Comparison of the Orbitozygomatic and Transmandibular Approaches to the Infratemporal Fossa

Area of Science:

• Neurosurgery
• Skull Base Anatomy
• Surgical Approaches

Background:

• The infratemporal fossa (ITF) is a complex anatomical region crucial for skull base surgery, often involved in neoplastic lesion extension.
• Surgical access to the ITF presents significant technical challenges.
• The orbitozygomatic (OZ) and transmandibular (TM) approaches provide different perspectives for ITF exploration.

Purpose of the Study:

• To anatomically compare the microsurgical fields, advantages, and limitations of the OZ and TM approaches for accessing the ITF.
• To delineate the optimal use of each surgical technique for ITF pathologies.

Main Methods:

• Dissection of 10 sides of silicone-injected, formalin-fixed cadaveric heads using surgical microscopes.
• Standard OZ craniotomy followed by middle cranial fossa drilling and greater sphenoid wing resection to expose the ITF.
• Subsequent performance of the TM approach on the same cadavers to assess its additional exposure capabilities.

Main Results:

• The OZ approach provided wide exposure of the anterior and middle ITF with minimal brain retraction but limited access to the posterior ITF and specific neurovascular structures.
• The TM approach offered enhanced visualization of the middle and posterior ITF, with superior control of the maxillary artery and exposure of deep neurovascular elements.
• Combining both approaches yielded a complementary panoramic view of the ITF.

Conclusions:

• The OZ approach is best suited for anterior and middle ITF lesions with orbital or cavernous sinus involvement.
• The TM approach is more effective for posterior ITF pathologies requiring extensive vascular and neural access.
• A combined strategy may provide a tailored approach for complex ITF skull base surgeries.