Christopher Khor - Academia.edu (original) (raw)

Papers by Christopher Khor

Research paper thumbnail of Asian consensus statements on endoscopic management of walled-off necrosis Part 1: Epidemiology, diagnosis, and treatment

Journal of Gastroenterology and Hepatology, Sep 1, 2016

HI was involved with study conception, study design, creation of the preliminary statements list ... more HI was involved with study conception, study design, creation of the preliminary statements list and the allocated statement, drafting of the manuscript, critical revision of the manuscript, obtaining funding, face-to-face meetings and voting.

Research paper thumbnail of Motorized Spiral Enteroscopy Versus Double Balloon Enteroscopy: A Case-Matched Study in a Multiracial Asian Cohort

Gastrointestinal Endoscopy

Research paper thumbnail of Evaluation of the ex-vivo porcine simulator on EUS-guided cystogastrostomy using lumen-apposing metal stent training

Endoscopic ultrasound, May 2, 2022

Bckground and Objectives: EUS-guided cystogastrostomy is a well-established advanced endoscopic t... more Bckground and Objectives: EUS-guided cystogastrostomy is a well-established advanced endoscopic technique with a steep-learning curve which necessitates an ex-vivo simulator that would allow for adequate training. The aim of this study is to evaluate the feasibility of the model in allowing training for EUS-guided cystogastrostomy using lumen-apposing metal stent (LAMS). Subjects and Methods: The model was created by ROEYA Training Center, Egypt, using native porcine tissue to create fluid collections simulating both cystic and solid lesions. It was designed and tested in advance while the hydrogel was added on-site. The simulator was evaluated prospectively in five training How to cite this article: Ibrahim M, Roshdy N, Taleb A, Alfadda A, Al-Lehibi A, Altonbary A, et al. Evaluation of the ex-vivo porcine simulator on EUS-guided cystogastrostomy using lumen-apposing metal stent training. Endosc Ultrasound 2022;11:201-7.

Research paper thumbnail of Safety and early efficacy of endoscopic sleeve gastroplasty (ESG) for obesity in a multi‐ethnic Asian population in Singapore

JGH Open, 2021

Endoscopic sleeve gastroplasty (ESG) is an alternative nonsurgical treatment option for obesity. ... more Endoscopic sleeve gastroplasty (ESG) is an alternative nonsurgical treatment option for obesity. However, most studies on the utility and efficacy of ESG are derived from the Western population. It is unknown if ESG elicits similar results in Asians with different fat distribution, sociocultural customs, and dietary practices. Our study aims to assess the safety and efficacy of ESG among a multi‐ethnic Asian population.

Research paper thumbnail of Spying a Biliary Stricture Through a Colonoscope in a Patient with Roux-en-Y Hepaticojejunostomy

Gastrointestinal Endoscopy, 2016

Research paper thumbnail of 790 International, Multicentre Prospective Study Comparing Risk Scoring Systems for Patients Presenting With Upper Gastrointestinal Bleeding

Research paper thumbnail of Urgent endoscopy is associated with lower mortality in high-risk but not low-risk nonvariceal upper gastrointestinal bleeding

Endoscopy, 2011

As the high-risk and low-risk groups were determined by pre-endoscopic risk stratification with G... more As the high-risk and low-risk groups were determined by pre-endoscopic risk stratification with Glasgow-Blatchford score, variables which were components of the Glasgow-Blatchford score were not included for univariate analysis in these subgroups.

Research paper thumbnail of Diaphragmatic Breathing Reduces Belching and Proton Pump Inhibitor Refractory Gastroesophageal Reflux Symptoms

Clinical Gastroenterology and Hepatology, 2018

BACKGROUND & AIMS: In patients with gastroesophageal reflux disease (GERD) and excessive belching... more BACKGROUND & AIMS: In patients with gastroesophageal reflux disease (GERD) and excessive belching, most belches are supragastric, and can induce reflux episodes and worsen GERD. Supragastric belching (SGB) might be reduced with diaphragmatic breathing exercises. We investigated whether diaphragmatic breathing therapy is effective in reducing belching and proton pump inhibitor (PPI)-refractory gastroesophageal reflux symptoms. METHODS: We performed a prospective study of 36 consecutive patients with GERD refractory to PPI therapy and a belching visual analogue scale (VAS) score of 6 or more, seen at a gastroenterology clinic at a tertiary hospital in Singapore from April 2015 through October 2016. Patients underwent high-resolution manometry and 24-hour pH-impedance studies while they were off PPIs. Fifteen patients were placed on a standardized diaphragmatic breathing exercise protocol (treatment group) and completed questionnaires at baseline, after diaphragmatic breathing therapy, and 4 months after the therapy ended. Twenty-one patients were placed on a waitlist (control subjects), completed the same questionnaires with an additional questionnaire after their waitlist period, and eventually received diaphragmatic breathing therapy. The primary outcome was reduction in belching VAS by 50% or more after treatment. Secondary outcomes included GERD symptoms (evaluated using the reflux disease questionnaire) and quality of life (QoL) scores, determined from the Reflux-Qual Short Form and EuroQoL-VAS. RESULTS: Nine of the 15 patients in the treatment group (60%) and none of the 21 control subjects achieved the primary outcome (P < .001). In the treatment group, the mean belching VAS score decreased from 7.1-1.5 at baseline to 3.5-2.0 after diaphragmatic breathing therapy; in the control group, the mean VAS score was 7.6-1.1 at baseline and 7.4-1.3 after the waitlist period. Eighty percent of patients in the treatment group significantly reduced belching frequency compared with 19% in control subjects (P [ .001). Treatment significantly reduced symptoms of GERD (the mean reflux disease questionnaire score decreased by 12.2 in the treatment group and 3.1 in the control group; P [ .01). The treatment significantly increased QoL scores (the mean Reflux-Qual Short Form score increased by 15.4 in the treatment group and 5.2 in the control group; P [ .04) and mean EuroQoL-VAS scores (15.7 increase in treatment group and 2.4 decrease in the control group). These changes were sustained at 4 months after treatment. In the end, 20 of the 36 patients who received diaphragmatic breathing therapy (55.6%), all with excessive SGB, achieved the primary outcome. CONCLUSIONS: In a prospective study, we found a standardized protocol for diaphragmatic breathing to reduce belching and PPI-refractory gastroesophageal reflux symptoms, and increase QoL in patients with PPI-refractory GERD with belching-especially those with excessive SGB.

