Comparison of the modern treatment methods for esophageal achalasia

Kaibysheva V.O.; Nikonov E.L.; Plakhov R.V.; Fedorov E.D.; Shapoval’yants S.G.

doi:https://doi.org/10.17116/dokgastro2019804-05144

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Abstract:

Aim. To analyze modern treatment methods for achalasia based on esophageal high-resolution manometry data. High-resolution manometry is the «gold standard» in the diagnosis of achalasia. In Chicago Classification of Esophageal Motility Disorders, achalasia divided into three clinically relevant subclasses based on the pattern of contractility in the esophageal body. Different types of esophageal motility disorders in patients with achalasia are essential to determine the prognosis of disease. The most favorable treatment outcomes are observed in patients with achalasia type II (96%). Treatment effectiveness of the patients with achalasia type I inversely correlates with severity of esophageal dilatation (81%). Traditional approaches (pneumocardial dilatation, Heller myotomy) with correction of the only lower esophageal sphincter in patients with achalasia type III are characterized by moderate efficiency (66%). Development of new methods of minimally invasive endoscopic treatment of achalasia (oral endoscopic myotomy) with myotomy length control significantly improved treatment of spastic achalasia (up to 92%). Conclusion. Esophageal high-resolution manometry in patients with suspected achalasia makes it possible to verify the diagnosis, determine the type of achalasia by the Chicago classification and choose the optimal treatment strategy. Oral endoscopic myotomy, balloon pneumocardial dilatation and Heller myotomy are preferred for achalasia type I and II, oral endoscopic myotomy — for achalasia type III and spastic syndromes (distal esophagospasm, hypercontractive esophagus). Botulinum toxin and drug therapy for achalasia have low efficacy, short-term effect and are indicated only for temporary relief of symptoms in preoperative period.

Keywords:

achalasia

esophagus

high-resolution manometry

oral endoscopic myotomy

Authors:

Kaibysheva V.O.

N.I. Pirogov Russian National Research Medical University, Moscow, Russia;
City Clinical Hospital №31, Moscow, Russia

ORCID: 0000-0003-0114-3700

Nikonov E.L.

FGBU "Poliklinika #1" Upravleniia delami Prezidenta RF

Scopus AuthorID: 57216680476
ResearcherID: T-9090-2017
ORCID: 0000-0003-3021-6534

Plakhov R.V.

Rossiĭskiĭ natsional'nyĭ issledovatel'skiĭ meditsinskiĭ universitet imeni N.I. Pirogova;
Gorodskaia klinicheskaia bol'nitsa #31, Moskva

Fedorov E.D.

Kafedra gospital'noĭ khirurgii #2 i nauchno-issledovatel'skaia laboratoriia khirurgicheskoĭ gastronterologii i ndoskopii Rossiĭskogo gosudarstvennogo meditsinskogo universiteta im. N.I. Pirogova

SPIN RSCI: 6785-9959
Scopus AuthorID: 7004381289
ORCID: 0000-0002-6036-7061

Shapoval’yants S.G.

Department of Hospital Surgery №2 with the research laboratory of surgical gastroenterology and endoscopy, N.I. Pirogov Russian National Research Medical University, Moscow

ORCID: 0000-0003-0629-3871

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References:

