Does a patient presenting with stroke-like symptoms and a 2 mm left posterior communicating artery (PCA) aneurysm warrant a neurosurgery consult?

Management of a 2mm Left Posterior Communicating Artery Aneurysm in a Patient with Stroke-Like Symptoms

A patient presenting with stroke-like symptoms and a 2mm left posterior communicating artery aneurysm warrants an urgent neurosurgical consultation.

Initial Management and Rationale

• Patients with aneurysmal subarachnoid hemorrhage (SAH) should be treated as a medical emergency and evaluated immediately by physicians with expertise in stroke management 1
• Patients with SAH should have an urgent consultation with a neurosurgeon due to the high early risk for bleeding 1
• Patients should be managed in centers with neurosurgical expertise that treat aneurysms regularly using both endovascular and surgical techniques 1

Diagnostic Workup

• Patients with suspected SAH should have a non-contrast CT scan immediately on arrival to hospital to confirm the diagnosis 1
• If CT is negative but clinical suspicion remains high, a lumbar puncture and CSF analysis should be performed 1
• Vascular imaging of the brain (preferably high-quality CTA) should be performed to investigate the cause of hemorrhage 1
• The severity of SAH should be determined using validated scales such as World Federation of Neurological Surgeons (WFNS), GCS, Hunt and Hess scale, NIHSS, and Fisher Scale 1

Management Considerations for Small Aneurysms

• While the aneurysm is small (2mm), its location on the posterior communicating artery warrants attention as posterior circulation aneurysms carry higher risks 1
• Even small unruptured aneurysms can cause stroke symptoms through thromboembolic mechanisms 2, 3
• There is documented evidence of small infundibular dilations evolving into true aneurysms over time, suggesting the need for follow-up even for small aneurysms 4

Treatment Decision-Making

• The decision for intervention should consider:

  • The patient's neurological status and stroke symptoms 1
  • The risk of aneurysm rupture, which is influenced by size, location, and patient factors 1
  • The technical feasibility of treatment options 1

• For posterior circulation aneurysms, endovascular coiling may be preferred over surgical clipping based on subgroup analyses from clinical trials 1

• True posterior communicating artery aneurysms (arising from the PCoA itself rather than at the junction with the internal carotid artery) are rare but can be successfully treated with endovascular techniques 5

Neurosurgical Consultation Importance

• Neurosurgical expertise is crucial for evaluating both endovascular and surgical options to determine the optimal treatment strategy 1
• The evaluation of the ruptured aneurysm for endovascular and surgical options by specialists with expertise in both modalities is necessary to optimally evaluate the relative risks and benefits of each treatment strategy 1
• Early consultation facilitates planning for potential interventions and ensures appropriate monitoring 1

Follow-up Recommendations

• If immediate intervention is not pursued, close follow-up with serial imaging is essential 4
• For small aneurysms that are not treated, follow-up MRI (e.g., in yearly intervals) is advised, especially for those with a diameter of 3 mm or more 4
• Patients with other risk factors such as other aneurysms, documented de novo aneurysm formation, or familial occurrence of aneurysms may require more stringent follow-up 4

Important Caveats

• Even small aneurysms in the posterior circulation can carry significant risks 1
• The presence of stroke-like symptoms in conjunction with an aneurysm raises concern for possible thromboembolic complications from the aneurysm 2, 3
• Delaying neurosurgical consultation could potentially increase the risk of adverse outcomes if the aneurysm is the source of the patient's symptoms 1