An axial CT image showing marked dilatation of the esophagus in a person with<unk> . Due to the similarity of symptoms,<unk>  can be mistaken for more common disorders such as gastroesophageal reflux disease (GERD), hiatus hernia, and even psychosomatic disorders. Specific tests for<unk>  are barium swallow and esophageal manometry. In addition, endoscopy of the esophagus, stomach, and duodenum (esophagogastroduodenoscopy or EGD), with or without endoscopic ultrasound, is typically performed to rule out the possibility of cancer. The internal tissue of the esophagus generally appears normal in endoscopy, although a "pop" may be observed as the scope is passed through the non-relaxing lower esophageal sphincter with some difficulty, and food debris may be found above the LES. Barium swallow "Bird's beak" appearance and "megaesophagus", typical in<unk> .The patient swallows a barium solution, with continuous fluoroscopy (X-ray recording) to observe the flow of the fluid through the esophagus. Normal peristaltic movement of the esophagus is not seen. There is acute tapering at the lower esophageal sphincter and narrowing at the gastro-esophageal junction, producing a "bird's beak" or "rat's tail" appearance. The esophagus above the narrowing is often dilated (enlarged) to varying degrees as the esophagus is gradually stretched over time. An air-fluid margin is often seen over the barium column due to the lack of peristalsis. A five-minutes timed barium swallow can provide a useful benchmark to measure the effectiveness of treatment. Esophageal manometry aperistaltic contractions, increased intraesophageal pressure, and failure of relaxation of the lower esophageal sphincter. Because of its sensitivity, manometry (esophageal motility study) is considered the key test for establishing the diagnosis. A catheter (thin tube) is inserted through the nose, and the patient is instructed to swallow several times. The probe measures muscle contractions in different parts of the esophagus during the act of swallowing. Manometry reveals failure of the LES to relax with swallowing and lack of functional peristalsis in the smooth muscle esophagus. Characteristic manometric findings are: * Lower esophageal sphincter (LES) fails to relax upon wet swallow (100 is considered<unk> , > 200 is nutcracker<unk> . * Aperistalsis in esophageal body * Relative increase in intra-esophageal pressure as compared with intra-gastric pressure Biopsy Biopsy, the removal of a tissue sample during endoscopy, is not typically necessary in<unk>  but if performed shows hypertrophied musculature and absence of certain nerve cells of the myenteric plexus, a network of nerve fibers that controls esophageal peristalsis. It is not possible to diagnose<unk>  by means of biopsy alone.
Esophageal achalasia
Esophageal spasm
Nutcracker esophagus
Esophagogastric junction outflow obstruction
Esophageal web
Megaesophagus
Diffuse esophageal spasm
Esophageal stricture