Postoperative Esophagus





General Principles


Radiologic evaluation of the postoperative esophagus requires an understanding of the operative procedures and of the normal postoperative radiologic appearances. The purpose of the radiologic examination is to do the following: (1) define the postoperative anatomy and establish a baseline; (2) assess the efficacy of the procedure; and (3) detect complications during the early (<4 weeks after surgery) or late (>4 weeks after surgery) postoperative periods. During the early postoperative period, the most common complications include stasis resulting from adynamic ileus or vagotomy, obstruction resulting from anastomotic edema, and perforation resulting from anastomotic breakdown ( Box 27-1 ). During the late postoperative period, the most common complications include aspiration, gastroesophageal reflux, anastomotic strictures, and recurrent tumor (see Box 27-1 ).



Box 27–1

Complications of Esophageal Surgery


Early Complications


Common Complications





  • Anastomotic or staple line leak



  • Anastomotic narrowing



  • Gastric or duodenal atony



  • Aspiration



  • Gastroesophageal reflux



  • Delayed bypass emptying




    • Anastomotic edema



    • Anastomotic narrowing



    • Gastric or duodenal atony



    • Obstruction at diaphragm—pyloric channel obstruction or spasm




Uncommon Complications





  • Pneumothorax



  • Pneumomediastinum



  • Mediastinal hematoma



  • Empyema



  • Vocal cord paresis



  • Chylothorax



  • Ischemia of colonic or jejunal bypass



  • Splenic injury



  • Pancreatitis



Late Complications


Common Complications





  • Anastomotic stricture



  • Aspiration



  • Recurrent carcinoma



  • Gastroesophageal reflux and its sequelae



Uncommon Complications





  • Delayed conduit emptying



  • Tracheoesophageal fistula



  • Anastomotic or staple line leak




An anastomotic or staple line leak is the most common serious complication of esophageal surgery ( Fig. 27-1 ). Sutures and staples hold less well in the esophagus than elsewhere in the gastrointestinal tract because the esophagus lacks a serosa, esophageal muscle is stringy and soft, and mucosa retracts from the cut esophageal margin because of mobility between the squamous mucosa, fatty submucosa, and muscularis propria. Leaks also occur at staple lines because of focal ischemia caused by the crush effect of the staple line on viable tissue. A delay in the diagnosis of postoperative perforation leads to increased morbidity and mortality resulting from mediastinitis, abscess formation, or sepsis. Postoperative patients complaining of cervical, thoracic, or epigastric pain, fever, dysphagia, or respiratory distress may therefore require an emergent esophagogram. At our institution, esophagograms are routinely performed between the sixth and eighth postoperative days because some patients with esophageal perforation are asymptomatic and others have delayed leaks. Mildly delayed leaks (postoperative days 7-21) are often caused by ischemia at a staple line.




Figure 27-1


Esophagogastrectomy with leak near esophagogastric anastomosis.

Spot radiograph centered at the esophagogastric anastomosis shows a 3-cm long track of barium arising from the left anterolateral wall of the anastomosis ( small arrow ). The track extends to the left and is just entering ( large arrow ) a mediastinal drain.


Edema, hemorrhage, and spasm at an anastomosis are the most common causes of obstruction in the early postoperative period. This obstruction usually resolves within 1 to 2 weeks after surgery. Obstruction may also occur when the viscus used as the esophageal substitute passes through the diaphragm ( Fig. 27-2 ). In the late postoperative period, obstruction is usually caused by a benign stricture related to a healed anastomotic leak, ischemia at the anastomosis, or chronic gastroesophageal reflux. Other patients may have recurrent cancer or a tight diaphragmatic hiatus as the cause of a narrowing.




Figure 27-2


Postoperative obstruction after esophagogastrectomy.

There is tapered narrowing of the stomach ( large arrow ) where it passes through the diaphragm. Below the diaphragm, twisting of the stomach is manifested radiographically by gastric folds ( small arrows ) radiating toward the area of narrowing. The stomach proximal to the obstruction shows dilation, delayed emptying of barium, and retained debris ( open arrow ).

(From Rubesin SE, Beatty SM: The postoperative esophagus. Semin Roentgenol 39:401–410, 1994.)


Esophageal dysmotility, delayed gastric emptying caused by pylorospasm or gastric atony, or diarrhea may be the result of manipulation, damage, or intentional surgical resection of the vagus nerve. Vocal cord paralysis or dysphagia with abnormal motility of the inferior constrictor muscles or proximal esophageal muscles may result from recurrent laryngeal injury.


Any form of esophageal surgery that disrupts the lower esophageal sphincter may result in gastroesophageal reflux. An antireflux procedure may be included as part of the esophagogastric anastomosis to prevent postoperative gastroesophageal reflux. Complications of postoperataive gastroesophageal reflux include aspiration, reflux esophagitis, stricture formation, Barrett’s esophagus, and adenocarcinoma arising in Barrett’s esophagus.


