Indian J Gastroenterol DOI 10.1007/s12664-014-0529-0
LETTER
“EndoFLIP” in assessment of esophagogastric junction distensibility prior to and during per oral endoscopic myotomy Rakesh Kalapala & D. Nageshwar Reddy & Mohan Ramchandani & Santosh Darisetty
# Indian Society of Gastroenterology 2015
Sir, Achalasia cardia is a rare, irreversible motility disorder of the esophagus with an incidence of 1 in 100,000 per year [1]. The treatment options for achalasia include disruption of the lower esophageal sphincter (LES) by endoscopic pneumatic dilatation and surgical Heller’s myotomy. Recently, per oral endoscopic myotomy (POEM) has become the new modality of treatment which is an endoscopic alternative to surgical myotomy. POEM includes creation of a submucosal tunnel with subsequent myotomy of circular muscle layers [2]. The outcome and long-term prognosis of the treatment modalities are measured using esophageal manometry and timed barium esophagogram (TBE). Distensibility of the esophagogastric junction (EGJ) is a major factor to determine the efficacy and outcome of the treatment intraoperatively, especially in POEM. A more robust method for measuring EGJ distensibility providing cross-sectional area (CSA) measurements at adjacent segments without fluoroscopy adapts the principle of impedance planimetry into a functional luminal imaging probe (FLIP) (Table 1). Three adult treatment-naive patients with Type II achalasia cardia diagnosed with symptoms (Eckardt’s score), high resolution esophageal manometry (HREM), and TBE were subjected to POEM. EGJ distensibility was measured using a
R. Kalapala (*) : D. N. Reddy : M. Ramchandani : S. Darisetty Department of Medical Gastroenterology, Asian Institute of Gastroenterology, 6-3-661, Somajiguda, Hyderabad 500 082, India e-mail: [email protected]
commercially developed FLIP, the EndoFLIP probe (Crospon, Ireland) [3]. In this technique, a probe is inserted into the esophagus and placed at the level of the EGJ. The probe consists of a 240-cm catheter with a 14-cm bag attached to its distal end, which is compliant to a maximal diameter of 25 mm. Inside the bag, 17 electrodes are placed at 4-mm intervals. An excitation current of 100 A is generated between two adjacent electrodes at a frequency of 5 kHz. Using impedance planimetry, CSAs are determined for the 16 balloon cross sections during volume-controlled distensions. The distension probe and the pressure transducers were calibrated by the manufacturer. The pressure sensor was zeroed before insertion of the catheter, and subsequently the deflated catheter was inserted through orally by the side of endoscope. Manometry readings were used to position the balloon. In our distention protocol, the balloon was inflated to a 20-, 30-, 40-, and 50-mL volume. Pressures and CSAs are collected at a rate of 10 Hz. Distensibility was assessed using the median value over a 30-s dynamic measurement of the narrowest CSA, which corresponds to the EGJ, and the median intrabag pressures. The FLIP recordings allow the dynamic imaging of EGJ distension as a cylinder of varying diameter based on the instantaneous CSA measurements with concurrent pressure measurements. All three patients underwent classical POEM. EndoFLIP measurement was done pre and intraoperatively in these patients. An hourglass shape of the EndoFLIP bag was seen in all measurements preoperatively indicating the narrowest CSA at the level of LES. There was disappearance of hourglass waist in all the
Indian J Gastroenterol Table 1 Cross-sectional area values pre and intraoperative values prior to and during peroral endoscopic myotomy Subject (CSA in mm2)
20 mL
30 mL
40 mL
50 mL
1 2 3
18/50 44/90 12/44
20/60 48/94 14/49
22/61 50/98 16/50
23/70 56/104 18/54
CSA cross-sectional area
pneumatic dilatation, surgical myotomy, or POEM [4]. Evaluation of EGJ junction parameters is of great importance to know the posttreatment outcome and long-term need for re-treatments [5]. However, there are no tools to measure the intraoperative treatment success. EndoFLIP is one of its kind which helps to assess the adequacy of distensibility intraoperatively. In our series of three cases, all patients had adequate EGJ distensibility at the end of the procedure. The hourglass shape disappeared in all the patients, suggestive of improved distensibility. Hence, we hypothesize that assessment of EGJ distensibility intraoperatively will give the adequacy of therapeutic response of POEM which will eventually predict the short and long outcomes of the treatment response. We feel this technique is apt in routine clinical practice. However, the sample size is small and the long-term response of the treatment has to be assessed by a conglomeration of HREM, TBE, and EndoFLIP. This is the first case series reported from the Asia-Pacific region to the best of our knowledge (Fig. 2).
