Danger space

The danger space lies behind the true retropharyngeal space, and courses more inferiorly than the true retropharyngeal space, running into the posterior mediastinum until the level of the diaphragm. The Danger space connects the deep cervical spaces to the mediastinum. 

Boundaries:

• superiorly: clivus
• inferiorly: posterior mediastinum at the level of the diaphragm
• anteriorly: alar fascia
• posteriorly: prevertebral fascia