The thoracic duct may also be damaged during surgery. The thoracic duct passes superiorly, anterior to the spine, between the aorta and azygos vein. At the level of the T5 vertebral body, the thoracic duct crosses behind the esophagus and then continues cranially along the left side of the esophagus. Although uncommon, thoracic duct damage may result in chylothorax or chylous ascites.


Early postoperative complications may be manifested by a variety of findings on chest and abdominal radiographs. A dilated viscus with air-fluid levels should suggest gastric outlet obstruction when the stomach is used to replace the esophagus. Pneumomediastinum, cervical or subcutaneous emphysema, a widened mediastinum, or a rapidly enlarging pleural effusion should suggest anastomotic breakdown and perforation. Nevertheless, chest and abdominal radiographs may be normal in patients with perforation.


Depending on the nature of the surgery and status of the patient, the postoperative radiologic examination should be tailored to demonstrate suspected complications. Barium and water-soluble contrast agents each have advantages and disadvantages in evaluating patients during the early postoperative period. This subject is discussed in detail in Chapters 1 and 17 . Briefly, water-soluble contrast agents should be used during the early postoperative period to rule out a perforation or anastomotic leak into the mediastinum or pleural space. If no water-soluble contrast medium is seen to extravasate from the esophagus on initial spot images, high-density barium should then be given for a more detailed examination. Barium or low-osmolality, water-soluble contrast agents such as iohexol (Omnipaque) may be used as the primary contrast agent if aspiration or an esophageal-airway fistula is suspected.




Gastroesophageal Reflux and Hiatal Hernia


Patients with gastroesophageal reflux may undergo surgery because of intractable reflux esophagitis, peptic strictures, or Barrett’s esophagus. With most of these surgical procedures, the crura are dissected, the esophagus is mobilized, the vagus nerves are preserved, the hiatal hernia is reduced, the diaphragm is repaired, and the intra-abdominal esophagus is restored. A variable portion of gastric fundus is usually wrapped around the proximal stomach.


Normal Postoperative Appearances


In a Nissen fundoplication, the gastric fundus is loosely wrapped 360 degrees around the proximal stomach to create an antireflux valve. The Nissen fundoplication wrap normally appears as a 2- to 3-cm fundal mass, with a smooth contour and surface ( Fig. 27-3 ). If the patient drinks barium in a recumbent, steep oblique, or lateral position, the lumen is shown to pass through the center of the fundoplication wrap. The smooth symmetric wrap and its consistent relationship with the lumen readily differentiates a fundoplication wrap from a true tumor in the fundus.




Figure 27-3


Normal Nissen fundoplication.

The fundoplication wrap is seen as a smooth-surfaced, well-defined mass ( arrows ) in the gastric fundus.


In a Belsey Mark IV repair, the gastric fundus is sutured to the intra-abdominal esophagus, creating an acute esophagogastric junction angle (angle of His); a 270-degree fundoplication wrap is then created. The gastric wrap of a Belsey Mark IV repair produces a smaller defect than a Nissen fundoplication. Two distinct angles are formed passing through the 270-degree fundoplication. The intra-abdominal esophagus has a shallow upper angle where the esophagus, fundus, and diaphragm are sutured together and a lower angle where the stomach is pulled upward toward the esophagus.


A less than circumferential wrap may be made anteriorly or posteriorly, especially in patients with esophageal dysmotility and poor esophageal clearance. Wraps may be made loosely ( Fig. 27-4 ), especially if the surgery is performed laparoscopically. Knowledge of the exact surgical technique performed is helpful for radiologic interpretation.




Figure 27-4


Loose fundoplication wrap.

The loose fundoplication wrap is filled with barium and is manifested as a white/barium-filled rectangular structure crossing the gastric cardia ( white arrows ). The wall of the fundoplication wrap is seen as a thick, linear radiolucency ( black arrows ) adjacent to the rectangular barium collection.

(From Rubesin SE, Levine MS: Postoperative esophagus. In Levine MS: Radiology of the Esophagus. Philadelphia, WB Saunders, 1989, pp 267–290.)


Complications


Complications related directly to surgery include pneumothorax and pneumomediastinum. Acute hemorrhage usually arises from the short gastric vessels ligated at surgery or is related to operative injury of the spleen or liver. Instrumental perforation of the esophagus or stomach may not be detected during surgery and may lead to a left upper quadrant abscess. Late esophageal perforation may be caused by ischemia or diathermy injury.


Obstruction


During the early postoperative period, edema of the fundoplication wrap may cause transient dysphagia. This complication may be manifested on esophagograms by a large, smooth fundal mass associated with smooth, tapered narrowing of the intra-abdominal esophagus and delayed emptying of contrast material ( Fig. 27-5 ). The edema usually subsides within 1 to 2 weeks; a follow-up esophagogram demonstrates a much smaller defect in this region because of the normal fundoplication wrap.




