ml of methylene blue stain (normal saline) (2 : 8) following superior pole ligation was done. Thyroid tissue of a lobe and perilobar area were exposed to the methylene blue dye spraying, with identification and evaluation of the RLN and parathyroid tissues.ResultsRLN and inferior thyroid artery stayed white in color in every case, but other tissues have been stained by blue color, with different times of fading out. Parathyroid glands stained for 3 min before fading out. Time for wash-out of thyroid gland was 15 min, whereas fading out time for other tissues, such as perithyroid tissues, tendinous, and lipoid structures was ∼25 min.ConclusionThis research aims to show the efficacy of methylene blue spraying as a safe procedure for identification of different important structures in close relation with the operative field such as RLN and parathyroid glands intraoperatively to do safe thyroidectomy.

Endoscopic Recognition and Management Strategies for Malignant Colorectal Polyps: Recommendations of the US Multi-Society Task Force on Colorectal Cancer.

Endoscopic Recognition and Management Strategies for Malignant Colorectal Polyps: Recommendations of the US Multi-Society Task Force on Colorectal Cancer.

Association between dietary sugar intake and colorectal adenoma among cancer screening examinees in Japan.

Although intake of highly sugary foods is considered to be a potential risk factor for colorectal cancer through hyperinsulinemia, the association of sugar intake and colorectal adenoma, a precursor lesion to most colorectal cancer, is poorly understood, particularly in Asian populations. We undertook a cross‐sectional study in a Japanese population to investigate the association between dietary sugar intake and the prevalence of colorectal adenoma. Study subjects were selected from participants who underwent magnifying colonoscopy with dye spraying as part of a cancer screening program and who responded to a self‐administered questionnaire before the colonoscopy. A total of 738 cases with colorectal adenoma and 697 controls were enrolled. Dietary intakes of glucose, fructose, galactose, sucrose, maltose, lactose, and total sugars (sum of these six mono‐ or disaccharides) were calculated from a food frequency questionnaire, and divided into quartiles based on the distribution among controls. Odds ratios and 95% confidence intervals of colorectal adenoma were estimated using unconditional logistic regression models, with adjustment for potential confounding factors. Total sugar intake was not significantly associated with the prevalence of colorectal adenoma (odds ratio for the highest intake group compared to reference group = 1.18; 95% confidence interval, 0.81‐1.73; P for trend = .34). Furthermore, no statistically significant positive associations were observed for any of the six mono‐ or disaccharides. Findings were similar on additional analyses by site, size, and number of adenomas. Our findings do not support an association between high sugar intake and increased odds ratios of colorectal adenoma.

Cold snare polypectomy in combination with a traction device for resection of a colonic adenoma partially extending into a diverticulum.

Cold snare polypectomy in combination with a traction device for resection of a colonic adenoma partially extending into a diverticulum.

Identification of Recurrent Laryngeal Nerve and Parathyroid Glands Intraoperatively by Methylene Blue Spraying Technique

Background: Thyroid surgery has been associated with complications ranging from recurrent laryngeal nerve injury, inadvertent para- thyroidectomies to death. Improvement in thyroidectomy techniques have reduced the mortality rate to minimum, while morbidity remained a significant concern. Aims: This study aims to assess a method to identify recurrent laryngeal nerve and localize the parathyroid glands during thyroid surgery by using methylene blue stain which improve outcomes following thyroidectomy.Materials and methods : This a prospective cross- sectional study was performed on 48 adult patients of both sexes who presented to the surgical ward at Salah Al-Deen general hospital in Tikrit city between October 2017 and July 2018. Full medical history was taken and clinical examination was done to those who were suitable for surgery. After indirect larngyoscopic confirmation of normal vocal cord mobility, in addition hospital medical records were obtained including patient’s name, age, gender, residence, nature of thyroid disease, duration of thyroid disease, previous thyroid surgery, family history of thyroid disease and past medical history, relevant investigations like final histopathology ; all were chosen to undergo thyroidectomy, following superior but before inferior thyroid pedicles ligation, methylene blue dye, in a concentration of 2:8 and 1:10 of Methylene Blue: Normal Saline was sprayed over the thyroid lobe and perilobar area, in the region where recurrent laryngeal nerve is predictable to be found. Recurrent laryngeal nerve and parathyroid glands were identified and safe dissection of the thyroid without injuring these structures were ensured. Results: Recurrent laryngeal nerve was not stained in all cases, in contrast to the blue stained adjacent tissue. Within three minutes parathyroid glands washed out the dye and the yellow color was regained. Conclusions: Several techniques of recurrent laryngeal nerve and parathyroid glands identification were established , our study demonstrate that visual delineation of these structures by methylene blue dye spraying during dissection of thyroid is a simple, safe and effective method for localization and injury avoidance to both recurrent laryngeal nerve and parathyroid glands during thyroid surgery.

