Fig 3.

Assessment of the horizontal part of the C6 segment of the ICA, by using a transtemporal axial approach. Top: Time-of-flight MRA, axial source image, rotated 90° to correspond with the sonographic image. Horizontal part of the C6 segment (arrows). Bottom: TCCS, transtemporal approach, axial lower pontine plane. Right: Color-mode image demonstrates the horizontal part of the C6 segment. Left: Corresponding Doppler spectrum. Reprinted from Valdueza et al⁸ with permission from Thieme Medical Publishers, Stuttgart, Germany.