Research paper thumbnail of Mo1303 DOES ENDOSCOPIC ULTRASOUND GUIDED FINE NEEDLE BIOPSY WITH FRANSEEN TIP DESIGN (EUS-FNB) PROVIDE MORE TISSUE THAN FINE NEEDLE ASPIRATION (FNA)? RESULTS OF A RANDOMIZED CONTROLLED STUDY

Gastrointestinal Endoscopy, 2018

In dicots, the key developmental process by which immature plastids differentiate into photosynth... more In dicots, the key developmental process by which immature plastids differentiate into photosynthetically competent chloroplasts commences in the shoot apical meristem (SAM), within the shoot apex. Using laser-capture microdissection and single-cell RNA sequencing methodology, we studied the changes in the transcriptome along the chloroplast developmental pathway in the shoot apex of tomato seedlings. The analysis revealed the presence of transcripts for different chloroplast functions already in the stem cell-containing region of the SAM. Thereafter, an en masse up-regulation of genes encoding for various proteins occurs, including chloroplast ribosomal proteins and proteins involved in photosynthesis, photoprotection and detoxification of reactive oxygen species. The results highlight transcriptional events that operate during chloroplast biogenesis, leading to the rapid establishment of photosynthetic competence.

Research paper thumbnail of Impact of COVID-19 on Endoscopy Training: Perspectives from a Global Survey of Program Directors and Endoscopy Trainers

Clinical Endoscopy, 2021

Background/Aims: The coronavirus disease of 2019 (COVID-19) pandemic has impacted the training of... more Background/Aims: The coronavirus disease of 2019 (COVID-19) pandemic has impacted the training of medical trainees internationally. The aim of this study was to assess the global impact of COVID-19 on endoscopy training from the perspective of endoscopy trainers and to identify strategies implemented to mitigate the impact on trainee education.Methods: Teaching faculty of gastroenterology (GI) training programs globally were invited to complete a 36-question web-based survey to report the characteristics of their training programs and the impact of COVID-19 on various aspects of endoscopy training, including what factors decisions were based on.Results: The survey response rate was 52.6% (305 out of 580 individuals); 92.8% reported a negative impact on endoscopy training, with suspension of elective procedures (77.1%) being the most detrimental factor. Geographic variations were noted, with European programs reporting the lowest percentage of trainee participation in procedures. A h...

Research paper thumbnail of Clinical guidance on endoscopic management of colonic polyps in Singapore

Singapore Medical Journal, 2020

Colonoscopy with endoscopic resection of detected colonic adenomas interrupts the adenoma-carcino... more Colonoscopy with endoscopic resection of detected colonic adenomas interrupts the adenoma-carcinoma sequence and reduces the incidence of colorectal cancer and cancer-related mortality. In the past decade, there have been significant developments in instruments and techniques for endoscopic polypectomy. Guidelines have been formulated by various professional bodies in Europe, Japan and the United States, but some of the recommendations differ between the various bodies. An expert professional workgroup under the auspices of the Academy of Medicine, Singapore, was set up to provide guidance on the endoscopic management of colonic polyps in Singapore. A total of 23 recommendations addressed the following issues: accurate description and diagnostic evaluation of detected polyps; techniques to reduce the risk of post-polypectomy bleeding and delayed perforation; the role of specific endoscopic resection techniques; the histopathological criteria for defining endoscopic cure; and the rol...

Research paper thumbnail of 173 Outcomes of an International Multi-Centered Registry on Eus-Guided Gallbladder Drainage in Patients That Are Unfit for Cholecystectomy

Gastrointestinal Endoscopy, 2018

Background: Single balloon enteroscopy (SBE) is primarily utilized in evaluation of obscure gastr... more Background: Single balloon enteroscopy (SBE) is primarily utilized in evaluation of obscure gastrointestinal bleeding (OGIB). However 40-50% of patients with OGIB experience continued GI blood loss following SBE, in part due to missed lesions.

Research paper thumbnail of Outcomes of an international multicenter registry on EUS-guided gallbladder drainage in patients at high risk for cholecystectomy

Endoscopy International Open, 2019

Background and study aims The aim of the current study was to review the outcomes of a large-scal... more Background and study aims The aim of the current study was to review the outcomes of a large-scale international registry on endoscopic ultrasound-guided gallbladder drainage (EGBD) that encompasses different stent systems in patients who are at high-risk for cholecystectomy. Patients and methods This was a retrospective international multicenter registry on EGBD created by 13 institutions around the world. Consecutive patients who received EGBD for several indications were included. Outcomes include technical and clinical success, unplanned procedural events (UPE), adverse events (AEs), mortality, recurrent cholecystitis and learning curve of the procedure. Results Between June 2011 and November 2017, 379 patients were recruited to the study. Technical and clinical success were achieved in 95.3 % and 90.8 % of the patients, respectively. The 30-day AE rate was 15.3 % and 30-day mortality was 9.2 %. UPEs were significantly more common in patients with EGBD performed for conversion o...