P010 FIRST SURVEILLANCE COLONOSCOPY FOR INFLAMMATORY BOWEL DISEASE – ARE WE GETTING IT RIGHT FROM THE START?

Abstract Background Surveillance for colorectal cancer (CRC) is necessary in patients with inflammatory bowel disease (IBD). Patients with ulcerative colitis (UC) have a similar CRC risk to those with Crohn’s colitis (CC). British Society of Gastroenterology (BSG) guidelines from 2010 outlined recommendations for screening including surveillance intervals and pancolonic dye spraying with targeted biopsies. We aimed to identify reasons why the first surveillance colonoscopy is not being performed as advised, including the role of poor bowel preparation and disease activity. Methods Retrospective study of all IBD colonoscopies over a 7 year period (2011–2018) across two sites at a tertiary London based hospital trust. 214 patients were identified and exclusion criterion was applied (not first surveillance/diagnosis prior to year 2000/PSC/inadequate data). 93 patients were included for analysis. Results 26 (28.0%) surveillance colonoscopies were performed prior to 10 years of diagnosis (ie. before BSG guideline recommendation). 22 (23.7%) surveillance colonoscopies performed after the recommended interval. Dye spray was performed in only 2 patients (2%). Reasons cited for not dying were only given in 4 (4.3%) cases, and included poor bowel prep or active disease. No reason was given in 87 (93%) cases. Targeted biopsies were performed in 24 (25.8%) patients, with random biopsies in 56 (60.2%) patients. Conclusion The first IBD surveillance colonoscopy is only being performed at the correct time interval in approximately 50% of cases with over a quarter being performed too soon and almost a quarter being performed too late. Pan-colonic dye spray is used in only 2% and targeted biopsies are taken in only 1 in 4 patients. Poor bowel preparation and disease activity do not appear to be limiting factors in the use of dye spray. We conclude that appropriate initial colitis surveillance is not being performed in the majority despite published guidelines. Organisational factors such as sufficient time allocated to dye spray colonoscopy, along with endoscopist skill, may be contributing factors.

P397 Surveillance in ulcerative colitis: Can we predict the risk for intraepithelial neoplasia?

Abstract Background Ulcerative colitis (UC) has been associated with an increased risk of colorectal cancer (CRC). Although dye spray chromoendoscopy showed superiority to standard colonoscopy in surveillance studies, with the availability of higher-resolution colonoscopes, the utility of chromoendoscopy (CE) has been questioned. We aimed to evaluate the risk of intraepithelial neoplasia (IN) after a high-quality screening colonoscopy (making use of CE or random biopsies (RB) and removing all detected lesions) in a population with longstanding UC and to identify potential risk factors for dysplasia incidence. Methods In a previous study, 145 patients with clinically and endoscopic longstanding (≥8 yr) distal/extensive UC without primary sclerosing cholangitis and/or history of IN were prospectively randomised to undergo CE or RB. In this study, after a median follow-up of 5 additional years, we evaluated subsequent IN incidence in these patients, submitted to surveillance colonoscopy. Patients without high-quality surveillance colonoscopy (with good bowel preparation and cecum intubation) using high-definition were excluded. Results One hundred and twenty-one patients were included. Nine had removed adenomas with low-grade dysplasia in the index colonoscopy. Now, in surveillance colonoscopy, we detected 9 (7.4%) IN: low-grade dysplasia was found in 8 (6.6%) patients and a colorectal adenocarcinoma in 1 (0.008%) patient. After multivariate analysis, IN was significantly associated with older age (68 vs. 52 years, p &amp;lt; 0.05) and higher disease duration (26 vs. 20 years, p &amp;lt; 0.05). No association was found between IN and previous detection of IN in screening colonoscopy sex, the CE or RB use in index colonoscopy, extent of disease, The presence of pseudopolyps, smoking habits, familial history of CRC or maintenance therapy for UC. Conclusion In this study, older patients and higher disease duration were associated with a higher risk of IN in surveillance colonoscopy.