Fig. 1 EndoFLIP equipment with FLIP probe
References
subjects intraoperatively. The EGJ distensibility by CSA at 30 mL pre and postoperatively were 22/61, 50/98, and 16/ 50 mm2 with a diameter of 5.3/8/8, 8.4/11.3, and 4.5/ 10.6 mm, respectively (Fig. 1). Treatment of patients with achalasia cardia aims at relieving functional obstruction at the level of EGJ by disruption of the LES circular muscle fibers by endoscopic
1. Podas T, Eaden J, Mayberry M, Podas T, Eaden J, Mayberry M. Achalasia: a critical review of epidemiological studies. Am J Gastroenterol. 1998;93:2345–7. 2. Inoue H, Ikeda H, Hosoya T. Per-oral endoscopic myotomy (POEM) for esophageal achalasia [Japanese]. Nihon Shokakibyo Gakkai Zasshi. 2012;109:728–31. 3. McMahon BP, Frokjaer JB, Liao D, et al. A new technique for evaluating sphincter function in visceral organs: application of the functional lumen imaging probe (FLIP) for the evaluation of the oesophago-gastric junction. Physiol Meas. 2005;26:823–36.
Fig. 2 Pre and intraoperative disappearance of hourglass waist
Indian J Gastroenterol 4. Boeckxstaens GE, Annese V, Varannes SB. Pneumatic dilation versus laparoscopic Heller’s myotomy for idiopathic achalasia. N Engl J Med. 2011;364:1807–16.
5. Rohof WO, Hirsch DP, Kessing BF, et al. Efficacy of treatment for patients with achalasia depends on the distensibility of the esophagogastric junction. Gastroenterology. 2012;143:328–35.
LETTER
“EndoFLIP” in assessment of esophagogastric junction distensibility prior to and during per oral endoscopic myotomy Rakesh Kalapala & D. Nageshwar Reddy & Mohan Ramchandani & Santosh Darisetty
# Indian Society of Gastroenterology 2015
Sir, Achalasia cardia is a rare, irreversible motility disorder of the esophagus with an incidence of 1 in 100,000 per year [1]. The treatment options for achalasia include disruption of the lower esophageal sphincter (LES) by endoscopic pneumatic dilatation and surgical Heller’s myotomy. Recently, per oral endoscopic myotomy (POEM) has become the new modality of treatment which is an endoscopic alternative to surgical myotomy. POEM includes creation of a submucosal tunnel with subsequent myotomy of circular muscle layers [2]. The outcome and long-term prognosis of the treatment modalities are measured using esophageal manometry and timed barium esophagogram (TBE). Distensibility of the esophagogastric junction (EGJ) is a major factor to determine the efficacy and outcome of the treatment intraoperatively, especially in POEM. A more robust method for measuring EGJ distensibility providing cross-sectional area (CSA) measurements at adjacent segments without fluoroscopy adapts the principle of impedance planimetry into a functional luminal imaging probe (FLIP) (Table 1). Three adult treatment-naive patients with Type II achalasia cardia diagnosed with symptoms (Eckardt’s score), high resolution esophageal manometry (HREM), and TBE were subjected to POEM. EGJ distensibility was measured using a
R. Kalapala (*) : D. N. Reddy : M. Ramchandani : S. Darisetty Department of Medical Gastroenterology, Asian Institute of Gastroenterology, 6-3-661, Somajiguda, Hyderabad 500 082, India e-mail: [email protected]
commercially developed FLIP, the EndoFLIP probe (Crospon, Ireland) [3]. In this technique, a probe is inserted into the esophagus and placed at the level of the EGJ. The probe consists of a 240-cm catheter with a 14-cm bag attached to its distal end, which is compliant to a maximal diameter of 25 mm. Inside the bag, 17 electrodes are placed at 4-mm intervals. An excitation current of 100 A is generated between two adjacent electrodes at a frequency of 5 kHz. Using impedance planimetry, CSAs are determined for the 16 balloon cross sections during volume-controlled distensions. The distension probe and the pressure transducers were calibrated