30: Resection of Esophageal Diverticula

Esophageal diverticula are unusual but interesting abnormalities that can develop in any part of the esophagus. The most common esophageal diverticulum occurs in the cervical region and is known as a Zenker diverticulum. An esophageal diverticulum may also occur in the midesophagus near the pulmonary hilum or as an epiphrenic diverticulum near the gastroesophageal junction. There are two categories of esophageal diverticula—pulsion and traction. Each has a distinct etiology. Pulsion diverticula are the most common type in the United States, and develop as a consequence of a motility abnormality in the esophagus distal to the site of the diverticulum.¹ They are false diverticula since they are not composed of the entire wall of the esophagus, but instead the mucosa herniates or protrudes through the muscle layers (Fig. 30-1).

The other type, traction diverticula, develop secondary to inflamed mediastinal lymph nodes, and represent a true diverticulum since all layers of the esophageal wall are involved. The prevalence of all types of diverticula increases with age.

Pulsion diverticula are the most common type of diverticula, and the most common pulsion diverticulum is a Zenker diverticulum. These develop in the cervical region secondary to repetitive pharyngeal pressure on boluses of food that are held up by a dysfunctional cricopharyngeus muscle.² Over time, this pressure causes a posterior herniation of the esophageal mucosa through Killian dehiscence, a weak point at the junction of the inferior constrictor and cricopharyngeus muscles. Epiphrenic diverticula are also pulsion diverticula. These develop secondary to a motility disorder in the distal esophagus, most commonly at the gastroesophageal junction and most commonly achalasia.³ Radiographically, pulsion diverticula typically have a wide neck, rounded contour, and retain contrast material on a barium swallow (Fig. 30-2). Symptoms associated with pulsion diverticula are often initially related to the underlying motility abnormality, but as the size of the diverticulum increases the symptoms may become more attributable to the pouch itself. Thus, while dysphagia is often the primary initial symptom, as the pouch enlarges, regurgitation may become more prominent. It is not unusual for these symptoms to lead to a misdiagnosis of gastroesophageal reflux disease before the diverticulum itself is identified (Fig. 30-3). However, careful questioning will usually elicit the key information that the regurgitated material tastes bland, not bitter, since the regurgitated food or fluid was trapped in the pouch and never made it to the stomach. Other symptoms attributable to a diverticulum are halitosis, cough, and aspiration of debris retained within the pouch. The larger and more proximal the pouch, the more troublesome these symptoms may be for patients.

Traction diverticula are caused by granulomatous inflammation of mediastinal lymph nodes, and occur most commonly in areas where tuberculosis or histoplasmosis is endemic. The inflamed nodes attach to the esophagus, and as the acute inflammation subsides, the nodes contract, pull on the esophagus, and create a conical outpouching. Traction diverticula are true diverticula, since the entire wall of the esophagus is involved. In contrast to pulsion diverticula, traction diverticula tend to have a pointed tip on radiographs and empty well on barium swallow (Fig. 30-4). Symptoms generally are less significant compared to patients with a pulsion diverticulum, and are related to the diverticulum or mediastinal inflammation since there is no underlying motility abnormality.

Surgery is the only effective therapy for esophageal diverticula. Dilation of the cricopharyngeus muscle has been attempted in patients with Zenker diverticulum with limited success. Even if the dilation is helpful, it only addresses the dysphagia component of the patient's symptoms. The surgical plan for patients with a pulsion diverticulum includes myotomy of the dysfunctional esophageal muscle adjacent and distal to the diverticulum and either excision or suspension of the diverticulum based on its size and location. Failure to divide the dysfunctional muscle leads to a high rate of recurrence and increases the risk of a leak from the suture or staple line if the diverticulum has been excised.⁴ For patients with a symptomatic traction diverticulum, only excision of the diverticulum is necessary, but the fibrotic nodes that caused the diverticulum can make the dissection tedious. Approaches to both pulsion and traction diverticula include the traditional open techniques and more recent transoral, laparoscopic, and thoracoscopic minimally invasive options. Given the absence of effective nonsurgical therapy and the relative safety of most of these procedures, symptomatic patients with an esophageal diverticulum should be considered for surgical therapy regardless of age.

The physical examination of patients with an esophageal diverticulum generally is unrevealing, even when a large Zenker diverticulum. However, if a transoral approach for correction of a Zenker diverticulum is being considered, it is important to assess the ability of the patient to adequately open the mouth and extend the neck.⁵

The best way to visualize an esophageal diverticulum is with a barium swallow.⁴ Our preference is a video swallow esophagogram, since in addition to showing the size and location of the diverticulum, it provides information about the efficacy of bolus transport by the esophageal body and the presence of a hiatal hernia or other abnormalities. Upper endoscopy is useful both to measure the size and location of the diverticulum, and to evaluate the esophageal mucosa for any abnormalities, particularly in elderly patients where it is essential to rule out malignancy.