Pandolfino JE, Gawron AJ. Achalasia: a systematic review. JAMA. 2015;313(18):1841-1852. https://doi.org/10.1001/jama.2015.2996
Kahrilas PJ, Bredenoord AJ, Fox M, Gyawali CP, Roman S, Smout AJ, Pandolfino JE. International High Resolution Manometry Working Group. The Chicago Classification of esophageal motility disorders, v3.0. Neurogastroenterology and Motility. 2015;27(2):160-174. https://doi.org/10.1111/nmo.12477
Salvador R, Voltarel G, Savarino E, Capovilla G, Pesenti E, Perazzolo A, Nicoletti L, Costantini A, Merigliano S, Costantini M. The natural history of achalasia: Evidence of a continuum — «The evolutive pattern theory». Digestive and Liver Disease. 2018;50(4):342-347. https://doi.org/10.1016/j.dld.2017.11.012
Kaibysheva VO, Bredenoord AJ, Bordin DS, Morozov SV, Valitova ER, Fedorov ED, Isakov VA, Nikonov EL, Smirnov AA, Shapoval’yants SG. The technical aspects, interpretation of data, and clinical application of high-resolution esophageal manometry. Dokazatel’naya gastroenterologiya. 2018;7(2):28-49. https://doi.org/10.17116/dokgastro2018714-26
Wang YT, Tai LF, Yazaki E, Jafari J, Sweis R, Tucker E, Knowles K, Wright J, Ahmad S, Kasi M, Hamlett K, Fox MR, Sifrim D. Investigation of dysphagia after antireflux surgery by high-resolution manometry: impact of multiple water swallows and a solid test meal on diagnosis, management, and clinical outcome. Clinical Gastroenterology and Hepatology. 2015;13:1575-1583. https://doi.org/10.1016/j.cgh.2015.04.181
Burton PR, Brown W, Laurie C, Richards M, Afkari S, Yap K, Korin A, Hebbard G, O’Brien PE. The effect of laparoscopic adjustable gastric bands on esophageal motility and the gastroesophageal junction: analysis using high-resolution video manometry. Obesity Surgery. 2009;19:905-914. https://doi.org/10.1007/s11695-009-9845-3
Van Hoeij FB, Smout AJPM, Bredenoord AJ. Characterization of idiopathic esophagogastric junction outflow obstruction. Neurogastroenterology and Motility. 2015;27:1310-1316. https://doi.org/10.1111/nmo.12625
Pérez-Fernández MT, Santander C, Marinero A, Burgos-Santamaría D, Chavarría-Herbozo C.Characterization and follow-up of esophagogastric junction outflow obstruction detected by high resolution manometry. Neurogastroenterology and Motility. 2016;28:116-126. https://doi.org/10.1111/nmo.12708
Okeke FC, Raja S, Lynch KL, Dhalla S, Nandwani M, Stein EM, Chander Roland B, Khashab MA, Saxena P, Kumbhari V, Ahuja NK, Clarke J. What is the clinical significance of esophagogastric junction outflow obstruction? Evaluation of 60 patients at a tertiary referral center. Neurogastroenterology and Motility. 2017;29(6). https://doi.org/10.1111/nmo.13061
Schupack D, Katzka DA, Geno DM, Ravi K. The clinical significance of esophagogastric junction outflow obstruction and hypercontractile esophagus in high resolution esophageal manometry. Neurogastroenterology and Motility. 2017;29(10):1-9. https://doi.org/10.1111/nmo.13105
Ponds FA, Bredenoord AJ, Kessing BF, Smout AJ. Esophagogastric junction distensibility identifies achalasia subgroup with manometrically normal esophagogastric junction relaxation. Neurogastroenterology and Motility. 2017;29(1). https://doi.org/10.1111/nmo.12908
