A review study to be submitted as a partial fulfillment of diploma in minimal access surgery World Laparoscopy Hospital. New Delhi

Done by Dr. Mohammad Shakir Huwaish Alkoubaisy
M.B.CH.B.FIBMS. DGS. D.MAS.
Rashid Hospital \General Surgery Department\ UAE. Dubai.

Abstract:

The aim of this retrospective Review was to compare the results of a 270° wrap (Toupet, T) versus360° wrap (Nissen, N) in patients with gastroesophageal reflux disease GERD). Nissen fundoplication is used frequently but may lead to postoperative bloating, inability to belch, and dysphagia. . Toupet has been known to be equally effective but associated with some unfavorable side effect. Both Nissen and Toupet wrapping offer an effective form of therapy for reflux disease with over 80% patient satisfaction.

Introduction :

In a fundoplication, the gastric fundus (upper part) of the stomach is wrapped, or plicated, around the inferior part of the esophagus, restoring the function of the lower esophageal sphincter. This prevents the reflux of gastric acid (in GERD) and/or the sliding of the fundus through the enlarged esophageal hiatus in the diaphragm. In a Nissen fundoplication, also called a complete fundoplication, the fundus is wrapped all the way around the esophagus. In a Toupet (posterior) fundoplication, the fundus is wrapped around the back of the esophagus.

The surgeon’s role has been increased in management of pathologic reflux because a laparoscopic surgery is more acceptable to patients than open surgery. Nissen (N) fundoplication is preferred by most surgeons around the world, probably because it is easy to teach and learn Special techniques has been placed on ensuring a “floppy wrap in all patients to minimize the incidence of postoperative dysphagia and gas bloating symptoms. Now recently the Toupet (T) procedure, a partial posterior 270° wrap, has been reported to be as effective as the 360° N procedure but associated with fewer postoperative problems The aim of this retrospective review was to compare both.

Material and Methods:

A review of 29 articles   concerning both Nissen and Toupet fundoplication was done using Google search and Springer link and High Wire Press and Medline and Cochrane library using the following search leads: Laparoscopic, total and partial fundoplicaton, Nissen versus Toupet fundoplication, comparisim, complications, and long term results. Criteria for selection of articles were:  Title, must be related to subject. Methodology; it must be a comparative study between partial and complete laparoscopic fundoplication. Randomized samples are preferred. Well recognized studies and articles were used. Especially recent studies were depended.

Results and Discussion:

The Nissen fundoplication is the most popular laparoscopic operation performed for the surgical treatment of gastro esophageal reflux disease (GERD). However, for patients in whom esophageal peristalsis is documented to be weak preoperatively, use of a partial wrap, or Toupet procedure, has often been used as an alternative to lessen the potential for postoperative dysphagia. Recent reports have criticized the Toupet procedure as having a higher long-term failure rate than the Nissen approach, especially for patients with severe forms of GERD. All procedures were performed at our institution by a single surgeon. Data recorded included preoperative demographic data, preoperative disease parameters, perioperative data, postoperative course, and symptom scores. Follow-up was based on a combination of medical records and phone interviews. There were 142 patients with complete records allowing review for this study. Of these, 118 underwent 122 Nissen fundoplications and 26 underwent 27 Toupet fundoplications. Selection of the procedure was based on preoperative manometric studies. There were seven reoperations. Seven of the patients (28%) who underwent Toupet procedures had severe GERD, a percentage comparable to the Nissen group (31.6%). Preoperative parameters were comparable for both groups, although the Toupet patients had lower average preoperative LES pressures (9.79 mmHg) than did the Nissen patients (16.1 mmHg, P < 0.05). The operative duration, operative blood loss, morbidity, length of hospitalization, need for reoperation, and efficacy in terms of relieving symptoms (average follow-up = 27.5 months) were comparable for both groups. Based on this experience, the Toupet procedure seems safe and effective in treating the symptoms of GERD, including patients with severe forms of the disease. We recommend its selective use in patients with preoperative esophageal hypo motility that is undergoing laparoscopic antireflux surgery [1]). In other study in same subject No significant differences between the operative groups were seen in heartburn, regurgitation or other reflux-related symptoms up to 1 year after surgery. Dysphagia of any degree (27 versus 9 per cent; P = 0·018) and chest pain on eating (22 versus 5 per cent; P = 0·018) were more prevalent at 1 year in the Nissen group. There were no differences in postoperative symptoms between the effective and ineffective motility groups. Surgery failed in eight patients on postoperative pH criteria, three in the Nissen group and five in the Toupet group. Any differences in the symptomatic outcome of laparoscopic Nissen and Toupet fundoplication appear minimal. There is no reason to tailor the degree of fundoplication to preoperative oesophageal manometry. [2] Two hundred patients with chronic GERD referred for laparoscopic fundoplication underwent clinical assessment, esophagogastroduodenoscopy, esophageal manometry, and 24-h pH monitoring. Patients were stratified according to presence or absence of esophageal dysmotility (100 in each group) and randomized to either a 360° (Nissen) or a 270° (Toupet) fundoplication. This resulted in 50 patients with normal motility and 50 patients with dysmotility undergoing Nissen fundoplications and Toupet fundoplications, respectively. Esophageal dysmotility was defined as primary peristalsis of ≤40% and/or mean distal esophageal pressure of <40 mm Hg. All preoperative tests were repeated 4 months postoperatively.

