Outcome after treatment of achalasia is usually assessed by the Eckardt score (ES). The timed barium esophagogram (TBE) is used to objectively assess esophageal clearance after treatment. High-resolution manometry with impedancemetry (HRiM) provides information on esophageal clearance of liquids in addition to motility parameters. The aim of this study was to compare esophageal clearance determined by HRiM and TBE in patients with achalasia treated by POEM.

Consecutive patients treated with POEM had pre and post-POEM assessment with ES, TBE, and HRiM. Treatment failure was defined by an ES > 3 at 3 months post-POEM. Incomplete esophageal clearance (IEC) was defined by the presence of an esophageal stasis > 2 cm at 5 minutes in HRiM and/or TBE. The Eckardt score is evaluated at one year to estimate the prognostic value of measurements of esophageal clearance after treatment on long-term symptoms. The evaluation of the Eckardt score will be compared to the quality of life score. All of these examinations are carried out as part of routine care.

The supposed superiority of HRiM in the evaluation of esophageal clearance, systematically carried out in the assessment of Achalasia, could lead to no longer using TBE which is a irradiating examination for the patient.

Inclusion Criteria:

• The patients included are all patients treated by POEM at Bordeaux University Hospital between October 2020 and September 2024.

Exclusion Criteria:

• Primary POEM failure, lost to follow-up, absence of completion of the ES, TBE or HRiM pre or post poem at 3 months.

a single cohort of all patients with achalasia and treated by POEM at Bordeaux University Hospital and having performed HRiM and TBE in routine care