Esophagus DOI 10.1007/s10388-013-0395-3
ORIGINAL ARTICLE
Surgical treatment for Zenker’s diverticulum: comparison between diverticulectomy and diverticulopexy Francesco Puma • Jacopo Vannucci • Claudio Fioroni • Elisa Scarnecchia • Verena De Angelis • Nicola Avenia • Mark Ragusa • Giuliano Daddi
Received: 24 April 2013 / Accepted: 13 August 2013 Ó The Japan Esophageal Society and Springer Japan 2013
Abstract Background The ideal surgical technique for symptomatic Zenker’s diverticulum has not been identified yet. Endoscopic treatment, although frequently performed, has not replaced the open cricopharyngeal myotomy, which is still deemed the standard therapy by many dedicated physicians. The management of the diverticular sac after myotomy is still a matter of debate. The aim of this study is to compare the results of diverticulectomy and diverticulopexy after cricopharyngeal myotomy, in homogeneous groups of patients. Methods Thirty-seven patients were treated for Zenker’s diverticulum at the same university medical school, but in two different units, with open cricopharyngeal myotomy, associated with diverticulectomy in 17 patients and with diverticulopexy in the remaining. No clinical criteria influenced the different choice of treatment of the diverticular pouch, but only the surgeon’s preference. Clinical data, diverticulum size, postoperative course, and
F. Puma (&) J. Vannucci E. Scarnecchia M. Ragusa G. Daddi Thoracic Surgery Unit, University of Perugia Medical School, Loc. Sant’ Andrea delle Fratte, 06134 Perugia, Italy e-mail:
[email protected] C. Fioroni Section of Diagnostic and Interventional Radiology, Santa Maria della Misericordia, Perugia, Italy V. De Angelis Department of Oncologic, Hematologic and Gastroenterological Sciences, University of Perugia Medical School, Perugia, Italy N. Avenia Endocrine Surgery of Neck and Soft Tissues Unit, University of Perugia Medical School, Perugia, Italy
complications were analyzed. Patients were followed up for median duration of 37 months (range 12–113 months) through contrast swallow study and clinical evaluation, aided by a specifically conceived questionnaire. Records were analyzed by Mann–Whitney–Wilcoxon test and Fisher’s exact test. Results Homogeneous comparative values for sex, age, diverticulum size, and symptoms were found in the two groups. Statistical analysis indicated that diverticulopexy, as compared with diverticulectomy, allowed reduced postoperative complications and slightly improved longterm swallowing. Conclusions Diverticulopexy is feasible also in large Zenker’s diverticula and can achieve equivalent or even better results than diverticulectomy with a smoother postoperative course. Keywords Esophagus Benign disease Esophageal surgery Operations Esophageal motility disorders
Introduction Zenker’s diverticulum (ZD) is an acquired mucosa outpouching, occurring at the level of the posterior wall of the hypopharynx, just above the cricopharyngeal muscle. Uncoordinated contraction/relaxation of cricopharyngeal muscle is responsible for the pathophysiology of ZD. There is no codified medical treatment, and surgery is the most pervasive therapeutic option, although it is only palliative. Several studies have compared different open and endoscopic treatments of ZD, but the technique of choice has still not been identified [1–4]. Both open surgical and endoscopic techniques are based on cricopharyngeal
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myotomy, which has been recognized as the key factor for effective cure [5]. Endoscopic procedures may be favored for the absence of skin incision and for decreased surgical trauma, operative time, and hospital stay [1, 5–7]. Those authors who prefer open surgery deem that this approach allows more reliable cricopharyngeal myotomy and, therefore, results in a lower long-term failure rate [2, 8]. The treatment of the diverticular pouch after open cricopharyngeal myotomy is a matter of choice: it can be left in place, invaginated, suspended (diverticulopexy) or resected (diverticulectomy). Diverticulectomy and diverticulopexy are the most frequently performed open techniques, and their selection is primarily influenced by ZD size and surgeon preference. The aim of this study is to compare the results of diverticulectomy and diverticulopexy, after transcervical cricopharyngeal myotomy, in homogeneous groups of patients.