Pre-operative dysmotility was associated with more severe and medically refractory GERD with lower resting LES pressures than normal motility. Postoperative clinical outcome and reflux recurrence were similar and independent of preoperative motility. Reflux recurred in 14% of normal motility patients (four Toupet, 10 Nissen) and 21% of dysmotility patients (11 Toupet, 10 Nissen). Postoperative dysphagia was unrelated to preoperative esophageal motor function (30 normal motility, 31 dysmotility) but dependent on the type of fundoplication (44 Nissen and 17 Toupet patients developed dysphagia). Esophageal motility changed from pathological to normal in 10% and normal to pathological in 5%, with the remaining 85% unchanged. The authors concluded that esophageal dysmotility reflects more severe disease, does not affect postoperative clinical outcome, is not corrected by fundoplication, and requires no tailoring of the surgical procedure [3]. partial fundoplication has been proposed as technique to minimize the risk of side-effects following surgery for gastro-oesophageal reflux. We have applied this approach for the treatment of gastro-oesophageal reflux and/or large hiatus hernias. Previous studies have shown that this type of procedure can achieve good control of reflux, with fewer side-effects. However, only short-term follow up has been reported. In this study, we determined later clinical outcomes in patients who have undergone this procedure. All patients who underwent a laparoscopic anterior 90[degrees] partial fundoplication surgery were identified from a database, which collected prospective clinical data. Patients completed a standardized questionnaire 3 months after surgery and then yearly to assess clinical symptoms of reflux and postoperative side-effects. Between February 1999 and January 2006, 246 patients underwent surgery - 74 in conjunction with repair of a large hiatus hernia and 172 for reflux. Three patients underwent further surgery within 2 days of the original procedure (one for repair of a perforated oesophagus) and four underwent later surgical revision (reflux 3, dysphagia 1). Clinical follow-up data were available for 98% at 3-84 months (median 36). Most patients had effective relief of reflux symptoms at up to 3 years follow up. Dysphagia scores improved following surgery. The magnitude of this improvement was greater in patients with large hiatus hernias. More than 80% of the patients were able to belch normally at all time points after surgery and most were highly satisfied with the overall outcome. Satisfaction scores were higher following repair of a large hiatus hernia. The clinical results of laparoscopic anterior 90[degrees] fundoplication for either reflux or as part of repair of a large hiatus hernia are encouraging, although longer-term follow up is required to confirm durability of reflux control.Top of FormBottom of Form. Partial fundoplication has been proposed as technique to minimize the risk of side-effects following surgery for gastro-esophageal reflux. We have applied this approach for the treatment of gastro-esophageal reflux and/or large hiatus hernias. Previous studies have shown that this type of procedure can achieve good control of reflux, with fewer side-effects. However, only short-term follow up has been reported. In this study, we determined later clinical outcomes in patients who have undergone this procedure. All patients who underwent a laparoscopic anterior] partial fundoplication surgery were identified from a database, which collected prospective clinical data. Patients completed a standardized questionnaire 3 months after surgery and then yearly to assess clinical symptoms of reflux and postoperative side-effects. Between February 1999 and January 2006, 246 patients underwent surgery - 74 in conjunction with repair of a large hiatus hernia and 172 for reflux. Three patients underwent further surgery within 2 days of the original procedure (one for repair of a perforated esophagus) and four underwent later surgical revision (reflux 3, dysphagia 1). Clinical follow-up data were available for 98% at 3-84 months (median 36). Most patients had effective relief of reflux symptoms at up to 3 years follow up. Dysphagia scores improved following surgery. The magnitude of this improvement was greater in patients with large hiatus hernias. More than 80% of the patients were able to belch normally at all time points after surgery and most were highly satisfied with the overall outcome. Satisfaction scores were higher following repair of a large hiatus hernia. The clinical results of laparoscopic partial] fundoplication for either reflux or as part of repair of a large hiatus hernia are encouraging, although longer-term follow up is required to confirm durability of reflux control.[4].