Kahrilas PJ, Bredenoord AJ, Fox M, Gyawali CP, Roman S, Smout AJPM, Pandolfino JE. International Working Group for Disorders of Gastrointestinal Motility and Function. Expert consensus document: Advances in the management of oesophageal motility disorders in the era of high-resolution manometry: a focus on achalasia syndromes. Nature Reviews. Gastroenterology and Hepatology. 2017;14(11):677-688. https://doi.org/10.1038/nrgastro.2017.132
Kahrilas PJ, Katzka D, Richter JE. Clinical Practice Update: The Use of Per-Oral Endoscopic Myotomy in Achalasia: Expert Review and Best Practice Advice from the American GastroenterologicalAssociation. Gastroenterology. 2017;1-7. https://doi.org/10.1053/j.gastro.2017.10.001
Kahrilas PJ, Pandolfino JE. Treatments for achalasia in 2017: how to choose among them. Current Opinion in Gastroenterology. 2017;33(4):270-276. https://doi.org/10.1097/MOG.0000000000000365
Sato H, Takahashi K, Mizuno KI, Hashimoto S, Yokoyama J, Hasegawa G, Terai S. Esophageal motility disorders: new perspectives from high-resolution manometry and histopathology. Journal of Gastroenterology. 2018;53(4):484-493. https://doi.org/10.1007/s00535-017-1413-3
Pandolfino JE, Kwiatek MA, Nealis T, Bulsiewicz W, Post J, Kahrilas PJ. Achalasia: a new clinically relevant classification by high-resolution manometry. Gastroenterology. 2008;135(5):1526-1533. https://doi.org/10.1053/j.gastro.2008.07.022
Farhoomand K, Connor JT, Richter JE, Achkar E, Vaezi MF.Predictors of outcome of pneumatic dilation in achalasia. Clinical Gastroenterology and Hepatology. 2004;2(5):389-394.
Pratap N, Reddy DN. Can achalasia subtyping by high-resolution manometry predict the therapeutic outcome of pneumatic balloon dilatation? author’s reply. Journal of Neurogastroenterology and Motility. 2011;17(2):205. https://doi.org/10.5056/jnm.2011.17.2.205
Richards WO, Torquati A, Holzman MD, Khaitan L, Byrne D, Lutfi R, Sharp KW. Heller myotomy versus Heller myotomy with Dor fundoplication for achalasia: a prospective randomized double-blind clinical trial. Annals of Surgery. 2004;240(3):405-412. https://doi.org/10.1007/s00464-017-5845-x
Rebecchi F, Giaccone C, Farinella E, Campaci R, Morino M. Randomized controlled trial of laparoscopic Heller myotomy plus Dor fundoplication versus Nissen fundoplication for achalasia: long-term results. Annals of Surgery. 2008;248(6):1023-1030. https://doi.org/10.1097/SLA.0b013e318190a776
Rawlings A, Soper NJ, Oelschlager B, Swanstrom L, Matthews BD, Pellegrini C, Pierce RA, Pryor A, Martin V, Frisella MM, Cassera M, Brunt L. Laparoscopic Dor versus Toupet fundoplication following Heller myotomy for achalasia: results of a multicenter, prospective, randomized-controlled trial. Surgical Endoscopy. 2012;26(1):18-26. https://doi.org/10.1007/s00464-011-1822-y
Boeckxstaens GE, Annese V, des Varannes SB, Chaussade S, Costantini M, Cuttitta A, Elizalde JI, Fumagalli U, Gaudric M, Rohof WO, Smout AJ, Tack J, Zwinderman AH, Zaninotto G, Busch OR. Pneumatic dilation versus laparoscopic Heller’s myotomy for idiopathic achalasia. New England Journal of Medicine. 2011;364:1807-1816. https://doi.org/10.1056/NEJMoa1010502
Moonen A, Annese V, Belmans A, Bredenoord AJ, Bruley des Varannes S,Costantini M, Dousset B, Elizalde JI, Fumagalli U, Gaudric M, Merla A, Smout AJ, Tack J, Zaninotto G, Busch OR, Boeckxstaens G. Long-term results of the European achalasia trial: a multicenter randomised controlled trial comparing pneumatic dilation versus laparoscopic Heller myotomy. Gut. 2016;65:732-739. https://doi.org/10.1136/gutjnl-2015-310602
