Objective: To assess the neuroimaging features of Parkinson's Disease and dystonia by transcranial sonography (TCS).
Methods: 63 Parkinson's Disease patients, 32 dystonia patients and 81 controls underwent TCS in blind manner. The echo of the substantia nigra (SN) was classified into I-V as half quantitative data. The echo of SN≥III was considered to be positively enhanced, the hyperechogenicity were measured and the hyper-substantia nigra/midbrain (S/M) were calculated. The echo of the lentiform nucleus (LN) was classified into I-III as half quantitative data. The echo of LN≥II was considered to be positively increased and were measured.
Result: Semi-quantitative analysis: the ratio of the patients with SN≥III was greater in Parkinson's Disease patients (60.32%, 38/63) than in dystonia patients (12.50%, 4/32) and normal controls (11.11%, 8/72, χ2=19.67, 36.22, P<0.01, respectively), the ratio of the patients with LN≥II was greater in dystonia patients (65.62%, 21/32) than in Parkinson's Disease patients (20.63%, 13/63) and in controls (8.33%, 6/72, χ2=18.69, 37.83, P<0.01, respectively). Quantitative analysis:the median and quartile (M/Q) of the SN hyperechogenieity area in Parkinson's Disease patients [0.73 (0.53) cm2] was greater than in dystonia patients [0.56 (0.53) cm2] and in controls [0.44 (0.19) cm2, H=10.05, P=0.007], the S/M in Parkinson's Disease patients was greater [15.7% (11.5%)] than in dystonia patients [(13.8% (14.2%)] and in controls [8.9% (2.9%), H=6.96, P=0.031]. The M/Q of LN hyperechogenieity area in dystonia patients was greater [0.50 (0.33) cm2] than in Parkinson's Disease patients [0.45 (0.22) cm2] and in controls [0.35 (0.17) cm2, H=10.87, P=0.004].
Conclusion: TCS might find the specific hyperechogenicity of SN in Parkinson's Disease patients (60.32%) and hyperechogenicity of LN in dystonia patients (65.63%), which could provide useful informations to distinguish Parkinson's Disease from dystonia.