FROM CLINICAL GASTROENTEROLOGY AND HEPATOLOGY
New clinical practice advice has been issued for use of the functional lumen imaging probe (FLIP) to assess disorders of the upper gastrointestinal tract, with the main takeaway being the device’s potency in diagnosing achalasia.
“Although the strongest data appear to be focused on the management of achalasia, emerging evidence supports the clinical relevance of FLIP in the assessment of disease severity and as an outcome measure in [eosinophilic esophagitis (EoE)] intervention trials,” wrote the authors of the update, led by John E. Pandolfino, MD , of Northwestern University, Chicago. The report is in the March issue of Clinical Gastroenterology and Hepatology.
In reviewing relevant studies, Dr. Pandolfino and his coauthors found that FLIP is useful in determining esophagogastric junction (EGJ) function, mainly by allowing clinicians to more accurately evaluate the luminal opening to determine bolus flow. This could be more of a reliable diagnostic tool than simply using lower esophageal sphincter (LES) relaxation. One of the studies the authors reviewed, published in 2012 and led by Wout O. Rohof of the Academic Medical Center in Amsterdam, used an EndoFLIP to evaluate EGJ distensibility in healthy controls and patients with achalasia.
In terms of evaluating the LES, however, FLIP can be used during laparoscopic Heller myotomy or peroral endoscopic myotomy (POEM) as a way of monitoring the LES. Using FLIP this way can help clinicians and surgeons personalize the procedure to each patient, even while it’s ongoing. FLIP also can be used with dilation balloons, with the balloon diameter allowing dilation measurement without the need to also use fluoroscopy.
For treating gastroesophageal reflux disease (GERD), the evidence found in existing literature points with less certainty toward use of FLIP.
“The role of FLIP for physiologic evaluation and management in GERD remains appealing; however, the level of evidence is low and currently FLIP should not be used in routine GERD management,” the authors explained. “Future outcome studies are needed to substantiate the utility of FLIP in GERD and to develop metrics that predict severity and treatment response after antireflux procedures.”
FLIP can be used in managing eosinophilic esophagitis, but is recommended only in certain scenarios. According to the authors, FLIP can be used to measure esophageal narrowing and the overall esophageal body. FLIP also can be used to measure esophageal distensibility, and, in the case of at least one study reviewed by the authors, allows “significantly greater accuracy and precision in estimating the effects of remodeling” in certain patients.
Dr. Pandolfino and his colleagues warned that “current recommendations are limited by the low level of evidence and lack of generalized availability of the analysis paradigms.” They noted the need for “further outcome studies that validate the distensibility plateau threshold and further refinements in software analyses to make this methodology more generalizable.”
Overall, the authors concluded, more study still needs to be done to ascertain exactly what FLIP is capable of and when it can be used to greatest effect. In addition to evaluating its benefit in patients with GERD, research should focus on how to make data obtained via FLIP easier to interpret and put to use.
“More work is needed [that] focuses on optimizing data analysis, standardizing protocols, and defining outcome metrics prior to the widespread adoption [of FLIP] into general clinical practice,” the authors wrote.
Dr. Pandolfino disclosed relationships with Medtronic and Sandhill Scientific. Other coauthors did not report any relevant financial disclosures.