GI Endoscopy · 1 min read

Chicago Classification (v4.0) of Esophageal Motility Disorders

Learn about esophageal dysphagia, a swallowing disorder that affects the food pipe. Discover common causes, recognize warning signs, and explore effective treatment approaches

Clinical Bottom Line

Motility DiagnosisChicago v4.0 Manometric DefinitionEndoscopic Appearance
Achalasia (Type I)100% failed peristalsis + failed Lower Esophageal Sphincter (LES) relaxation.Dilated, "bird-beak" esophagus filled with retained food; severe popping resistance at the GE junction.
Jackhammer EsophagusHypercontractile, massively forceful sequential spasms.Endoscopically appears completely normal between spasms.

Mapping the Invisible Muscular Failure

When a patient complains of severe dysphagia to both solids and liquids, but a standard upper endoscopy reveals a perfectly normal, pink, stricture-free esophagus, the anatomical structure is intact. The pathology lies in the electrical and muscular coordination of the swallowing sequence. Diagnosing these invisible motor failures requires High-Resolution Manometry (HRM).

The Shift to v4.0 Standardization

HRM involves passing a specialized catheter studded with dozens of pressure sensors deep into the stomach. The patient swallows 10 precise saline boluses. The computer maps the exact physical pressure of each muscular contraction descending down the esophagus. The Chicago Classification v4.0 is the rigid, universally mandated rubric utilized to interpret these pressure plots. It strictly categorizes disorders based on the Integrated Relaxation Pressure (IRP) of the LES. If the LES pressure is persistently high (failing to open) and peristalsis is absent, Achalasia is confirmed, immediately triggering a referral for a curative POEM (Peroral Endoscopic Myotomy).


Clinical guidelines summarized by the Gastroscholar Research Team. Last updated: 2026. This article is intended for physicians.

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