The importance of the extent of the fundic wrap that encircles the distal esophagus for the establishment of long-term control of gastro-esophageal reflux disease (GORD) and for the risk of symptoms after fundoplication was evaluated in a prospective, randomized clinical trial. Of 137 consecutive patients with GORD, 72 were allocated to a semifundoplication (180-200 degrees, Toupet) and 65 to a total fundoplication (360 degrees, Nissen-Rossetti). Dysphagia was more common in the early postoperative period after a total fundic wrap, a difference which disappeared with time. This corresponded to a higher resting tone in the lower esophageal sphincter area. Seven patients (5 per cent) experienced relapse of GORD during follow-up of more than 3 years. Although no difference in the cumulative relapse rate (5 per cent for Nissen-Rossetti versus 6 per cent for Toupet) was found between the two study groups, the total failure rate was higher (P < 0.05) among patients who had a Nissen-Rossetti procedure because of a procedure-specific complication: intrathoracic herniation of the fundoplication in five patients caused obstructive symptoms without reflux (four had no posterior crural repair). In addition, symptoms in the form of flatulence were more frequently seen after Nissen-Rossetti fundoplication (P < 0.05 at 2 years and P < 0.01 at 3 years). Both Nissen-Rossetti and Toupet fundoplication equally well and durably controlled GERD. Fewer symptoms occurred in those having a semifundoplication, both in the early and late postoperative period [5]. Both Nissen and Toupet laparoscopic fundoplication can significantly improve patients' quality of life during the 5 years following surgical intervention. Quality of life scores for both surgical groups were almost equal and postoperative outcomes were comparable to values in healthy controls. Patient satisfaction with surgical treatment was very high, even though repeat laparoscopic surgery was necessary in some cases. Patients who had a repeat procedure experienced nearly identical outcomes [6]. For pediatric patients with GERD, laparoscopic Nissen, Toupet procedures yielded satisfactory results, and none of the approaches led to increased dysphagia. The 5% rate for intraoperative complications seems linked to the learning curve period. The authors consider the tow procedures as extremely effective for the treatment of children with GERD, and they believe that the choice of one procedure over the other depends only on the surgeon's experience [7].

