Endoscopic treatment of Zenker's diverticulum in the esophagus

Posted by Doctor Mai Vien Phuong - Department of Medical Examination & Internal Medicine - Vinmec Central Park International General Hospital.

Zenker's diverticulum is a diverticulum in the esophagus that occurs in the elderly and contributes to morbidity from dysphagia and aspiration pneumonia. Open surgery and rigid bronchoscopy were formerly the mainstays of treatment, however, with favorable safety characteristics and similar success rates, flexible bronchoscopy has become a new modality in the treatment of patients. Treatment of Zenker's diverticulum. This review aims to highlight laparoscopic techniques and tools in the management of Zenker diverticulum.

Zenker's diverticulum, first reported by Ludlow in 1769, is an esophageal pouch characterized by herniation posteriorly through the Killian triangle or Killian dehiscence, anatomically located higher than the pharyngeal muscle and inferior to the pharyngeal muscle. lower pharyngeal constriction. After a series of detailed cases of Zenker's diverticulum were published in 1867 by Friedrich Zenker, the entity was given its own name. An uncommon entity with a reported prevalence of 0.01%-0.11%, Zenker's diverticulum typically presents in the seventh to eighth decade, with a male predominance.

Although the mechanism of development is not entirely clear, decreased opening of the upper esophageal sphincter (UES) leads to increased intraluminal pressure and subsequent tissue migration through a defect. anatomic defect has been suggested; Structural abnormalities of the cricopharyngeal muscle are thought to explain the decreased relaxation of the upper esophageal sphincter and increased intraluminal pressure. Reported to be associated with GERD, also with an unclear mechanism, acid-induced muscle shortening has been proposed as a unified hypothesis linking the two conditions.
This diverticular condition, causes symptoms such as: dysphagia, postprandial vomiting, regurgitation of food, retained food and other substances in the pouch cavity, halitosis, cough, weight loss, malnutrition nutrition and aspiration pneumonia. Dysphagia in patients with Zenker's diverticulum that can manifest as malnutrition has been reported in 54% of patients across a range of illnesses. Zenker's diverticulum is associated with an endoscopic capsule that becomes trapped at full and is subsequently retrieved endoscopically. There are also case reports of Zenker's diverticulum complicated by the presence of intravesical carcinoma, however this is extremely rare.
The most common modality for diagnosis is contrast-enhanced esophagography (eg, barium esophagography / barium swallow, flexible bronchoscopy, CT thoracic scan. There are limited reports of features. of Zenker's diverticulum on ultrasound, however this played no role in the initial diagnosis.Verified scoring tools for the assessment of dysphagia (SWAL-QOL, Dakkak-Bennet) reported and used to assess status before and after intervention.

Previously the mainstay of treatment was open surgical correction and endoscopic management with rigid endoscopes, but advances in soft endoscopic tools and techniques have brought flexible endoscopic management to the fore. past two decades. This review aims to highlight laparoscopic techniques and tools in the management of Zenker diverticulum.

Although there are no specific guidelines for treatment, intervention should be reserved for symptomatic patients only. Current treatment modalities are open surgery (including diverticulectomy, diverticulectomy, diverticulectomy, diverticulectomy), rigid endoscopic (electrocautery, CO2 laser, stapler, Harmonic scalpel) ) and flexible endoscopy. As previously reported, the successful management of Zenker's diverticulum was comparable among the three established modalities, however adverse events including mortality were significantly lower in the flexible laparoscopic approach. Rigid and soft endoscopy share similar outcome profiles, but soft endoscopy by some authors does not require general anesthesia.

The first flexible endoscopic therapy for Zenker's diverticulum was reported in 1995. The main treatment focused on division of the pharynx muscle through laparoscopic myotomy that resulted in the obliteration of the diverticulum space. and improve dysphagia; with a variety of accessories (APC, bipolar forceps, specialized cutters, transparent endoscope caps (CAPs), hook knives, needle knives) and new techniques (Z-POEM) for the endoscopist handling, flexible and effective laparoscopic methods for the treatment of Zenker's diverticulum.

The flexible endoscopic diverticulectomy (FESD) technique is an incision of the mucosa and muscle, partially or completely, of the pharyngeal muscle leading to the division of the septum. In a recent meta-analysis, flexible laparoscopic diverticulectomy reported an overall good outcome with a pooled success rate of 91%, an overall adverse event rate of 11.3%, and an overall adverse event rate of 11.3%. The overall recurrence rate was 11%. Because there is no standardized technique for laparoscopic diverticulectomy, there is wide heterogeneity between studies and multiple approaches to septal division. Most laparoscopic approaches to flexible laparoscopic diverticulectomy are multimodal with a combination of accessories or techniques used. The thin nature of the diverticulum increases the risk of perforation, as it can be confused with the lumen of the esophagus.
The advent of transparent flaps (CAP) and diverticuloscopes (Cook Medical, Winston-Salem, NC) have improved endoscopic visibility and outcomes. The diverticuloscope and cap device allow for improved imaging through septal exposure and immobilization, and aid in fiber separation by gently spreading pressure. When using diverticuloscope, the procedure time is greatly reduced.