Figure 27-5


Postoperative wrap edema.

One day after laparoscopic fundoplication wrap surgery, the patient had chest pain and difficulty handling her secretions. A low-magnification radiograph shows a large volume of gas (carbon dioxide) underneath the left and right hemidiaphragms. The esophagus just proximal to the fundoplication is a tight 3 mm in luminal diameter ( arrows ). The thoracic esophagus is dilated and showed delayed esophageal emptying. One week later, the esophageal obstruction caused by edema of the fundoplication wrap had resolved. The esophageal narrowing increased to about 8 mm.


Some patients may have persistent narrowing at the fundoplication, causing dysphagia or the so-called gas bloat syndrome, with upper abdominal fullness and an inability to belch after meals. Patients may also complain of an inability to vomit and increased flatulence. In such cases, esophagograms may demonstrate fixed narrowing of the lumen as a result of a tight fundoplication wrap ( Fig. 27-6 ) or excessive closure of the esophageal hiatus of the diaphragm. It is sometimes difficult to distinguish a persistent reflux-induced distal esophageal stricture from a tight wrap. Examination of the preoperative images is helpful.




Figure 27-6


Persistent obstruction by a tight Nissen fundoplication wrap.

A. Spot radiograph obtained with patient in an erect position shows that the lumen of the stomach is mildly narrowed (measuring ≈6 mm in luminal diameter; arrows ) by a tight fundoplication wrap ( arrows ). B. Spot radiograph obtained while the patient is drinking in a right anterior oblique position shows a narrowed distal esophagus ( thin arrows ) and large fundoplication wrap ( arrowheads ).


Recurrent Hiatal Hernia and Gastroesophageal Reflux


Complete disruption of the fundoplication sutures and crural repair is manifested radiographically by a recurrent hiatal hernia and gastroesophageal reflux, without visualization of the fundoplication wrap ( Fig. 27-7 ). Partial disruption of the fundoplication sutures may be manifested by a partially intact wrap associated with one or more outpouchings from the gastric fundus ( Fig. 27-8 ) or by an hourglass appearance of the stomach as the fundus slips through the fundoplication. An hourglass stomach may also be caused by inappropriate placement of the fundoplication around the gastric body. Finally, disruption of the diaphragmatic sutures (but not the fundoplication sutures) may result in a recurrent hiatal hernia, with continued demonstration of an intact fundoplication wrap ( Fig. 27-9 ). A paraesophageal hernia may occur at diaphragmatic repair breakdown ( Fig. 27-10 ).




Figure 27-7


Breakdown of fundoplication wrap and recurrent hiatal hernia.

Multiple gastric outpouchings ( open arrows ) are seen above the level of the diaphragm ( large black arrow ). The expected mass of the fundoplication wrap is not present in the gastric fundus. A focal peptic stricture is also seen at the gastroesophageal junction ( small black arrow ).

(From Rubesin SE, Levine MS: Postoperative esophagus. In Levine MS: Radiology of the Esophagus. Philadelphia, WB Saunders, 1989, pp 267–290.)



Figure 27-8


Partial breakdown of fundoplication wrap.

The fundal wrap is partially intact ( black arrows ) but does not encircle the distal esophagus. A small fundal outpouching is present ( white arrow ). Barium is seen in the distal esophagus because of gastroesophageal reflux.



Figure 27-9


Recurrent hiatal hernia resulting from disruption of sutures closing the esophageal hiatus of the diaphragm.

A small hiatal hernia ( long arrows ) lies above the diaphragm. An intact fundoplication wrap ( short arrows ) is manifest as a radiolucent filling defect in the barium pool within the hernia and as a “mass” surrounding the distal esophagus.



Figure 27-10


Paraesophageal herniation of gastric fundus after breakdown of diaphragmatic repair.

Low magnification image demonstrating a large paraesophageal herniation of the gastric fundus (PH) above the left hemidiaphragm ( arrow ). The hernia is next to the distal esophagus (E).




Benign Strictures


Benign esophageal strictures may be treated by various surgical and nonsurgical procedures, including esophageal bougienage, fluoroscopically controlled balloon dilation, endoscopically placed esophageal stents, and esophageal replacement with a gastric tube, jejunal graft, or colonic interposition. The site, extent, and cause of the stricture affect the therapeutic choice. Peroral balloon or endoscopic dilation of strictures under fluoroscopic guidance is an effective alternative to esophageal bougienage. This procedure has a lower risk of perforation and a longer symptom-free interval than esophageal bougienage.


Surgery is usually required for the treatment of lye strictures. Esophageal replacement surgery may also be performed on patients with intractable strictures caused by gastroesophageal reflux disease.

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Jun 23, 2019 | Posted by in GASTROINTESTINAL IMAGING | Comments Off on Postoperative Esophagus
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