Tu1983 Correlation of Esophageal Diameter With Manometric Parameters in Subtypes of Achalasia Patients

Abstract

Background: It was commonly thought that significantly dilated esophagus in Achalasia is associated with prolonged disease process. Comparing to type II Achalasia, type I diagnosed by manometry is thought to be a later stage achalasia which is less responsive to the treatment. Objective: To compare the esophageal diameter in different subtypes of achalasia based on High Resolution Impedance Manometry (HRIM) and therefore to further determine the clinical significance of this radiographic parameter. Method: Data of HRIM findings and esophagram of 71 Achalasia patients were retrospectively analyzed. Following parameters were obtained: height of the bolus column based on impedance recordings, lower esophageal sphincter residual pressure i.e. integrated relaxation pressure (IRP), and pan-esophageal pressure in supine and upright positions. The largest esophageal diameter was measured above esophagogastric (EG) junction on anteroposterior (AP) view of esophogram images. The patients were separated into 3 groups based on diameter of the esophagus as 8cm. The above manometric findings were compared with esophageal diameter. Esophageal diameter was also compared in different subtypes of Achalasia. Results: Thirty three out of 71 Achalasia patients with available esophogram were studied (M:F 15:18, age range 20-88 years; mean 58.6). Of these 33 patients, 6 patients were type I, 20 were type II, and 5 were type III Achalasia based on Chicago classification. Two patients were labeled as unclassified Achalasia due to presence of segmental peristalsis. Unexpectedly, Achalasia patients with wider esophageal diameter were more commonly seen in type II Achalasia rather than type I Achalasia as shown in table 1. 16 out of 20 type II Achalasia patients (80%) had dilated esophagus ≥ 5cm; comparing to 3 out of 6 type I patients (50%), and 1 out of 5 type III patients (20%) who had dilated esophagus of ≥ 5cm. There was no statistically significant correlation between esophageal diameter and LES residual pressure and pan esophageal pressures in both supine and upright swallows. However, the bolus height as determined by HRIM in upright position was associated with wider esophageal diameter on barium esophagram with correlation factor of 0.387 (P=0.07). Conclusion: In this study, we showed that wider esophageal diameter was associated with greater height of the bolus column in the upright position. Type II Achalasia patients are more commonly seen with larger esophageal diameter than other types. Since type II Achalasia responds to treatment better than other types, the degree of esophageal dilatation may not be a reliable prognosis predictor for Achalasia patients. Table 1. Correlation of esophageal diameter with subtypes of Achalasia