Patients and methods Thirty-seven consecutive symptomatic patients underwent left cervicotomy for ZD at the two thoracic surgery units of the University of Perugia Medical School, between 2002 and 2011: 17 underwent cricopharyngeal myotomy and diverticulectomy (group A), and 20 underwent cricopharyngeal myotomy and diverticulopexy (group B). The choice between diverticulectomy and diverticulopexy was made by each single surgeon involved in the study, only on the basis of his/her own preference for one of the two techniques; i.e., patients’ clinical data and features of diverticula had no influence on the choice of treatment of the diverticular sac after myotomy. Clinical and surgical records were retrospectively reviewed and all patients followed up for at least 12 months. The patient’s medical history and barium swallow studies were used to determine whether surgery was indicated. Computed tomography, esophagoscopy, and esophageal functional studies were not routinely used. After diagnosis, the preoperative workup was always completed by electrocardiograph, chest X-ray, complete blood count, and anesthesiological assessment. Diverticulum size was evaluated by revision of the last available preoperative contrast swallow study to calculate the maximum diameter of the pouch. All operations were carried out through a 6–8 cm longitudinal left cervical incision. Diverticulum wall dissection was performed first; no accidental tearing of the diverticulum wall occurred during the procedures. Gentle rotation of the larynx towards the right side allowed the posterior myotomy, to minimize the risk of left laryngeal nerve injury. The technique of myotomy was identical in the two groups: magnification with surgical
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loupes was used in all procedures to achieve section of all cricopharyngeal fibers and 2–3 cm of the proximal esophagus. Since 2007, when we planned to conduct a study on this topic, we started to record the intraoperative diverticulum size, calculating the transverse diameter and the distance from the bottom to the neck of the sac. In group A, diverticulectomies were carried out at the level of the diverticular neck using a linear stapler loaded with 2.5 mm staples (no bougies were routinely used to calibrate the esophageal lumen while stapling; Fig. 1a). The suture was tested under water for airtightness by insufflating 50–100 ml of air through the nasogastric tube, which had previously been withdrawn to the cervical level. In group B, the bottom of the diverticulum was fixed superiorly to the prevertebral fascia, using 4–0 nonabsorbable monofilament stitches (Fig. 1b). At the end of the procedure, a closed-suction drain was positioned and the nasogastric tube removed in both groups. Myotomy was performed ‘‘under direct view,’’ and no supportive tools such as manometry were employed. Because of the different clinical habits between the two surgical units regarding refeeding and need for postoperative radiographic controls, data concerning length of hospital stay and time to oral intake resumption were considered not homogeneous and unsuitable for comparative analysis. Anyway, all patients of group B resumed oral feeding immediately after surgery, compared with none in group A, who restarted solid oral diet between day 4 and 6, after a contrast esophagogram. To evaluate the anatomical outcome of the two procedures, a Gastromiro swallow test (Bracco SpA, Milan, Italy) was performed at a minimum of 12 months after surgery. The medical condition of the patients was evaluated by a specifically conceived questionnaire, designed to assess: quality and duration of palliation, pre- and postoperative level of dysphagia, other possible symptoms, and
Fig. 1 a Diverticulectomy. b Diverticulopexy
Esophagus
nutritional and health status. Pre- and postoperative subjective feeling of swallowing were expressed on a percentage scale ranging from 0 % (impossible oral intake) to 100 % (absolutely normal swallowing). Gastromiro swallow tests were examined by a radiologist (C.F.), blinded to the procedure conducted. The data were collected (IBMÒ) and analyzed retrospectively (with use of SPSS software, version 15.0). Fisher’s exact test or the Mantel–Haenszel chi-square statistic was used for categorical variables, and the Mann– Whitney–Wilcoxon rank-sum test was used for continuous variables. p-Value \0.05 was considered statistically significant.