Lynch KL, Pandolfino JE, Howden CW, Kahrilas P. Major complications of pneumatic dilation and Heller myotomy for achalasia: single-center experience and systematic review of the literature. American Journal of Gastroenterology. 2012;107(12):1817-1825. https://doi.org/10.1038/ajg.2012.332
Kostic S, Johnsson E, Kjellin A, Ruth M, Lönroth H, Andersson M, Lundell L. Health economic evaluation of therapeutic strategies in patients with idiopathic achalasia: results of a randomized trial comparing pneumatic dilatation with laparoscopic cardiomyotomy. Surgical Endoscopy. 2007;21(7):1184-1189.
Novais PA, Lemme EMO. 24-h pH monitoring patterns and clinical response after achalasia treatment with pneumatic dilation or laparoscopic Heller myotomy. Alimentary Pharmacology and Therapeutics. 2010;32(10):1257-1265. https://doi.org/10.1111/j.1365-2036.2010.04461.x
Persson J, Johnsson E, Kostic S, Lundell L, Smedh U. Treatment of achalasia with laparoscopic myotomy or pneumatic dilatation: long-term results of a prospective, randomized study. World Journal of Surgery. 2015;39(3):713-720. https://doi.org/10.1007/s00268-014-2869-4
Bakhshipour A, Rabbani R, Shirani S, Soleimani HA, Mikaeli J. Comparison of pneumatic dilation with pneumatic dilation plus botulinum toxin for treatment of achalasia. Acta Medica Iranica. 2010;48(2):107-110.
Inoue H, Sato H, Ikeda H, Onimaru M, Sato C, Minami H, Yokomichi H, Kobayashi Y, Grimes KL, Kudo SE. Per-oral endoscopic myotomy: a series of 500 patients. Journal of the American College of Surgeons. 2015;221:256-264. https://doi.org/10.1016/j.jamcollsurg.2015.03.057
Ponds FA, Fockens P, Lei A, Neuhaus H, Beyna T, Kandler J, Frieling T, Chiu PWY, Wu JCY, Wong VWY, Costamagna G, Familiari P, Kahrilas PJ, Pandolfino JE, Smout AJPM, Bredenoord AJ. Effect of Peroral Endoscopic Myotomy vs Pneumatic Dilation on Symptom Severity and Treatment Outcomes among Treatment-NaivePatients with Achalasia: A Randomized Clinical Trial. JAMA. 2019;322(2):134-144. https://doi.org/10.1001/jama.2019.8859
Bhayani NH, Kurian AA, Dunst CM, Sharata AM, Rieder E, Swanstrom LL. A comparative study on comprehensive, objective outcomes of laparoscopic Heller myotomy with per-oral endoscopic myotomy (POEM) for achalasia. Annals of Surgery. 2014;259(6):1098-1103. https://doi.org/10.1097/SLA.0000000000000268
Chan SM, Wu JC, Teoh AY, Yip HC, Ng EK, Lau JY, Chiu PW. Comparison of early outcomes and quality of life after laparoscopic Heller’s cardiomyotomy to peroral endoscopic myotomy for treatment of achalasia. Digestive Endoscopy. 2016;28:27-32. https://doi.org/10.1111/den.12507
Kumbhari V, Tieu AH, Onimaru M. Peroral endoscopic myotomy (POEM) vs laparoscopic Heller myotomy (LHM) for the treatment of Type III achalasia in 75 patients: a multicenter comparative study. Endoscopy International Open. 2015;3:195-201. https://doi.org/10.1055/s-0034-1391668
Schneider AM, Louie BE, Warren HF, Farivar AS, Schembre DB, Aye RW. A matched comparison of per oral endoscopic myotomy to laparoscopic Heller myotomy in the treatment of achalasia. Journal of Gastrointestinal Surgery. 2016;20:1789-1796. https://doi.org/10.1007/s11605-016-3232-x
