Efficacy & Safety of Submucosal Endoscopic Myotomy With Mucosal Flap (SEMF) in the Treatment of Patients With Achalasia

The purpose of this study is to learn about the safety and usefulness of a procedure called
endoscopic submucosal myotomy, which is a new technique in the treatment of achalasia.
Achalasia is a disorder involving the lack of smooth muscle relaxation and sustained high
pressure in the sphincter (muscle) of the lower esophagus. This may result in symptoms such
as difficulty in swallowing, chest pain, regurgitation of food and eventually, weight loss.

For more than a decade, a laparoscopic surgical procedure known as Heller myotomy has been
the primary treatment for achalasia in patients with low surgical risk. In Heller myotomy,
the surgeon makes three to four small abdominal incisions, inserts tube-like instruments
through them, and once inside, the junction between the esophagus and stomach is found, a
lengthwise incision is made on the muscular ring surrounding the lower esophageal sphincter
which weakens the muscle and the lower esophageal sphincter or muscle (LES) is then able to
open more easily. However, there is an emerging field known as natural orifice (opening)
transluminal (through the lumen) endoscopic surgery (NOTES). This approach involves passing
an endoscope - a thin tube with a built-in camera, light and minuscule tools through the
natural opening in the body, like the mouth in order to perform less invasive surgery
without any external wounds or scars. The procedure is done using the Submucosal Endoscopy
with Mucosal Flap (SEMF) technique which involves passing an endoscope through the mouth
into the esophagus, where a small incision is made on the lining of the esophagus, known as
the mucosa. A balloon is then inserted and dilated in the submucosa - the layer between the
inner lining of the esophagus and the outer wall consisting of the muscle of the esophagus.
Dilation of the balloon in the submucosa creates a tunnel that allows insertion of the
endoscope and access to the muscle of the lower esophageal sphincter (LES). A long incision
is then carefully made on the posterior portion of the muscular ring that forms the LES. The
incision divides the muscle fibers of the LES, which weakens the muscle, allowing for the
easier passage of food while preserving some valve function to prevent reflux of acid from
the stomach into the esophagus.

The expected duration of participation is up to 10 years from the time study participants
undergo the endoscopic surgical procedure.