A 46-year-old woman presents to the emergency department for evaluation of fever, dysphagia, chest pain, and difficulty breathing which developed over the last 36 hours. Two days ago, she underwent endoscopic evaluation for medication-resistant gastroesophageal reflux disease. Vital signs are significant for a temperature of 102° F (38.9° C). Physical examination reveals a midline fluctuance in the posterior oropharynx concerning for abscess. Computed tomography of the neck and chest confirms the presence of abscess and evidence of superior mediastinitis.
Which of the following structures of the deep neck is most likely responsible for conveying infection from this patient’s abscess to the mediastinum?
E) Retropharyngeal space
The retropharyngeal space is the anterior-most potential space of the deep neck. It connects directly to the superior mediastinum and is bounded anteriorly by the buccopharyngeal fascia and posteriorly by the alar fascia. Infection in this space can also affect the internal jugular vein and cranial nerves of the medulla.
Answer choice A: Alar fascia, is incorrect. The alar fascia separates the retropharyngeal space anteriorly from the “danger space” posteriorly. Although infection can be conveyed through fascia, this patient’s infection is more likely to have traveled through the retropharyngeal space as it is closer to the source of infection.
Answer choice B: Pharyngeal mucosa, is incorrect. This is the layer that was most likely damaged during this patient’s recent endoscopy. Although penetration of this layer was necessary for abscess formation, it does not connect directly to the mediastinum.
Answer choice C: Prevertebral fascia, is incorrect. The prevertebral fascia separates the “danger space” from the prevertebral space. It is more posterior than the retropharyngeal space and less likely to have transmitted this patient’s infection from oropharynx to mediastinum.
Answer choice D: Prevertebral space, is incorrect. The prevertebral space is the most posterior space of the deep neck and extends to the coccyx. It is bounded anteriorly by the prevertebral fascia and posteriorly by the anterior spinal ligament.
Key Learning Point
The retropharyngeal space is the most anterior potential space of the deep neck. Infections transmitted through this space may affect the superior mediastinum, internal jugular vein, and cranial nerves of the medulla (IX, X, XI, and XII).
