PITUITARY APOPLEXY PRESENTING AS AN ISOLATED OCULOMOTOR NERVE PALSY
1 East Avenue Medical Center
Isolated third nerve palsy is produced when a lesion occurs along the tract of the oculomotor nerve from the nucleus located in the midbrain, to the fascicles exiting the medial portion of the midbrain, coursing through the subarachnoid space into the lateral wall of the cavernous sinus, until it reaches its target muscles after it enters the superior orbital fissure. It can be caused by numerous factors such as ischemia, hemorrhage, compression by tumors, and others. It is commonly associated with other cranial nerve palsies (IV and VI), as it is closely related to the other cranial nerves especially in the cavernous sinus where a pituitary apoplexy usually expands into. Hence, an isolated third nerve palsy is an uncommon presentation of a sellar mass, such as a pituitary apoplexy. This is a case of a 56 year-old male who presents with sudden onset of severe headache associated with ptosis of the left eye, followed by diplopia at the Emergency room of East Avenue Medical Center, initially managed as a case of PCOM aneurysm, but was later discovered to be a case of Pituitary Apoplexy.
The combination of headache, visual disturbances, and ophthalmoplegia are commonly identified as symptoms of neurological emergencies such as a ruptured posterior communicating artery aneurysm, but it is important to keep an open mind and consider other differential diagnoses such as pituitary apoplexy, as shown in this case.