Which acoustic window is used as the primary access to intracranial vessels in transcranial Doppler imaging?

• A. Transorbital
• B. Transtemporal
• C. Transforamenal/Suboccipital
• D. Submandibular

Answer: (B)

The main idea is that the transtemporal window provides the clearest, most reliable path to the intracranial vessels for Doppler assessment. Located over the temple where the temporal bone is relatively thin, it offers direct access to the Circle of Willis and its major branches. From this window you can commonly insonate the middle cerebral arteries and also sample the anterior and posterior cerebral arteries, with the terminal internal carotid visible in many cases. Because the signal tends to be strong and consistent and you can evaluate multiple vessels from a single site, this window is the primary access used in routine transcranial Doppler exams. Other windows exist to reach vessels that aren’t easily seen from the temple—such as transorbital for the carotid siphon, transforamenal/suboccipital for the vertebrobasilar system, and submandibular for additional segments—but they’re used when the transtemporal window is inadequate or when specific vessels are targeted.