Simulated Zenker's endoscopic staple-assisted esophagodiverticulostomy (ESED) surgery

A systematic review of low-cost simulators in ENT surgery

BACKGROUND

Simulation training has become a key part of the surgical curriculum over recent years. Current trainees face significantly reduced operating time as a result of the coronavirus disease 2019 pandemic, alongside increased costs to surgical training, thus creating a need for low-cost simulation models.

METHODS

A systematic review of the literature was performed using multiple databases. Each model included was assessed for the ease and expense of its construction, as well as its validity and educational value.

RESULTS

A total of 18 low-cost simulation models were identified, relating to otology, head and neck surgery, laryngeal surgery, rhinology, and tonsil surgery. In only four of these models (22.2 per cent) was an attempt made to demonstrate the educational impact of the model. Validation was rarely formally assessed.

CONCLUSION

More efforts are required to standardise validation methods and demonstrate the educational value of the available low-cost simulation models in otorhinolaryngology.

Simulation of KTP Laser-Based Zenker Diverticulotomy with a Porcine Model and Laryngeal Dissection Station

Zenker’s diverticulum is a rare cause of progressive dysphagia that is treated surgically. Potassium titanyl phosphate (KTP) laser–based diverticulotomy is one effective treatment. Developing a simulation model is helpful for rare conditions. Pigs have a natural hypopharyngeal pouch similar to a diverticulum. We present a model for performing rigid endoscopic KTP laser diverticulotomy in a porcine model with a laryngeal dissection station. Eleven pigs were examined to confirm presence of the hypopharyngeal pouch. A specimen was mounted on the modified laryngeal dissection station, and a KTP laser–based diverticulotomy was performed. Novel aspects include use of the laryngeal dissection station and application of the model for simulating rigid endoscopic KTP laser diverticulotomy. This model allows trainees to practice equipment setup, positioning of the laryngoscope to isolate the cricopharyngeal bar, tissue handling, laser safety techniques, and use of the KTP laser through the laryngoscope under microscopic visualization.

Endoscopic management of Zenker's diverticulum: factors predictive of success or failure

OBJECTIVES

We review our experience with endoscopic management of Zenker's diverticulum. We sought to analyze and determine risk factors for success or failure of endoscopic diverticulum treatment.

METHODS

We performed a retrospective review of 72 consecutive patients who underwent attempted endoscopic management of a Zenker's diverticulum between January 2000 and April 2006. The procedures were performed by either of 2 otolaryngologists. There were 50 men and 22 women ranging in age from 44 to 93 years. A total of 85 procedures were performed. The medical records were reviewed for preoperative diverticulum size (small, 1 to 2 cm; moderate, 2.1 to 3.0 cm; and large, more than 3.0 cm), intraoperative diverticulum characteristics, patient anatomic limitations that prevented adequate endoscopic visualization, surgical complications, and management of recurrences.

RESULTS

Of our 72 patients, 61 (85%) were able to undergo endoscopic cricopharyngeal myotomy with diverticulum elimination. Of the 61 endoscopic procedures, 47 (77%) resulted in complete symptom resolution. The most common risk factors for recurrence were diverticulum size (more than 3 cm) and amount of redundant mucosa. Of the 14 patients with a recurrence, 10 (71%) underwent a repeat procedure. Six of the 14 (43%) had a successful excision via a cervical approach, and 4 of the 14 (29%) underwent a repeat endoscopic myotomy. There was 1 major complication (esophageal tear), and there were 3 minor complications (mucosal abrasions).

CONCLUSIONS

Most patients with a Zenker's diverticulum are good candidates for endoscopic management. In our series, 84% of those who underwent endoscopic treatment ultimately achieved relief of symptoms. The patient morbidity is minimal. A large diverticulum with redundant mucosa is a risk factor for recurrence after endoscopic treatment.

An animal training model for endoscopic treatment of Zenker's diverticulum

BACKGROUND

Zenker's diverticulum (ZD) is an uncommon disease, which is typically treated surgically. The alternative to surgery is a diverticulotomy, performed endoscopically. Given the rarity of this condition, it is not possible to obtain training. There has been no animal model identified that resembles the disease in human beings.

