Achalasia is a primary esophageal motility disorder manifested by dysphagia and chest pain that impair patients’ quality of life, and it also leads to chronic esophageal inflammation by food retention and increases the risk of esophageal cancer. Although achalasia has long been reported, the epidemiology, diagnosis and treatment of achalasia are not fully understood. The current clinical dilemma of achalasia is mainly due to its unclear pathogenesis. In this paper, epidemiology, diagnosis treatment, as well as possible pathogenesis of achalasia will be reviewed and summarized. The proposed hypothesis on the pathogenesis of achalasia is that genetically susceptible populations potentially have a higher risk of infection with viruses, triggering autoimmune and inflammation responses to inhibitory neurons in lower esophageal sphincter.

Objective:To evaluate the effects of modified peroral endoscopic myotomy (POEM) on esophageal dynamics and clinical efficacy in achalasia (AC) patients.Methods:From January 2013 to December 2014, 51 patients diagnosed with AC and received modified POEM at The First Affiliated Hospital of Sun Yat-sen University were retrospectively enrolled. AC patients were classified as type Ⅰ, type Ⅱ and type Ⅲ according to Chicago classification. The changes of esophageal dynamics before and after the modified POEM were compared by high resolution manometry (HRM). The reflux after the operation was evaluated by 24-hour esophageal impedance-pH monitoring. The clinical symptoms and the quality of life of AC patients were assessed by impaction dysphagia questionnaire (IDQ), Eckardt scale and short-form 36 item health survey (SF-36). Paired t test, independent sample t test, Wilcoxon rank sum test and Pearson correlation analysis were used for statistical analysis. Results:At three months and one year after operation, lower esophageal sphincter pressure (LESP) and integrated relaxation pressure (IRP) were all lower than those before operation ((23.89±12.68) and (23.44±12.56) mmHg (1 mmHg=0.133 kPa) vs. (39.29±16.14) mmHg; (16.13±9.43) and (15.37±8.36) mmHg vs. (30.57±11.31) mmHg), and the differences were statistically significant ( t=7.520, 7.866, 7.641 and 8.909, all P<0.05). There were no statistically significant differences in LESP and IRP during the same period between patients with type Ⅰ AC and type Ⅱ AC (all P>0.05). The LESP of patients with partial esophageal peristalsis function recovered one year after operation was lower than that of patients with unrecovered esophageal peristalsis function ((15.38±4.54) mmHg vs. (25.65±13.19) mmHg), and the difference was statistically significant ( t=0.039, P<0.05). The proportions of pathologic acid reflux of AC patients at three months and one year after operation were 7.8%(4/51) and 2.0%(1/51), respectively. The IDQ and Eckardt scores of patients with AC at three months and one year after operation were both lower than those before operation (4 points, 0 points to 10 points and 4 points, 0 points to 11 points vs. 23 points, 18 points to 30 points; 2 points, 1 points to 3 points and 1 points, 0 points to 1 points vs. 5 points, 4 points to 5 points), and the differences were statistically significant ( Z=-6.036, -6.104, -5.971 and -6.209, all P<0.01). According to Eckardt score, the proportions of clinical remission at three months and one year after operation were higher than that before operation (98.0%, 50/51 and 100.0%, 51/51 vs. 19.6%, 10/51), and the differences were statistically significant ( χ2=64.76 and 68.56, both P<0.05). The SF-36 general health and social function scores at three months and one year after operation were both higher than those before operation (0.55 points, 0.45 points to 0.70 points and 0.55 points, 0.45 points to 0.70 points vs. 0.45 points, 0.30 points to 0.55 points; 0.88 points, 0.75 points to 1.00 points and 0.88 points, 0.75 points to 1.12 points vs. 0.75 points, 0.75 points to 1.00 points); and the differences were statistically significant ( Z=-4.439, -4.225, -2.123 and -2.320, all P<0.05); and the health change scores were lower than those before operation (3.00 points, 2.00 points to 3.00 points and 2.00 points, 1.00 points to 3.00 points vs. 4.00 points, 3.00 points to 4.00 points), and the differences were statistically significant ( Z=-4.827 and -4.841, both P<0.05). Before and after modified POEM, the changes of LESP were positively correlated with the changes of IRP ( r=0.624 and 0.592, both P<0.01). Conclusion:Modified POEM can significantly improve the symptoms and LES relaxation function of AC patients, with a low incidence of post-operative reflux.

Objective:To evaluate the effects of single spay of L-menthol (NPO-11) on suppressing gastric peristalsis during upper gastrointestinal endoscopy and the influencing factor.Methods:This study was a multicenter, randomized, double-blind, placebo-parallel controlled study. The eligible patients were randomly divided into two groups by randomized blocks. Patients received local spray of either NPO-11 (160 mg L-menthol) or placebo 20 mL during upper gastrointestinal endoscopy. The gastric peristalsis was recorded and evaluated before, 2 minutes after and at the end of endoscopy. The complexity of the procedure was evaluated by the researchers. The influencing factors for antiperistaltic effect of NPO-11 were analyzed.Results:A total of 220 patients were enrolled from five research centers. There were 109 cases in the NPO-11 group and 111 cases in the placebo group. The baseline data of the two groups were similar and comparable. The proportion of patients with grade 1 peristalsis at 2 minutes after the treatment and at the end of endoscopy was significantly higher in the NPO-11 group than that in the placebo group [40.37% (44/109) VS 16.22% (18/111), χ2=15.93, P<0.001]. Compared with the placebo group, the proportions of weak peristalsis (grade 1 and 2) were higher in the NPO-11 group at 2 minutes after the treatment [67.89% (74/109) VS 46.85% (52/111)] and at the end of endoscopy [79.82% (87/109) VS 48.65% (54/111)]. Subgroup analysis showed that the inhibitory effect of NPO-11 on gastric peristalsis was more significant in Helicobacter pylori antibody positive group. Conclusion:Local spray of NPO-11 can effectively inhibit gastric peristalsis during upper gastrointestinal endoscopy, and its effect is more significant in Helicobacter pylori antibody positive group. It could be recommended for no obvious adverse reactions , its safety, and the convenient procedure.