Fantastic case of essenitally single vertebral artery supply of the brain, in setting of multiple congenital variations, including the supremely rare hyostapedial variant of both IMAX and MMA / AMA supply by the ICA
Patient presents with this basilar aneurysm: Confusing, huh…
Right CCA — congenintal absence of ICA— accessory meningeal reconstitution of the anterior cerebral artery territory via the supremely rare ventral ophthalmic artery
Ventral ophthalmic — black arrows. Right bottom image — absence of right carotid canal
Right side — both the IMAX and MMA are supplied by the ICA — the extremely early embryonic hyostapedial stage. The accessory meningeal retrogradely supplies the ophthalmic artery proper, contributing to reconstitution of the intradural left ICA. The cavernous segment of the ICA is congenitally absent.
ICA — white arrows. Hyostapedial / IMAX — black arrows
Diagram
Most of the brain is supplied by the left vert, via basilar/PCOMs
Basilar Flow-related aneurysm pipeline device embolization. A single somewhat oversized device is used. The proximal portion does not open well. Removing it and putting in another one is certainly a good option.
Here the device is balloon angioplastied after deployment and does well
All done radially — 7F RIST, 5EX Sofia, Phenom 27
MP4 CTA