Computed Tomography Imaging of Iatrogenic Esophageal Injuries

ABSTRACT

Knowledge of iatrogenic esophageal injuries is important given the variety of etiologies, including medical instrumentation (eg, endoscopes), radiotherapy, and anticoagulation. The clinical presentation and imaging findings of esophageal injuries depend on the mechanism and location of the injury. Imaging modalities commonly used for the evaluation of esophageal injuries include esophagram and computed tomography. Esophageal injuries should be considered in patients with acute chest symptoms. Recognizing an unsuspected esophageal injury on imaging can be critical to reaching the correct diagnosis given their nonspecific symptomatology. This review article highlights various iatrogenic esophageal injuries and their appearance on computed tomography imaging.

Chest CT for the Diagnosis of Pediatric Esophageal Foreign Bodies

Foreign body ingestion is a common problem in children. Radiography is the mainstay of imaging, but many radiolucent items go undetected without further imaging by fluoroscopic esophagram. While studies in adults support the use of computed tomography (CT) for esophageal foreign body ingestion, CT has historically not been used in children given the typically higher radiation doses on CT compared with fluoroscopy. In distinction to an esophagram, CT does not require oral contrast nor presence of an onsite radiologist and can be interpreted remotely. At our institution, a dedicated CT protocol has been used for airway foreign bodies since 2015. Given the advantages of CT over esophagram, we retrospectively reviewed institutional radiation dose data from 2017 to 2020 for esophagrams, airway foreign body CT (FB-CT), and routine CT Chest to compare effective doses for each modality. For ages 1+ years, effective dose was lowest using the FB-CT protocol; esophagram mean dose showed the most variability, and was over double the dose of FB-CT for ages 5+ years. Routine CT chest doses were uniformly highest across all age ranges. Given these findings, we instituted a CT foreign body imaging protocol as the first-line imaging modality for radiolucent esophageal foreign body at our institution.

Clinical Application of Oral Meglumine Diatrizoate Esophagogram in Screening for Esophageal Fistula During Radiotherapy or Chemoradiotherapy for Esophageal Cancer

Background: This study aimed to investigate the specificity and sensitivity of oral meglumine diatrizoate esophagogram in screening for esophageal fistula during radiotherapy or chemoradiotherapy for esophageal cancer and determine if early detection and intervention could improve the prognosis of esophageal fistulas.

Methods: Esophageal cancer patients undergoing radiotherapy or chemoradiotherapy were included. Weekly oral meglumine diatrizoate esophagograms were performed to screen for esophageal fistulas during radiotherapy. When an esophageal fistula was detected, fibroesophagoscopy and computed tomography (CT) were used for confirmation; once confirmed, radiotherapy was discontinued, and the patient received intervention. The esophagogram results were reviewed weekly to assess the recovery of the esophageal fistula. If the fistula was healed, the patient resumed and completed radiotherapy.

Results: A total of 206 patients with cancer of the esophagus undergoing chemotherapy/radiotherapy were included. During radiotherapy, 10 cases of esophageal fistula were detected or suspected based on the oral meglumine diatrizoate esophagography findings, and eight of those cases were confirmed by CT and esophagoscopy. All patients with esophageal fistula received intervention; among them, 62.5% (5/8) recovered after 1 to 2 weeks of treatment and continued radiotherapy to completion. The sensitivity and specificity of oral meglumine diatrizoate esophagography in screening for esophageal fistulas during radiotherapy or chemoradiotherapy were 100 and 98.9%, respectively. The median survival period of patients with esophageal fistulas was 6.4 months.

Conclusion: Oral meglumine diatrizoate esophagography has high sensitivity and specificity in screening for esophageal fistulas during radiotherapy or chemoradiotherapy with minimal side effects. Early diagnosis and timely intervention can significantly improve the prognosis and prolong the survival period of patients.

Trial Registration: Chictr.org.cn, Identifier: ChiCTR-DDD-17012617. Registered on September 7, 2017. The first participant was enrolled on September 25, 2017. http://www.chictr.org.cn/showproj.aspx?proj=21526.

Diagnostic Utility of CT and Fluoroscopic Esophagography for Suspected Esophageal Perforation in the Emergency Department

OBJECTIVE. We evaluated the diagnostic utility of CT in emergency department (ED) patients with suspected esophageal perforation and assessed whether subsequent fluoroscopic esophagography is necessary. MATERIALS AND METHODS. This retrospective study included consecutive adult patients presenting to an urban academic tertiary care ED from January 1, 2000, to August 31, 2017, who underwent CT and fluoroscopic esophagography within 1 calendar day (< 27 hours) of each other for suspected esophageal perforation. The use of oral or IV contrast material and the CT findings (i.e., pneumomediastinum, pleural effusion, pneumothorax, unexplained mediastinal fluid or stranding, esophageal wall air or frank esophageal wall disruption, or extraluminal oral contrast material) were documented. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Surgical or procedural intervention results or clinical follow-up results were the reference standard. RESULTS. One hundred three patients met the inclusion criteria. Sensitivity, specificity, PPV, and NPV for diagnosing esophageal perforation were 100.0%, 79.8%, 32.1%, and 100.0%, respectively, with CT and 77.8%, 98.9%, 87.5%, and 97.9% with fluoroscopic esophagography. Combining CT and fluoroscopic esophagography did not improve sensitivity, specificity, PPV, or NPV relative to using CT alone. The true-positive esophageal perforation rate was 8.7% for CT and 6.8% for fluoroscopic esophagography. When CT showed only pneumomediastinum (n = 51) or no pneumomediastinum (n = 14), the NPV of CT was 100.0%. CT with oral contrast material had a PPV of 38.5%, whereas CT without oral contrast material had a PPV of 26.7%. CONCLUSION. CT has a high NPV similar to that of fluoroscopic esophagography and has greater sensitivity than fluoroscopic esophagography for diagnosing suspected esophageal perforation. Fluoroscopic esophagrams do not provide additional information that changes clinical management beyond the information that CT provides. In ED patients with suspected esophageal perforation, CT with oral contrast material should be considered the initial imaging examination and can obviate fluoroscopic esophagography.