Widely reported, the use of Savary leads with nasogastric (NG) catheterization to delineate the esophagus from the foramen of Zenker's diverticulum and protect the anterior wall of the septum during myomectomy . There are also differences in the literature regarding the use of closing forceps at the end of the procedure and the antibiotics given before and after endoscopic therapy.
Post-interventional care lacks a standardized approach that mainly consists of hospital follow-up, a soft diet, and a contrast-barrier comparison study to assess perforation. The incidence of complications (cervical perforation/emphysema, hemorrhage) varies with flexible laparoscopic diverticulectomy, but is generally still relatively low, and is primarily treated with a laparoscopic approach. careful. Symptomatic recurrence rates vary, most of which are acceptable repeat laparoscopic diverticulectomy with reasonable results.

Needle knife
Ishioka et al. reported the first flexible laparoscopic diverticulectomy technique in 1995; Intervention was performed with Needle-Knife (NK) and improved in all patients in the series (N=23). Further studies detailed efficacy in laparoscopic treatment of Zenker's diverticulum. Costamagna et al evaluated the prognostic variables for the success of flexible laparoscopic diverticulectomy and reported short- and long-term success (6 and 48 months, respectively). Correlation with length and septal size of Zenker's diverticulum. Criticism of the needle knife's approach is concern about the risk of perforation. Hesitancy to lengthen the septum due to lack of direct visualization may contribute to the recurrence rate.
Hook Knife (Olympus Corporation, Center Valley, PA, USA) was first reported by Recipe to show clinical efficacy in septal resection; This finding has been reproduced in subsequent studies and clinical trends seem to favor the Hook Knife as the preferred laparoscopic tool for flexible laparoscopic diverticulectomy. The inherent advantage of the Hook Knife is that it pulls the muscle fibers upward prior to excision minimizing the risk of perforation at the time of intervention.

Heat therapy
Mulder et al. first reported on an experimental study in which Argon Plasma Coagulation (APC) was used to perform flexible laparoscopic diverticulectomy with improved symptomatic and without AE; Similar results have been reported with different reports of perforation as a modality concern.

Submucosal endoscopic diverticulectomy (STESD/Z-POEM) is a novel laparoscopic technique for the management of Zenker's diverticulum that was first reported by Li et al. Z-POEM was created using techniques ranging from the POEM to reduce the risk of perforation seen with flexible endoscopic diverticulectomy, reported 6.5 % patient. The Z-POEM approach consists of the following four steps: mucosal incision (consisting of 3cm submucosal injection near the septum and 1-2 cm longitudinal mucosal incision to create access to the tunnel), submucosal tunneling (to the end of the pouch or 1–2cm distal), resection of the diverticulum and closure of the mucosa (via endoclips.Reports from a small case series have shown that Z-POEM shows good success with return to normal anatomy, without perforation, and resolve symptoms at follow-up Limited data and expert knowledge are needed to perform limited POEM Z-POEM as a common treatment modality
.

Flexible laparoscopic diverticulectomy with Clutch Cutter (Fujifilm, Tokyo, Japan) has shown promise when used with or without a clear flap; To the authors' knowledge, there are only two case reports, both of which reported success. This device, originally designed for endoscopic submucosal dissection (ESD), is not FDA approved.
Beetle Stag Knife (SB-Knife; Sumitomo Bakelite, Tokyo, Japan) was first reported in the use of diverticulectomy in 2013. Originally designed for dissection technique submucosal ESD, SB-Knife has shown good results in a series of case reports and small series. With the simultaneous use of an overtube, the septal opening of the diverticulum was performed in a midline fashion, which is a novel approach by creating two lateral dissections. Although success has now been reported, further prospective trials are needed to determine long-term efficacy and recurrence rates.

Advances in endoscopic tools, with similar efficacy and reduced risk of complications compared with previously accepted surgical and rigid endoscopic modalities, are increasingly making endoscopic therapy became the “first-line” approach in the management of Zenker diverticulum. The introduction of diverticuloscope has allowed for better results in the European case series, due to a more stable endoscopic field and improved imaging during septal division. In the United States, a transparent lid also serves a similar purpose. Emerging tools such as the SB-Knife and Clutch Cutter are likely to deliver improved results because they allow for grip and heat therapy, limiting the risk of perforation. New endoscopic methods such as Z-POEM appear promising but are limited by the required endoscopic skills and lack of data.

References
Ludlow, A., A case of obstructed deglutition from a preternatural dilatation of and bag formed in the pharynx. Med Observ Inq, 1769. 3: p. 85-101. Haubrich, W.S., von Zenker of Zenker's diverticulum. Gastroenterology, 2004. 126(5): p. 1269. Law, R., D.A. Katzka, and T.H. Baron, Zenker's Diverticulum. Clin Gastroenterol Hepatol, 2014. 12(11): p. 1773-82; quiz e111-2. Watemberg, S., O. Landau, and R. Avrahami, Zenker's diverticulum: reappraisal. Am J Gastroenterol, 1996. 91(8): p. 1494-8