Pituitary Apoplexy Without Chiasmal Compression Presenting With Radiographic Oculomotor Nerve Compression in a Prolactinoma: A Case Report

Pituitary apoplexy is a rare but potentially life-threatening complication of pituitary macroadenomas that classically presents with acute headache, visual field deficits, and signs of optic chiasm compression. However, atypical neuro-ophthalmologic presentations without chiasmal involvement may delay recognition and treatment. This report highlights an unusual presentation of pituitary apoplexy associated with radiographic oculomotor nerve compression secondary to cavernous sinus extension in a patient with prolactinoma. We report the case of a 29-year-old Hispanic woman who presented to the emergency department (ED) with acute right-sided headache, dizziness, and transient blurry vision after the reinitiation of cabergoline therapy for a previously diagnosed prolactinoma. The patient had a prolonged history of migraine-like headaches, amenorrhea, intermittent galactorrhea, and inconsistent adherence to dopamine agonist therapy due to medication intolerance. Magnetic resonance imaging (MRI) revealed a 1.5 cm right sellar macroadenoma with intralesional hemorrhage consistent with pituitary apoplexy. Imaging demonstrated extension into the right cavernous sinus with compression and lateral displacement of the oculomotor nerve, without contact or compression of the optic chiasm or optic nerves. Endocrine evaluation demonstrated hyperprolactinemia and secondary adrenal insufficiency. The patient underwent endoscopic transsphenoidal resection with subsequent clinical stabilization and normalization of prolactin levels. Pathology confirmed a lactotroph pituitary adenoma. This case highlights an atypical presentation of pituitary apoplexy without classic chiasmal syndrome and emphasizes the importance of recognizing cavernous sinus cranial neuropathy as a potential presenting feature. Clinicians should maintain suspicion for pituitary apoplexy in patients with prolactinoma presenting with acute headache and cranial nerve (CN) abnormalities, even in the absence of visual field defects or optic pathway compression.