Christopher J Gostout

Mayo Clinic - Rochester, Rochester, Minnesota, United States

Are you Christopher J Gostout?

Claim your profile

Publications (310)1374.01 Total impact

  • Kohei Takizawa, Mary A. Knipschield, Christopher J. Gostout
    Gastrointestinal Endoscopy. 11/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: The field of bariatric surgery has been rapidly growing and evolving over the past several decades. During the period that obesity has become a worldwide epidemic, new interventions have been developed to combat this complex disorder. The development of new laparoscopic and minimally invasive treatments for medically-complicated obesity has made it essential that gastrointestinal physicians obtain a thorough understanding of past developments and possible future directions in bariatrics. New laparoscopic advancements provide patients and practitioners with a variety of options that have an improved safety profile and better efficacy without open, invasive surgery. The mechanisms of weight loss after bariatric surgery are complex and may in part be related to altered release of regulatory peptide hormones from the gut. Endoscopic techniques designed to mimic the effects of bariatric surgery and endolumenal interventions performed entirely through the gastrointestinal tract offer potential advantages. Several of these new techniques have demonstrated promising, preliminary results. We outline herein historical and current trends in the development of bariatric surgery and its transition to safer and more minimally invasive procedures designed to induce weight loss.
    World journal of gastroenterology : WJG. 10/2014; 20(37):13424-13445.
  • [Show abstract] [Hide abstract]
    ABSTRACT: A subset of patients with non-variceal gastrointestinal bleeding fail, or are unsuitable candidates for, endoscopic, radiologic, and surgical interventions. Endoscopic ultrasound (EUS)-guided intervention might be effective in these patients. We performed EUS-guided hemostatic interventions for 17 patients with non-variceal gastrointestinal bleeding from June 2003 through May 2014 who failed, or were unsuitable candidates for, additional therapies. Indications for treatment included gastrointestinal stromal tumors, colorectal vascular malformations, duodenal masses or polyps, Dieulafoy lesions, duodenal ulcers, rectally invasive prostate cancer, pancreatic pseudoaneurysms, ulcerated esophageal cancer, and ulceration following Roux-en-Y gastric bypass. Following the procedure, 88% of patients have had no further bleeding related to the treated lesion, over a median follow-up period of 12 months. EUS-guided hemostatic therapy is therefore feasible and useful for select patients with clinically severe, refractory, or recurrent non-variceal gastrointestinal bleeding.
    Clinical Gastroenterology and Hepatology. 09/2014;
  • Surgical endoscopy. 06/2014;
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Data comparing operative and endoscopic resection of adenomas of the ampulla of Vater are limited. Our aims were to evaluate and compare the long-term results and outcomes of endoscopic and operative resections of benign tumors of the ampulla of Vater as well as to determine which features of benign periampullary neoplasms would predict recurrence or failure of endoscopic therapy and therefore need for operative treatment.
    Journal of gastrointestinal surgery : official journal of the Society for Surgery of the Alimentary Tract. 06/2014;
  • Kazuki Sumiyama, Christopher J Gostout, Hisao Tajiri
    [Show abstract] [Hide abstract]
    ABSTRACT: Submucosal endoscopy with a mucosal flap (SEMF) safety valve technique is a global concept in which the submucosa is a free working space for endoscopic interventions. A purposefully created intramural space provides an endoscopic access route to the deeper layers and into the extraluminal cavities. The mucosa overlying the intramural space is protective, reducing contamination during natural orifice transluminal endoscopic surgery (NOTES) procedures and providing a sealant flap to repair the entry point and the submucosal space. In addition to NOTES, SEMF enables endoscopic achalasia myotomy, histologic analysis of the muscularis propria, and submucosal tumor removal.
    Gastrointestinal endoscopy clinics of North America 04/2014; 24(2):265-272.