Esophageal Foreign Bodies and Obstruction in the Emergency Department Setting: An Evidence-Based Review

BACKGROUND

Patients with esophageal foreign bodies or food bolus impaction may present to the emergency department with symptoms ranging from mild discomfort to severe distress. There is a dearth of emergency medicine-focused literature concerning these conditions.

OBJECTIVE OF THE REVIEW

This narrative review provides evidence-based recommendations for the assessment and management of patients with esophageal foreign bodies and food bolus impactions.

DISCUSSION

Esophageal foreign bodies and food bolus impaction are common but typically pass spontaneously; however, complete obstruction can lead to inability to tolerate secretions, airway compromise, and death. Pediatric patients are the most common population affected, while in adults, edentulous patients are at greatest risk. Foreign body obstruction and food bolus impaction typically occur at sites of narrowing due to underlying esophageal pathology. Diagnosis is based on history and examination, with most patients presenting with choking/gagging, vomiting, and dysphagia/odynophagia. The preferred test is a plain chest radiograph, although this is not required if the clinician suspects non-bony food bolus with no suspicion of perforation. Computed tomography is recommended if radiograph is limited or there are concerns for perforation. Management requires initial assessment of the patient's airway. Medications evaluated include effervescent agents, glucagon, calcium channel blockers, benzodiazepines, nitrates, and others, but their efficacy is poor. Before administration, shared decision making with the patient is recommended. Endoscopy is the intervention of choice, and medications should not delay endoscopy. Early endoscopy for complete obstruction is associated with improved outcomes.

CONCLUSIONS

This review provides evidence-based recommendations concerning these conditions, focusing on evaluation and management.

Imaging of thoracic hernias: types and complications

Thoracic hernias are characterised by either protrusion of the thoracic contents outside their normal anatomical confines or extension of the abdominal contents within the thorax. Thoracic hernias can be either congenital or acquired in aetiology. They can occur at the level of the thoracic inlet, chest wall or diaphragm. Thoracic hernias can be symptomatic or fortuitously discovered on imaging obtained for other indications. Complications of thoracic hernias include incarceration, trauma and strangulation with necrosis. Multiple imaging modalities are available to evaluate thoracic hernias. Radiographs usually offer the first clue to the diagnosis. Upper gastrointestinal radiography can identify bowel herniation and associated complications. CT and occasionally MR can be useful for further evaluation of these abnormalities, accurately identifying the type of hernia, its contents, associated complications, and provide a roadmap for surgical planning. In this article, we review the different types of thoracic hernias and the role of imaging in the evaluation of these hernias. TEACHING POINTS: • Protrusion of lung contents beyond the anatomic confines of the thorax constitutes a hernia. • Complications of thoracic hernias include incarceration, trauma and strangulation with necrosis. • Multiple imaging modalities are available to evaluate thoracic hernias. • CT is the imaging modality of choice for identifying thoracic hernias and their complications. • Imaging can provide a roadmap for surgical planning.

Imaging of iatrogenic oesophageal injuries using optimized CT oesophageal leak protocol: pearls and pitfalls

Iatrogenic injury to the oesophagus is a serious complication which is increasingly seen in clinical practice secondary to expansion and greater acceptability of surgical and endoscopic oesophageal procedures. Morbidity and mortality following such injury is high. This is mostly due to an inflammatory response to gastric contents in the mediastinum, and the negative intrathoracic pressures that may further draw out oesophageal contents into the mediastinum leading to mediastinitis. Subsequently, pulmonary complications such as pneumonia or abscess may ensue leading to rapid clinical deterioration. Optimized and timely cross-sectional imaging evaluation is necessary for early and aggressive management of these complications. The goal of this review is to make the radiologist aware of the importance of early and accurate identification of postoperative oesophageal injury using optimized CT imaging protocols and use of oral contrast. Specifically, it is critical to differentiate benign post-operative findings, such as herniated viscus or redundant anastomosis, from clinically significant postoperative complications as this helps guide appropriate management. Advantages and drawbacks of other diagnostic methods, such as contrast oesophagogram, are also discussed.

Esophagectomy and Gastric Pull-through Procedures: Surgical Techniques, Imaging Features, and Potential Complications

Esophagectomy takes the center stage in the curative treatment of local and local-regional esophageal cancer. It is a complex procedure with a high postoperative complication rate. When interpreting imaging studies, radiologists must understand the surgical techniques used and their potential complications. The most common surgical techniques are transthoracic esophagectomies, such as the Ivor Lewis and McKeown techniques, and transhiatal esophagectomy. Variations of these techniques include different choices of conduit (ie, stomach, colon, or jejunum) to serve in lieu of the resected esophagus. Postoperative imaging and accurate interpretation is vital in the aftercare of these patients. Chest radiographs, esophagrams, and computed tomographic images play an essential role in early identification of complications. Pulmonary complications and anastomotic leaks are the leading causes of postoperative morbidity and mortality secondary to esophagectomy. Other complications include technical and functional problems and delayed complications such as anastomotic strictures and disease recurrence. An esophagographic technique is described that is performed by using hand injection of contrast material into an indwelling nasogastric tube. Familiarity with the various types of esophagectomy and an understanding of possible complications are of utmost importance for radiologists and allow them to be key participants in the treatment of patients undergoing these complicated procedures.