Teitelbaum EN, Rajeswaran S, Zhang R, Sieberg RT, Miller FH, Soper NJ, Hungness ES. Peroral esophageal myotomy (POEM) and laparoscopic Heller myotomy produce a similar short-term anatomic and functional effect. Surgery. 2013;154:885-891. https://doi.org/10.1016/j.surg.2013.04.051
Cai MY, Zhou PH, Yao LQ, Xu MD, Zhong YS,Li QL, Chen WF, Hu JW, Cui Z, Zhu. Peroral endoscopic myotomy for idiopathic achalasia: randomized comparison of water-jet assisted versus conventional dissection technique. Surgical Endoscopy. 2014;28:1158-1165. https://doi.org/10.1007/s00464-013-3300-1
Familiari P, Gigante G, Marchese M, Boskoski I, Tringali A, Perri V, Costamagna G. Peroral endoscopic myotomy for esophageal achalasia: outcomes of the first 100 patients with short-term follow-up. Annals of Surgery. 2016;263:82-87. https://doi.org/10.1097/SLA.0000000000000992
Hungness ES, Sternbach JM, Teitelbaum EN, Kahrilas PJ, Pandolfino JE, Soper NJ. Peroral endoscopic myotomy (POEM) after the learning curve: durable long-term results with a low complication rate. Annals of Surgery. 2016;264:508-517. https://doi.org/10.1097/SLA.0000000000001870
Kumbhari V, Familiari P, Bjerregaard NC, Pioche M, Jones E, Ko WJ, Hayee B, Cali A, Ngamruengphong S, Mion F, Hernaez R, Roman S, Tieu AH, El Zein M, Ajayi T, Haji A, Cho JY, Hazey J, Perry KA, Ponchon T, Kunda R, Costamagna G, Khashab MA. Gastroesophageal reflux after peroral endoscopic myotomy: a multicenter case-control study. Endoscopy. 2017;49:634-642. https://doi.org/10.1055/s-0043-105485
Ngamruengphong S, Inoue H, Chiu PW, Yip HC, Bapaye A, Ujiki M, Patel L, Desai PN, Hayee B, Haji A, Wong VW, Perretta S, Dorwat S, Pioche M, Roman S, Rivory J, Mion F, Ponchon T, Garros A, Nakamura J, Hata Y, Balassone V, Onimaru M, HajiyevaG, Ismail A, Chen YI, Bukhari M, Haito-Chavez Y, Kumbhari V, Maselli R, Repici A, Khashab M. Long-term outcomes of per-oral endoscopic myotomy in patients with achalasia with a minimum follow-up of 2 years: an international multicenter study. Gastrointestinal Endoscopy. 2017;85:927-933. https://doi.org/10.1016/j.gie.2016.09.017
Ramchandani M, Nageshwar Reddy D, Darisetty S, Kotla R, Chavan R, Kalpala R,Galasso D, Lakhtakia S, Rao GV. Peroral endoscopic myotomy for achalasia cardia: treatment analysis and follow up of over 200 consecutive patients at a single center. Digestive Endoscopy. 2016;28:19-26. https://doi.org/10.1111/den.12495
Orenstein SB, Raigani S, Wu YV, Pauli EM, Phillips MS, Ponsky JL, Marks JM. Peroral endoscopic myotomy (POEM) leads to similar results in patients with and without prior endoscopic or surgical therapy. Surgical Endoscopy. 2015;29:1064-1070. https://doi.org/10.1007/s00464-014-3782-5
Ngamruengphong S, Inoue H, Ujiki MB, Patel LY, Bapaye A, Desai PN, Dorwat S, Nakamura J, Hata Y, Balassone V, Onimaru M, Ponchon T, Pioche M, Roman S, Rivory J, Mion F, Garros A, Draganov PV, Perbtani Y, Abbas A, Pannu D, Yang D, Perretta S, Romanelli J, Desilets D, Hayee B, Haji A, Hajiyeva G, Ismail A, Chen YI, Bukhari M, Haito-Chavez Y, Kumbhari V, Saxena P, Talbot M, Chiu PW, Yip HC, Wong VW, Hernaez R, Maselli R, Repici A, Khashab MA. Efficacy and safety of peroral endoscopic myotomy for treatment of achalasia after failed Heller myotomy. Clinical Gastroenterology and Hepatology. 2017;15:1531-1537. https://doi.org/10.1016/j.cgh.2017.01.031
