Relations of clinical symptoms with dopamine transporter imaging in drug-naïve Parkinson's disease

Striatal Dopaminergic Depletion Pattern Reflects Pathological Brain Perfusion Changes in Lewy Body Diseases

PURPOSE

In Lewy body diseases (LBD), various symptoms occur depending on the distribution of Lewy body in the brain, and the findings of brain perfusion and dopamine transporter single-photon emission computed tomography (DAT-SPECT) also change accordingly. We aimed to evaluate the correlation between brain perfusion SPECT and quantitative indices calculated from DAT-SPECT in patients with LBD.

PROCEDURES

We retrospectively enrolled 35 patients with LBD who underwent brain perfusion SPECT with N-isopropyl-p-[¹²³I] iodoamphetamine and DAT-SPECT with ¹²³I-ioflupane. Mini-mental state examination (MMSE) data were also collected from 19 patients. Quantitative indices (specific binding ratio [SBR], putamen-to-caudate ratio [PCR], and caudate-to-putamen ratio [CPR]) were calculated using DAT-SPECT. These data were analysed by the statistical parametric mapping procedure.

RESULTS

In patients with LBD, decreased PCR index correlated with hypoperfusion in the brainstem (medulla oblongata and midbrain) (uncorrected p < 0.001, k > 100), while decreased CPR index correlated with hypoperfusion in the right temporoparietal cortex (family-wise error corrected p < 0.05), right precuneus (uncorrected p < 0.001, k > 100), and bilateral temporal cortex (uncorrected p < 0.001, k > 100). However, there was no significant correlation between decreased SBR index and brain perfusion. Additionally, the MMSE score was correlated with hypoperfusion in the left temporoparietal cortex (uncorrected p < 0.001).

CONCLUSIONS

This study suggests that regional changes in striatal ¹²³I-ioflupane accumulation on DAT-SPECT are related to brain perfusion changes in patients with LBD.

Characteristics of wearing-off and motor symptoms improved by safinamide adjunct therapy in patients with Parkinson's disease: A post hoc analysis of a Japanese phase 2/3 study

INTRODUCTION

Patients with Parkinson's disease (PD) experience various motor and non-motor symptoms. We conducted a post hoc analysis of a Japanese phase 2/3 study of safinamide (50 or 100 mg/day) in patients with Parkinson's disease and wearing-off to evaluate response according to background factors. Safinamide efficacy against major motor symptoms was also assessed.

METHODS

Multiple regression analyses in safinamide-treated patients (50 or 100 mg/day) assessed changes in daily ON-time without troublesome dyskinesia (hereafter referred to as ON-time) according to baseline clinical variables. Subgroup analyses by baseline Unified Parkinson's Disease Rating Scale (UPDRS) part III score were also conducted. We evaluated cardinal motor symptoms using the UPDRS.

RESULTS

In the multiple regression analysis, changes in ON-time were related to baseline non-motor symptoms (UPDRS part I score) and ON-time in the 50-mg group, but no relationships with non-motor symptoms were observed in the 100-mg group. Additionally, in the subgroup analysis of patients with more severe motor symptoms (UPDRS part III score > 20), a significant improvement in ON-time was observed only with 100 mg/day (p = 0.01). At both doses, safinamide significantly improved cardinal motor symptom scores (bradykinesia, rigidity, tremor, axial symptoms, and gait disturbances).

CONCLUSIONS

The observed response profile to the 50-mg/day dose may be related to baseline non-motor symptoms, but this was not true for the 100-mg/day dose. Both safinamide doses improved major motor symptoms in levodopa-treated patients with PD.

Measurement of the facial nerve thickness and its correlation with freezing phenomenon and hypomimia in Parkinson's disease

OBJECTIVE

Hypomimia is one of the diagnostic features in Parkinson's disease, and freezing blocks may also occur with the degenerative process. We investigated that the thickness of the cranial facial nerve that innervates facial expressions, and the relationship between bradymimia and freezing phenomena in these patients.

METHODS

We included 70 patients and healthy participants in this cross-sectional study. Clinical characteristics, modified Hoehn and Yahr (mHY) stages, Unified Parkinson's Disease Rating Scale (UPDRS) scores and Freezing of Gait Questionnaire (FOG-Q) scores of Parkinson's patients were recorded. FOG-Q was scored between 1 and 4 points. The thickness of the facial nerve and its neighborhoods of numerically equal groups were measured radiologically in the internal acoustic channel (IAC) with magnetic resonance imaging of temporal lobe. Right and left facial nerve thicknesses were compared.

RESULTS

The right facial nerve thicknesses of the patient and control groups were measured as 0.97 ± 0.12 mm and 1.20 ± 0.10 mm at the proximal level and 0.71 (0.69-0.81) mm and 1.21 (1.13-1.24) mm at the distal level, respectively (P < 0.001). Notably, the facial nerve was more atrophied on the right than on the left (P < 0.001). Facial nerve to IAC ratio (%) was significantly lower and cerebrospinal fluid thickness distance (%) measurement was significantly higher (P < 0.001). Also, the FOG-Q and facial nerve to IAC ratio were negatively correlated (P = 0.049, rho = -0.335).

CONCLUSIONS

Our study provides new information about the facial nerve and its neighborhoods and clinical relationships in individuals with PD. In studies investigating hypomimia and FOG in Parkinson's, neuroimaging of the facial nerve can also be used. These results need to be proven with more comprehensive studies.