In group A (diverticulectomy), two patients had minimal suture leakage, occurring 7 and 11 days after surgery. In both cases the postoperative contrast esophagogram failed to identify the complication, which became evident only after refeeding. Both patients healed spontaneously with a percutaneous cervical drain and a short period of total parenteral nutrition. Another two patients experienced transient minor complications, both of which resolved without specific treatment: one Claude Bernard–Horner syndrome and one left vocal cord palsy. In group B (diverticulopexy), all patients had an uneventful postoperative course. Follow-up
Results Epidemiological and clinical data Group A included 11 men and 6 women with age ranging from 48 to 90 years [median (Me) 66 years]. Group B included 18 men and 2 women between 52 and 86 years old (Me 69.5 years). Nearly constant clinical features were found: cervical dysphagia was always observed; regurgitation, sialorrhea, and halitosis were frequent complaints, while weight loss, rumination, gurgling swallowing, odynophagia, and dry cough were only occasionally reported. Symptomatology lasted from 4 to 36 months (Me 16 months) in group A, and from 5 to 36 months (Me 12 months) in group B. ZD was complicated by hoarseness (1), inhalation (1), and ab ingestis pneumonia (2) in group A, and ab ingestis pneumonia (3: 2 episodes in 1 case) and inhalations (2) in group B. Comorbidities were found in all patients but two, mainly represented by vascular disorders and chronic obstructive pulmonary disease. Alzheimer’s disease, Parkinson’s disease, goiter, hepatitis C virus, myasthenia gravis, gastritis, mitral valve prolapse, and spondyloarthritis were also occasionally encountered. Symptoms referable to gastroesophageal reflux disease were found in 17/37 patients. Diverticulum size, radiographically calculated, ranged between 2.2 and 6 cm (Me 4 cm) in group A and between 2.5 and 6.6 cm (Me 4 cm) in group B. Intraoperative measurement of the emptied ZD was available for over 50 % of patients, and constantly showed values of about 50 % or less of the estimated radiological diameter. Patient data are summarized in Tables 1 and 2. Postoperative course No operative mortality or life-threatening complications were observed in either group.
The median follow-up duration was 37 months (range 12–113 months). No patients were lost during follow-up. One symptomatic recurrence was observed in group A. Four deaths for unrelated causes were observed in group A and one in group B. Gastromiro swallow studies were administered in all remaining patients (13 of group A, 19 of group B). Such control confirmed a 4 cm diverticular pouch relapse in the symptomatic patient of group A and demonstrated one small asymptomatic recurrence (10 and 12 mm in diameter) in each group. In addition to radiological findings, symptoms also recurred in one patient of group A, who complained of persistent dry cough and sialorrhea, occurring roughly 48 months after diverticulectomy, with no radiographic demonstration of relapse. The questionnaire indicated that the perceived preoperative clinical condition was practically the same in the two groups: in group A from 20 to 40 % (Me 30 %, mean 27.69 %) and in group B from 10 to 45 % (Me 30 %, mean 30.53 %). The assessed postoperative condition ranged from 20 to 100 % (Me 95 %, mean 87.69 %) in group A and from 90 to 100 % (Me 100 %, mean 98.16 %) in group B. Postoperative follow-up data are summarized in Tables 3 and 4. Statistical analysis Homogeneous comparative values for sex, age, diverticulum size, symptoms, and duration of symptoms were observed in the two groups. The statistical analyses identified two significant parameters (Table 5): 1.
Clinical control: the questionnaire revealed a slight but significant difference in favor of diverticulopexy regarding long-term postoperative condition (Me 100 %, range 90–100 % in diverticulopexy versus Me 95 %, range 20–100 % in diverticulectomy; p = 0.016, Mann–Whitney test).
