Article Figures & Data
Figures
- Fig 1.
The eye-of-the tiger sign on T2WI and iron topography on SWI at 3T MR imaging (NL, P11, P12, P13) and 7T MR imaging (P15). On T2WI, the round hyperintense center is reduced in size with extension of the surrounding hypointensity. A noticeable difference in signal hypointensity between the medial and lateral segments of the globus pallidus tends to be obscured with increasing age (arrows). The reduction of signal intensity in both the subthalamic nucleus and substantia nigra (P15, arrow) tends to be proportional to that of the GP. The fiber connections of the medial GP with the SN and STN are dramatically visualized (P13, open arrow). NL indicates healthy control; P11/P12/P13/P15, the number of patients in the On-line Table; y., years of age.
- Fig 2.
Early MR imaging changes in the globus pallidus. The linear T2-hyperintensity that streaks along the medial border of the GP is the earliest T2 change (A, arrowhead). The round center in the anteromedial aspect is first observed at 3 years of age (B, left). Subtle hypointensity is also detected on the susceptibility-weighted image (B, right). In patients with serial MRIs (C and D), iron-related hypointensity becomes definitely evident by 4 years of age with the appearance of an isolated T2-hyperintense center (C). The surrounding areas decrease in signal intensity with age (D). P8 and P9 indicate the number of patients in the On-line Table; m., months of age; y., years of age.
- Fig 3.
Atypical features of the eye-of-the-tiger sign. The hyperintense area in the anteromedial globus pallidus has totally disappeared at the anterior commissural level (A, left) but is partly visible at just above that level (A, right, arrow). The dark streaks extend into the hyperintense centers (B, left, arrow). The remaining component of hypointensity is observed as hyperintense stripes (B, right, short arrow). T2-hyperintensity extends into the genu of the internal capsule (B, right, long arrow). The hyperintense areas are unusually located in the whole medial GP (C) and posterior GP (D). The hyperintense center is obscured in a patient with GP calcification (E). y. indicates years of age.
- Fig 4.
Graph shows the age distribution of the eye-of-the tiger sign classified into 3 categoric patterns. “Hyper-center” indicates T2-hyperintense center of the GP; “hypo-surrounding,” the surrounding area with T2-hypointensity; atypical, atypical features.
