High-resolution colonic manometry interobserver analysis trial

Colonic high-resolution manometry (HRM) is a novel, not widely used diagnostic method used in the final workup of chronic constipation before surgery. Since its introduction, different motor patterns have been defined. However, it remains to be established whether these patterns are easily and reproducibly identified by different investigators.

The primary aim of this study was to determine agreement for motor pattern identification with HRM. To calculate the interobserver agreement (IOA), the Fleiss's kappa statistic for multiple observers was used. Seven participants analyzed 106 one-min time frames, derived from five measurements in healthy volunteers and five in patients with chronic constipation. The time frames were chosen to show a variety and combination of motor patterns consisting of short antegrade, short retrograde, cyclic anterograde, cyclic retrograde, long antegrade, long retrograde, slow retrograde motor pattern, high-amplitude propagating motor patterns, and pancolonic pressurizations. All of the measurements were performed with a solid-state colonic HRM catheter, comprising 40 pressure sensors spaced 2.5 cm apart.

A median of 10.25 h (range 6-20) were required to analyze all time frames. High-amplitude propagating contractions achieved an almost perfect level of agreement (k = 0.91). Several motor patterns achieved substantial agreement; these included the short antegrade (k = 0.63), long antegrade (k = 0.68), cyclic retrograde (k = 0.70), slow retrograde motor pattern (k = 0.80), and abdominal pressure or movement artifacts (k = 0.67). Moderate agreement was found for short retrograde (k = 0.57), cyclic anterograde (k = 0.59), long retrograde motor patterns (k = 0.59) and simultaneous pressure waves (k = 0.59).

For the majority of motor patterns, the overall IOA for colonic manometry was substantial or high. This high level of agreement supports the use of colonic manometry application in clinical and research settings. Harmonization has the potential to improve agreement for long anterograde motor patterns with high amplitudes and for mixed direction patterns.