Esophageal manometry is important to evaluate the underlying motility abnormality. It is usually necessary to pass the motility catheter using endoscopic guidance, as the catheter may otherwise coil in the diverticulum. Motility studies in patients with a Zenker diverticulum are often normal and are not necessary. The upper esophageal sphincter is composed of skeletal muscle, in contrast to the smooth muscle of the lower esophageal sphincter, and standard motility techniques lack sufficient sensitivity to reliably detect the underlying abnormality. Motility findings that might be present in a patient with a Zenker diverticulum include an increased bolus pressure in the pharyngeal contraction wave (evidence of outflow obstruction distally) and mistimed or incomplete relaxation of the cricopharyngeus with a swallow.² Most patients with a Zenker diverticulum are elderly, and the cause of the cricopharyngeal dysfunction is usually related to prior neck injury, radiation, or neurologic abnormalities such as a stroke. Young patients (<50 years old) with a Zenker diverticulum often have no predisposing factors, but frequently have symptoms of gastroesophageal reflux disease. This raises the possibility that proximal reflux can induce dysfunction of the cricopharyngeus muscle and lead to the development of a Zenker diverticulum. Certainly, reflux should be considered and further evaluated if present in an otherwise healthy patient under age 50 who presents with a Zenker diverticulum.

Transcervical Cricopharyngeal Myotomy and Diverticulectomy or Suspension

The traditional approach for repair of a Zenker diverticulum is transcervical, with the patient positioned supine and the neck extended. An incision is made in the left neck along the anterior border of the sternocleidomastoid muscle. The sternocleidomastoid muscle and carotid sheath are retracted laterally. The omohyoid, sternothyroid, and sternohyoid muscles are divided to facilitate exposure of the cervical esophagus. The Zenker diverticulum will be located posterior to the cricoid cartilage. The diverticulum is sheathed in multiple layers of fibrous tissue that must be teased apart to permit exposure of the base of the diverticulum (Fig. 30-5).

Once exposed, a longitudinal myotomy on the posterolateral aspect of the cervical esophagus is started just inferior to the base of the diverticulum. It should extend inferiorly to the thoracic inlet, and then it is carried superiorly through the muscular ring of the cricopharyngeus at the base of the diverticulum. Typically, the muscle in the area of the base of the diverticulum is quite thick and fibrotic. Once released, the diverticulum should be clearly visualized. To ensure that all the dysfunctional fibers are divided, we also incise the lower fibers of the inferior pharyngeal constrictor superiorly from the base of the diverticulum for 1 to 2 cm. In addition, the edges of the divided muscle should be bluntly dissected to widely splay open the mucosa and permit identification and division of any residual circular muscle fibers.

Next, the diverticulum is either suspended or excised. Diverticula 2 cm or less in size are easily suspended by tacking the tip of the diverticulum with 3-0 Prolene to the precervical fascia as high up in the neck as necessary to fully upend the pouch. Larger pouches are difficult to fully upend and are best excised using a TA stapler with a 52F bougie in the esophagus to prevent narrowing of the esophageal lumen. The staple line and/or myotomy can be checked for leaks by passing a nasogastric tube into the area and insufflating air to distend the mucosa while the neck incision is filled with saline. This also provides an opportunity to ensure the mucosa distends fully with no residual bands in the area of the myotomy. Before neck closure, it is critical to ensure perfect hemostasis, because a hematoma requiring reexploration can develop from even small vessels secondary to coughing or straining as the patient awakens from anesthesia. We leave a small closed suction drain in place and approximate the platysma and skin to complete the operation.

Transoral Endoscopic-Stapled Diverticulotomy

A transoral endoscopic approach is another option for treating a Zenker diverticulum. This approach is attractive largely because it eliminates the neck incision, but limited because the pouch must be at least 3 cm in length and the patient must be able to extend the neck and open the mouth widely. Inability to extend the neck and open the mouth makes placement of the Storz rigid diverticuloscope difficult or impossible. If the diverticulum is less than 3 cm in length, it may not be possible to completely divide the dysfunctional cricopharyngeus muscle, leading to persistent or recurrent symptoms. Patients with evidence of malignancy inside the pouch are also not candidates for transoral stapling technique and instead require excision of the pouch.⁶ Although the procedure is quick and well tolerated, and in suitable patients produces excellent relief of dysphagia and regurgitation symptoms, patients must be warned of the possibility of chipped teeth secondary to the rigid scope insertion. In addition, most patients have considerable tongue swelling for a day or two after the procedure.