123
123
67
61
77
66
62
79
69
49
48
75
66
57 69
90
65
62
61
M
M
M
M
M
F
M
F
M
F
F
M F
F
M
M
M
Dysphagia
Dysphagia, regurgitation
Dysphagia
Dysphagia, sialorrhea
Dysphagia, rumination Dysphagia
Dysphagia, regurgitation
Dysphagia, sialorrhea
Dysphagia, thoracic pain
Dysphagia
Dysphagia, dry cough
Dysphagia, regurgitation
Dysphagia, regurgitation
Dysphagia, regurgitation
Dysphagia, weight loss
Dysphagia, regurgitation
Dysphagia, regurgitation
Main symptoms
16
18
7
12
36 4
24
4
24
24
4
36
24
4
35
12
12
Duration of symptoms (months)
–
–
–
1 ab ingestis pneumonia
– –
1 ab ingestis pneumonia
Inhalation
–
Hoarseness
–
–
–
–
–
–
–
Complications
4
5
5
3
2.2 4
4
5
3.5
6
4
4
5
4.5
4
4
3
Diverticulum size (cm)
Gastritis
CAD
GERD
GERD, Parkinson’s disease
HCV Gastritis
HBP
GERD
GERD
–
GERD, Alzheimer’s disease
GERD
Spondyloarthritis
Gastritis
COPD, GERD
GERD
COPD
Comorbidities
COPD chronic obstructive pulmonary disease, GERD gastroesophageal reflux disease, HCV hepatitis C virus, CAD coronary artery disease, HBP high blood pressure
Age (years)
Sex
Table 1 Group A (diverticulectomy)
Esophagus
52
86
60
77
78
67 66
57
65
69
73
61
70
81
79
83
81
62
70
68
M
F
M
M
M
M M
M
M
M
M
M
M
M
M
F
M
M
M
M
Dysphagia
Dysphagia
Dysphagia
Dysphagia
Dysphagia, halitosis
Dysphagia, sialorrhea
Dysphagia, rumination
Dysphagia
Dysphagia, gurgles
Dysphagia, regurgitation
Dysphagia, sialorrhea
Dysphagia, rumination
Dysphagia, halitosis
Dysphagia, regurgitation Dysphagia, regurgitation
Dysphagia
Dysphagia, regurgitation
Dysphagia, regurgitation
Dysphagia, odynophagia
Dysphagia, thoracic pain
Main symptoms
18
24
18
24
12
24
12
9
12
12
5
12
36
12 18
6
5
12
6
8
Duration of symptoms (months)
–
–
–
–
–
–
–
–
–
Inhalation
–
–
–
Inhalation –
–
–
1 ab ingestis pneumonia
–
2 ab ingestis pneumonias
Complications
4
2.5
3
2.5
2.5
4
6.6
4
6
6
4
3
4.5
3.7 5
3
3.5
4
3
4
Diverticulum size (cm)
GERD, goiter
Mitral valve prolapse
–
GERD, CAD
GERD
GERD
Alzheimer’s disease
GERD
Myasthenia gravis
HBP
GERD
HBP
HP ? gastritis
COPD CAD
Parkinson’s disease
GERD
Goiter
GERD
GERD
Comorbidities
GERD gastroesophageal reflux disease, COPD chronic obstructive pulmonary disease, HP Helicobacter pylori. CAD coronary artery disease, HBP high blood pressure
Age (years)
Sex
Table 2 Group B (diverticulopexy)
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Esophagus Table 3 Group A follow-up records (diverticulectomy) Sex
Age (years)
Pre%
Post%
Table 5 Statistical comparison between the two groups
Complications
Relapse
Diverticulectomy
Diverticulopexy
p-Value
0.165
M
67
20
20
–
?