  • Nabeel Azeem, Christopher J Gostout, Mary Knipschield, Todd H Baron
    [Show abstract] [Hide abstract]
    ABSTRACT: Patients with primary sclerosing cholangitis (PSC) have an increased lifetime risk of cholangiocarcinoma (CCA). Detection of localized CCA in patients with PSC may result in curative liver transplantation. Recently, high-resolution per-oral video cholangioscopy (PVCS) has become available and may be useful for evaluating for biliary dysplasia. Narrow-band imaging (NBI) has shown promising results in detecting dysplasia in the esophagus and colon, but its utility in the bile duct is unproven. Evaluate NBI video PVCS in screening for dysplasia in patients with PSC. Prospective case series. Tertiary-care referral center. Patients with PSC undergoing ERCP between December 2008 and July 2010. ERCP with white-light and NBI PVCS and biopsy of suspicious lesions. Dysplasia detection. A total of 30 patients were enrolled. Median follow-up was 319.5 days. Four patients had a final diagnosis of CCA (2 extrahepatic, 2 intrahepatic). NBI visualized the 2 extrahepatic CCAs and allowed determination of tumor margins. The bile duct mucosa by NBI visual appearance in patients with PSC was variable. No correlation with CCA development could be determined. There was a 48% increase in suspicious lesions biopsied with NBI compared with white-light imaging, although NBI-directed biopsies did not improve the dysplasia detection rate. Small sample size, single center, referral bias. NBI allowed visualization of tumor margins in CCA as compared with traditional fluoroscopy-based ERCP. An improvement in dysplasia detection in patients with PSC could not be demonstrated despite an increase in the biopsy rate. Additional experience is needed to assess the utility of NBI in screening for CCA in patients with PSC. (Clinical trial registration number: NCT00951327.).
    Gastrointestinal endoscopy 10/2013; · 6.71 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Staging peritoneoscopy is typically done by laparoscopy in the operating room. Natural orifice transluminal endoscopic surgery peritoneoscopy is an appealing alternative to the current approach. Transcolonic submucosal endoscopy with mucosal flap (SEMF) may provide natural orifice transluminal endoscopic surgery peritoneoscopy. The aim was to verify the feasibility and safety of transcolonic peritoneoscopy with SEMF (TCPS) in a porcine survival model. Survival study. Animal research unit. Seven target beads were placed in the peritoneal cavity by laparoscopy in each of 6 animals, and TCPS was performed to identify and touch beads to simulate biopsy. Animals were euthanized after 1 week, at which time, laparotomy was performed and the SEMF site was resected for histological analysis. The number of beads identified and touched during peritoneoscopy, rate of successful completion of TCPS, procedure time, mortality equivalent 1 week after TCPS, adverse event rate, histological assessment of SEMF site. All 7 beads in all 6 pigs were identified and touched during TCPS. The success rate of TCP was 100%. No major adverse events occurred during the procedure. The median procedure times for the creation of a submucosal tunnel, peritoneoscopy, closure of mucosal incision, and entire procedure were 19.5, 17, 9.5, and 45 minutes, respectively. All pigs survived until euthanasia, and there was no evidence of peritonitis or severe infection. Animal study, single endoscopist, small sample size. Results of this study indicate that TCPS is feasible and safe in a porcine survival model.
    Gastrointestinal endoscopy 08/2013; · 6.71 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Minimum training for capsule endoscopy (CE) is based on societal guidelines and expert opinion. Objective measures of competence are lacking. Our objectives were to (1) establish structured CE training curriculum during a gastroenterology fellowship, (2) develop a formalized assessment tool to evaluate CE competency, (3) prospectively analyze trainee CE competency, (4) define metrics for trainee CE competence by using comparative data from CE staff, and (5) determine the correlation between CE competence and previous endoscopy experience. Single-center, prospective analysis over 6 years. Tertiary academic center. Gastroenterology fellows and CE staff. Structured CE training was implemented with supervised CE interpretation. Capsule Competency Test (CapCT) was developed and data collected on the number of CEs, upper endoscopies, colonoscopies, and push enteroscopies performed. Trainee competence defined as CapCT score 90% or higher of the mean staff score. A total of 39 fellows completed CE training and CapCT. Fellows were grouped according to number of completed CE interpretations: 10 or fewer (n = 13), 11 to 20 (n = 19), and 21 to 35 (n = 7). Eight CE staff completed CapCT with a mean score of 91%. Mean scores for trainees with fewer than 10, 11 to 20, and 21 to 35 CE interpretations were 79%, 79%, and 85%, respectively. A significant difference was seen between staff and fellow scores with 10 or fewer and 11 to 20 interpretations (P < .001). No correlation was found between trainee scores and previous endoscopy experience. Single center. Using a structured CE training curriculum, we defined competency in CE interpretation by using the CapCT. Based on these findings, trainees should complete more than 20 CE studies before assessing competence, regardless of previous endoscopy experience.
