Classifying Esophageal Motility by FLIP Panometry: A Study of 722 Subjects With Manometry

Abstract

Introduction: Functional luminal imaging probe (FLIP) panometry can evaluate esophageal motility in response to sustained esophageal distension at the time of sedated endoscopy. This study aimed to describe a classification of esophageal motility using FLIP panometry and evaluate it against high-resolution manometry (HRM) and Chicago Classification v4.0 (CCv4.0).

Methods: Five hundred thirty-nine adult patients who completed FLIP and HRM with a conclusive CCv4.0 diagnosis were included in the primary analysis. Thirty-five asymptomatic volunteers ("controls") and 148 patients with an inconclusive CCv4.0 diagnosis or systemic sclerosis were also described. Esophagogastric junction (EGJ) opening and the contractile response (CR) to distension (i.e., secondary peristalsis) were evaluated with a 16-cm FLIP during sedated endoscopy and analyzed using a customized software program. HRM was classified according to CCv4.0.

Results: In the primary analysis, 156 patients (29%) had normal motility on FLIP panometry, defined by normal EGJ opening and a normal or borderline CR; 95% of these patients had normal motility or ineffective esophageal motility on HRM. Two hundred two patients (37%) had obstruction with weak CR, defined as reduced EGJ opening and absent CR or impaired/disordered CR, on FLIP panometry; 92% of these patients had a disorder of EGJ outflow per CCv4.0.

Discussion: Classifying esophageal motility in response to sustained distension with FLIP panometry parallels the swallow-associated motility evaluation provided with HRM and CCv4.0. Thus, FLIP panometry serves as a well-tolerated method that can complement, or in some cases be an alternative to HRM, for evaluating esophageal motility disorders.

Figure 1.. FLIP Panometry esophageal motility classifications.

FLIP Panometry contractile response patterns. FLIP Panometry output from four patients (A-D) is displayed as length (16-cm) x time x color-coded diameter FLIP topography (top panels) with corresponding FLIP pressure (bottom panel); the corresponding high-resolution manometry (HRM) findings are described, but not displayed. A displays a patient with a normal contractile response (CR) with repetitive antegrade contractions and normal esophagogastric junction (EGJ) opening (NEO); classified as normal FLIP Panometry. This patient had normal esophageal motility on high-resolution manometry (HRM). In B, there is an absent CR and NEO; classified as weak FLIP Panometry. This patient had an HRM with absent contractility. In C, there is an impaired-disordered CR and reduced EGJ opening (REO), classified as obstruction with weak CR. This patient had type II achalasia on HRM. In D, there is a spastic-reactive CR with sustained occluding contractions. This patient had type III achalasia on HRM. DI – distensibility index. Figure used with permission from the Esophageal Center of Northwestern.

Figure 2.. FLIP Panometry classification of esophageal motility.

A combination of the FLIP Panometry contractile response pattern and esophagogastric junction (EGJ) opening classification was applied to classify esophageal motility. Findings associated with clinical uncertainty (i.e. gray zones) were classified as inconclusive. REO – reduced EGJ opening. BrEO – borderline reduced EGJ opening. BnEO – borderline normal EGJ opening. NEO – normal EGJ opening. CR – contractile response. IDCR – impaired/disordered CR. Figure used with permission from the Esophageal Center of Northwestern.

Figure 3.. Association between FLIP Panometry findings and Chicago Classification v4.0 (CCv4.0) high-resolution manometry (HRM) diagnoses.

The number of patients (n) and associated diagnoses per CCv4.0 are shown in each box. EGJ – esophagogastric junction; EGJOO - EGJ outflow obstruction. DES – distal esophageal spasm. HE – hypercontractile esophagus. IEM – ineffective esophageal motility. REO – reduced EGJ opening. BrEO – borderline reduced EGJ opening. BnEO – borderline normal EGJ opening. NEO – normal EGJ opening. CR – contractile response. Figure used with permission from the Esophageal Center of Northwestern.

Figure 4.. Chicago Classification version 4.0 (CCv4.0) diagnoses among FLIP Panometry motility classifications.

Each pie chart represents a FLIP Panometry motility classification with proportions of conclusive CCv4.0 diagnoses (which are grouped by similar features for display purposes). Data labels represent number of patients. EGJOO - EGJ outflow obstruction. DES – distal esophageal spasm. CR – contractile response. Figure used with permission from the Esophageal Center of Northwestern.

Figure 5.. Clinical application of FLIP Panometry findings.

*The FLIP Panometry motility classification is intended for clinical scenarios in which findings associated with secondary esophageal motor abnormalities, such as large hiatal hernia, stricture, or previous foregut surgery, are excluded based on endoscopy and clinical history. GERD – gastroesophageal reflux disease. HRM – high resolution manometry. TBE – timed barium esophagram. DES – distal esophageal spasm. CR – contractile response.