Research paper thumbnail of The Application of New Diagnostic and Therapeutic Techniques in A Case of Zollinger-Ellison Syndrome

Gastrointestinal Endoscopy, 2016

A novel reusable endoscope (Olympus Corp.) with an integral motor was developed for rotating a di... more A novel reusable endoscope (Olympus Corp.) with an integral motor was developed for rotating a disposable short spiral overtube mounted on the insertion tube portion. The drive motor located in the endoscope handle is activated via foot pedals and controls the direction and speed of rotation of a coupler located in the middle of the endoscope's insertion tube. The rotation coupler is the only portion of the endoscope that rotates; the distal and proximal portions of the insertion tube do not rotate. Other than the presence of the drive motor and the rotation coupler, the endoscope design is the same as that of conventional flexible endoscopes. The single-use spiral assembly is comprised of corrugated tubing with an atraumatic plastic spiral bonded to its exterior. It relies on rotation of the spiral component to "pleat" or "unpleat" the bowel either on or off the insertion tube as the spiral thread rotates in a clockwise or counterclockwise direction, respectively. The operator can monitor how much torque is being applied to the small bowel by observing the system's "visual force gauge". This display provides the operator with a visual indication of the direction of rotation and the force of rotation throughout the examination. The clinical case represents the first use of this device in humans. Enteroscopy was indicated for treatment of angiodysplasias in the jejunum identified by small bowel capsule endoscopy in a 48 year old patient with iron deficiency anaemia. The novel motorized enteroscope could be smoothly inserted approximately 250 cm distal of the ligament of Treitz within 20 minutes. The technique allowed controlled movement of the tip of the endoscope and it provided an excellent visualization of the intubated small bowel. An angiodysplasia was detected and treated with argon plasma coagulation. Careful removal of the endoscope with counterclockwise rotation of the spiral revealed no iatrogenic mucosal trauma. No adverse events were registered.

Research paper thumbnail of 1160 Treatment of Iatrogenic Duodenal Perforation Using Over the Scope Clip

Gastrointestinal Endoscopy, 2017

A 70 year old Caucasian male with history of laparoscopic adjustable gastric banding for morbid o... more A 70 year old Caucasian male with history of laparoscopic adjustable gastric banding for morbid obesity about four years prior to admission, presented to our hospital with complaint of progressive malaise, intermittent upper abdominal pain, poor appetite, and low grade fever for past three weeks. He found to have leukocytosis. CT of the abdomen revealed significant thickening and a loculated fluid collection in the distal anterior gastric wall causing extrinsic compression of the pylorus consistent with suppurative gastritis and gastric wall abscess. He underwent esophagogastro-duodenoscopy which revealed a large partially obstructive buldge along the lesser curvature. Endoscopic ultrasound revealed a well-defined 3 to 4 cm intramural fluid collection in distal stomach. Fine needle aspiration was performed and the frankly purulent aspirate was sent for culture, gram stain, and sensitivity. After fine needle aspiration of abscess, saline was instilled into the cavity to facilitate the stent placement. Under fluoroscopic guidance, a guidewire was advanced into the cavity and a tract was created using a needle-knife. Tract was dilated with an 8 mm dilation balloon and a double pigtail stent was placed in the cavity with success. Follow up enteroscopy 5 weeks later, revealed the partially eroded adjustable gastric band into the cardia and resolution of the previously noted bulge in antrum. The pigtail stent placed during last exam was not seen in the stomach and proximal jejunum and X-Ray didn't show the stent. Patient was referred to surgery for removal of eroded adjustable gastric band. In summary, Endoscopic ultrasound guided abscess drainage is a useful treatment option for management of intra-mural gastric abscess.

Research paper thumbnail of 1035 Delayed Endoscopic Closure of a Giant Gastric Perforation

Gastrointestinal Endoscopy, 2017

Background: Small iatrogenic perforation can be treated successfully using endoscopy. However, pe... more Background: Small iatrogenic perforation can be treated successfully using endoscopy. However, perforation can be large. We describe a case of delayed endoscopic closure of giant gastric perforation using multiple over the scope clips. Case: A 72-year-old man had an upper endoscopy because of hematemesis. A bleeding large mass was found in the distal esophagus and was treated using spraying hemostasis powder. During spraying, the patient moved abruptly and developed severe abdominal distention and acute respiratory failure. An abdominal X-Ray after stabilization showed pneumoperitoneum. The patient was treated conservatively with intravenous antibiotics and nil per oral because of his other co-morbidities. Although he improved clinically, the abdominal distention persisted. Hence, a computerized tomogram was performed 3 days later, which showed a large defect in the anterior aspect of the mid stomach. He was referred for endoscopic closure and herein; we describe the technique adopted for endoscopic treatment. Endoscopic technique: First, we evacuated the pneumoperitoneum before performing endoscopy. This may prevent gastric distention and air embolism during procedure. We used Co2 insufflation to prevent recurrent pneumoperitoneum. Secondly, after assessing the morphology of the perforation, we washed it thoroughly with saline. This