    Gastrointestinal endoscopy 07/2013; · 6.71 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: EUS can provide access to the main pancreatic duct (MPD) for therapeutic intervention. The long-term clinical success of EUS-guided MPD interventions is unknown. To determine technical and clinical success rates, predictors of success, and long-term outcomes of EUS-guided MPD intervention. Retrospective, single-center study. Tertiary-care referral center. Forty-five patients. EUS-guided MPD stent retrieval or placement. Technical and clinical success rates, adverse events, and long-term clinical outcomes. Among the 45 patients, 37 had undergone failed ERCP, and 29 had surgically altered anatomy. Median follow-up after initial EUS-guided intervention was 23 months. Two patients underwent EUS for stent removal, and EUS-guided MPD stent placement was attempted in 43 patients. Technical success was achieved in 32 of 43 patients (74%) with antegrade (n = 18) or retrograde (n = 14) stent insertion. Serious adverse events occurred in 3 patients (6%). Patients underwent a median of 2 (range 1-6) follow-up procedures for revision or removal of stents, without adverse events. Complete symptom resolution occurred in 24 of 29 patients (83%) while stents were in place, including all 6 with nondilated ducts. Stents were removed in 23 patients, who were then followed for an additional median of 32 months; 4 patients had recurrent symptoms. Among the 11 failed cases, most had persistent symptoms or required surgery. Retrospective study design, individualized patient management. EUS-guided MPD intervention is feasible and safe, with long-term clinical success in the majority of patients. EUS provides important treatment options, particularly in patients who would otherwise undergo surgery.
    Gastrointestinal endoscopy 07/2013; · 6.71 Impact Factor
  • Source
    Gastrointestinal endoscopy 07/2013; · 6.71 Impact Factor
  • Kohei Takizawa, Mary A Knipschield, Christopher J Gostout
    [Show abstract] [Hide abstract]
    ABSTRACT: We developed a technique, submucosal endoscopy with mucosal resection (SEMR) intended to make endoscopic submucosal dissection easier and safer. With this technique, the submucosal layer is balloon dissected in lieu of electrosurgical knife dissection. The aim of this study was to further evaluate SEMR in the porcine rectum and colon. Targeted sites in the rectum and the distal colon were marked by spot coagulation. Submucosal fluid cushions (SFC) were created followed by a circumferential mucosal incision. After isolation of the targeted mucosa, balloon dissection was initiated. The balloon catheter was inserted deep into SFC and the inflated balloon repeatedly pulled back toward the endoscope tip to disrupt the submucosa. Residual strands of submucosa were cut. Dissection difficulty scores (DDS) were used using a visual analogue scale ranging from 0 to 5 (failed). The entire study period was divided into three periods (first period, pigs 1-10; second period, pigs 11-20; third period, pigs 21-30). Sixty lesions in 30 pigs were resected using SEMR. The en block resection rate was 95 %. There were three incomplete resections, two as a result of an errant site location and one as a result of a floppy prototype balloon catheter tip. The median resected size, procedure time, and DDS were 6.0 cm, 25 min, and 1. All three failed cases occurred in first period. The procedure time in third period was significantly shorter than the second period (P = 0.0017). The DDS in first period was significantly higher than the second (P = 0.0024) and third (P = 0.0155) periods. Two perforations, one muscularis propria catheter perforation, and one mucosal perforation were observed (3.3 %). Large mucosal target sites in the rectum and distal colon could be safely removed en bloc by means of a hybrid technique, SEMR, with blunt submucosal balloon dissection.
    Surgical Endoscopy 07/2013; · 3.43 Impact Factor
  • Christopher J. Gostout
    [Show abstract] [Hide abstract]
    ABSTRACT: Submucosal endoscopy with saftey valve mucosal flap was developed in the animal laboratory of the Mayo Clinic Developmental Endoscopy Unit. This concept, and ultimately clinical technique, was an outgrowth of earlier efforts to improve endoscopic excision of mucosal disease by manipulating the submucosa. The ability of the mucosa to readily separate from the submucosa (delaminate) was the critical observation that was refined into a method transforming the submucosa into a working space while allowing the overlying mucosal flap to serve as a protective barrier.
