Hypertensive Emergency Presenting With Isolated Cranial Nerve III Palsy and Subsequent Intracranial Hemorrhage.

Hypertensive emergencies present as a life-threatening condition characterized by severely elevated blood pressure with evidence of acute end-organ damage. The most common neurological presentations include ischemic stroke, encephalopathy, and intracranial hemorrhage; however, isolated cranial nerve palsies are a rare occurrence. We present a case of a 72-year-old female with a history of chronic hypertension who presented to the emergency department at Chino Valley Medical Center with a one-week history of malaise, headache, hypertension, and right eye pain. She subsequently developed a right-sided cranial nerve III palsy during hospitalization. CT angiography demonstrated greater than 90% stenosis of the left carotid bulb without evidence of aneurysm. MRI showed bilateral basal ganglia and thalamic T2 hyperintensities consistent with hypertensive encephalopathy. Despite escalating antihypertensive therapy, the patient experienced an abrupt neurological decline and cardiopulmonary arrest. Repeat CT imaging revealed a multi-compartment intracranial hemorrhage with a 10 mm midline shift, with the hemorrhage pattern most consistent with rupture of a previously occult aneurysm not visualized on initial CTA. This case highlights an atypical presentation of hypertensive emergency with an isolated cranial nerve III palsy and underscores the importance of considering aneurysmal pathology even when early vascular imaging is unrevealing. Recognition of such atypical presentations is critical for timely diagnosis and prevention of devastating neurological outcomes.