Age (years)
M
61
25
95
–
–
Me: 66.00
Me: 69.5
M
77
–
–
m: 66.06
m: 70.25
M
66
20
90
–
±
M
62
30
100
Microfistula
–
Me: 4.00
Me: 4.00
F
79
40
100
–
–
m: 4.129
m: 3.94
Diverticulum size (cm)
M
69
Transient VCP
–
F
49
30
95
–
–
Me: 30.00
Me: 30.00
M
48
25
100
–
–
m: 27.69
m: 30.52
F
75
20
90
–
–
F M
66 57
30 20
80 95
– –
? (Sym) –
F
69
Microfistula
–
F
90
–
–
M
65
40
90
–
–
M
62
30
85
Transient CBHs
–
M
61
30
100
–
–
VCP vocal cord paralysis, CBHs Claude Bernard–Horner syndrome, Sym recurrence only symptomatic with no evidence of disease. ± radiographic findings of relapse with no symptoms. Pre% preoperative condition, Post% postoperative condition (100 % completely asymptomatic, 0 % oral feeding impossible)
Preoperative quality of swallowing (questionnaire)
Sex
Age (years)
Pre% 20
M
52
F
86
M
60
25
M M
77 78
45 10
M
67
M
66
M
57
Post% 90
Complications
Relapse
–
±
–
–
100
–
–
100 100
– –
– –
40
95
–
–
25
100
–
–
35
90
–
–
M
65
30
100
–
–
M
69
30
95
–
–
M
73
30
100
–
–
M
61
25
100
–
–
M
70
25
95
–
–
M
81
30
100
–
–
M
79
30
100
–
–
F
83
40
100
–
–
M
81
40
100
–
–
M
62
30
100
–
–
M
70
30
100
–
–
M
68
40
100
–
–
± Radiographic findings of relapse with no symptoms, Pre% preoperative condition, Post% postoperative condition (100 % completely asymptomatic, 0 % oral feeding impossible)
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0.233
Postoperative quality of swallowing (questionnaire) Me: 95.00 m: 87.69
Me: 100.00 m: 98.157
0.016
1/20 (5.0 %)
0.343
0/20 (0 %)
0.036
Relapse 3/17 (17.6 %) Morbidity rate 4/17 (23.5 %)
Pre- and postoperative quality of swallowing: 100 % completely asymptomatic, 0 % oral feeding impossible. Morbidity rate: surgeryrelated complications Statistically significant values are indicated in bold Me median, m mean
2. Table 4 Group B follow-up records (diverticulopexy)
0.441
Morbidity rate: significant morbidity was recorded for diverticulectomy compared to diverticulopexy (p = 0.036, Fisher’s exact test).
Discussion The pathophysiology of the disease hypothesized by Zenker and Von Ziemssen in 1878 is still convincing [9]: ZD originates from repeated intraluminal pulsion against a site of weakness of the hypopharynx (Killian’s triangle) [10]. High pressure within the pharyngeal lumen is caused by an acquired incoordination between the propulsive contraction of the muscular wall of the pharynx and delayed, deficient or absent relaxation of the upper esophageal sphincter (UES) [11, 12]. The UES is mainly formed by the cricopharyngeal muscle and only secondarily by the inferior pharyngeal constrictor muscle. ZD can achieve considerable volume growth, especially when initial symptoms are ignored. Its enlargement and filling may result in anterior displacement of the esophageal axis with food stagnation and hampered emptying of the diverticular pouch [12, 13]; the marked anterior displacement of the esophageal axis is invariably linked to severe dysphagia (Fig. 2). Diagnosis is based on the patient’s medical history and physical examination, but is definitive when contrast swallow study results are indicative [12, 14]. When the
Esophagus
Fig. 2 Zenker’s diverticulum (a). Volumetric diverticular pouch enlargement and possible clinical implications (b, c)
patient complains of symptoms, the standard therapy is surgery, even in advanced elderly patients [15]. Cricopharyngeal myotomy eliminates the resistance that the UES offers to esophageal propulsion, eliminating the ensuing intraluminal pressure. There is no therapy for ZD without complete cricopharyngeal myotomy. For this reason the treatment of the diverticular pouch seems to be accessory, while cricopharyngeal myotomy is the therapeutic basis [5]. Myotomy causes UES relaxation, overcomes the pathologic incoordination, and restores normal intraluminal pressure. The length of the cricopharyngeal myotomy has also been focused on: it must include all the cricopharyngeal muscular fibers, along with a couple of centimeters of the proximal esophagus in order to be therapeutic and minimize the risk of recurrence [7]. Cicatricial processes after a short myotomy can result in relapse of symptoms. Lack or inadequacy of cricopharyngeal myotomy is the main pitfall of endoscopic procedures, as these techniques are blind [2]; in fact, small ZD represents a formal contraindication to transoral approach because the common wall is too short to accommodate the staple cartridge and to allow complete cricopharyngeal myotomy [5, 6]. Endoscopic