Background: Treatment for Achalasia is aimed at the lower esophageal sphincter (LES), although little is know about the affect, if any, of these treatments on esophageal body function (peristalsis and clearance). We sought to measure the affect of various treatments using combined manometry (peristalsis) with Multichannel Intraluminal Impedance (MII) (esophageal clearance).
Methods: We enrolled 56 patients with Achalasia referred to the University of Washington Swallowing Center between January 2003 and January 2006. Each was grouped according to prior treatment: 38 were untreated (Primary Achalasia), 10 had undergone botox injection or balloon dilation, and 16 a laparoscopic Heller Myotomy. The preoperative studies for 8 of the Myotomy patients were included in the Primary Achalasia group. Each patient completed a dysphagia severity questionnaire (scale 0-10); peristalsis was analyzed by manometry and esophageal clearance of liquid and viscous material by MII.
Results: Mean dysphagia severity scores were significantly better in patients after Heller Myotomy than in either of the other groups. Peristaltic contractions were seen in significantly greater numbers of both Heller Myotomy and Botox/Dilation patients compared to Primary Achalasia, and liquid and viscous clearance rates were significantly better as well (Table). Similar trends were observed in the above parameters for the subset of patients who underwent manometry/MII both pre- and post-Heller Myotomy, but the sample size was too small for these to be significant. In the overall Myotomy group, rates of peristalsis weakly correlated with liquid clearance (r=0.46, p=0.09) and more strongly with viscous bolus clearance (r=0.63, p<0.05). There was no correlation between peristalsis and bolus clearance in the Botox/Dilation group.
Conclusions: With treatment Achalasia patients exhibit some restoration in peristalsis as well as improved bolus clearance. After Heller Myotomy, the return of peristalsis correlates with esophageal clearance, which may partly explain its superior relief of dysphagia.

Group	Dysphagia Severity	% With Peristalsis	% Liquid Clearance	% Viscous Clearance
Primary Achalasia	6.5	8%	5%	2%
Botox/Dilation	5.3*	40%*	16%*	11%*
Heller Myotomy	2.0†	63%*	28%*	19%*

*p<0.05 vs. Primary Achalasia†p<0.005 vs. Primary Achalasia and Botox/Dilation