Before the procedure commences, a 30-mm GIA laparoscopic stapler is modified by cutting off the tip of the stapler with an orthopedic circular saw such that the knife blade and the staple line reach the end of the modified tip. The tip should be smoothed with a rasp or file. The patient is placed under general anesthesia and positioned supine with the neck extended, and the Storz diverticuloscope is inserted under direct visualization and advanced into the esophagus. It is helpful to have a pediatric flexible esophagoscope to facilitate placement of the rigid scope. The goal is to advance the longer anterior blade into the true lumen of the esophagus whereas the shorter posterior blade is advanced into the diverticulum. Once positioned, the blades of the scope are separated to permit clear visualization of the cricopharyngeus muscle band (Fig. 30-6). Using a laparoscopic needle holder, 3-0 Prolene traction sutures are placed on each side of the cricopharyngeus muscle (Fig. 30-7). With gentle traction on these stitches, the bar is held in position as the modified GIA stapler is inserted and fired (Fig. 30-8). Several applications of the stapler are typically necessary to divide the muscle bridge all the way to the tip of the diverticulum (Fig. 30-9). In this fashion, the cricopharyngeus muscle is divided, and the pouch is incorporated into the esophagus to create a single common cavity. If the diverticulum is less than 3 cm in length, the cricopharyngeus muscle will not be adequately divided, leading to a high rate of symptomatic failure and a significant risk for the development of a recurrent diverticulum. It is important to modify the stapler to minimize the amount of residual pouch with the transoral approach, since even a 1-cm remnant can lead to persistent symptoms. Although it is nearly impossible to completely eliminate the pouch, in our experience, patients with less than 4 to 5 mm of residual pouch remain asymptomatic.

Laparoscopic, Transabdominal, or Transthoracic Esophageal Myotomy; Diverticulectomy; and Partial Fundoplication (Triple Treat)

The objectives of the procedure for an epiphrenic diverticulum are identical regardless of the approach, and include division of the dysfunctional esophageal muscle distal and adjacent to the diverticulum, excision of the diverticulum, and partial fundoplication to protect the esophagus from gastroesophageal reflux.^1,7 A myotomy that ends at the gastroesophageal junction is associated with a higher incidence of persistent or recurrent dysphagia compared to a myotomy that extends 2 to 3 cm onto the gastric side of the junction.^1,7,8 In our opinion the best location for the myotomy is along the left lateral aspect of the esophagus with continuation down across the angle of His on the greater curvature side of the stomach. Further, it is clear that the addition of a partial fundoplication reduces esophageal acid exposure after myotomy,⁹ and therefore a partial fundoplication is added to the myotomy in all patients.

Epiphrenic diverticula can be treated via a transabdominal or transthoracic approach, and as an open or minimally invasive procedure depending on the size and location of the diverticulum. If the diverticulum is located near the hiatus, a laparoscopic diverticulectomy with esophageal myotomy and partial fundoplication is readily accomplished, but it is important to recognize that many diverticula are more proximal than they appear radiographically, and only those very close to the gastroesophageal junction are amenable to a transabdominal or laparoscopic approach (Fig. 30-10). Some epiphrenic diverticula are located 5 to 10 cm proximal to the gastroesophageal junction, and for these patients, a transthoracic approach is optimal. The approach is via left thoracotomy in the eighth intercostal space. After incision of the mediastinal pleura and identification of the esophagus, the diverticulum can be dissected. Once the diverticulum is dissected it can be excised using a TA stapler with a 52F or larger bougie in the esophagus to avoid narrowing the lumen. Subsequently, the muscle is reapproximated over the staple line with interrupted 3-0 silk sutures (Fig. 30-11), and a myotomy is performed on the opposite side of the esophagus and carried down for several centimeters on the greater curvature side of the stomach (Fig. 30-12). Typically, a Dor partial fundoplication is performed (Fig. 30-13), but if there is a hiatal hernia, then crural closure with a Belsey partial fundoplication is preferred. Diverticula underneath the aortic arch are difficult to excise from the left chest and are better visualized from the right. In this setting, a two-stage approach offers some advantages. The first stage is a laparoscopic myotomy and partial fundoplication, and then 6 weeks later the patient can be brought back for a thoracoscopic diverticulectomy and long esophageal myotomy through the right chest.