Interviews showed that 88% (Nissen) and 90% (Toupet) of the patients, respectively, were satisfied with the operative result. Dysphagia was more frequent following a Nissen fundoplication than after a Toupet (30 vs. 11, p <0.001) and did not correlate with preoperative motility. In terms of reflux control, the Toupet proved to be as effective as the Nissen procedure [8]. Tailoring antireflux surgery according to the esophageal motility is not indicated, as motility disorders are not correlated with postoperative dysphagia. The Toupet procedure is the better operation as it has a lower rate of dysphagia and is as good as the Nissen fundoplication in controlling reflux [9]. In patients with severe GERD, laparoscopic Toupet and Rosetti-Nissen control symptoms and esophageal pH similarly. LES pressures are higher postop. in the Rosetti-Nissen. Dysphagia and gas-bloat are more prevalent in the Nissen group. Laparoscopic Toupet fundoplication may be superior to Rosetti-Nissen in reducing the frequency of side effects frequently associated with antireflux surgery, yet with equal control of reflux [10]. After two years 85% (Nissen) and 85% (Toupet) of patients were satisfied with the operative result. Dysphagia was more frequent following a Nissen fundoplication compared to Toupet (19 vs. 8, p < 0.05) and did not correlate with preoperative motility. Concerning reflux control the Toupet proved to be as good as the Nissen procedure (9) The results of my study do not differ significantly from the data reported in the literature, suggesting such surgical techniques are effective and well tolerated, and that both can be properly used in the treatment of GERD [11]. Comparable to the ones published in the world literature. In our hands, a Nissen fundoplication with complete mobilization of the fundus yielded the best results, a Nissen-Rossetti operation had more dysphagia and more reoperations and a partial fundoplication of Toupet, had a higher incidence of recurrent heartburn [12]. Concerns about laparoscopic antireflux surgery include the frequent appearance of troublesome postoperative dysphagia. This study reviews the frequency of early (less than 6 weeks) and persistent (greater than 6 weeks) solid food dysphagia in patients undergoing Toupet, Rosetti-Nissen, or Nissen fundoplications. Laparoscopic Rosetti-Nissen fundoplication is associated with a higher rate of early and persistent postoperative dysphagia than either laparoscopic Nissen fundoplication or Toupet fundoplication. Consideration of complete fundus mobilization should be a part of all laparoscopic antireflux procedures. [13]. Other study summarizes the experience with LT and LNF. Methods: Over a 45-month period (February 1995 to November 1998), 206 patients underwent laparoscopic antireflux operations. The LNF group included 163 patients and the LT group included 43 patients. Global quality of life was measured using the Medical outcomes short form 36 (SF36). Results: There were no differences in disease severity, except that the LT group had a higher incidence of esophageal dysmotility (37.2% 8.6%, p < 0.05). Early outcomes were similar, with no perioperative deaths and morbidity occurring in 15 (9.2%) LNF and 5 (11.6%) LT patients (p = not significant). Long-term follow-up was available in 142 patients at a mean of 19.7 months. A greater number of LT patients required proton pump inhibitors (38 vs 20%) and were dissatisfied (21 vs 7%) with their surgery (p < 0.05). SF36 physical function scores were better in the LNF group (85 vs 74; p < 0.05). Significantly more (p < 0.05) of the LT patients complained of dysphagia (34.5 vs 15%) on follow-up. There were no differences in the incidence of symptoms related to the gas-bloat syndrome. The observed differences between the LT and LNF groups did not appear to be related to differences in esophageal motility. Conclusions: Short-term results were similar for LT and LNF, but with longer follow-up, better results were seen with LNF. Even in the setting of moderate decreases of esophageal motility, complete fundoplication yields superior results [14.15].

Table 1 Preoperative demographical data for the two groups

Table 2 Pre- and postfundoplication results for the Nissen and Toupet groups

(t test, Mann–Whitney U test; p < 0.05)

Table 3 Patients with gas bloat syndrome post fundoplication

(Mann–Whitney U test; p = 0.05)

Table 4 patient satisfactions with the operation and medication usage postoperatively

(t test, Mann–Whitney U test; p < 0.05) Table 5 Quality-of-life questionnaire results

(t test, Mann–Whitney U test; p < 0.05)

