Carotid Space Overview

Summary Thoughts: Carotid Space

The carotid spaces (CSs) are paired tubular spaces that traverse the suprahyoid neck (SHN) and infrahyoid neck (IHN) just lateral to the retropharyngeal space (RPS). Another term for the CS is the retrostyloid parapharyngeal space (PPS). The CS is enveloped by the carotid sheath , which is made up of all 3 layers of deep cervical fascia . The SHN CS contains the internal carotid artery (ICA), internal jugular vein (IJV), and cranial nerves (CN) IX-XII. The IHN CS has within it only the common carotid artery (CCA), IJV, and the vagus nerve (CNX) trunk.

A SHN CS mass displaces the anterior PPS fat anteriorly as it enlarges. Often the ICA is also displaced anteriorly by an enlarging SHN CS mass. An IHN CS mass engulfs the CCA or splays the carotid bifurcation (carotid body paraganglioma).

Important CS tumors include paraganglioma, schwannoma, neurofibroma, and sympathetic chain schwannoma. The internal jugular nodal chain is in close proximity to the superficial margin of the CS. As a result, when squamous cell carcinoma (SCCa) metastatic nodes undergo extranodal spread, they may involve the adjacent carotid artery and vagus nerve.