Schlottmann F, Luckett DJ, Fine J, Shaheen NJ, Patti MG. Laparoscopic Heller myotomy versus peroral endoscopic myotomy (POEM) for achalasia: a systematic review and metaanalysis. Annals of Surgery. 2018;267(3):451-460. https://doi.org/10.1097/SLA.0000000000002311
Werner YB, Costamagna G, Swanström LL, von Renteln D, Familiari P, Sharata AM,Noder T, Schachschal G, Kersten JF, Rösch T. Clinical response to peroral endoscopic myotomy in patients with idiopathic achalasia at a minimum follow-up of 2 years. Gut. 2016;65:899-906. https://doi.org/10.1136/gutjnl-2014-308649
Rösch T, Repici A, Boeckxstaens G. Will reflux kill POEM? Endoscopy. 2017;49:625-628. https://doi.org/10.1055/s-0043-112490
Kurian AA, Dunst CM, Sharata A, Bhayani NH, Reavis KM, Swanström L. Peroral endoscopic esophageal myotomy: defining the learning curve. Gastrointestinal Endoscopy. 2013;77:719-725. https://doi.org/10.1016/j.gie.2012.12.006
Patel KS, Calixte R, Modayil RJ, Friedel D, Brathwaite CE, Stavropoulos SN. The light at the end of the tunnel: a single-operator learning curve analysis forperoral endoscopic myotomy. Gastrointestinal Endoscopy. 2015;81:1181-1187. https://doi.org/10.1016/j.gie.2014.10.002
Rohof WO, Salvador R, Annese V, Bruley des Varannes S, Chaussade S, Costantini M, Elizalde JI, Gaudric M, Smout AJ, Tack J, Busch OR, Zaninotto G, Boeckxstaens GE. Outcomes of treatment for achalasia depend on manometric subtype. Gastroenterology. 2013;144(4):718-725. https://doi.org/10.1053/j.gastro.2012.12.027
Pratap N, Kalapala R, Darisetty S, Joshi N, Ramchandani M, Banerjee R,Lakhtakia S, Gupta R, Tandan M, Rao GV, Reddy DN. Achalasia cardia subtyping by high-resolution manometry predicts the therapeutic outcome of pneumatic balloon dilatation. Journal of Neurogastroenterology and Motility. 2011;17:48-53. https://doi.org/10.5056/jnm.2011.17.1.48
Salvador R, Costantini M, Zaninotto G, Morbin T, Rizzetto C, Zanatta L, Ceolin M, Finotti E, Nicoletti L, Da Dalt G, Cavallin F, Ancona E. The preoperative manometric pattern predicts the outcome of surgical treatment for esophageal achalasia. Journal of Gastrointestinal Surgery. 2010;14(11):1635-1645. https://doi.org/10.1007/s11605-010-1318-4
Khan MA, Kumbhari V, Ngamruengphong S, Ismail A, Chen YI, Chavez YH, Bukhari M, Nollan R, Ismail MK, Onimaru M, Balassone V, Sharata A, Swanstrom L, Inoue H, Repici A, Khashab MA. Is POEM the Answer for Management of Spastic Esophageal Disorders? A Systematic Review and Metaanalysis. Digestive Diseases and Sciences. 2017;62(1):35-44. https://doi.org/10.1007/s10620-016-4373-1
Duan T, Tan Y, Zhou J, Lv L, Liu D. A Retrospective Study of Peroral Endoscopic Full-Thickness Myotomy in Patients with Severe Achalasia. Journal of Laparoendoscopic and Advanced Surgical Techniques. Part A. 2017;27(8):770-776. https://doi.org/10.1089/lap.2016.0445
Haito-Chavez Y, Inoue H, Beard KW, Draganov PV, Ujiki M, Rahden BHA, Desai PN, Pioche M, Hayee B, Haji A, Saxena P, Reavis K, Onimaru M, Balassone V, Nakamura J, Hata Y, Yang D, Pannu D, Abbas A, Perbtani YB, Patel LY, Filser J, Roman S, Rivory J, Mion F, Ponchon T, Perretta S, Wong V, Maselli R, Ngamruengphong S, Chen YI, Bukhari M, Hajiyeva G, Ismail A, Pieratti R, Kumbhari V, Galdos-Cardenas G, Repici A, Khashab MA. Comprehensive Analysis of Adverse Events Associated With Per Oral Endoscopic Myotomy in 1826 Patients: An International Multicenter Study. American Journal of Gastroenterology. 2017;112(8):1267-1276. https://doi.org/10.1038/ajg.2017.139