treatment of diverticula larger than 2 cm proved to be safe and effective, although long-term results of large series are not available yet. Anyway, in our opinion, the surgical trauma of the transcervical approach is not so heavy to justify a blindly performed myotomy. Despite the progressive diffusion of endoscopic procedures in clinical practice, open approaches are still frequently chosen with various techniques, differing basically in the management of the diverticular pouch. Diverticulectomy and diverticulopexy are undoubtedly the most commonly used open techniques, but criteria for choice, comparative results, and pros and cons of the two procedures are undefined. The theoretical advantage of diverticulum suspension after myotomy is that the mucosa remains intact, without risks of fistulization and stenosis [16], while diverticulectomy could better restore the pharyngoesophageal anatomy by removing the redundant
mucosa. Both techniques are reproducible and effective, and ensure long-term palliation of symptoms [17]. Our study indicates that diverticulopexy as compared with diverticulectomy allowed for equivalent suppression of symptoms and slightly better long-term outcomes. Diverticulectomy entails the suture of a bare, not perfectly healthy mucosa, which is constantly affected by inflammatory changes and is not protected by any muscular layer. The risk of suture leakage is increased in case of incomplete myotomy (even if just a few fibers are left) because of the possible tension, due to the same intraluminal pulsion that is responsible for the pathophysiology of the disease. Our results concerning the timing of oral intake resumption and length of hospital stay were heavily influenced by the different physicians’ clinical attitudes; therefore these data were considered not homogeneous enough for statistical analysis. The optimal timing of solid oral refeeding after diverticulectomy is a matter of opinion: some authors advocated that stapled transcervical diverticulectomy may be followed by early oral refeeding [18], but it is not clear when a full solid diet can be administered safely. Anyway, regardless of the different clinical habits, the period of hospital stay and the time before resumption of a full solid diet are obviously shorter after diverticulopexy, because this method does not involve any esophageal suture. The longterm control with contrast swallow studies demonstrated that the pouch is virtually eliminated after both procedures, with a sort of restoration of the normal radiological anatomy; in fact, in our experience, a skilled radiologist was not able to distinguish the kind of procedure performed, on the basis of the findings of the contrast swallow test. So far, ZD size has been considered important for the technical choice: diverticulectomy has been usually favored for large diverticula, while diverticulopexy is preferred for smaller lesions [3, 19]. A cutoff point of 4 cm has been proposed as an indication for diverticulectomy [3]. We observed a significant mismatch between the calculated radiographic volume of the ZD and the intraoperative finding: in fact, the diameter of the emptied diverticulum was constantly much smaller than the radiographic measurement. This is a weak point in the concept that pouch management after cricopharyngeal myotomy should be tailored based on the preoperative contrast swallow test. The results of our study indicate that diverticulum suspension after cricopharyngeal myotomy is also suitable for large and aged lesions; a diverticular volume so large as to hamper its suspension is to be considered very rare and determinable only during surgery.
Conclusions The baseline of ZD therapy is cricopharyngeal myotomy. Diverticulectomy and diverticulopexy are called for in
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addition to myotomy in order to repair the lumen deformation; both provide good results and are dependable in the long term. Diverticulopexy could be preferred over diverticulectomy also for large ZD, because it achieves equivalent or even better results with lower operative risks.
7.
8. Ethical Statement This study was carried out in accordance with bioethic principles in medical research. The study is a retrospective analysis, and all patients were informed and joined the study on their own will. Conflict of interest There are no financial or other relations that could lead to a conflict of interest.
9.
10.
