Republished: Competitive flow diversion of multiple P1 aneurysms: proposed classification

Area of Science:

• Neurosurgery
• Endovascular Therapy
• Cerebrovascular Disease

Background:

• Subarachnoid hemorrhage (SAH) poses significant risks, often caused by intracranial aneurysms.
• Complex aneurysms at the circle of Willis, particularly involving the posterior communicating artery (Pcomm)-P1 complex, present treatment challenges.

Observation:

• A patient presented with SAH and three aneurysms: one large Pcomm aneurysm and two smaller posterior cerebral artery (PCA) P1 segment aneurysms.
• Initial treatment attempts included traditional endovascular coiling for the large aneurysm and failed conventional flow diversion for the PCA P1 aneurysms.

Findings:

• The Pcomm aneurysm was successfully treated with endovascular coiling.
• A novel competitive flow diversion technique, applied distal to the PCA-P1 segment from Pcomm to P2, successfully obliterated the two PCA P1 aneurysms.
• Over 12 months, this competitive flow diversion strategy redirected flow, reduced PCA P1 segment size, and achieved aneurysm obliteration.

Implications:

• Competitive flow diversion is a viable alternative for complex intracranial aneurysms when conventional treatments are not feasible.
• This case introduces a novel classification for competitive flow diversion, potentially guiding future treatment strategies for cerebrovascular neurosurgery.