Discussion

We consider the 60% response rate for the long-term follow-up questionnaire to be satisfactory, though not ideal considering the average long time period between surgery and the questionnaire in this review. Although some similar studies obtained better response results for shorter duration of follow-up, some obtained similar or poorer response rates with similar or longer duration of follow-up]. The mean postoperative follow-up time was 72 and 88 months for the Nissen and Toupet fundoplication groups, respectively. This difference is statistically significant and reflects the fact that more of the earlier procedures were partial fundoplications, as this was the practice of the more senior author (AC). No other preoperative demographical difference between the two groups reached a statistically significant difference apart from the ability to belch which was higher in the Toupet group (81% versus 61%)[15]. Although the results of the overall symptom questionnaire score for both groups was significantly improved after surgery, a statistical improvement in the heartburn and regurgitation scores was only detected in the Toupet group. However, in both groups the number of patients who had an improvement in the heartburn and regurgitation scores after surgery was statistically significant. This may imply that symptomatic patients in the Toupet group had fewer episodes of heartburn and regurgitation or milder symptoms preoperatively in comparison to symptomatic patients in the Nissen group. The postoperative results for both procedures show no statistical difference in overall symptoms score, GERD symptom specific scores, and the number of patients with regurgitation, dysphagia, nausea, waterbrash, hoarseness, and coughing. However, the number of patients with heartburn postoperatively was higher in the Nissen group. Fifty-six (57%) and 40 (65%) patients, in the Nissen and Toupet groups, respectively, complained of dysphagia preoperatively. This incidence is higher than that in the reported literature. It is not clear whether this high preoperative dysphagia rate is unique to this study population or whether it reflects the prospective and systematic evaluation of symptoms preoperatively done in this study. We strongly suspect the latter explanation. Forty-eight patients complained of dysphagia following a Nissen fundoplication. Of these, only eight patients complained of severe dysphagia (frequent, more than once a week and for solid, liquid or both). This incidence of severe dysphagia is similar to that reported for the series reviewed by Catarci et al. [16]. Twenty-two patients complained of dysphagia in the Toupet group after surgery, this being severe in six patients (8.9%). Several factors have been advocated to explain this complication, including the emotional state of the patient, surgical technical errors and intrinsic oesophageal dysmotility [17, 18]. None of these factors were evaluated in the present study. Thirty-three patients (33%) in the Nissen group and 23 patients (37.3%) in the Toupet group reported the development of untoward postoperative side-effects, the most frequent being early satiety and the gas bloat syndrome. All patients were made aware of the gas bloat syndrome during preoperative counselling and during the consent procedure [19]. The gas bloat syndrome incorporates the inability to belch and vomit as well as postprandial fullness (bloating). In this study, 25% and 13% of patients in the Nissen and Toupet group, respectively, had maintained the ability to belch. In the Nissen and the Toupet group 35% and 40% of patients were able to vomit, respectively. Early satiety was reported in 66% of patients following Nissen and in 74% of patients following Toupet fundoplication. Thus the gas bloat syndrome is common to both total and partial wraps. The incidence is thought to be higher in the initial period after surgery and to reduce progressively thereafter [20]. In the present study, the full-blown gas bloat syndrome was present in around 30% of patients seven years after surgery. In the Nissen and the Toupet group, 44% and 26% of patients, respectively, were using anti-acid/ acid suppression therapy 7 years after surgery. It is difficult to place too much emphasis on this finding. Often, medication intake is occasional and is not always effective in controlling the patient’s symptoms, which may not be reflux related [21. 22]. In the present study, 72% of patients in either group reported relief of perceived reflux symptoms after medication intake. The remaining 27–28% of patients did not achieve symptom relief by anti-acids or acid suppression medication. In the Nissen group 82% of patients, and in the Toupet group 83%, reported satisfaction with the overall result of surgery. An equivalent number of patients, 86% and 83.9%, in the Nissen and in the Toupet group, respectively, were sufficiently satisfied to recommend antireflux surgery to a friend or relative complaining of reflux symptoms. Two published studies have investigated patient satisfaction following antireflux surgery. Both Zornig [23] and Stewart [24] reported a similar degree of satisfaction following Nissen and Toupet fundoplications. Patient satisfaction is a reasonable and accurate tool to assess outcome after functional surgery especially when combined with other specific measures such as GERD-specific symptom scores and medication intake. When all these factors are taken into consideration, around 60% of patients in either the Nissen or Toupet groups were satisfied with the surgical procedure, have lower GERD-specific symptom scores, have not developed untoward side-effects, and have not had to recommence antacids or acid suppression therapy at 7 years follow-up. The short-term results of several randomized and nonrandomized clinical trials have shown that both the complete and partial wraps produce excellent symptoms control, and some of those studies showed a good objective control of reflux [23, 25, 26]. However, long-term results following laparoscopic antireflux procedure became available only recently and some doubts have been raised on the durability of partial wraps [27].

A technically successful antireflux procedure is not always a guarantee for the resolution of GERD symptoms, and indeed some patients may continue to experience reflux symptoms, indicating deterioration in individual functional status and general well-being following surgery [28]. Hence the importance of evaluating quality of life (QoL) following surgery for reflux disease. Equivalent QoL data were observed in the two surgical groups at 7 years in the present study. This study suffers from lack of objective evaluation of gastroesophageal reflux by pH-metry or endoscopy. This study however was focused on symptoms, patient satisfaction, and quality of life (QoL). We believe that symptom control and its effect on QoL is one of the primary objectives in antireflux surgery for the majority of patients. We also recognize shortcomings in different modalities of objective assessment of reflux particularly demonstrated by combined multichannel intraluminal impedance and pH-metry [29]. In conclusion, in patients who returned the questionnaire, long-term satisfaction, general symptom scores, and quality of life were equivalent after laparoscopic Nissen (complete) or Toupet (partial) fundoplication. There is however, a significant increased prevalence of persistent heartburn after laparoscopic Toupet fundoplication.