OBJECTIVE

To present an animal model of ZD that resembles the disease in human beings.

DESIGN

We prospectively characterized the endoscopy, the radiography, and the histologic anatomy of the pharyngeal diverticulum in the pig.

SETTINGS

Domestic pigs scheduled for euthanasia underwent radiography and endoscopy and, after euthanasia, neck dissection of the pharyngeal diverticulum.

INTERVENTIONS AND METHODS

Thirteen consecutive animals were studied. Pictures were taken for the endoscopic view, as well as radiographies during barium swallow in 1 pig. The neck region was dissected, and the pharynx and the upper esophagus were extracted. The size of the diverticulum was measured, and the block was fixed in formalin. Fixed specimens were cut in the transverse and coronal axis, and pictures were taken. The septum between the diverticulum and the esophagus was reviewed microscopically.

RESULTS

The pharyngeal diverticulum measured an average of 2.7 cm (1.3-5 cm), depending on the size of the pig. From an endoscopic and radiologic perspective, the pig pharyngeal diverticulum is identical to a ZD. The septum contains muscle as well as fibrous tissue and fat. These anatomical characteristics closely resemble the anatomy in human beings.

CONCLUSIONS

We believe that we established an animal training model for the endoscopic treatment of ZD.

Myotomy length determinants in endoscopic staple-assisted esophagodiverticulostomy for small Zenker's diverticula

A small Zenker's pouch is a major challenge for endoscopic staple-assisted esophagodiverticulostomy (ESED). This study tested the stapler dimensions so as to identify limitations they impose on ESED. Combining ESED with additional endoscopic suturing could extend the incision and consequently the myotomy. Zenker's diverticulum residual pouch measurements were performed with a previously reported latex glove model and in patients undergoing surgery. Two stapler designs were compared by measuring the residual pouch length for both the stock and modified staplers. One other stapler model cannot be modified without damaging the mechanism. The Endostitch was used to place an additional suture at the apex of the staple line, allowing cutting between the staples while leaving a closed distal incision. All three staplers suitable for ESED leave a residual pouch of 1.5 cm when unmodified. The modified anvil staplers gave a smaller residual pouch by 4 to 5 mm. An additional septal reduction can be accomplished by suturing the area distal to the staple line and incising the party wall beyond the stapler cut. The absolute amount of residual pouch with an additional myotomy is 3 mm. The combined staple-suture technique has proven relatively safe thus far. To provide a maximally efficient myotomy in a patient with a short pouch, the surgeon needs to be aware of the stapler differences. Modifications of the staplers may decrease the depth of the residual pouch, but may carry an added liability. A minimum residual pouch can be achieved with a combination of stapler and suture techniques, but is more technically demanding than the original ESED description.

Endoscopic management of Zenker diverticulum: the staple-assisted approach

Hypopharyngeal (Zenker) diverticulum is a physiologic obstruction of the esophageal entroitus due, at least in part, to reflux irritation. Endoscopic techniques have largely replaced the traditional treatment, comprising external excision and myotomy. In this article, the classic Dohlman technique is compared with the newer endoscopic staple-assisted esophagodiverticulostomy, which provides an endoscopic approach to Zenker diverticulum-associated dysphasia. This technique can be practiced with a simulator, requires little experience, has a good safety record, and has acceptable results.

Carbon dioxide laser diverticulostomy: a new treatment for Zenker diverticulum

In the United States, the traditional treatment for hypopharyngeal (Zenker) diverticulum has been single-stage transcutaneous diverticulectomy. Complications following this procedure include mediastinitis, vocal cord paralysis, esophageal stenosis, fistula, and recurrent or persistent diverticula. The development of endoscopic equipment has led to a new era of surgery for this condition. Magnification of anatomic landmarks allows for better precision during surgery and reduces both surgical procedure time and postoperative complications. Additional techniques, such as diathermy, bipolar coagulation, stapler, and laser surgery, all of which decrease intraoperative bleeding, lend further support to the procedure. In several randomized controlled clinical trials, endoscopic laser treatment of diverticulum has demonstrated the best results in terms of decreased morbidity and fewer complications. Thus, laser approaches for treating Zenker diverticulum deserve consideration.