Research paper thumbnail of The clinical evaluation of needle-based confocal laser endomicroscopy (nCLE) in the assessment of the pancreatic cystic lesions (PCL). A pilot study

Pancreatology, 2016

next arteries: lienalis (46), gastroduodenalis (51), hepatic (6), pancreatoduodenalis (5), left g... more next arteries: lienalis (46), gastroduodenalis (51), hepatic (6), pancreatoduodenalis (5), left gastric (2). They are manifestated as recurrent wirsungorragia or arrosive duodenal bleeding. 36 selective arterial embolisations of PA by coils were performed with definitive haemostasis (94,4%) and partial success (5,6%). All patients are survived. In other 74 cases (67,3%) we performed next open procedures: pancreatoduodenectomy (33); distal pancreatic resection with splenectomy (18), including combined gastric or colon resection (72,2%); pancreatic head resection (6), suture or PA resection (17). 3 patients (4,1%) died after open surgery. Conclusion: Interventional radiology is a successful way in treatment of intestinal bleeding due to pseudoaneuryzms after acute necritizing pancreatitis. Digestive organ's resections with their arrosive defects in one block with pancreas may be performed effectively in the specialized surgical centres with good short-term results.

Research paper thumbnail of The impact of the coronavirus disease 2019 pandemic on gastroenterologists in Southeast Asia: A mixed‐methods study

Abstract: Background and Aim: The coronavirus disease 2019 pandemic has impacted gastroenterology... more Abstract: Background and Aim: The coronavirus disease 2019 pandemic has impacted gastroenterology practices worldwide; however, its protracted effects within Southeast Asia were unknown. The primary aim of the study was to determine the impact of the pandemic on clinical demands including burnout among gastroenterologists within the region. The secondary aim was to identify risk factors for burnout and determine regional stressors. Methods: This was a mixed‐methods study. Gastroenterologists were surveyed electronically between September 1 and December 7, 2020, via gastroenterology and endoscopy societies of Brunei, Indonesia, Malaysia, Philippines, Singapore, and Thailand. Quantitative and qualitative data were collected. The 22‐item Maslach Burnout Inventory‐Human Services Survey (MBI‐HSS) was used to detect burnout. Quantitative data were non‐parametric; non‐parametric methods were used for statistical comparisons. Logistic regression was used to determine risk factors for burnou...

Research paper thumbnail of Burnout and work-related stressors in gastroenterology: a protocol for a multinational observational study in the ASEAN region

BMJ Open Gastroenterology, 2020

BackgroundClinician burnout is an important occupational hazard that may be exacerbated by the no... more BackgroundClinician burnout is an important occupational hazard that may be exacerbated by the novel COVID-19 pandemic. Within Southeast Asia, burnout in gastroenterology is understudied. The primary objective of this study is to estimate the prevalence of burnout symptoms within gastroenterology, in member states of the Associations of Southeast Asian Nations (ASEAN), during and after the COVID-19 pandemic. The secondary objective is to identify work-related stressors that contribute to burnout in ASEAN gastroenterologists.Methods and analysisThis is an observational study that will use anonymised online surveys to estimate the prevalence of burnout symptoms at two time points: during the COVID-19 pandemic in 2020 and in 2022 (assumed to be after the pandemic). Gastroenterologists from Singapore, Malaysia, Thailand, Indonesia, Philippines and Brunei will be invited to participate in the online survey through their national gastroenterology and endoscopy societies. Burnout will be a...

Research paper thumbnail of Consensus guidelines on the role of cholangioscopy to diagnose indeterminate biliary stricture

HPB, 2021

BACKGROUND Indeterminate strictures pose a therapeutic dilemma. In recent years, cholangioscopy h... more BACKGROUND Indeterminate strictures pose a therapeutic dilemma. In recent years, cholangioscopy has evolved and the availability of cholangioscopy has increased. However, the position of cholangioscopy in the diagnostic algorithm to diagnose malignancy have not been well established. We aim to develop a consensus statement regarding the clinical role of cholangioscopy in the diagnosis of indeterminate biliary strictures. METHODS The international experts reviewed the evidence and modified the statements using a three-step modified Delphi method. Each statement achieves consensus when it has at least 80% agreement. RESULTS Nine final statements were formulated. An indeterminate biliary stricture is defined as that of uncertain etiology under imaging or tissue diagnosis. When available, cholangioscopic assessment and guided biopsy during the first round of ERCP may reduce the need to perform multiple procedures. Cholangioscopy are helpful in diagnosing malignant biliary strictures by both direct visualization and targeted biopsy. The absence of disease progression for at least 6 months is supportive of non-malignant etiology. Direct per-oral cholangioscopy provides the largest accessory channel, better image definition, with image enhancement but is technically demanding. Image enhancement during cholangioscopy may increase the diagnostic sensitivity of visual impression of malignant biliary strictures. Cholangioscopic imaging characteristics including tumor vessels, papillary projection, nodular or polypoid mass, and infiltrative lesions are highly suggestive for neoplastic/malignant biliary disease. The risk of cholangioscopy related cholangitis is higher than in standard ERCP, necessitating prophylactic antibiotics and ensuring adequate biliary drainage. Per-oral cholangioscopy may not be the modality of choice in the evaluation of distal biliary strictures due to inherent technical difficulties. CONCLUSION Evidence supports that cholangioscopy has an adjunct role to abdominal imaging and ERCP tissue acquisition in order to evaluate and diagnose indeterminate biliary strictures.

