Jun-Hyung Cho

Peroral Endoscopic Myotomy for Treatment of Achalasia: Initial Results of a Korean Study

Background/Aims Achalasia is a rare esophageal motility disorder. Recently, a novel endoscopic technique, peroral endoscopic myotomy (POEM), was introduced as an alternative treatment for achalasia. We report the results and short term outcomes of POEM for patients with achalasia. Methods POEM was performed in 13 patients with achalasia. The procedure consisted of creating a submucosal tunnel followed by endoscopic myotomy of circular muscle bundles. The mucosal entry was closed by conventional hemostatic clips. A validated clinical symptom score (Eckardt score) and high resolution manometry were used to evaluate the outcomes. Results Both the clinical score of achalasia, as well as the resting lower esophageal sphincter (LES) pressure, were significantly reduced after POEM. Mean posttreatment Eckardt score was 0.4±0.7, compared to 6.4±1.9 prior to the treatment (p=0.001). The mean pretreatment and posttreatment LES pressure was 30.3 and 15.3 mm Hg, respectively (p=0.007). Following POEM, symptomatic relief from dysphagia without reflux symptoms was observed in all patients (13/13). No serious complications related to POEM were encountered. Conclusions Based upon our initial experience, the authors believe that POEM is a feasible, safe, and effective treatment and may possibly substitute established treatments of refractory achalasia.

Hybrid natural orifice transluminal endoscopic surgery: endoscopic full-thickness resection of early gastric cancer and laparoscopic regional lymph node dissection--14 human cases.

BACKGROUND AND STUDY AIM Minimally invasive treatment has become a mainstay management strategy for early gastric cancer (EGC). Full-thickness incision of the gastric wall using natural orifice transluminal endoscopic surgery (NOTES) has been reported but is not easily applicable in clinical settings at present. The aim of the current study was to assess the feasibility of hybrid NOTES, which consists of endoscopic full-thickness gastric resection and a laparoscopic lymphadenectomy. PATIENTS AND METHODS This was a prospective, pilot study at a single tertiary care referral center. A total of 14 patients with EGC located above the lower third of the stomach underwent hybrid NOTES. Clinically, the patients had contraindications to exclusive treatment using endoscopic submucosal dissection (ESD). The main outcome measure was technical success of hybrid NOTES. RESULTS All cases were resected en bloc with negative surgical margins. Histologically, four cases were mucosal cancers, and 10 cases were submucosal cancers. The median tumor size was 26 mm (range 12 - 90 mm). Lymphatic vessel invasion was found in four cases without lymph node metastasis (LNM). The median number of obtained lymph nodes was 18 (range 7 - 67). LNM was discovered in one case of undifferentiated submucosal cancer without lymphovascular invasion. Hybrid NOTES was conducted without intraoperative or postoperative adverse events in nine cases. The median operating time and estimated blood loss of successful cases were 143 minutes (range 110 - 253 minutes) and 16 mL (range 5 - 30 mL), respectively. The median hospital stay was 6 days (range 4 - 10 days). Five cases were converted to a subtotal gastrectomy for various reasons. CONCLUSIONS Hybrid NOTES could be a bridge between endoscopic resection and laparoscopic surgery and may prevent extensive gastrectomy in patients with EGC.

Effect of drug-eluting metal stents in benign esophageal stricture: an in vivo animal study.

BACKGROUND AND STUDY AIMS The aim of this study in canines was to investigate the effectiveness and safety of self-expandable metal stents, which were coated with paclitaxel to minimize the tissue response. MATERIALS AND METHODS 14 dogs (5-10 kg) were randomly allocated to two groups. Drug-eluting stents (DES, n = 7) or nondrug-eluting stents (non-DES, n = 7) were endoscopically inserted and fixed in the esophagus of healthy dogs. Every 2 weeks, for a maximum period of 8 weeks, an endoscopic examination was performed to evaluate the status of stent insertion, the grade of tissue hyperplasia, and mucosal change at both ends of the stent. RESULTS One case of stent migration was observed after 4 weeks in the non-DES group. In this group, tissue reaction and hyperplasia remained for more than 4 weeks after stent insertion. By contrast, an endoscopic examination of the surrounding esophageal mucosa in the DES group showed very little tissue reaction, and the stent was easily separated from the esophageal tissue. CONCLUSION Although further studies are required to confirm our results, we suggest that these newly designed DES may provide an alternative tool to manage refractory benign esophageal stricture.