Traction diverticula occur secondary to mediastinal adenopathy, and a myotomy is unnecessary. Treatment entails separating the esophagus from the culprit nodes (often difficult secondary to intense inflammation, fibrosis, and/or calcification) and excising the diverticulum. This is best accomplished in most patients via the right chest either as an open or thoracoscopic procedure. It is recommended that pleura or intercostal muscle is placed between the esophageal repair and any residual mediastinal nodes to prevent leakage or recurrence.

Patients are kept NPO after the procedure until the following day, or 24 to 48 hours longer when the diverticulum has been excised. We typically obtain a Gastrografin esophagogram before starting oral feeds, both to document the integrity of the myotomy ± diverticulectomy staple line and to verify that the patient is able to swallow without aspiration, particularly in a patient who has undergone surgery for a Zenker diverticulum.

Major morbidity is uncommon, but potential complications include a leak from the myotomy or suture line if the diverticulum was excised, mediastinitis, fistula formation, hoarseness from vocal cord paralysis, incomplete myotomy, luminal stenosis, and wound infection. Long-term complications include recurrence of the diverticulum, particularly if no or an inadequate myotomy is done in patients with a pulsion-type diverticulum, and development of gastroesophageal reflux when the myotomy is carried across the gastroesophageal junction. Most procedures are well tolerated, have minimal morbidity, and provide excellent symptomatic relief for patients.

Esophageal diverticula are uncommon but interesting esophageal abnormalities. The pulsion-type diverticulum develops as a consequence of an underlying esophageal motility disorder, and occurs most commonly in the cervical region as a Zenker diverticulum. These are false diverticula, and treatment entails a myotomy through the dysfunctional muscle distal to the diverticulum with suspension or resection of the diverticulum. For epiphrenic diverticula a partial fundoplication is added to complete the so-called “triple treat.” The other type of diverticulum is called a traction diverticulum. These develop secondary to inflamed mediastinal lymph nodes and are true diverticula that involve the entire esophageal wall. Treatment for symptomatic patients entails excision of the diverticulum.

Surgical therapy should be considered in all symptomatic patients since there is no effective medical therapy for the regurgitation and aspiration problems associated with a diverticulum. In addition to the traditional open approaches, new minimally invasive or transoral approaches are applicable in some patients and may reduce procedure-related morbidity and hasten recovery. Careful patient evaluation and technical precision during the procedure will ensure excellent results.

An 85-year-old woman was referred with a 5-year history of dysphagia, primarily for solid food and pills, but occasionally for liquids if she drank too quickly. She also noticed a frequent gurgling sensation in the neck and experienced regurgitation of undigested food particles, particularly at night when lying down. She endured severe heartburn symptoms for 20 years that she self-treated with over-the-counter medications, but recently was placed on Prilosec with excellent relief.

On physical examination, her neck was supple with good extension, and she was able to open her mouth widely. She had a barium swallow study that revealed a several-centimeter Zenker diverticulum and a sliding hiatal hernia. She underwent an upper endoscopy, which demonstrated an approximately 3-cm Zenker pouch, a sliding hiatal hernia, and a columnar-lined distal esophagus with intestinal metaplasia on biopsy. She was offered surgical therapy for her Zenker diverticulum. The option of open versus transoral endoscopic approach was discussed, and it was thought that she would be a good candidate for the transoral technique.

Under general anesthesia, she was positioned with the neck extended. A Storz diverticuloscope was introduced transorally and advanced into the esophagus. The pouch was exposed but was determined to be of insufficient size to permit complete division of the cricopharyngeus muscle. Therefore, the diverticuloscope was withdrawn, and the patient had an open cricopharyngeal myotomy with suspension of the diverticulum. She had an uncomplicated postoperative hospital course and reported significant improvement in her swallowing. A barium swallow study showed a widely patent cricopharyngeal region with no filling of the suspended Zenker pouch.

When suspending a Zenker diverticulum, one must be cautious not to directly suture it to the prevertebral fascia, as this can result in osteomyelitis. A better place to suture is the cricopharyngeal muscle proximally. Furthermore, many patients presenting with symptoms consistent with Zenker diverticulum are elderly and frail and must be carefully monitored postoperatively. One must also exclude from surgery those who have neurologic etiology for their esophageal dysfunction.

Occasionally, a relatively small epiphrenic diverticulum can be treated by laparoscopic Heller myotomy and Dor fundoplication without diverticulectomy, particularly when the symptoms are mostly obstructive. Finally, there are those patients with severe long-standing reflux who develop strictures that result in small diverticulum. These patients require careful preoperative assessment to identify and will likely require a full wrap to effectively treat their reflux.