    Techniques in Gastrointestinal Endoscopy 07/2013; 15(3):127–130.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background and study aims: Removal of a lesion containing an ulcer scar is one of the most challenging applications of endoscopic submucosal dissection (ESD). The present study examined whether a novel balloon dissector could cleave fibrotic submucosal tissue beneath ulcer scars.Methods: Six pigs were studied. Endoscopic mucosal resection (EMR) with ligation was performed at 7 or 8 sites in the stomach for each animal; 4 weeks later, 23 sites with a visible scar were selected for submucosal dissection. The procedure involved first creating a submucosal fluid cushion (SFC) by injecting either saline mixed with mesna or pure saline. A slender, compliant balloon with a diameter of 8, 13, or 18 mm was inserted into the SFC. The balloon was unfolded and thrust forward to cleave the fibrotic submucosa over approximately 5 cm.Results: Fibrotic submucosa was dissected within 90 seconds in 17 of 23 attempts. Isolating the ulcer scar from the muscularis with the SFC prior to balloon dissection and using a thinner balloon catheter both ensured a better dissection.Conclusions: The fibrotic submucosa underlying post-EMR scars can be dissected with the novel balloon dissector, although the technique is less effective in cases with no sign of lifting.
    Endoscopy 06/2013; · 5.74 Impact Factor
  • Barham K Abu Dayyeh, Elizabeth Rajan, Christopher J Gostout
    [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND: Obesity and its associated conditions, including type 2 diabetes and cardiovascular disease, have reached epidemic proportions. High-efficacy, high-risk surgical approaches are unlikely to meet the increasing burden of disease. Emerging endoscopic technologies have opened the door for endoscopic approaches to reproduce many of the benefits of GI weight loss surgery and thereby contribute to the effective treatment of obesity and its associated disorders. OBJECTIVE: To demonstrate the technical feasibility of transoral endoscopic gastric volume reduction with an endoscopic suturing device in a fashion similar to sleeve gastrectomy for the treatment of obesity. DESIGN: Single-center, pilot feasibility study. PATIENTS: Four human subjects with obesity. INTERVENTIONS: Transoral sleeve gastroplasty. MAIN OUTCOME MEASUREMENTS: Technical feasibility. RESULTS: We successfully used an endoscopic free-hand suturing system in 4 subjects, thus demonstrating the technical feasibility of a novel technique to mimic the anatomic manipulations created by surgical sleeve gastrectomy endoscopically. LIMITATIONS: Pilot feasibility study with small number of subjects. CONCLUSIONS: Endoscopic sleeve gastroplasty for treatment of obesity is feasible.
    Gastrointestinal endoscopy 05/2013; · 6.71 Impact Factor
  • Gastrointestinal endoscopy 02/2013; · 6.71 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND: Endoscopic retrograde cholangiography (ERC) is technically challenging in liver transplant patients with Roux-en-Y biliary anastomosis. The optimal endoscope for such cases remains unknown. OBJECTIVE: Compare efficacy and safety of performing ERC in liver transplant patients with Roux-en-Y biliary anastomosis by using an adult colonoscope (AC), a pediatric colonoscope (PC), and a single-balloon enteroscope (SBE). DESIGN: Retrospective chart review. SETTING: Tertiary-care referral center. PATIENTS: Liver transplant patients with Roux-en-Y biliary anastomoses. INTERVENTION: ERC with AC, PC, and SBE. MAIN OUTCOME MEASUREMENTS: Rates of reaching the afferent limb and biliary anastomosis; rates of cannulation; rates of diagnostic, therapeutic, and procedural success; and number of adverse events. RESULTS: Ninety patients underwent 199 ERCs from 2002 to 2012; 86 with an AC, 55 with a PC, and 58 with an SBE. Biliary cannulation and diagnostic, therapeutic, and procedural success rates were all significantly higher with an SBE than with a PC. Among patients undergoing the initial ERC, no statistical difference was found among SBE, the PC, and an AC. However, the rate of procedural success with SBE during initial ERC over the last 4 years has increased. Of 25 total failures with ACs, exchange for SBEs resulted in procedural success in 4 of 4 attempts. Of 22 failures with a PC, exchange for an SBE resulted in success in 3 of 4 cases. Of 4 failures with SBE exchange in 6 cases (4 to AC, 2 to PC), SBE resulted in success in only 1. No adverse events occurred directly related to type of endoscope. LIMITATIONS: Retrospective study, single center, lack of standardized approach to selection of endoscopes, uncontrolled variables (general anesthesia, learning curve). CONCLUSION: In liver transplant patients with Roux-en-Y anatomy, rates of biliary cannulation, therapeutic success, and procedural success are higher with use of an SBE than with a PC and tend to be higher compared with use of an AC among the overall cohort. Use of an SBE and procedural success rates with SBEs have increased over the last 4 years. Failed cases with either an AC or PC can be completed if exchanged for an SBE.
