Can a neuro‑interventionalist coil three intracranial aneurysms in a single endovascular session if they are anatomically accessible and the patient can tolerate the procedure?

Coiling Multiple Aneurysms in a Single Session

Yes, a neurointerventionalist can safely coil three intracranial aneurysms in a single endovascular session, provided the aneurysms are anatomically accessible and the patient can tolerate the procedure duration and contrast load. This approach has been demonstrated to be both safe and effective, with outcomes comparable to single-aneurysm procedures 1, 2.

Evidence Supporting Single-Session Treatment

Safety Profile

• Treatment of multiple aneurysms in one session carries low complication rates: In a large series of 167 patients undergoing single-stage coiling of multiple aneurysms (mean 2.1 aneurysms per patient), treatment-related morbidity was 1.8% and mortality was 0.6% per patient 2.
• No increased thromboembolic risk: A smaller series specifically examining same-session coiling of multiple aneurysms reported zero thromboembolic events, procedure-related ruptures, or mortality 1.
• Favorable functional outcomes: Among patients without subarachnoid hemorrhage treated in a single session, 97.7% achieved favorable outcomes (mRS 0-2) at discharge 2.

Technical Considerations

The key technical principles for same-session treatment include:

• Treat distal aneurysms first: This prevents catheter manipulation through freshly coiled proximal aneurysms, reducing the risk of coil displacement or thromboembolic complications 1.
• Use the same microcatheter when feasible: This reduces procedural time and vascular trauma 1.
• Prioritize the ruptured aneurysm if SAH is present: For patients with subarachnoid hemorrhage and multiple aneurysms, secure the ruptured aneurysm first, ideally within 24 hours 3.

Anatomic Suitability

Not all aneurysms are equally amenable to same-session treatment:

• Wide-necked aneurysms (neck >4mm) can be treated but may require adjunctive techniques like balloon remodeling or stent assistance, which increases procedural complexity and antiplatelet requirements 4, 5.
• Complete occlusion rates are similar to single procedures: Immediate complete occlusion was achieved in approximately 52% of aneurysms, with neck remnants in 37% and sac remnants in 9% 2.
• Long-term stability is maintained: At mean follow-up of 24.8 months, 93.1% of coiled aneurysms showed stable or improved occlusion 2.

Patient Selection Criteria

The decision to treat multiple aneurysms in one session should consider:

• Patient tolerance factors: Procedure duration, contrast volume exposure, and ability to maintain anticoagulation throughout the case 2.
• Aneurysm characteristics: Size, location, neck width, and dome-to-neck ratio all affect technical difficulty 4.
• Clinical presentation: Patients with ruptured aneurysms (SAH) had lower rates of favorable outcomes (77.1%) compared to unruptured cases (97.7%), though this reflects the severity of hemorrhage rather than the multi-aneurysm approach 2.

Advantages of Single-Session Treatment

Beyond safety, same-session treatment offers practical benefits:

• Cost savings: Treating multiple aneurysms in one procedure reduces hospital costs, anesthesia exposure, and recovery time 1.
• Single anesthesia exposure: Particularly important for elderly patients or those with comorbidities 2.
• Comprehensive treatment: In 78.4% of cases, all detected aneurysms were successfully treated with coiling alone in a single session 2.

Common Pitfalls to Avoid

Critical errors that compromise outcomes include:

• Treating proximal before distal aneurysms: This forces catheter manipulation through freshly coiled aneurysms, risking coil displacement 1.
• Inadequate anticoagulation management: Thromboembolic complications are the most common adverse event during endovascular coiling and require meticulous anticoagulation throughout the procedure 5.
• Ignoring contrast load limits: Extended procedures treating multiple aneurysms increase contrast-induced nephropathy risk, particularly in patients with baseline renal dysfunction 2.
• Attempting treatment beyond operator expertise: Complex aneurysm anatomy (wide neck, small size <3mm, or unfavorable dome-to-neck ratio) may require staged procedures or surgical clipping 6, 4.

When to Stage Procedures

Consider treating aneurysms in separate sessions when:

• Contrast volume approaches nephrotoxic thresholds (typically >300-350 mL depending on renal function) 2.
• Procedure time exceeds 3-4 hours, increasing risk of positioning complications and patient intolerance 2.
• Complex anatomy requires stent-assisted coiling of multiple aneurysms, necessitating dual antiplatelet therapy and increasing hemorrhagic risk 7, 5.
• Patient develops intraprocedural complications such as aneurysm perforation or thromboembolic events requiring immediate management 5.