ORBITAL APEX SYNDROME

Question 1

The orbital apex

Answer 1

is the most posterior part of the pyramidalshaped orbit at the craniofacial junction.
* OA includes the tendinous ring where the rectus EOMs originate and also the entry of neuro-vascular structures transmitted from the intracranial compartment into the orbit through bony apertures (optic canal, SOF and inferior orbital fissure)

Question 2

OAS signs

Answer 2

OAS is characterized by the involvement of CNs II (vision affected), III, IV and VI
* Vision loss (if CN II involvement is present), optic neuropathy and ophthalmoplegia.
More closer to eye = more nerves affected (1+) + more likely to get proptosis

Question 3

aeitiology OAS

Answer 3

Nasopharyngeal carcinoma, hematological tumors, neural tumors, lymphoma, metastasis or middle cranial fossa (near the apex of the orbit), inflammatory causes such as idiopathic orbital inflammation, collagen vascular disease, sarcoidosis, systemic lupus, giant cell arteritis, thyroid disease, iatrogenic causes (following sinonasal surgery), orbital apex fracture, vascular events like carotid aneurysm or trauma