by the manufacturer. The pressure sensor was zeroed before insertion of the catheter, and subsequently the deflated catheter was inserted through orally by the side of endoscope. Manometry readings were used to position the balloon. In our distention protocol, the balloon was inflated to a 20-, 30-, 40-, and 50-mL volume. Pressures and CSAs are collected at a rate of 10 Hz. Distensibility was assessed using the median value over a 30-s dynamic measurement of the narrowest CSA, which corresponds to the EGJ, and the median intrabag pressures. The FLIP recordings allow the dynamic imaging of EGJ distension as a cylinder of varying diameter based on the instantaneous CSA measurements with concurrent pressure measurements. All three patients underwent classical POEM. EndoFLIP measurement was done pre and intraoperatively in these patients. An hourglass shape of the EndoFLIP bag was seen in all measurements preoperatively indicating the narrowest CSA at the level of LES. There was disappearance of hourglass waist in all the
Indian J Gastroenterol Table 1 Cross-sectional area values pre and intraoperative values prior to and during peroral endoscopic myotomy Subject (CSA in mm2)
20 mL
30 mL
40 mL
50 mL
1 2 3
18/50 44/90 12/44
20/60 48/94 14/49
22/61 50/98 16/50
23/70 56/104 18/54
CSA cross-sectional area
pneumatic dilatation, surgical myotomy, or POEM [4]. Evaluation of EGJ junction parameters is of great importance to know the posttreatment outcome and long-term need for re-treatments [5]. However, there are no tools to measure the intraoperative treatment success. EndoFLIP is one of its kind which helps to assess the adequacy of distensibility intraoperatively. In our series of three cases, all patients had adequate EGJ distensibility at the end of the procedure. The hourglass shape disappeared in all the patients, suggestive of improved distensibility. Hence, we hypothesize that assessment of EGJ distensibility intraoperatively will give the adequacy of therapeutic response of POEM which will eventually predict the short and long outcomes of the treatment response. We feel this technique is apt in routine clinical practice. However, the sample size is small and the long-term response of the treatment has to be assessed by a conglomeration of HREM, TBE, and EndoFLIP. This is the first case series reported from the Asia-Pacific region to the best of our knowledge (Fig. 2).
Fig. 1 EndoFLIP equipment with FLIP probe
References
subjects intraoperatively. The EGJ distensibility by CSA at 30 mL pre and postoperatively were 22/61, 50/98, and 16/ 50 mm2 with a diameter of 5.3/8/8, 8.4/11.3, and 4.5/ 10.6 mm, respectively (Fig. 1). Treatment of patients with achalasia cardia aims at relieving functional obstruction at the level of EGJ by disruption of the LES circular muscle fibers by endoscopic
1. Podas T, Eaden J, Mayberry M, Podas T, Eaden J, Mayberry M. Achalasia: a critical review of epidemiological studies. Am J Gastroenterol. 1998;93:2345–7. 2. Inoue H, Ikeda H, Hosoya T. Per-oral endoscopic myotomy (POEM) for esophageal achalasia [Japanese]. Nihon Shokakibyo Gakkai Zasshi. 2012;109:728–31. 3. McMahon BP, Frokjaer JB, Liao D, et al. A new technique for evaluating sphincter function in visceral organs: application of the functional lumen imaging probe (FLIP) for the evaluation of the oesophago-gastric junction. Physiol Meas. 2005;26:823–36.
Fig. 2 Pre and intraoperative disappearance of hourglass waist
Indian J Gastroenterol 4. Boeckxstaens GE, Annese V, Varannes SB. Pneumatic dilation versus laparoscopic Heller’s myotomy for idiopathic achalasia. N Engl J Med. 2011;364:1807–16.
5. Rohof WO, Hirsch DP, Kessing BF, et al. Efficacy of treatment for patients with achalasia depends on the distensibility of the esophagogastric junction. Gastroenterology. 2012;143:328–35.
