High-resolution manometry

Pressure topography plot during a normal swallow, measured using a 36-channel high-resolution manometry system

High-resolution manometry (HRM) is a technique used in gastroenterology to evaluate the function of the esophagus and the lower esophageal sphincter (LES). It represents an advancement over traditional manometry by providing a more detailed and precise measurement of esophageal pressure dynamics. HRM is primarily used to diagnose motility disorders of the esophagus, including achalasia, esophageal spasm, and gastroesophageal reflux disease (GERD).

Overview

High-resolution manometry utilizes a catheter equipped with multiple pressure sensors spaced closely together. This catheter is inserted through the nose and positioned in the esophagus and stomach. As the patient swallows, the sensors measure the pressure exerted along the length of the esophagus, providing a detailed, topographical representation of esophageal motility. This data is then analyzed and displayed as a color-coded map, known as a Clouse plot or esophageal pressure topography (EPT).

Clinical Applications

HRM is used in the diagnosis and management of various esophageal motility disorders. It is particularly useful in the evaluation of patients with symptoms of dysphagia (difficulty swallowing), non-cardiac chest pain, and pre-operative assessment before anti-reflux surgery. HRM can help in distinguishing between different types of motility disorders, which is crucial for determining the appropriate treatment.

Achalasia

In patients with achalasia, HRM shows a failure of the LES to relax properly during swallowing and a lack of normal esophageal peristalsis. This information is vital for confirming the diagnosis and planning treatment, such as pneumatic dilation or surgical myotomy.

Esophageal Spasm

HRM can identify abnormal contractions in the esophagus, such as those seen in diffuse esophageal spasm or jackhammer esophagus. These findings help in differentiating these conditions from other causes of chest pain and dysphagia.

GERD

While 24-hour pH monitoring is the gold standard for diagnosing GERD, HRM can provide valuable information about the function of the LES and the esophagus, which may contribute to reflux symptoms.

Advantages over Traditional Manometry

High-resolution manometry offers several advantages over traditional manometry, including:

• Improved sensitivity and specificity in diagnosing esophageal motility disorders.
• The ability to provide a comprehensive view of esophageal pressure dynamics in a single test.
• Enhanced patient comfort due to the use of thinner, more flexible catheters.

Limitations

Despite its benefits, HRM has some limitations. It is a specialized procedure that requires specific equipment and expertise, which may not be available in all medical centers. Additionally, the interpretation of HRM data can be complex and requires significant experience.

Conclusion

High-resolution manometry has revolutionized the diagnosis and management of esophageal motility disorders. By providing detailed and accurate measurements of esophageal function, HRM has become an essential tool in gastroenterology.