References:

1. laparoscopic Toupet versus Nissen fundoplication  for treatment of GERD .Int surg. 2003 OCT_DEC 88 (4) 219 _25
2. British Journal of surgery .volume 95 issue 1 page 57-63
3. American journal of gastroenterology. Volume97 issue 4 page 1056-1058 April 2002
4. ANZ Journal of surgery 78(3): 123-127, March 2008
5. Ann. Surgery 2000 224 (1) 51-7 867818
6. Endoscopy 2002 Nov. 34(11): 917-22
7. long term out come of laparoscopic NF, TF for neurologically normal chilidren with GERD.Endoscopy surgery June 20 (6) 855-8
8. Nissen versus Toupet fundoplicatin Surgical endoscopy 2002 May 16 (5) 758-66
9. NF versus TF 2 years out come of 200 patients study regarding pre operative esophagial motility.
10. Surger endoscopy 1996 10 (7); 742-8.
11. Laparoscopic anti reflux surgery comparative study. Endoscopsurgery 2000 Nov, 14 (11)1024-7.
12. Rev gastroenterol Mex .2005 Oct. –Dec, 70(4) 410-20.
13. Ann. Surgery 1997 July 226 (1) 109-110
14. Out come of laparoscopic TF versus NF. SURGICAL ENDOSCOPY. volume 16 No. 6 June 2002.
15. Long term comparitive out come between laparoscopic total NF and TF symptomes and pationt satisfactio n. and quality of life. surgical endocopy Volume 22 No. 4 April 2008.
16. Catarci M, Gentileschi P, Papi C, et al. (2004) Evidence-based appraisal of antireflux fundoplication. Ann Surg 239:325–337
17. Kamolz T, Granderath FA, Bammer T, et al. (2001) Psychological intervention influences the outcome of laparoscopic antireflux surgery in patients with stress-related symptoms of gastroesophageal reflux disease. Scand J Gastroenterol 36(8):800–805
18. Peters J (2001) Society of American Gastrointestinal Endoscopic Surgeons. SAGES Scientific session and postgraduate course, April 18–21, St Louis, Missouri
19. Anderson JR (2006) In: Griffin SM, Raimes SAA Oesophago-gastric surgery companion to specialist surgical practice. Elsevier Saunders, Philadelphia, pp 345–363
20. Kamolz T, Granderath FA, Pointner R, et al. (2002) Postprandial bloating after laparoscopic Nissen fundoplication: a cause of comorbidity? Can J Surg 45(4):306–307
21. Velanovich V (2003) Medication usage and additional esophageal procedures after antireflux surgery. Surg Laparosc Endosc Percutan Tech 13(3):161–164
22. Lord RV, Kaminski A, Oberg S, et al. (2002) Absence of gastroesophageal reflux disease in a majority of patients taking acid suppression medications after Nissen fundoplication. J Gastrointest Surg 6(1):3–9; discussion
23. Zornig C, Strate U, Emmermann A, et al. (2002) Nissen vs. Toupet laparoscopic fundoplication. Surg Endosc 16:758–766
24. Stewart GD, Watson AJ, Lamb PJ, et al. (2004) Comparison of three different procedures for antireflux surgery. Br J Surg 91(6):724–729
25. Laws HL, Clements RH, Swillie CM (1997) A randomized, prospective comparison of the Nissen fundoplication versus the Toupet fundoplication for gastroesophageal reflux disease. Ann Surg 225:647–654
26. Watson DI, Jamieson GG, Pike GK, et al. (1999) Prospective randomized double-blind trial between laparoscopic Nissen fundoplication and anterior partial fundoplication. Br J Surg 86:123–130
27. Khajanchee YS, O’Rourke RW, Lockhart B, et al. (2002) Postoperative symptoms and failure after antireflux surgery. Arch Surg 137(9):1008–1013; discussion 1013–1014
28. Kamolz T, Bammer T, Wykypiel H, et al. (2000) Quality of life and surgical outcome after laparoscopic Nissen and Toupet fundoplication: one-year follow-up. Endoscopy 32(5):363–368
29. Wise JL, Murray JA (2007) Utlising multichannel intraluminal impedance for diagnosing GERD: a review. Dis Esophagus 20:83–88