Pasricha PJ, Rai R, Ravich WJ, Hendrix TR, Kalloo AN. Botulinum toxin for achalasia: long-term outcome and predictors of response. Gastroenterology. 1996;110(5):1410-1415.
Annese V. GISMAD Achalasia Study Group. A multicentre randomized study of intrasphincteric botulinum toxin in patients with oesophageal achalasia. Gut. 2000;46:597-600.
Vaezi MF, Richter JE, Wilcox CM, Schroeder PL, Birgisson S, Slaughter RL, Koehler RE, Baker ME. Botulinum toxin versus pneumatic dilatation in the treatment of achalasia: a randomised trial. Gut. 1999;44(2):231-239.
Zaninotto G, Annese V, Costantini M, Del Genio A, Costantino M, Epifani M, Gatto G, D’onofrio V, Benini L, Contini S, Molena D, Battaglia G, Tardio B, Andriulli A, Ancona E. Randomized controlled trial of botulinum toxin versus laparoscopic heller myotomy for esophageal achalasia. Annals of Surgery. 2004;239(3):364-370.
Gelfond M, Rozen P, Gilat T. Isosorbide dinitrate and nifedipine treatment of achalasia: a clinical, manometric and radionuclide evaluation. Gastroenterology. 1982;83:963-969.
Bortolotti M, Mari C, Lopilato C, Porrazzo G, Miglioli M. Effects of sildenafil on esophageal motility of patients with idiopathic achalasia. Gastroenterology. 2000;118(2):253-257.
Hirano I, Tatum RP, Shi G, Sang Q, Joehl RJ, Kahrilas PJ. Manometric heterogeneity in patients with idiopathic achalasia. Gastroenterology. 2001;120(4):789-798.
Mittal RK, Ren J, McCallum RW, Shaffer HA Jr, Sluss J. Modulation of feline esophageal contractions by bolus volume and outflow obstruction. American Journal of Physiology.1990;258 (2 Pt 1):G208-G215.
Schneider JH, Peters JH, Kirkman E, Bremner CG, DeMeester TR. Are the motility abnormalities of achalasia reversible? An experimental outflow obstruction in the feline model. Surgery. 1999;125(5):498-503.
Cruiziat C, Roman S, Robert M, Espalieu P, Laville M, Poncet G, Gouillat C, Mion F. High resolution esophageal manometry evaluation in symptomatic patients after gastric banding for morbid obesity. Digestive and Liver Disease. 2011;43(2):116-120. https://doi.org/10.1016/j.dld.2010.08.011
Khan A, Ren-Fielding C, Traube M. Potentially reversible pseudoachalasia after laparoscopic adjustable gastric banding. Journal of Clinical Gastroenterology. 2011;45(9):775-779. https://doi.org/10.1097/MCG.0b013e318226ae14
Goldblum JR, Rice TW, Richter JE. Histopathologic features in esophagomyotomy specimens from patients with achalasia. Gastroenterology. 1996;111(3):648-654.
Sodikoff JB, Lo AA, Shetuni BB, Kahrilas PJ, Yang GY, Pandolfino JE. Histopathologic patterns among achalasia subtypes. Neurogastroenterology and Motility. 2016;28(1):139-145. https://doi.org/10.1111/nmo.12711
Carlson DA, Lin Z, Kahrilas PJ, Sternbach J, Donnan EN, Friesen L, Listernick Z, Mogni B, Pandolfino JE. The Functional Lumen Imaging Probe Detects Esophageal Contractility not Observed with Manometry in Patients with Achalasia. Gastroenterology. 2015;149(7):1742-1751. https://doi.org/10.1053/j.gastro.2015.08.005