In the transorbital approach, which vessels are assessed?

• A. ophthalmic artery and carotid siphon
• B. MCA and ACA
• C. Vertebral arteries
• D. Basilar artery

Answer: (A)

The transorbital window is used to evaluate vessels that run in or near the orbit, specifically the ophthalmic artery and the intracranial segment of the internal carotid known as the carotid siphon. The ophthalmic artery travels through the orbit from the internal carotid, and the siphon represents the curved portion of the ICA as it enters the skull base, both of which can be accessed from this orbital approach. These vessels are central to assessing anterior circulation and collateral flow, carotid disease, or dissection from this view. In contrast, the MCA and ACA are typically studied through other windows, and the vertebral and basilar arteries pertain to the posterior circulation, not optimally examined via the transorbital route.