esophagus is made of several layers, and the myotomy cuts only through the outside muscle layers which are squeezing it shut, leaving the inner mucosal layer intact. image of a stomach which has undergone fundoplomy a partial fundoplication or "wrap", where the fundus (part of the stomach which hangs above the connection to the oesophagus) is wrapped around said lower oesophagus and sewn to itself, secured to the diaphragm to create pressure on the sphincter post-myotomy, is generally added in order to prevent excessive reflux, which can cause serious damage to the esophagus over time. after surgery, patients should keep to a soft diet for several weeks to a month, avoiding foods that can aggravate reflux. the most recommended fundoplication to complement heller myotomy is dor fundoplication, which consists of a 180- to 200-degree anterior wrap around the esophagus. it provides excellent results as compared to nissen's fundoplication, which is associated with higher incidence of postoperative dysphagia. the shortcoming of laparoscopic esophageal myotomy is the need for a fundoplication. on the one hand, the myotomy opens the esophagus, while on the other hand, the fundoplication causes an obstruction. recent understanding of the gastroesophageal antireflux barrier/valve has shed light on the reason for the occurrence of reflux following myotomy. the gastroesophageal valve is the result of infolding of the esophagus into the stomach at the esophageal hiatus. this infolding creates a valve that extends from 7 o'clock to 4 o'clock (270 degrees) around the circumference of the esophagus. laparoscopic myotomy cuts the muscle at the 12 o'clock position, resulting in incompetence of the valve and reflux. recent robotic laparoscopic series have attempted a myotomy at the 5 o'clock position on the esophagus away from the valve. the robotic lateral esophageal myotomy preserves the esophageal valve and does not result in reflux, thereby obviating the need for a fundoplication. the robotic lateral esophageal myotomy has had the best results to date in terms of the ability to eat without reflux. endoscopic myotomy a new endoscopic therapy for achalasia management was developed in 2008 in japan. per-oral endoscopic myotomy or poem is a minimally invasive type of natural orifice transluminal endoscopic surgery that follows the same principle as the heller myotomy. a tiny incision is made on the esophageal mucosa through which an endoscope is inserted. the innermost circular muscle layer of the esophagus is divided and extended through the les until about 2 cm into the gastric muscle. since this procedure is performed entirely through the patient's mouth, there are no visible scars on the patient's body. patients usually spend about 1–4 days in the hospital and are discharged after satisfactory examinations. patients are discharged on full diet and generally able to return to work and full activity immediately upon discharge. major complications are rare after poem and are generally managed without intervention. long term patient satisfaction is similar following poem compared to standard laparoscopic heller myotomy. poem has been performed on over 1,200 patients in japan and is becoming increasingly popular internationally as a first-line therapy in patients with achalasia. monitoring even after successful treatment of achalasia, swallowing may still deteriorate over time. the esophagus should be checked every year or two with a timed barium swallow because some may need pneumatic dilatations, a repeat myotomy, or even esophagectomy after many years. in addition, some physicians recommend ph testing and endoscopy to check for reflux damage, which may lead to a premalignant condition known as barrett's esophagus or a stricture if untreated. history of the understanding and treatment of achalasia in 1672, the english physician sir thomas willis, one of the founders of the royal society first described the condition now known as achalasia and treated the problem with a dilation using a sea sponge attached to a whale bone. in 1881, the german polish-austrian physician johann freiherr von mikulicz-radecki described the disease as cardiospasm, and felt it was a functional problem rather than a mechanical one. in 1913, ernest heller became the first person to successfully perform an esophagomyotomy, now known in his namesake as the heller myotomy. in 1929, two physicians – hurt and rake – figured out that the problem was due to the les not relaxing. they named the disease achalasia, meaning inability to relax. in 1937, f.c. lendram affirmed the conclusions of hurt and rake, forwarding the term achalasia over cardiospasm. (hard to say who really changed the name between the last two entries) in 1937, the physician f.c. lendram affirmed the conclusions of hurt and rake in 1929, forwarding the usage of the term achalasia over cardiospasm. in 1955, the german physician rudolph nissen, a student of ferdinand sauerbruch, performs the first fundoplomy, now known in his namesake as the nissen fundoplication, eventually publishing the results of two cases in a 1956 copy of swiss medical weekly. in 1962, the physician dor reports the first anterior partial fundoplication, acting as a solution to the intense post-surgery gerd, and risk of stomach acid inhalation accompanying heller myotomy. in 1963, the physician toupet reports first posterior partial fundoplication. in 1991, the physician shimi and his colleagues perform the first laproscopic heller's in england. in 1994, paricha et al. introduces botox as a method for reducing les pressure. in 2008, the newest method of surgically treating achalasia, the per-oral endoscopic myotomy, was devised by h. inoue in tokyo, japan. this method is currently considered experimental in many countries such as the united states. epidemiology incidence of achalasia has risen to approximately 1.6 per 100,000 in some populations. disease affects mostly adults between ages 30s and 50s. notable patients planetary scientist carl sagan had achalasia from the age of 18. the zambian government announced that the president of zambia edgar lungu has achalasia, bearing symptoms that sometimes occur during official engagements, in particular lightheadedness.