COMMENT. In the differential diagnosis of dystonia, a CT scan showing calcification in the basal ganglia lead to tests for hypoparathyroidism whereas an MRI may be helpful in the diagnosis of Hallervorden-Spatz disease. Dystonia and striking MRI abnormalities in the globus pallidus (“eye-of-the-tiger” sign) are described in 2 patients with Hallervorden-spatz syndrome [2]. One patient developed arching of the body backward and a diagnosis of dystonia at 14 years. She slowly deteriorated and at age 20 had progressive difficulty with mouth closure and at 32 years, frequent falling. CT scan of the head was normal whereas the MRI T2-weighted images showed a low-signal area surrounding a relatively circumscribed region of high signal in the globus pallidus. The 'eye-of-the-tiger' sign is an appropriate name for this abnormality. The second patient, a 20-year-old woman, had a 1-year history of progressive difficulty with night vision and repeated forceful eye closure aggravated by sudden noise and attempted eye opening. The neurological findings were frequent blepharospasm, repetitive slow tongue protrusion, and tapetoretinal degeneration. Slow deterioration occurred over the next 2 years and reexamination showed facial grimacing, severe blepharospasm, tongue protrusion, resting tremor of hands, tongue, and jaw, and cogwheel rigidity of arms. CT scan was normal and the MRI showed the “eye-of-tiger” sign in the globus pallidus.