Eye of the tiger anomaly of globus pallidus

What it means

The presence, on T2-weighted magnetic resonance imaging, of markedly low signal intensity of the globus pallidus that surrounds a central region of high signal intensity in the anteromedial globus pallidus, producing an eye-of-the-tiger appearance. The sign is thought to represent iron accumulation in the globus pallidus.

This sign is observed upon magnetic resonance tomography (MRI). It can be seen in several diseases including Hallervorden-Spatz syndrome, where the pathophysiology has been hypothesized to be related to iron deposition in the globus pallidus (associated with low signal intensity on T2-weighted images) accompanied by other pathological processes such as gliosis and water accumulation that are responsible for the high signal intensity at the central globus pallidus.

Rare diseases that can present with this7

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category