Research paper thumbnail of Asian consensus statements on endoscopic management of walled-off necrosis Part 1: Epidemiology, diagnosis, and treatment

Journal of Gastroenterology and Hepatology, Sep 1, 2016

HI was involved with study conception, study design, creation of the preliminary statements list ... more HI was involved with study conception, study design, creation of the preliminary statements list and the allocated statement, drafting of the manuscript, critical revision of the manuscript, obtaining funding, face-to-face meetings and voting.

Research paper thumbnail of Motorized Spiral Enteroscopy Versus Double Balloon Enteroscopy: A Case-Matched Study in a Multiracial Asian Cohort

Gastrointestinal Endoscopy

Research paper thumbnail of Evaluation of the ex-vivo porcine simulator on EUS-guided cystogastrostomy using lumen-apposing metal stent training

Endoscopic ultrasound, May 2, 2022

Bckground and Objectives: EUS-guided cystogastrostomy is a well-established advanced endoscopic t... more Bckground and Objectives: EUS-guided cystogastrostomy is a well-established advanced endoscopic technique with a steep-learning curve which necessitates an ex-vivo simulator that would allow for adequate training. The aim of this study is to evaluate the feasibility of the model in allowing training for EUS-guided cystogastrostomy using lumen-apposing metal stent (LAMS). Subjects and Methods: The model was created by ROEYA Training Center, Egypt, using native porcine tissue to create fluid collections simulating both cystic and solid lesions. It was designed and tested in advance while the hydrogel was added on-site. The simulator was evaluated prospectively in five training How to cite this article: Ibrahim M, Roshdy N, Taleb A, Alfadda A, Al-Lehibi A, Altonbary A, et al. Evaluation of the ex-vivo porcine simulator on EUS-guided cystogastrostomy using lumen-apposing metal stent training. Endosc Ultrasound 2022;11:201-7.

Research paper thumbnail of Safety and early efficacy of endoscopic sleeve gastroplasty (ESG) for obesity in a multi‐ethnic Asian population in Singapore

JGH Open, 2021

Endoscopic sleeve gastroplasty (ESG) is an alternative nonsurgical treatment option for obesity. ... more Endoscopic sleeve gastroplasty (ESG) is an alternative nonsurgical treatment option for obesity. However, most studies on the utility and efficacy of ESG are derived from the Western population. It is unknown if ESG elicits similar results in Asians with different fat distribution, sociocultural customs, and dietary practices. Our study aims to assess the safety and efficacy of ESG among a multi‐ethnic Asian population.

Research paper thumbnail of Spying a Biliary Stricture Through a Colonoscope in a Patient with Roux-en-Y Hepaticojejunostomy

Gastrointestinal Endoscopy, 2016

Research paper thumbnail of 790 International, Multicentre Prospective Study Comparing Risk Scoring Systems for Patients Presenting With Upper Gastrointestinal Bleeding

Research paper thumbnail of Urgent endoscopy is associated with lower mortality in high-risk but not low-risk nonvariceal upper gastrointestinal bleeding

Endoscopy, 2011

As the high-risk and low-risk groups were determined by pre-endoscopic risk stratification with G... more As the high-risk and low-risk groups were determined by pre-endoscopic risk stratification with Glasgow-Blatchford score, variables which were components of the Glasgow-Blatchford score were not included for univariate analysis in these subgroups.

Research paper thumbnail of Diaphragmatic Breathing Reduces Belching and Proton Pump Inhibitor Refractory Gastroesophageal Reflux Symptoms

Clinical Gastroenterology and Hepatology, 2018

BACKGROUND & AIMS: In patients with gastroesophageal reflux disease (GERD) and excessive belching... more BACKGROUND & AIMS: In patients with gastroesophageal reflux disease (GERD) and excessive belching, most belches are supragastric, and can induce reflux episodes and worsen GERD. Supragastric belching (SGB) might be reduced with diaphragmatic breathing exercises. We investigated whether diaphragmatic breathing therapy is effective in reducing belching and proton pump inhibitor (PPI)-refractory gastroesophageal reflux symptoms. METHODS: We performed a prospective study of 36 consecutive patients with GERD refractory to PPI therapy and a belching visual analogue scale (VAS) score of 6 or more, seen at a gastroenterology clinic at a tertiary hospital in Singapore from April 2015 through October 2016. Patients underwent high-resolution manometry and 24-hour pH-impedance studies while they were off PPIs. Fifteen patients were placed on a standardized diaphragmatic breathing exercise protocol (treatment group) and completed questionnaires at baseline, after diaphragmatic breathing therapy, and 4 months after the therapy ended. Twenty-one patients were placed on a waitlist (control subjects), completed the same questionnaires with an additional questionnaire after their waitlist period, and eventually received diaphragmatic breathing therapy. The primary outcome was reduction in belching VAS by 50% or more after treatment. Secondary outcomes included GERD symptoms (evaluated using the reflux disease questionnaire) and quality of life (QoL) scores, determined from the Reflux-Qual Short Form and EuroQoL-VAS. RESULTS: Nine of the 15 patients in the treatment group (60%) and none of the 21 control subjects achieved the primary outcome (P < .001). In the treatment group, the mean belching VAS score decreased from 7.1-1.5 at baseline to 3.5-2.0 after diaphragmatic breathing therapy; in the control group, the mean VAS score was 7.6-1.1 at baseline and 7.4-1.3 after the waitlist period. Eighty percent of patients in the treatment group significantly reduced belching frequency compared with 19% in control subjects (P [ .001). Treatment significantly reduced symptoms of GERD (the mean reflux disease questionnaire score decreased by 12.2 in the treatment group and 3.1 in the control group; P [ .01). The treatment significantly increased QoL scores (the mean Reflux-Qual Short Form score increased by 15.4 in the treatment group and 5.2 in the control group; P [ .04) and mean EuroQoL-VAS scores (15.7 increase in treatment group and 2.4 decrease in the control group). These changes were sustained at 4 months after treatment. In the end, 20 of the 36 patients who received diaphragmatic breathing therapy (55.6%), all with excessive SGB, achieved the primary outcome. CONCLUSIONS: In a prospective study, we found a standardized protocol for diaphragmatic breathing to reduce belching and PPI-refractory gastroesophageal reflux symptoms, and increase QoL in patients with PPI-refractory GERD with belching-especially those with excessive SGB.

