Incidental 9mm Fusiform Aneurysm of the Left Internal Carotid Artery in a Patient with Hypertensive Urgency

Case at a Glance

A 37-year-old female presented to the emergency department with hypertensive urgency and acute dizziness, leading to the incidental discovery of a 9 mm fusiform aneurysm in her left internal carotid artery. This case highlights the diagnostic evaluation and management considerations for incidentally found fusiform aneurysms, particularly in the context of significant risk factors like severe hypertension and a strong family history.

Patient's Story

A 37-year-old female with a history of several unspecified chronic conditions presented to the emergency department after a sudden onset of severe dizziness. She also reported a background of chronic, non-specific symptoms including bilateral hand numbness, generalized edema, and persistent fatigue. The patient has a significant family history of cerebrovascular disease, with both a paternal aunt and uncle having been treated for multiple intracranial aneurysms.

Initial Assessment

Upon presentation to the emergency department, the patient was found to be in a state of hypertensive urgency with a blood pressure of 221/122 mmHg. Given the acute neurological symptom (dizziness) and the markedly elevated blood pressure, an urgent non-contrast computed tomography (CT) scan of the head was performed to rule out an acute intracranial event such as hemorrhage.

The Diagnostic Journey

The head CT did not show any evidence of acute hemorrhage but incidentally revealed a 9 mm fusiform dilatation of the left internal carotid artery. The patient was medically stabilized and discharged with instructions for strict blood pressure monitoring and control. An urgent outpatient Magnetic Resonance Angiogram (MRA) was scheduled to further delineate the aneurysm's morphology, precise location (intracranial vs. extracranial segment), and relationship to adjacent structures.

Final Diagnosis

Incidental 9 mm fusiform aneurysm of the left internal carotid artery, discovered during a workup for hypertensive urgency and dizziness.

Treatment Plan

The patient was referred for a neurosurgical consultation to discuss management strategies pending the MRA results. The planned discussion would cover:

1. Observation vs. Intervention: While many small aneurysms are monitored, a 9 mm aneurysm is considered intermediate-to-large and often warrants treatment consideration. The final decision would depend heavily on the precise location and characteristics revealed by the MRA.
2. Symptom Correlation: It was determined that the presenting dizziness and hypertensive state were most likely unrelated to the unruptured aneurysm. Instead, chronic, severe hypertension is a major risk factor for the formation and potential growth of the aneurysm itself. The discovery was therefore considered incidental.
3. Management of Fusiform Aneurysms: It was explained that fusiform aneurysms, which involve a circumferential bulge of the vessel wall, are managed differently than saccular ('berry') aneurysms. They are often ideal candidates for endovascular treatment using flow-diverting stents. This procedure involves placing a specialized stent across the aneurysm neck to reconstruct the parent artery, diverting blood flow away from the aneurysm sac and promoting its thrombosis.
4. Referral Pathway: A consultation with a cerebrovascular neurosurgeon was recommended. While endovascular specialists (who may be neurosurgeons, interventional radiologists, or neurologists) perform stent procedures, a neurosurgeon can offer both endovascular and open surgical options if required.

Outcome and Follow-up

The patient is awaiting her MRA to provide high-resolution imaging of the aneurysm. Following this, she will proceed with the neurosurgical consultation to establish a definitive treatment plan. The cornerstone of her long-term management, regardless of whether the aneurysm is treated or monitored, will be aggressive and consistent control of her blood pressure to mitigate the risk of aneurysm growth or rupture.