    Gastrointestinal endoscopy 01/2013; · 6.71 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND: Ulcer perforation carries up to a 30 % 1-year mortality rate. Intervention-related adverse events are among statistically significant predictors of 1-year mortality. A natural orifice transluminal endoscopic surgical (NOTES) approach may be less invasive and may decrease procedure-related adverse events by diminishing the so-called second hit, thus leading to decreased morbidity and mortality. We sought to assess the feasibility of an endoscopic transluminal omental plug technique in patients with perforated gastroduodenal ulcers under laparoscopic guidance. METHODS: Patients with suspected acute gastroduodenal ulcer perforations were offered participation in this prospective pilot study. Closure of the perforation was attempted using the NOTES omental plug technique. Demographic, clinical, endoscopic, and radiographic data were abstracted, as were data for morbidity, mortality, and pilot data regarding quality of life (QOL). RESULTS: From February 2010 through February 2012, a total of 17 patients presented to a tertiary care center with clinically suspected perforated ulcer. Of seven patients (mean age 79 years, range 64-89 years) who consented to the study, three underwent the study procedure. All patients had multiple comorbidities. Two patients presented with 4-6 mm perforated peptic ulcers and underwent successful laparoscopic-assisted NOTES omental and falciform ligament patch closure, respectively. Postoperative radiographic contrast studies showed no leak, and patients were discharged home on postoperative days 3 and 4. The third patient had undergone enterocutaneous fistula repair with herniorrhaphy 6 weeks before. Although a transluminal endoscopic approach was feasible, the omentum was under too much tension to be secured. This procedure was converted to an open omental patch repair. For all but one patient who provided consent, obtaining QOL data was feasible. CONCLUSIONS: Initial results from a laparoscopic-assisted NOTES approach for closure of perforated peptic ulcers appear promising and enable swift recovery in selected patients. This is especially important in elderly and/or immunocompromised patients. Technical details and patient selection criteria continue to evolve.
    Surgical Endoscopy 01/2013; · 3.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Endoscopic perforations are surgically repaired by using an omentum patch. Omentum substitutes may have broader applications particularly in certain sites (eg, esophagus). Evaluate a self-expandable foam matrix plug as a synthetic omentum substitute for repairing iatrogenic gastric perforations in a 4-week survival pig model. Experimental pilot study. Laboratory. A laparoscopic plug repair of a 1-cm, full-thickness, gastric perforation was carried out by using either a polyurethane foam matrix plug (FMP, 8 animals) or an omentum plug (OP, 6 animals, control group). Follow-up endoscopy was carried out at 1 and 4 weeks. At necropsy, the perforation site was evaluated for adhesions and histology by using hematoxylin and eosin analysis. A portion of the implant was sent for bacterial and fungal culture. All procedures were technically simple and successful. Thirteen animals thrived well for 4 weeks. One animal from the FMP group died 3 days postoperatively from diffuse peritonitis because of a misplaced plug. All remaining FMPs were intact at 4 weeks and colonized with mixed bacteria, except one animal presenting with FMP migration after 1 week. Histologically, the FMP group had more prominent inflammation and suppuration as compared with the OP group, all limited to its adjacent tissue. Animal study. The FMP offered a technically simple and feasible option for repairing iatrogenic gastric perforations. With effective sealing, the clinical outcome is similar to that of an omentum patch repair. Migration and inadequate sealing is a concern, which can lead to peritonitis and sepsis. Further development is needed to improve FMP performance.
