Figure 4
From: Diagnosis of extracranial carotid stenosis by MRA of the brain
Demonstration of the three imaging parameters in three different patients with different stenosis percentages of the internal carotid arteries (ICAs). (A) Nearly total occlusion of the right ICA. Right grade 3 (arrowhead in A2 for no visible opacification of the ophthalmic artery) and left grade 2 (arrow in A2 for distal end of the ophthalmic artery opacification) of the ophthalmic artery opacification were depicted. Decreased diameter and signal intensities of the right petrous ICA (arrow in A3) compared to the contralateral side were noted. (B) Right ICA with 77.2% stenosis. Right grade 2 (arrowhead in B2 for distal end of the ophthalmic artery opacification) and left grade 1 (arrow in B3 for distal end of the ophthalmic artery opacification; the dotted line indicated the level of the posterior border of the globe) ophthalmic opacification were noted. Slightly decreased signal intensity without significant diameter discrepancy of the right petrous ICA (arrow in B4) compared to the contralateral side were demonstrated. (C) Left ICA with 59.4% stenosis. Bilateral grade 2 ophthalmic opacification with a tiny ophthalmic artery budding from the right ICA (arrow in C2). No significant discrepancy of signal intensities or diameter are depicted between bilateral petrous ICAs (C3).
