Validation of secondary peristalsis classification using FLIP panometry in 741 subjects undergoing manometry

Abstract

The functional luminal imaging probe (FLIP) utilizes impedance planimetry technology to assess lumen dimensions along the length of the esophagus and esophageal distensibility (ie, the relationship of dimension with distensive pressure) during controlled volumetric distension. We developed a technique to assess esophageal motility using FLIP and a volume distention protocol, FLIP panometry,

Functional Luminal Imaging Probe (FLIP) as an Adjunctive Modality in Evaluation of Esophageal Dysmotility

“…17,[21][22][23] Secondary peristalsis functions to clear the esophagus of retained or refluxed esophageal contents and maintain an empty esophagus. 21,22,[24][25][26] On the other hand, primary peristalsis (which is typically evaluated by HRM) is the principle form of esophageal motility triggered by swallowing that facilitates bolus transit to the stomach. 11 Similar to primary peristalsis, abnormal secondary peristalsis can lead to dysphagia and pathologic acid reflux.…”

“…Esophageal contractile activity in response to distension (ie, secondary peristalsis) can be characterized via FLIP Panometry contractile response patterns (Figure 4). 26 With FLIP, secondary peristalsis can be visualized by sequenced reduction in esophageal diameters that occur in an antegrade direction, that is, antegrade contractions (ACs). ACs often generate an increase in FLIP pressure and also often are associated with dynamic EGJ opening.…”

“…A classification of the FLIP Panometry contractile response patterns was recently described and demonstrated to carry shared features with primary peristalsis defined by HRM. 26 These contractile responses were defined using a standardized FLIP protocol that involved incremental filling of the FLIP to 50, 60, and 70 ml while maintaining each fill volume for 30 to 60 seconds (and preferably 60 seconds each volume). The contractile response pattern was then assigned based on FLIP Panometry contractile features observed on the global assessment of the study including the 50, 60, and 70 ml fill volume (Figure 4).…”

“…The normal contractile response (NCR) is defined by the RAC Rule-of-6s: ≥6 consecutive ACs that are ≥6 cm in axial length at a rate of 6 ± 3 contractions per minute. 26 In some cases, distinct ACs occur, but not in a RAC pattern, and while this is generally associated with normal primary peristalsis (and can be observed in a minority of healthy controls), this is labeled as a borderline contractile response (BCR). Otherwise, abnormal FLIP Panometry contractile response patterns include an impaired/disordered contractile response (IDCR), that is, when contractility occurs, but without distinct ACs or spastic-reactive features or an absent contractile response (ACR), that is, absence of contractility.…”

“…Finally, there are several additional abnormal contractile response features that are associated with spastic motor disorders, but are also thought to potentially occur as a reactive response (eg, such as to mechanical obstruction, hiatal hernia, or reflux) and thus are included among a classification of spastic-reactive contractile response (SRCR). 26,31 These "spastic-reactive" features include: repetitive retrograde contractions (RRCs), sustained LES contractions (sLESCs), and sustained occluding contractions (SOCs); Table 1 and Figure 4. 26 Overall, these FLIP Panometry contractile response patterns provide a method to categorize secondary peristalsis on FLIP Panometry that is amenable to pattern recognition and also parallel primary peristalsis function, as demonstrated in a validation study including 741 subjects that completed both FLIP Panometry and HRM.…”