    Gastrointestinal endoscopy 01/2013; 77(1):123-30. · 6.71 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The pathogenesis of several common gastric motility diseases and functional GI disorders remains essentially unexplained. Gastric wall biopsies that include the muscularis propria to evaluate the enteric nervous system, interstitial cells of Cajal, and immune cells can provide important insights for our understanding of the etiology of these disorders. To determine the technical feasibility, reproducibility, and safety of performing a full-thickness gastric biopsy (FTGB) by using a submucosal endoscopy with mucosal flap (SEMF) technique; the technical feasibility, reproducibility, and safety of tissue closure by using an endoscopic suturing device; the ability to identify myenteric ganglia in resected specimens; and the long-term safety. Single center, preclinical survival study. Animal research laboratory, developmental endoscopy unit. Twelve domestic pigs. Animals underwent an SEMF procedure with gastric muscularis propria resection. The resultant offset mucosal entry site was closed by using an endoscopic suturing device. Animals were kept alive for 2 weeks. The technical feasibility, reproducibility, and safety of the procedure; the clinical course of the animals; the histological and immunochemical evaluation of the resected specimen to determine whether myenteric ganglia were present in the sample. FTGB was performed by using the SEMF technique in all 12 animals. The offset mucosal entry site was successfully closed by using the suturing device in all animals. The mean resected tissue specimen size was 11 mm. Mean total procedure time was 61 minutes with 2 to 4 interrupted sutures placed per animal. Histology showed muscularis propria and serosa, confirming full-thickness resections in all animals. Myenteric ganglia were visualized in 11 of 12 animals. The clinical course was uneventful. Repeat endoscopy and necropsy at 2 weeks showed absence of ulceration at both the mucosal entry sites and overlying the more distal muscularis propria resection sites. There was complete healing of the serosa in all animals with minimal single-band adhesions in 5 of 12 animals. Retained sutures were present in 10 of 12 animals. Animal experiment. FTGB by using the SEMF technique and an endoscopic suturing device is technically feasible, reproducible, and safe. Larger tissue specimens will allow improved analysis of multiple cell types.
    Gastrointestinal endoscopy 11/2012; 76(5):1014-9. · 6.71 Impact Factor

Publication Stats

6k Citations
1,374.01 Total Impact Points

Institutions

  • 1989–2014
    • Mayo Clinic - Rochester
      • • Department of Gastroenterology and Hepatology
      • • Department of Gastroenterologic & General Surgery
      • • Department of Hospital Internal Medicine
      Rochester, Minnesota, United States
  • 2013
    • Shizuoka Cancer Center
      Sizuoka, Shizuoka, Japan
  • 1987–2013
    • Mayo Foundation for Medical Education and Research
      • • Department of Surgery
      • • Division of General Surgery
      • • Division of Gastroenterology and Hepatology
      • • Division of Pulmonary and Critical Care Medicine
      • • Mayo Medical School
      Jacksonville, FL, United States
  • 2005–2012
    • Johns Hopkins Medicine
      • Department of Medicine
      Baltimore, MD, United States
  • 2008–2011
    • The Jikei University School of Medicine
      • Department of Endoscopy
      Tokyo, Tokyo-to, Japan
    • Cathay General Hospital
      T’ai-pei, Taipei, Taiwan
  • 2009
    • Dartmouth–Hitchcock Medical Center
      Lebanon, New Hampshire, United States
  • 2004–2008
    • Beth Israel Deaconess Medical Center
      • • Division of Gastroenterology
      • • Department of Medicine
      Boston, Massachusetts, United States
    • Medical University of South Carolina
      • Digestive Disease Center
      Charleston, SC, United States
  • 1993–2008
    • University of Minnesota Rochester
      Rochester, Minnesota, United States
  • 2007
    • Second Military Medical University, Shanghai
      Shanghai, Shanghai Shi, China
    • University of Texas Medical Branch at Galveston
      Galveston, Texas, United States
    • Taichung Veterans General Hospital
      臺中市, Taiwan, Taiwan
  • 2005–2007
    • Johns Hopkins University
      • Division of Gastroenterology
      Baltimore, MD, United States