Research paper thumbnail of Mo1303 DOES ENDOSCOPIC ULTRASOUND GUIDED FINE NEEDLE BIOPSY WITH FRANSEEN TIP DESIGN (EUS-FNB) PROVIDE MORE TISSUE THAN FINE NEEDLE ASPIRATION (FNA)? RESULTS OF A RANDOMIZED CONTROLLED STUDY

Gastrointestinal Endoscopy, 2018

In dicots, the key developmental process by which immature plastids differentiate into photosynth... more In dicots, the key developmental process by which immature plastids differentiate into photosynthetically competent chloroplasts commences in the shoot apical meristem (SAM), within the shoot apex. Using laser-capture microdissection and single-cell RNA sequencing methodology, we studied the changes in the transcriptome along the chloroplast developmental pathway in the shoot apex of tomato seedlings. The analysis revealed the presence of transcripts for different chloroplast functions already in the stem cell-containing region of the SAM. Thereafter, an en masse up-regulation of genes encoding for various proteins occurs, including chloroplast ribosomal proteins and proteins involved in photosynthesis, photoprotection and detoxification of reactive oxygen species. The results highlight transcriptional events that operate during chloroplast biogenesis, leading to the rapid establishment of photosynthetic competence.

Research paper thumbnail of Impact of COVID-19 on Endoscopy Training: Perspectives from a Global Survey of Program Directors and Endoscopy Trainers

Clinical Endoscopy, 2021

Background/Aims: The coronavirus disease of 2019 (COVID-19) pandemic has impacted the training of... more Background/Aims: The coronavirus disease of 2019 (COVID-19) pandemic has impacted the training of medical trainees internationally. The aim of this study was to assess the global impact of COVID-19 on endoscopy training from the perspective of endoscopy trainers and to identify strategies implemented to mitigate the impact on trainee education.Methods: Teaching faculty of gastroenterology (GI) training programs globally were invited to complete a 36-question web-based survey to report the characteristics of their training programs and the impact of COVID-19 on various aspects of endoscopy training, including what factors decisions were based on.Results: The survey response rate was 52.6% (305 out of 580 individuals); 92.8% reported a negative impact on endoscopy training, with suspension of elective procedures (77.1%) being the most detrimental factor. Geographic variations were noted, with European programs reporting the lowest percentage of trainee participation in procedures. A h...

Research paper thumbnail of Clinical guidance on endoscopic management of colonic polyps in Singapore

Singapore Medical Journal, 2020

Colonoscopy with endoscopic resection of detected colonic adenomas interrupts the adenoma-carcino... more Colonoscopy with endoscopic resection of detected colonic adenomas interrupts the adenoma-carcinoma sequence and reduces the incidence of colorectal cancer and cancer-related mortality. In the past decade, there have been significant developments in instruments and techniques for endoscopic polypectomy. Guidelines have been formulated by various professional bodies in Europe, Japan and the United States, but some of the recommendations differ between the various bodies. An expert professional workgroup under the auspices of the Academy of Medicine, Singapore, was set up to provide guidance on the endoscopic management of colonic polyps in Singapore. A total of 23 recommendations addressed the following issues: accurate description and diagnostic evaluation of detected polyps; techniques to reduce the risk of post-polypectomy bleeding and delayed perforation; the role of specific endoscopic resection techniques; the histopathological criteria for defining endoscopic cure; and the rol...

Research paper thumbnail of 173 Outcomes of an International Multi-Centered Registry on Eus-Guided Gallbladder Drainage in Patients That Are Unfit for Cholecystectomy

Gastrointestinal Endoscopy, 2018

Background: Single balloon enteroscopy (SBE) is primarily utilized in evaluation of obscure gastr... more Background: Single balloon enteroscopy (SBE) is primarily utilized in evaluation of obscure gastrointestinal bleeding (OGIB). However 40-50% of patients with OGIB experience continued GI blood loss following SBE, in part due to missed lesions.

Research paper thumbnail of Outcomes of an international multicenter registry on EUS-guided gallbladder drainage in patients at high risk for cholecystectomy

Endoscopy International Open, 2019

Background and study aims The aim of the current study was to review the outcomes of a large-scal... more Background and study aims The aim of the current study was to review the outcomes of a large-scale international registry on endoscopic ultrasound-guided gallbladder drainage (EGBD) that encompasses different stent systems in patients who are at high-risk for cholecystectomy. Patients and methods This was a retrospective international multicenter registry on EGBD created by 13 institutions around the world. Consecutive patients who received EGBD for several indications were included. Outcomes include technical and clinical success, unplanned procedural events (UPE), adverse events (AEs), mortality, recurrent cholecystitis and learning curve of the procedure. Results Between June 2011 and November 2017, 379 patients were recruited to the study. Technical and clinical success were achieved in 95.3 % and 90.8 % of the patients, respectively. The 30-day AE rate was 15.3 % and 30-day mortality was 9.2 %. UPEs were significantly more common in patients with EGBD performed for conversion o...

