The parapharyngeal space (or lateral pharyngeal space) is a potential space in the head and the neck. It has clinical importance in otolaryngology due to parapharyngeal space tumours and parapharyngeal abscess developing in this area.
Anatomical boundaries
The parapharyngeal space is shaped like an inverted pyramid, with the skull base superiorly, and the greater cornu (or greater horns) of the hyoid bone the apex, inferiorly.
The superior aspect is the base of skull, namely the sphenoid and temporal bones. It includes in this area the jugular and hypoglossal foramen and the foramen lacerum (through which the internal carotid artery passes superiorly across).
The medial aspect is made up of the pharynx.
Anteriorly it is bordered by the pterygomandibular raphe.
Posteriorly it is bordered by carotid sheath posteriolaterally and the retropharyngeal space posteriomedially.
The lateral aspect is more involved, and is bordered by the ramus of the mandible, the deep lobe of the parotid gland, the medial pterygoid muscle, and below the level of the mandible, the lateral aspect is bordered by the fascia of the posterior belly of digastric muscle.
These anatomical boundaries make it continuous with the retropharyngeal space. It also communicates with other cervical and cranial fascial spaces, as well as the mediastinum.
Divisions
The parapharyngeal space is divided into 2 parts by the fascial condensation called aponeurosis of Zuckerkandl and Testut, joining the styloid process to the tensor veli palatini. These two compartments are named the pre-styloid and post-styloid compartments.
Components
It includes the maxillary artery and ascending pharyngeal artery.[1]
1. glossopharyngeal nerve (IX) 2. vagus nerve (X) together with 3. internal carotid artery and 4. internal jagular vein in the carotid sheath 5. accessory nerve (XI) 6. hypoglossal (XII) 7. sympathetic trunk and superior cervical ggl of the trunk 8. ascending pharyngeal artery 9. deep cervical lymph nodes.