Impact of spatial resolution on results of esophageal high-resolution manometry
H U De Schepper1, B F Kessing, P W Weijenborg
1Department of Gastroenterology and Hepatology, Academic Medical Center Amsterdam, Amsterdam, The Netherlands; Department of Gastroenterology and Hepatology, University Hospital Antwerp, Edegem, Belgium.
Insights
The Chicago classification for esophageal motility disorders remains valid with 2-cm spacing, but requires adjustments for lower resolution manometry systems (3-cm or 4-cm spacing). This impacts diagnosis and normal values.
Area of Science:
- Gastroenterology
- Esophageal Physiology
- Medical Diagnostics
Background:
- The Chicago classification for esophageal motility disorders was developed using high-resolution manometry with 1-cm sensor spacing.
- Many international laboratories utilize manometry catheters with lower spatial resolution.
- This discrepancy raises questions about the applicability of the Chicago classification in diverse clinical settings.
Purpose of the Study:
- To evaluate the impact of varying spatial resolutions on Chicago classification metrics and diagnostic accuracy.
- To determine if the Chicago classification remains valid with reduced manometry catheter resolution.
Main Methods:
- Retrospective analysis of high-resolution esophageal manometry studies from 20 healthy volunteers and 47 patients.
- Manometry data were reanalyzed with sensor spacings of 1 cm, 2 cm, 3 cm, and 4 cm.
- Intra-class correlation coefficients (ICC) and Kappa values were calculated to assess agreement.
Main Results:
- A very strong correlation was observed between 1-cm and 2-cm sensor spacing for all Chicago metrics and diagnoses in healthy volunteers and patients.
- Increasing sensor spacing to 3 cm and 4 cm resulted in a moderate correlation, particularly affecting contractile front velocity and peristaltic break size.
- The 2-cm spacing demonstrated high reliability for Chicago metrics and diagnoses.
Conclusions:
- The Chicago classification for esophageal motility disorders is robust and applicable with 2-cm sensor spacing, allowing the use of existing normal values.
- Adjustments to the classification criteria and normal values are necessary for manometry systems with sensor intervals of 3 cm or greater.
- This research provides guidance for interpreting esophageal manometry data across different catheter resolutions.
Background:
The Chicago classification for esophageal motility disorders was designed for a 36-channel manometry system with sensors spaced at 1 cm. However, many motility laboratories outside the USA use catheters with a lower resolution in the segments outside the esophagogastric junction. Our aim was to investigate the effect of spatial resolution on the Chicago metrics and diagnosis.
Methods:
In 20 healthy volunteers and 47 patients with upper gastrointestinal symptoms, high-resolution manometric studies of the esophagus were retrospectively reanalyzed using the original 1-cm spacing in the segments outside the 7-cm esophagogastric junction segment, and again after manually increasing the spacing between sensors to 2, 3, and 4 cm (above the lower esophageal sphincter region). Measurements were analyzed in random order and the investigator was blinded to the outcome of the analyses performed in another resolution of the same patient. Intra-class correlation coefficients (ICC) and Kappa values were determined.
Key Results:
There was a very strong correlation between the 1-cm and 2-cm analysis for all Chicago metrics studied in healthy volunteers (ICCs: distal contractile integral 0.998; contractile front velocity (CFV) 0.964; distal latency 0.919; peristaltic break size 0.941). The 2-cm spacing analysis also correlated very well with the 1-cm analysis for the different Chicago diagnoses obtained in the patients (Kappa values ranging from 0.665 to 1.000). When the sensor spacing was increased to 3 and 4 cm, the correlation was reduced to moderate for the Chicago metrics, especially for break size and CFV of peristalsis.
Conclusions & Inferences:
The Chicago classification for esophageal motility disorders is still valid and the same normal values can be used when catheters with a slightly lower resolution are used (i.e., 2-cm vs 1-cm spacing). For larger sensor intervals, the classification and the normal values will need to be adjusted.