Research paper thumbnail of The Application of New Diagnostic and Therapeutic Techniques in A Case of Zollinger-Ellison Syndrome

Gastrointestinal Endoscopy, 2016

A novel reusable endoscope (Olympus Corp.) with an integral motor was developed for rotating a di... more A novel reusable endoscope (Olympus Corp.) with an integral motor was developed for rotating a disposable short spiral overtube mounted on the insertion tube portion. The drive motor located in the endoscope handle is activated via foot pedals and controls the direction and speed of rotation of a coupler located in the middle of the endoscope's insertion tube. The rotation coupler is the only portion of the endoscope that rotates; the distal and proximal portions of the insertion tube do not rotate. Other than the presence of the drive motor and the rotation coupler, the endoscope design is the same as that of conventional flexible endoscopes. The single-use spiral assembly is comprised of corrugated tubing with an atraumatic plastic spiral bonded to its exterior. It relies on rotation of the spiral component to "pleat" or "unpleat" the bowel either on or off the insertion tube as the spiral thread rotates in a clockwise or counterclockwise direction, respectively. The operator can monitor how much torque is being applied to the small bowel by observing the system's "visual force gauge". This display provides the operator with a visual indication of the direction of rotation and the force of rotation throughout the examination. The clinical case represents the first use of this device in humans. Enteroscopy was indicated for treatment of angiodysplasias in the jejunum identified by small bowel capsule endoscopy in a 48 year old patient with iron deficiency anaemia. The novel motorized enteroscope could be smoothly inserted approximately 250 cm distal of the ligament of Treitz within 20 minutes. The technique allowed controlled movement of the tip of the endoscope and it provided an excellent visualization of the intubated small bowel. An angiodysplasia was detected and treated with argon plasma coagulation. Careful removal of the endoscope with counterclockwise rotation of the spiral revealed no iatrogenic mucosal trauma. No adverse events were registered.

Research paper thumbnail of 1160 Treatment of Iatrogenic Duodenal Perforation Using Over the Scope Clip

Gastrointestinal Endoscopy, 2017

A 70 year old Caucasian male with history of laparoscopic adjustable gastric banding for morbid o... more A 70 year old Caucasian male with history of laparoscopic adjustable gastric banding for morbid obesity about four years prior to admission, presented to our hospital with complaint of progressive malaise, intermittent upper abdominal pain, poor appetite, and low grade fever for past three weeks. He found to have leukocytosis. CT of the abdomen revealed significant thickening and a loculated fluid collection in the distal anterior gastric wall causing extrinsic compression of the pylorus consistent with suppurative gastritis and gastric wall abscess. He underwent esophagogastro-duodenoscopy which revealed a large partially obstructive buldge along the lesser curvature. Endoscopic ultrasound revealed a well-defined 3 to 4 cm intramural fluid collection in distal stomach. Fine needle aspiration was performed and the frankly purulent aspirate was sent for culture, gram stain, and sensitivity. After fine needle aspiration of abscess, saline was instilled into the cavity to facilitate the stent placement. Under fluoroscopic guidance, a guidewire was advanced into the cavity and a tract was created using a needle-knife. Tract was dilated with an 8 mm dilation balloon and a double pigtail stent was placed in the cavity with success. Follow up enteroscopy 5 weeks later, revealed the partially eroded adjustable gastric band into the cardia and resolution of the previously noted bulge in antrum. The pigtail stent placed during last exam was not seen in the stomach and proximal jejunum and X-Ray didn't show the stent. Patient was referred to surgery for removal of eroded adjustable gastric band. In summary, Endoscopic ultrasound guided abscess drainage is a useful treatment option for management of intra-mural gastric abscess.

Research paper thumbnail of 1035 Delayed Endoscopic Closure of a Giant Gastric Perforation

Gastrointestinal Endoscopy, 2017

Background: Small iatrogenic perforation can be treated successfully using endoscopy. However, pe... more Background: Small iatrogenic perforation can be treated successfully using endoscopy. However, perforation can be large. We describe a case of delayed endoscopic closure of giant gastric perforation using multiple over the scope clips. Case: A 72-year-old man had an upper endoscopy because of hematemesis. A bleeding large mass was found in the distal esophagus and was treated using spraying hemostasis powder. During spraying, the patient moved abruptly and developed severe abdominal distention and acute respiratory failure. An abdominal X-Ray after stabilization showed pneumoperitoneum. The patient was treated conservatively with intravenous antibiotics and nil per oral because of his other co-morbidities. Although he improved clinically, the abdominal distention persisted. Hence, a computerized tomogram was performed 3 days later, which showed a large defect in the anterior aspect of the mid stomach. He was referred for endoscopic closure and herein; we describe the technique adopted for endoscopic treatment. Endoscopic technique: First, we evacuated the pneumoperitoneum before performing endoscopy. This may prevent gastric distention and air embolism during procedure. We used Co2 insufflation to prevent recurrent pneumoperitoneum. Secondly, after assessing the morphology of the perforation, we washed it thoroughly with saline. This