11. 12.
References 1. Smith SR, Genden EM, Urken ML. Endoscopic stapling technique for the treatment of Zenker diverticulum vs standard openneck technique: a direct comparison and charge analysis. Arch Otolaryngol Head Neck Surg. 2002;128:141–4. 2. Gutschow CA, Hamoir M, Rombaux P, Otte JB, Goncette L, Collard JM. Management of pharyngoesophageal (Zenker’s) diverticulum: which technique? Ann Thorac Surg. 2002;74: 1677–83. 3. Rizzetto C, Zaninotto G, Costantini M, Bottin R, Finotti E, Zanatta L. Zenker’s diverticula: feasibility of a tailored approach based on diverticulum size. J Gastrointest Surg. 2008;12: 2057–65. 4. Keck T, Rozsasi A, Grun PM. Surgical treatment of hypopharyngeal diverticulum (Zenker’s diverticulum). Eur Arch Otorhinolaryngol. 2010;267:587–92. 5. Lerut T, Van Raemdonck D, Guelinckx P, Dom R, Geboes K. Zenker’s diverticulum: is a myotomy of the cricopharyngeus useful? How long should it be? Hepatogastroenterology. 1992;39: 127–31. 6. Peracchia A, Bonavina L, Narne S, Segalin A, Antoniazzi L, Marotta G. Minimally invasive surgery for Zenker diverticulum.
123
13.
14. 15.
16.
17.
18.
19.
Analysis of results in 95 consecutive patients. Arch Surg. 1998;133:695–700. Brace M, Taylor SM, Trites JR, Bethune D, Attia E, Hart RD. Endoscopic stapling versus external transcervical approach for the treatment of Zenker diverticulum. J Otolaryngol Head Neck Surg. 2010;39:102–6. Lerut T, Coosemans W, Decaluwe´ H et al. Zenker’s diverticulum. MMCTS 2009 doi:10.1510/mmcts.2007.002881. Zenker FA, von Ziemssen HK. Krankheiten des Oesophagus. In: von Zeimssen HK, editor. Handbuch der Speciellen Pathologie und Therapie, 1st edn. Leipzig, D: Verlag von FCW Vogel; 1877. p. 1–87. Anagiotos A, Preuss SF, Koebke J. Morphometric and anthropometric analysis of Killian’s triangle. Laryngoscope. 2010;120: 1082–8. Belsey R. Functional disease of the esophagus. J Thorac Cardiovasc Surg. 1966;52:164–88. Van Overbeek JJ. Pathogenesis and methods of treatment of Zenker’s diverticulum. Ann Otol Rhinol Laryngol. 2003;112: 583–93. Cook IJ, Gabb M, Panagopulos V, Jamieson GG, Dodds WJ, Shearman DJ. Pharyngeal (Zenker’s) diverticulum in a disorder of upper esophageal sphincter opening. Am Gastroenterol Assoc. 1992;103:1229–35. Klockars T, Sihvo E, Makitie A. Familial Zenker’s diverticulum. Acta Otolaryngol. 2008;128:1034–6. Crescenzo DG, Trastek VF, Allen MS, Deschampes C, Pairolero PC. Zenker’s diverticulum in the elderly: is operation justified? Ann Thorac Surg. 1998;66:347–50. Laccourreye O, Me´nard M, Cauchois R, et al. Esophageal diverticulum: diverticulopexy versus diverticulectomy. Laryngoscope. 1994;104:889–92. Brigand C, Bajcz K, Elamrani H, Dan S, Rohr S, Meyer C. Traitment du diverticule de Zenker par diverticulopexie. J Chir. 2008;145:341–5. Busaba NY, Ishoo E, Kieff D. Open Zenker’s diverticulectomy using stapling techniques. Ann Otol Rhinol Laryngol. 2001;100: 498–501. Zaninotto G, Narne S, Costantini M, Molena D, Cutrone C, Portale G. Tailored approach to Zenker’s diverticula. Surg Endosc. 2003;17:129–33.