Susceptibility-weighted Imaging In Detecting Brain Iron Accumulation Of Parkinson's Disease At 3.0 Tesla MRI

Purpose To evaluate the clinical value of susceptibility-weighted imaging (SWI) in the measurement of brain iron in Parkinson's disease at 3.0 Tesla MRI.Materials and Methods A total of 30 PD which were clinical diagnosis and 19 age-matched control subjects were examed by head conventional and SWI sequences . PD was classified by I-IV stage(Hoehn-Yahr) and two groups according to disease duration(≤5year,>5year). The signals of conventional MRI and SWI were observed. The phase images were high-pass-filtered and processed region by region with hand-drawn areas. The regions evaluated included putamen (PUT), globus pallidus (GP), caudate nucleus (CN), substantia nigra (SN), and red nucleus (RN). The phases were measured and analyzed by t-test with the control group,and also compared based on Hoehn-Yahr stages and PD duration. The areas of SN were also measured and analyzed.Results The signal of iron deposition was low in corrected phase imaging ,magnetic imaging and SWI imaging. There were significant statistically defferences of the phase value of substantia nigra(P=0.014<0.05) and globus pallidus(p=0.006<0.05), consistent with higher iron levels in the SN and GP in PD group relative to the controls.While of PUT,CN and RN had no significant statistically differences.Only in the SN,phase values were lower in cases with Hoehn-Yahr III-IV than those cases with I-II(p=0.000<0.05),demonstrated that the SN had higher iron level .Phases were not significant different in the RN,PUT,CN and GP.Phase changes in 30 PD patients of the two group did not correlated with disease duration in all the SN,RN,PUT,CN and GP(p>0.05). There were significant statistically defferences of the iron accumulation areas of SN(P=0.000<0.05),that is the PD group had smaller areas compared to the controls.Using the final clinical diagnosis as gold standard and -0.1109 as threshold value, the sensitivity of diagnosis of PD was 60.00%(18/30), the specificity was57.89%(11/19),the accuracy was 59.18%(29/49).Conclusions SWI provided a non-invasive sensitive quantitatively methods for study the process of pathological changes of iron deposition in PD and it can help us to recognize and detect PD and sub-clinical PD.