(1) Objective: To evaluate the usefulness of a three-dimensional motion-analysis system (AKIRA^®) as a quantitative measure of motor symptoms in patients with Parkinson’s disease (PD). (2) Method: This study included 48 patients with PD. We measured their motion during 2 m of walking using AKIRA^®, we calculated the tilt angles of the neck and trunk, ankle height, and gait speed, then we compared these parameters with the MDS-UPDRS and the Hoehn and Yahr scale. Furthermore, we measured these AKIRA indicators before and after 1 year of observation. (3) Results: The forward tilt angle of the neck showed a strong correlation with the scores on parts II, III, and the total MDS-UPDRS, and the tilt angle of the trunk showed a moderate correlation with those measures. The lateral tilt angle of the trunk showed a moderate correlation with a freezing of the gait and a postural instability. Regarding changes over the course of 1 year (n = 34), the total scores on part III of the MDS-UPDRS and the forward tilt angle of the neck improved, while the lateral tilt angle of the trunk worsened. (4) Conclusion: Taken together, the forward and lateral tilt angles of the neck and trunk as measured by AKIRA^® can be a candidate for quantitative severity index in patients with PD.

The utility of transcranial sonography (TCS) remains unclarified for the auxiliary diagnosis of Parkinson’s disease (PD). We investigated iodine-123 metaiodobenzylguanidine (MIBG) and TCS during the examination and diagnosis of high-signal-intensity substantia nigra lesion (HSI-SNL) incidence in PD patients previously diagnosed with dopamine transporter scintigraphy (DAT). The subjects were 67 patients with definitively diagnosed PD after DAT evaluation. Patients with midbrain substantia nigra visible during TCS who previously underwent MIBG were analyzed. The SN+ group comprised patients with extensive pathological HSI-SNL of Okawa class III/IV observed during TCS. The MIBG+ group comprised patients with a heart-to-mediastinum ratio of ≤2.2 during MIBG. TCS was performed to divide patients into the SN+ and SN− groups, and patient characteristics and MIBG findings were compared between the groups. PD was definitively diagnosed in 67 patients, among whom midbrain was visualized during TCS in 43 (64.1%) patients and pathological HSI-SNL was observed in 24 (35.8%). The MIBG findings were normal in six patients (27.3%) with HSI-SNL, and abnormal in seven (63.6%) without HSI-SNL. No significant differences were noted by Okawa classification in clinical characteristics based on the presence or absence of HSI-SNL. Multiple patients with normal findings during MIBG may have HSI-SNL. Thus, confirmatory imaging of HSI-SNL with TCS may be useful for diagnosis.