The accuracy of probe-based confocal endomicroscopy versus conventional endoscopic biopsies for the diagnosis of superficial gastric neoplasia (with videos).

BACKGROUND Probe-based confocal laser endomicroscopy (pCLE) allows real-time in vivo histologic evaluation of GI mucosal lesions. Although pCLE has been used for various GI disorders, the significance of pCLE for gastric lesions is largely unknown. OBJECTIVE We compared the accuracy of conventional endoscopic forceps biopsy and pCLE for the diagnosis of superficial gastric neoplasia before endoscopic resection. DESIGN Prospective comparative study. SETTING Single tertiary referral center. PATIENTS This study involved 54 superficial gastric neoplasias in 46 patients. MAIN OUTCOME MEASUREMENT Accuracy of in vivo and offline pCLE diagnosis and interobserver agreement. METHODS pCLE was performed before endoscopic resection of superficial gastric neoplasias previously diagnosed by endoscopic biopsy. The overall accuracy of endoscopic, in vivo pCLE, and offline pCLE diagnosis was compared with postendoscopic resection histopathology. RESULTS Endoscopic resection was performed on 54 lesions. On final histopathology, there were 3 non-neoplastic lesions, 19 gastric dysplasias, 22 differentiated adenocarcinomas, and 10 undifferentiated adenocarcinomas. The overall agreement with the final histopathology was substantial for conventional biopsies (κ = 0.617) and excellent for in vivo pCLE (κ = 0.824) (P < .001). The overall accuracy for the diagnosis of adenocarcinoma was 91.7% for pCLE and 85.2% for conventional biopsies (P = .065). The combined accuracy of conventional endoscopic biopsies and pCLE was 98.1%. The interobserver agreement for offline pCLE diagnosis was excellent (κ = 0.931). LIMITATIONS Single-center study, small sample size. CONCLUSION Our study showed that pCLE can provide an accurate diagnosis for superficial gastric neoplasia. pCLE has the potential to compensate for the inherent limitations of a conventional endoscopic biopsy.

Endoscopic submucosal dissection with sentinel node navigation surgery for early gastric cancer.

We combined endoscopic submucosal dissection (ESD) and sentinel node navigation surgery with the purpose of achieving complete resection of early gastric cancer while preserving the organ and assessing pathological nodal status. A total of 13 patients with cT1( ≤ 3 cm)N0 early gastric cancer underwent combined ESD and sentinel node navigation surgery (ESN) at a single tertiary referral center. Sentinel node navigation surgery using indocyanine green was performed during ESD and all suspected sentinel nodes were removed laparoscopically and examined intraoperatively. ESN was converted to gastrectomy with D2 dissection if there was evidence of metastasis on frozen section. ESN was completed in 12 patients and in 1 patient was converted to gastrectomy after sentinel node navigation surgery. En bloc tumor resection was achieved in all cases. Two patients underwent additional gastrectomy because they had tumor-positive vertical margins. In all cases ESN was conducted without intraoperative or postoperative adverse events. ESN is a feasible minimally invasive procedure that allows en bloc tumor resection to be achieved while assessing the pathological status of the lymph nodes.

Double-Balloon Enteroscopy in Elderly Patients: Is It Safe and Useful?

Background/Aims Providers may be hesitant to perform double-balloon enteroscopy (DBE) in the elderly because the increased number of co-morbidities in this population poses a greater risk of complications resulting from sedation. There are limited data on the use of DBE in the elderly. Here, we assessed the safety and efficacy of DBE in the elderly compared to those in younger patients. Methods We retrospectively analyzed the medical records of 158 patients who underwent 218 DBEs. Patients were divided into an elderly group (age ≥65 years; mean 71.4±5.4; n=34; 41 DBEs) and a younger group (age <65 years; mean 39.5±13.5; n=124; 177 DBEs). Results In both groups, the most common indication for DBE was obscure gastrointestinal bleeding. Mucosal lesions (33.3% vs. 60.9%; P=0.002) were the most common finding in both groups, followed by tumors (30.8% vs. 14.1%; P=0.036). The elderly were more likely to receive interventional therapy (51.3% vs. 23.5%; P=0.001). The diagnostic yield of DBE was slightly higher in the elderly group (92.3% vs. 86.5%; P=0.422), but was not statistically significant. The therapeutic success rate of DBE was 100% in the elderly group compared to 87.5% in the younger group (P=0.536). The overall DBE complication rate was 1.8% overall, and this rate did not differ significantly between the groups (2.6% vs. 1.7%; P=0.548). Conclusions DBE is safe and effective in the elderly, and has a high diagnostic yield and high therapeutic success rate.

