Achalasia is a primary esophageal motility disorder characterized by impaired relaxation of the lower esophageal sphincter (LES) and loss of peristalsis in the esophageal body. It develops due to degeneration or loss of ganglion cells in the Auerbach (myenteric) plexus. Incidence is 1-3/100,000 per year. Most commonly occurs between ages 25-60; no significant gender predilection. Most patients present with progressive dysphagia (both solids and liquids), regurgitation, chest pain, and weight loss. Barium esophagram is the gold standard for diagnosis — the 'bird-beak' appearance at the distal esophagus and proximal esophageal dilation is pathognomonic. Treatment options include pneumatic dilation, Heller myotomy, and peroral endoscopic myotomy (POEM). Long-standing achalasia increases the risk of esophageal squamous cell carcinoma 10-50 fold.
Age Range
20-60
Peak Age
40
Gender
Equal
Prevalence
Uncommon
The fundamental pathophysiological mechanism of achalasia is the loss of inhibitory ganglion cells (neurons secreting nitric oxide and vasoactive intestinal peptide) in the esophageal myenteric plexus through autoimmune or neurodegenerative processes. The absence of these inhibitory neurons eliminates the relaxation capacity of the lower esophageal sphincter and disrupts coordinated peristaltic contraction of esophageal smooth muscle. As a result, the esophageal body becomes aperistaltic and LES basal tone remains elevated. Due to chronic obstruction, the esophageal body progressively dilates and assumes a sigmoid configuration. This dilation produces the 'bird-beak' appearance on barium esophagram: the distal segment narrows while the proximal segment widens. On CT, food debris and air-fluid levels within the dilated esophagus reflect this stasis pattern. Prolonged mucosal irritation and stasis increase the risk of squamous cell carcinoma development.
Smooth, symmetric, tapered narrowing at the distal esophagus toward the gastroesophageal junction on barium esophagram. Reflects functional obstruction of the lower esophageal sphincter. The esophagus is dilated proximally. This appearance is pathognomonic for achalasia and is easily distinguished from malignant stricture (irregular borders, asymmetry, mucosal destruction).
Bird-beak appearance at the distal esophagus: smooth, symmetric, tapered narrowing toward the gastroesophageal junction. No mucosal irregularity or asymmetry at the narrowing. The narrowing is typically 1-3 cm in length. The esophageal body proximal to the narrowing is markedly dilated.
Report Sentence
Smooth tapered narrowing at the distal esophagus at the gastroesophageal junction level (bird-beak sign) with proximal esophageal body dilation is observed; findings are consistent with achalasia.
Marked dilation of the esophageal body (diameter >4 cm, >7 cm in advanced stages). Food debris, barium-food mixture, and air-fluid levels are seen within the dilated esophagus. In advanced stages, the esophagus assumes sigmoid configuration (megaesophagus). No peristaltic waves are visible (aperistalsis).
Report Sentence
The esophageal body is markedly dilated (diameter approximately ___ cm) with food debris and air-fluid levels within the lumen; with aperistalsis, findings suggest achalasia.
Markedly dilated esophageal lumen on CT (>3 cm). Heterogeneous intraluminal density: air, fluid, and food debris coexist. Air-fluid levels are visible. The esophageal wall is typically of normal thickness or mildly thinned without irregular thickening. Progressive narrowing at the distal esophagus.
Report Sentence
The esophageal lumen is markedly dilated (diameter ___ cm) with food debris and air-fluid levels intraluminally; wall thickness is preserved, consistent with achalasia.
Smooth, symmetric narrowing at the distal esophagus on contrast-enhanced CT. The esophageal wall at the narrowing is of normal thickness with homogeneous enhancement — no asymmetric thickening or irregular enhancement. Abrupt transition at the gastroesophageal junction level.
Report Sentence
Smooth symmetric narrowing at the distal esophagus at the gastroesophageal junction with normal wall thickness and homogeneous enhancement; malignant obstruction is excluded.
In advanced achalasia, the esophagus assumes sigmoid configuration (megaesophagus). Esophageal diameter may reach >7 cm. Appears as mass-like dilation in the mediastinum. May displace trachea and mediastinal structures. Aspiration pneumonia findings may be associated.
Report Sentence
The esophagus is severely dilated (diameter >___ cm) with sigmoid configuration; consistent with megaesophagus, suggesting advanced achalasia.
On T2-weighted sequences, stasis fluid within the esophageal lumen appears hyperintense. The dilated esophagus is seen as a markedly hyperintense tubular structure in the mediastinum. Food debris shows heterogeneous signal. Wall structure is preserved with intermediate signal intensity on T2.
Report Sentence
The esophageal lumen is dilated on T2-weighted sequences with hyperintense stasis fluid intraluminally; wall structure is preserved, consistent with achalasia.
Criteria
Impaired LES relaxation + 100% failed peristaltic contractions + minimal esophageal body pressurization
Distinct Features
Marked esophageal dilation on barium, minimal contractile activity. Megaesophagus in advanced stages. Good response to treatment.
Criteria
Impaired LES relaxation + 100% failed peristalsis + pan-esophageal pressurization in ≥20% of swallows
Distinct Features
Less esophageal dilation, simultaneous contraction pattern visible. Best treatment response (>90% success). Compartmentalized appearance on barium.
Criteria
Impaired LES relaxation + premature (spastic) contractions in ≥20% of swallows
Distinct Features
Corkscrew appearance on barium, segmental spasm. Minimal esophageal dilation. Lowest treatment response. POEM preferred.
Criteria
Achalasia-like findings due to gastroesophageal junction carcinoma or submucosal infiltration
Distinct Features
>60 years, rapidly developing dysphagia (<6 months), weight loss. Asymmetric wall thickening at GEJ on CT. Endoscopy mandatory.
Distinguishing Feature
SCC shows asymmetric, irregular wall thickening with heterogeneous enhancement; distinguished from achalasia's smooth symmetric narrowing and normal wall thickness
Distinguishing Feature
Adenocarcinoma shows mass and irregular wall thickening at distal esophagus; achalasia shows symmetric tapered narrowing without mass
Distinguishing Feature
Benign stricture is usually localized at mucosal damage site, short segment; achalasia shows bird-beak at GEJ and diffuse esophageal dilation
Distinguishing Feature
Esophagitis shows diffuse mucosal thickening and edema; achalasia has normal wall thickness, main findings are dilation and stasis
Urgency
routineManagement
surgicalBiopsy
Not NeededFollow-up
annualAchalasia is a chronic, progressive condition. Treatment options include pneumatic dilation, Heller myotomy (laparoscopic), or peroral endoscopic myotomy (POEM). Type II shows the best treatment response. Endoscopy is recommended to exclude pseudoachalasia (especially >60 years, rapid-onset dysphagia). Long-standing achalasia (>15 years) increases esophageal squamous cell carcinoma risk 10-50 fold; surveillance endoscopy is recommended.
Achalasia is treated with pneumatic dilation, peroral endoscopic myotomy (POEM), or surgical myotomy (Heller). Long-standing achalasia increases SCC risk 16-28 fold — surveillance is required. Pseudoachalasia (GEJ carcinoma) must always be excluded.