Background: The existence of endosonographic abnormalities of the oesophagus in achalasia is discussed. The place of endoscopic ultrasonography (EUS) needs to be clarified.
Patients: Thirty five untreated patients suffering from achalasia and 28 controls without oesophageal disease were prospectively enrolled since 1993. Pseudoachalasia was diagnosed in two patients.
Methods: EUS measurements were performed at two opposite sites at the level of the cardia, and 5 cm and 10 cm proximally, avoiding compression by the water filled balloon.
Results: The oesophageal wall and the fourth hypoechoic layer were significantly thicker at the level of the cardia and 5 cm above, with mean differences between patients and controls of 0.37/0.42 mm and 0.16/0.23 mm respectively. No statistically significant correlation could be demonstrated between the thickness of the oesophageal wall or of the fourth hypoechoic layer and weight loss, or the average pressure of the lower oesophageal sphincter. However, a significant inverse relationship was demonstrated between the duration of symptoms and the thickness of the fourth hypoechoic layer. The thickness of the fourth hypoechoic layer was also increased in patients who required only one pneumatic dilatation (P < 0.01).
Conclusion: The thickness of the oesophageal wall and of the fourth hypoechoic layer appeared to be significantly increased in achalasia patients. However, the slight increase of the mean size (< 0.5 mm) of the muscularis propria suggests that EUS is not helpful in the diagnosis of achalasia. The physiopathological basis of advanced achalasia has to be reconsidered as we demonstrated an inverse relationship between the duration of symptoms and the thickness of the muscularis propria.