Song, Louis Wong Kee

AbstractObjectiveTo compare reflux symptoms, Zenker's diverticulum recurrence, and clinical outcomes in patients with and without a history of hiatal hernia who underwent Zenker's diverticulotomy (ZD).Study DesignSingle institution retrospective review.SettingTertiary care academic hospital.MethodsA retrospective review of patients with and without a history of hiatal hernia who underwent ZD via an open stapler, rigid endoscopic CO2 laser, stapler, or harmonic scalpel technique from January 2006 to December 2020 was performed. Data were abstracted for patient demographics, reflux symptoms, and rates of adverse events and symptomatic recurrence.ResultsA total of 426 patients were included in the study, 97 (22.8%) of which had a history of hiatal hernia. Eleven patients (11.3%) with a history of hiatal hernia had undergone Nissen fundoplication prior to ZD. Patients with a history of hiatal hernia showed less symptomatic improvement postoperatively. Significant differences were noted in the change in the Eating Assessment Tool (EAT‐10) (P < .01) and Reflux Symptom Index (RSI) (P = .03) where patients without a history of hiatal hernia improved more than hiatal hernia patients. Despite these differences in symptom relief, rates of postoperative complications and rates of recurrence did not significantly differ between groups. The median time to recurrence was similar for both groups.ConclusionPatients without a history of hiatal hernia had significantly larger improvements in EAT‐10 and RSI scores compared to patients with a history of hiatal hernia. However, these differences in scores may not represent clinically meaningful differences. There were no significant differences in postoperative adverse events or in recurrence of the Zenker's diverticulum between groups.

Abstract Background and aims Benign gastrointestinal (GI) strictures are often refractory to standard endoscopic interventions. Fully covered coaxial lumen-apposing metal stents (LAMS) have emerged as a novel therapy for these strictures. The aim of this study was to evaluate the safety and efficacy of LAMS for refractory GI strictures. Patients and methods A retrospective analysis was performed for patients who underwent LAMS placement for benign luminal strictures in three US centers between January 2014 and December 2016. The primary outcomes were technical success and initial clinical success of LAMS placement. Secondary outcomes were stent migration, rate of re-intervention, and adverse events. Results A total of 49 patients underwent 56 LAMS placement procedures. Previous treatment had failed in 39 patients (79.6 %), and anastomotic strictures were the indication in 77.6 % (38/49), with the most common site being gastrojejunal (34.7 % [17/49]). Technical success was achieved in all procedures and initial clinical success was achieved in 96.4 % of all procedures (54/56). Patient initial clinical success was 95.9 % (47/49). Stent migration occurred in 17.9 % of procedures, and was more likely to occur at sites in the lower GI tract (P = 0.02). The mean stent dwell time was 100.6 days, and the mean follow-up was 169.8 days. Minor adverse events, not requiring hospitalization, occurred in 33.9 % of procedures, including subsequent stricture progression (10.7 %). In cases where LAMS were removed, mean follow-up time was 102.2 days. The re-intervention rate was 75 % at 300 days follow-up after stent removal. Of the LAMS placed at anastomotic strictures, 36.4 % required re-intervention, with approximately two-thirds of these re-interventions requiring placement of a new stent or surgery. Conclusion LAMS placement was successful for the management of refractory GI strictures, with good technical and initial clinical success rates. However, re-intervention rates after LAMS removal were high, and many strictures were not resolved by an extended period of stenting with these coaxial stents. LAMS placement offers additional therapeutic options and in selected cases might be considered a destination therapy for patients with recalcitrant benign strictures.

Esophageal varices are a significant complication of portal hypertension. Endoscopic variceal ligation (EVL) is one of the clinical standards for treating these varices and preventing their hemorrhage. Limitations of EVL include the risk of stricture formation and postband ulcer bleeding due to the damage caused to the esophageal mucosa, as well as the need for multiple endoscopic treatment sessions to eradicate the varices. The goal of this study is to develop a device and evaluate the technical feasibility of microwave ablation to seal esophageal varices, while preventing thermal damage to the surface mucosal tissue. A microwave applicator with a directional radiation pattern was developed for endoscopic ablation of esophageal varices. Electromagnetic and bioheat transfer computational models were employed to optimize the design of the microwave applicator and evaluate energy delivery strategies for this application. Experiments in ex vivo and in vivo tissue were employed to verify simulation results. Simulations predicted enhanced heating performance of the antenna using an angled monopole radiating element. Further, simulations indicate that while the endoscopic cap attenuated electric fields in tissue, it also enhanced surface cooling of tissue, increasing the likelihood of preserving mucosal tissue. Experiments in ex vivo tissue indicated the feasibility of sealing veins with 77 W microwave power delivered for 30 s. In vivo experiments demonstrated the ability to seal veins, while preserving surface tissue. This study demonstrated the technical feasibility of microwave thermal ablation for treating esophageal varices using a 2.45 GHz water-cooled directional microwave applicator.