Anatomy of the Temporal Fossa
Overview and Boundaries
The temporal fossa is a complex anatomical region located on the lateral aspect of the skull, bounded superiorly by the superior temporal line, inferiorly by the zygomatic arch, anteriorly by the frontal and zygomatic bones, and posteriorly by the temporal bone. 1
The temporal fossa can be conceptualized as five discrete radiographically defined regions that are clinically relevant for understanding disease spread 1:
- Connective tissue layer - the superficial fascial plane 1
- Compartment of the superficial fat pad - located beneath the connective tissue 1
- Compartment of the deep fat pad - situated deeper within the fossa 1
- Compartment of the temporal muscle (superior recess of the suprazygomatic masticator space) - housing the temporalis muscle 1
- Subperiosteal zone - the deepest layer adjacent to bone 1
Key Anatomical Structures
Muscular Components
The temporalis muscle is the principal muscular structure of the temporal fossa, with its tendon inserting on the coronoid process of the mandible within the infratemporal fossa. 2 The temporal muscle receives vascular supply from the anterior and posterior branches of the deep temporal artery, with occasional presence of a middle deep temporal artery 2.
Bony Architecture
The floor of the temporal fossa is formed by portions of the frontal, parietal, temporal, and sphenoid bones 1. The temporal fossa communicates inferiorly with the infratemporal fossa, which represents a continuation of the temporal fossa between the internal surface of the zygoma and the external surface of the temporal bone and greater wing of the sphenoid bone, sitting deep to the mandibular ramus 2.
Neurovascular Relationships
The temporal fossa contains important interconnections with surrounding anatomical regions 1:
- Tortuous connections exist between the scalp, posterior neck, eyelid, face, and the suprazygomatic masticator space - these pathways are clinically significant for understanding disease spread 1
- The maxillary artery, a terminal branch of the external carotid artery, originates at the neck of the mandible and courses through this region 2
- The pterygoid venous plexus provides venous drainage 2
Clinical Relevance
Surgical Access Considerations
The temporal fossa serves as a critical surgical corridor for accessing deeper skull base structures 3, 4. The infratemporal fossa approach, which utilizes the temporal fossa as an access route, provides exposure to the lateral skull base, jugular foramen, and infralabyrinthine compartments of the temporal bone 3, 4.
Key surgical landmarks include the lateral pterygoid muscle, which serves as the principal structure for understanding relationships within the infratemporal fossa. 2 The approach may require zygomatic osteotomy and mobilization of the lateral orbital rim for adequate exposure 4.
Pathological Considerations
The temporal fossa can be affected by various pathologies including benign and malignant tumors that may extend from or into adjacent spaces 2. Understanding the five discrete compartments of the temporal fossa is essential for predicting patterns of disease spread on imaging studies 1.
Imaging studies, particularly high-resolution MRI and CT, are superior to anatomic descriptions alone for understanding the complex interconnections and disease spread patterns within the temporal fossa. 1