Assessment of cerebral iron content in patients with Parkinson's disease by the susceptibility-weighted MRI.

OBJECTIVE The overall goal of this study was to evaluate the usability of the susceptibility weighted imaging (SWI) in (1) assessment of iron deposition to enhance our ability to detect PD in the early phase and (2) in estimation of the degree of PD. PATIENTS AND METHODS SWI scans were carried out in 54 patients with PD (18 patients with the Hoehn-Yahr scale < 1.5 and 36 patients with the Hoehn-Yahr stage > 1.5) and 40 control individuals. The phase values of the substantia nigra, red nucleus, caudate nucleus, putamen, and globus pallidus were measured on the corrected phase image. RESULTS Compared with control individuals, patients with both the early and intermediate/ advanced stages of PD had significantly different phase values in the substantia nigra, red nucleus, caudate nucleus, putamen, and globus pallidus (all p < 0.05). The phase values of the substantia nigra and globus pallidus inversely correlated with the Hoehn-Yahr scale (respectively, r = -0.845, p < 0.05, and r = -0.868, p < 0.05). Weaker correlations were found between the phase values of red nucleus, caudate nucleus, putamen, and Hoehn-Yahr scale (red nucleus r = -0.543, caudate nucleus r = -0.620, p < 0.05, putamen r = -0.537). CONCLUSIONS A semi-quantitative assessment of the iron content of the substantia nigra and globus pallidus with the help of SWI may be useful for early diagnosis of PD and evaluation of the degree of this disease.