John E. Pandolfino, MD

Chief, Division of Gastroenterology and Hepatology
Northwestern University School of Medicine
Chicago, Illinois


Patients presenting with esophageal complaints, such as heartburn, regurgitation, dysphagia, chest pain, and food impaction invariably will require an endoscopy to help diagnosis and management.1 However, overt pathology in the form of esophagitis (peptic, eosinophilic, infectious, or caustic) or structural/mechanical (stricture, tumor) are found in less than 50% of cases,2 and many patients are not diagnosed after upper endoscopy. The next step in patients with a negative endoscopy is esophageal function testing to assess reflux burden and motor function based on the primary symptom. This approach requires additional outpatient visits and uncomfortable transnasal intubation.3 Recently, functional lumen imaging probe (Flip™) technology has been adapted to provide both a comprehensive evaluation of the mechanical properties of the esophagus and a simple assessment of esophageal motility that can diagnose achalasia with similar accuracy to manometry.4 Using Flip™, one potentially could avoid additional uncomfortable testing and streamline the workup to focus on the index endoscopy. This approach has been useful in patients who do not tolerate a transnasal catheter and patients with equivocal results on manometry and esophagram.

Case Presentation

A 45-year-old man presents with a 9-month history of regurgitation, heartburn, and chest fullness. He has a history of hypertension and currently is taking a lovastatin for hypercholesterolemia. He recently underwent a stress echocardiogram to rule out ischemia and this was negative. He underwent an upper endoscopy, which was negative for esophagitis, and mucosal biopsies did not reveal eosinophilia. He was started on proton pump inhibitor (PPI) therapy and followed with a presumptive diagnosis of gastroesophageal reflux disease (GERD). The patient claims that his symptoms were initially better on the PPI, but have progressed over the last 3 months, and he has lost 10 lb.

In the office, his vital signs are stable and his body mass index is 27.8 kg/m2. His physical examination is otherwise normal, with no abnormalities on his heart and lung exams. Neurologically, he is intact, and there are no skin rashes or peripheral edema. He underwent an esophagram that revealed some minor bolus retention at 1 minute (barium column 8 cm), and his esophageal width at maximal diameter was 2.3 cm. Because the patient is continuing to have chest fullness and regurgitation despite PPI therapy and has an equivocal barium esophagram, he is scheduled to undergo a high-resolution manometry to rule out achalasia and rumination syndrome. Unfortunately, the patient is unable to tolerate the transnasal intubation due to a severe gag reflex and vomiting. Due to failure of manometry, the patient is scheduled for an endoscopy with Flip™ to rule out achalasia and assess his esophageal motility.

The catheter was placed transorally and positioned using measurement of the esophagogastric junction (EGJ) during endoscopy and checking the position with a bag infusion up to 20 mL. Once confident of positioning with the catheter placed through the EGJ and 2 to 3 sensors in the stomach, the controlled-volume distention protocol was performed in 10-mL increments, holding the volume for at least 20 seconds at each volume up to 70 mL. The data from the Flip™ are displayed on a topographic display of diameter changes over time and a 3-dimensional rendering of the Flip™ bag is displayed simultaneously, while pressure is recorded to generate a panometry diagnosis (Figure). Once the bag reaches 50 mL, there is some evidence of sporadic contractions that are not propagating in an ordered fashion. As the bag is infused to 60 mL, the maximal diameter reached through the EGJ is 9 mm, and this occurs with pressures greater than 60 mm Hg. The median EGJ distensibility index recorded is 0.8 mm/mm Hg and the contractions stop. Based on the impaired EGJ opening and uncoordinated motility, a diagnosis of achalasia is made and the patient is referred for a pneumatic dilation.


Figure. Flip™ technology and data output using a color scale for diameter.
The device is placed through the EGJ with 2 to 3 sensors into the stomach. Flip™ 1.0 provides real-time data on the diameters in a 3-dimensional geometry to illustrate the distensibility of the esophageal wall and EGJ. Contractions can be seen in red on the top of the recording segment in Flip™ 1.0 and the EGJ can be seen as an hourglass configuration. Flip™ 2.0 provides diameter topography similar to high-resolution manometry, and the axial length extends across the EGJ and into the stomach. Contractions are visualized as changes in diameter that move antegrade or retrograde up and down the esophagus. This is an example of normal motility and a normal EGJ opening.

EGJ, esophagogastric junction; Flip™, functional lumen imaging probe

Image courtesy of the Esophageal Center at Northwestern University.


The patient exhibits a pattern that is consistent with achalasia based on the contractile pattern and poor EGJ opening during Flip™. The contractile activity is not lumen occluding and likely would not be noted on manometry, but may be uncovered after therapy and would present as ineffective esophageal motility or extremely weak sporadic contractions. Thus, panometry may provide a more accurate depiction of achalasia subtypes, as illustrated in a recent paper by Carlson et al.3

If the Flip™ examination showed normal propagating contractions and a distensibility index greater than 3.0, achalasia would effectively have been ruled out and an alternative diagnosis would have been pursued.


  1. Pandolfino JE. The use of endoscopy and radiofrequency ablation for the treatment of GERD. Gastroenterol Hepatol (N Y). 2015;11(12):847-849.
  2. Varadarajulu S, Eloubeidi MA, Patel RS, et al. The yield and the predictors of esophageal pathology when upper endoscopy is used for the initial evaluation of dysphagia. Gastrointest Endosc. 2005;61(7):804-808.
  3. Carlson DA, Kahrilas PJ, Lin Z, et al. Evaluation of esophageal motility utilizing the functional lumen imaging probe. Am J Gastroenterol. 2016;111(12): 1726-1735.
  4. Pandolfino JE, de Ruigh A, Nicodème F, et al. Distensibility of the esophagogastric junction assessed with the functional lumen imaging probe (FLIP™) in achalasia patients. Neurogastroenterol Motil. 2013;25(6):496-501.