Cavernous Sinus: Critical Contents
The cavernous sinus is a paired dural venous sinus located on either side of the sella turcica. It is a frequent site of clinical concern due to the high density of vital structures passing through it.
| Location | Structures |
|---|---|
| Within the sinus (Medial) | Internal Carotid Artery (with sympathetic plexus) and CN VI (Abducens). |
| Within the lateral wall | CN III (Oculomotor), CN IV (Trochlear), CN V1 (Ophthalmic), and CN V2 (Maxillary). |
High-Yield Clinical Notes:
- Cavernous Sinus Thrombosis: Often secondary to infections in the “danger triangle” of the face (drained by facial vein → superior ophthalmic vein → cavernous sinus).
- Clinical Presentation: Presents with ophthalmoplegia (CN III, IV, VI palsies) and sensory loss in the V1/V2 distribution.
- Key Differentiator: CN VI is the only cranial nerve that runs inside the sinus with the internal carotid artery, making it the first nerve typically affected by mass effect or internal carotid pathology.