High-resolution impedance manometry facilitates assessment of pharyngeal residue and oropharyngeal dysphagic mechanisms

The utility of high-resolution impedance manometry (HRIM) for evaluating oropharyngeal dysphagia (OPD) has been investigated. These approaches are limited because of the sophisticated methodology. A method of transforming HRIM into a simple and useful diagnostic tool for evaluating OPD is needed. A videofluoroscopic swallowing study (VFSS) and HRIM were performed by independent blinded examiners in 26 consecutive healthy volunteers (12 men; median age, 56.5 years) and 10 OPD patients (five men; median age, 59.5 years). Upper esophageal sphincter (UES) relaxation parameters were measured using a standard HRIM protocol. Peristalsis and bolus transit of the pharyngoesophageal (PE) segment were assessed using an HRIM-modified protocol in which the catheter was pulled back 10 cm. PE bolus transits were evaluated with an impedance contour pattern (linear vs. stasis) method. A significant difference was observed between the manometric measures of healthy volunteers and OPD patients for only the duration of pharyngeal contraction (0.49 ± 0.19 vs. 0.76 ± 0.33 s, P = 0.04). The percentage agreement and kappa value for detecting pharyngeal residue between the VFSS and the impedance analysis were 100% and 1.00, respectively. HRIM allowed for comprehensive assessment of abnormal pharyngeal components that caused pharyngeal residue on VFSS in two patients; reduced base of the tongue versus weak pharyngeal contraction in one, and reduced relaxation of the UES versus reduced laryngeal elevation in the remaining patient. Our findings demonstrated that HRIM using a simple methodology (i.e., pull-back of the catheter) detected pharyngeal residue through a simple analysis of the impedance contour pattern (linear vs. stasis). Furthermore, HRIM facilitated a comprehensive assessment of OPD mechanisms and recognition of subtle abnormalities not yet visible to the naked eye on VFSS.

Endoscopic submucosal dissection using a thulium laser: preliminary results of a new method for treatment of gastric epithelial neoplasia.

BACKGROUND AND STUDY AIM This study aimed to evaluate the feasibility of a novel laser system for endoscopic submucosal dissection (ESD) of gastric epithelial neoplasia. PATIENTS AND METHODS A total of 10 patients underwent ESD by a single expert endoscopist. A thulium 2-μm wavelength laser system was used for ESD procedures. Instead of using endoscopy knives, a 550-μm flexible silica fiber was inserted through the working channel of the endoscope. RESULTS In all patients, ESD was completed using only the thulium laser, without the need for endoscopy knives. The median total procedure time was 49 minutes (range 35 - 203). In 8 /10 patients (80 %), no active bleeding was observed during ESD. The final pathologic mapping revealed low-grade dysplasia (n = 4), differentiated adenocarcinoma (n = 5), and signet ring cell carcinoma (n = 1). Curative resection was achieved in 9 /10 patients (90 %). There were no significant complications, such as delayed bleeding or perforation. CONCLUSIONS The thulium laser system was feasible in ESD of gastric epithelial neoplasia.

ESD Around the World: Asia

Endoscopic submucosal dissection (ESD) improves the quality of life of patients with early gastric cancer (EGC) and dysplasia by preserving gastric function. ESD in the treatment of EGC and dysplasia has become standard in Japan and Korea and is being developed and implemented in many major centers in Asia. With a well-designed prospective study, long-term outcomes of expanded criteria for endoscopic resection of EGC are expected to provide reliable indications for endoscopic treatment. Ongoing and novel clinical investigations of minimally invasive approaches and close collaboration between Western and Asian countries are expected to establish the best way to treat EGC.

How to predict adequate bowel preparation before colonoscopy using conventional polyethylene glycol: prospective observational study based on survey.

The present study investigated the conditions and predictive factors for adequate bowel preparation using 4‐L polyethylene glycol (PEG) preparation in clinical practice.