Proton magnetic resonance spectroscopy in steele‐richardson‐olszewski syndrome

Proton magnetic resonance spectroscopy, localized to the lentiform nucleus, was carried out in nine patients with a clinical diagnosis of Steele‐Richardson‐Olszewski syndrome (SRO) and in eight healthy age‐matched controls. Three of the nine SRO patients had a so‐called “eye of the tiger sign” with high signal in the globus pallidus surrounded by a ring of low signal on T2 weighted magnetic resonance imaging previously only reported in Hallervorden‐Spatz disease. One of these patients had pathologically proven SRO at postmortem. The SRO group showed a significant reduction in the median concentration from N ‐acetyl groups (median, 6.87 m M ; range, 4.92–10.59 m M ; p < 0.015) compared with the control group (median, 9.85 m M ; range, 9.26–11.0 m M ). The N ‐acetylaspartate concentration was significantly reduced in seven of the nine patients studied. The reduction of the N ‐acetylaspartate‐creatine ratio from the lentiform nucleus in the SRO group may reflect neuronal loss, occurring predominantly in the globus pallidus. Proton magnetic resonance spectroscopy may be a useful, noninvasive technique to help differentiate the various parkinsonian syndromes.