Research paper thumbnail of The clinical evaluation of needle-based confocal laser endomicroscopy (nCLE) in the assessment of the pancreatic cystic lesions (PCL). A pilot study

Pancreatology, 2016

next arteries: lienalis (46), gastroduodenalis (51), hepatic (6), pancreatoduodenalis (5), left g... more next arteries: lienalis (46), gastroduodenalis (51), hepatic (6), pancreatoduodenalis (5), left gastric (2). They are manifestated as recurrent wirsungorragia or arrosive duodenal bleeding. 36 selective arterial embolisations of PA by coils were performed with definitive haemostasis (94,4%) and partial success (5,6%). All patients are survived. In other 74 cases (67,3%) we performed next open procedures: pancreatoduodenectomy (33); distal pancreatic resection with splenectomy (18), including combined gastric or colon resection (72,2%); pancreatic head resection (6), suture or PA resection (17). 3 patients (4,1%) died after open surgery. Conclusion: Interventional radiology is a successful way in treatment of intestinal bleeding due to pseudoaneuryzms after acute necritizing pancreatitis. Digestive organ's resections with their arrosive defects in one block with pancreas may be performed effectively in the specialized surgical centres with good short-term results.

Research paper thumbnail of The impact of the coronavirus disease 2019 pandemic on gastroenterologists in Southeast Asia: A mixed‐methods study

Abstract: Background and Aim: The coronavirus disease 2019 pandemic has impacted gastroenterology... more Abstract: Background and Aim: The coronavirus disease 2019 pandemic has impacted gastroenterology practices worldwide; however, its protracted effects within Southeast Asia were unknown. The primary aim of the study was to determine the impact of the pandemic on clinical demands including burnout among gastroenterologists within the region. The secondary aim was to identify risk factors for burnout and determine regional stressors. Methods: This was a mixed‐methods study. Gastroenterologists were surveyed electronically between September 1 and December 7, 2020, via gastroenterology and endoscopy societies of Brunei, Indonesia, Malaysia, Philippines, Singapore, and Thailand. Quantitative and qualitative data were collected. The 22‐item Maslach Burnout Inventory‐Human Services Survey (MBI‐HSS) was used to detect burnout. Quantitative data were non‐parametric; non‐parametric methods were used for statistical comparisons. Logistic regression was used to determine risk factors for burnou...

Research paper thumbnail of Burnout and work-related stressors in gastroenterology: a protocol for a multinational observational study in the ASEAN region

BMJ Open Gastroenterology, 2020

BackgroundClinician burnout is an important occupational hazard that may be exacerbated by the no... more BackgroundClinician burnout is an important occupational hazard that may be exacerbated by the novel COVID-19 pandemic. Within Southeast Asia, burnout in gastroenterology is understudied. The primary objective of this study is to estimate the prevalence of burnout symptoms within gastroenterology, in member states of the Associations of Southeast Asian Nations (ASEAN), during and after the COVID-19 pandemic. The secondary objective is to identify work-related stressors that contribute to burnout in ASEAN gastroenterologists.Methods and analysisThis is an observational study that will use anonymised online surveys to estimate the prevalence of burnout symptoms at two time points: during the COVID-19 pandemic in 2020 and in 2022 (assumed to be after the pandemic). Gastroenterologists from Singapore, Malaysia, Thailand, Indonesia, Philippines and Brunei will be invited to participate in the online survey through their national gastroenterology and endoscopy societies. Burnout will be a...

Research paper thumbnail of Consensus guidelines on the role of cholangioscopy to diagnose indeterminate biliary stricture

HPB, 2021

BACKGROUND Indeterminate strictures pose a therapeutic dilemma. In recent years, cholangioscopy h... more BACKGROUND Indeterminate strictures pose a therapeutic dilemma. In recent years, cholangioscopy has evolved and the availability of cholangioscopy has increased. However, the position of cholangioscopy in the diagnostic algorithm to diagnose malignancy have not been well established. We aim to develop a consensus statement regarding the clinical role of cholangioscopy in the diagnosis of indeterminate biliary strictures. METHODS The international experts reviewed the evidence and modified the statements using a three-step modified Delphi method. Each statement achieves consensus when it has at least 80% agreement. RESULTS Nine final statements were formulated. An indeterminate biliary stricture is defined as that of uncertain etiology under imaging or tissue diagnosis. When available, cholangioscopic assessment and guided biopsy during the first round of ERCP may reduce the need to perform multiple procedures. Cholangioscopy are helpful in diagnosing malignant biliary strictures by both direct visualization and targeted biopsy. The absence of disease progression for at least 6 months is supportive of non-malignant etiology. Direct per-oral cholangioscopy provides the largest accessory channel, better image definition, with image enhancement but is technically demanding. Image enhancement during cholangioscopy may increase the diagnostic sensitivity of visual impression of malignant biliary strictures. Cholangioscopic imaging characteristics including tumor vessels, papillary projection, nodular or polypoid mass, and infiltrative lesions are highly suggestive for neoplastic/malignant biliary disease. The risk of cholangioscopy related cholangitis is higher than in standard ERCP, necessitating prophylactic antibiotics and ensuring adequate biliary drainage. Per-oral cholangioscopy may not be the modality of choice in the evaluation of distal biliary strictures due to inherent technical difficulties. CONCLUSION Evidence supports that cholangioscopy has an adjunct role to abdominal imaging and ERCP tissue acquisition in order to evaluate and diagnose indeterminate biliary strictures.