Laparoscopic limited Heller myotomy without anti-reflux procedure does not induce significant long-term gastroesophageal reflux.

BACKGROUND: Laparoscopic Heller myotomy with partial fundoplication is the gold standard treatment for achalasia. Laparoscopic limited Heller myotomy (LLHM) with no anti-reflux procedure is another possible option. METHODS: A review of prospectively collected data was performed on patients who underwent LLHM from January 1998 to December 2012. Evaluation included gastroscopy, esophageal manometry, 24-h pH-metry, and the Short Form(36) Health Survey(SF-36) questionnaire at baseline and 6 months, as well as the global symptom score at baseline, 6 months, and 5 years post-surgery. Comparison between outcomes was performed with a paired t student's test. RESULTS: 126 patients underwent LLHM. Of these, 60 patients had complete pre and post-operative motility studies. 57 % were female, patient mean age was 45.7 years, with a mean follow-up of 10.53 months. Mean operative time was 56.1 min, and the average length of stay was 1.7 days. At 6 months, a significant decrease in the lower esophageal sphincter resting pressure (29.1 vs. 7.1 mmHg; p < 0.001) and nadir (16.4 vs. 4.3 mmHg; p < 0.001) was observed. Normal esophageal acid exposure (total pH < 4 %) was observed in 68.3 % patients. Nevertheless, of the remaining 31.7 % with abnormal pH-metry, only 21.6 % were clinically symptomatic and all were properly controlled with medical treatment without requiring anti-reflux surgery. Significant improvement in all pre-operative symptoms was observed at 6 months and maintained over 5 years. Dysphagia score was reduced from 9.8 pre-operatively to 2.6 at 5 years (p < 0.001), heartburn score from 3.82 to 2 (p < 0.01), and regurgitation score from 7.5 to 0.8 (p < 0.001). Only one patient (0.8 %) presented with recurrent dysphagia requiring reoperation. CONCLUSION: LLHM without anti-reflux procedure is an effective long-term treatment for achalasia and does not cause symptomatic GERD in three quarters of patients. The remaining patients are well controlled on anti-reflux medications. It is believed that similar clinical results would be obtained during a clinical investigation of the POEM procedure.

An effusive molecular beam technique for studies of polyatomic gas-surface reactivity and energy transfer.

An effusive molecular beam technique is described to measure alkane dissociative sticking coefficients, S(T(g), T(s); ϑ), on metal surfaces for which the impinging gas temperature, T(g), and surface temperature, T(s), can be independently varied, along with the angle of incidence, ϑ, of the impinging gas. Effusive beam experiments with T(g) = T(s) = T allow for determination of angle-resolved dissociative sticking coefficients, S(T; ϑ), which when averaged over the cos (ϑ)/π angular distribution appropriate to the impinging flux from a thermal ambient gas yield the thermal dissociative sticking coefficient, S(T). Nonequilibrium S(T(g), T(s); ϑ) measurements for which T(g) ≠ T(s) provide additional opportunities to characterize the transition state and gas-surface energy transfer at reactive energies. A resistively heated effusive molecular beam doser controls the T(g) of the impinging gas striking the surface. The flux of molecules striking the surface from the effusive beam is determined from knowledge of the dosing geometry, chamber pressure, and pumping speed. Separate experiments with a calibrated leak serve to fix the chamber pumping speed. Postdosing Auger electron spectroscopy is used to measure the carbon of the alkyl radical reaction product that is deposited on the surface as a result of alkane dissociative sticking. As implemented in a typical ultrahigh vacuum chamber for surface analysis, the technique has provided access to a dynamic range of roughly 6 orders of magnitude in the initial dissociative sticking coefficient for small alkanes on Pt(111).