Exploring the Complex Phenotypes of Impaired Finger Dexterity in Mild-to-moderate Stage Parkinson's Disease: A Time-Series Analysis

BACKGROUND

Impaired dexterity is an early motor symptom in Parkinson's disease (PD) that significantly impacts the daily activity of patients; however, what constitutes complex dexterous movements remains controversial.

OBJECTIVE

To explore the characteristics of finger dexterity in mild-to-moderate stage PD.

METHODS

We quantitatively assessed finger dexterity in 48 mild-to-moderate stage PD patients and 49 age-matched controls using a simple alternating two-finger typing test for 15 seconds. Time-series analyses of various kinematic parameters with machine learning were compared between sides and groups.

RESULTS

Both the more and less affected hands of patients with PD had significantly lower typing frequency and slower typing velocity than the non-dominant and the dominant hands of controls (p = 0.019, p = 0.016, p < 0.001, p < 0.001). The slope of the typing velocity decreased with time, indicating a sequence effect in the PD group. A typing duration of 6 seconds was determined sufficient to discriminate PD patients from controls. Typing error, repetition, and repetition rate were significantly higher in the more affected hands of patients with PD than in the non-dominant hand of controls (p < 0.001, p = 0.03, p < 0.001). The error rate was constant, whereas the repetition rate was steep during the initiation of typing. A predictive model of the more affected hand demonstrated an accuracy of 70% in differentiating PD patients from controls.

CONCLUSION

Our study demonstrated complex components of impaired finger dexterity in mild-to-moderate stage PD, namely bradykinesia with sequence effects, error, and repetition at the initiation of movement, suggesting that multiple neural networks may be involved in dexterity deficits in PD.

Nonbacterial Thrombotic Endocarditis Related to Adenocarcinoma of the Uterine Cervix

We report a 66-year-old female patient who presented with acute onset of visual loss with relative afferent pupillary defect, hemineglect, hemihypesthesia, and apraxia. Magnetic resonance imaging of the brain demonstrated different stages of ischemic stroke in different vascular territories, suggesting cardiogenic embolism. Past history was significant for advanced-stage adenocarcinoma of the uterine cervix under chemoradiation treatment. On echocardiogram, vegetation at the aortic valve was observed. With the absence of evidence of infectious endocarditis, diagnosis of nonbacterial thrombotic endocarditis was made, and the patient was treated by long-term anticoagulant. This case is unique in terms of the adenocarcinoma cell type of cervical cancer, which is uncommon and has been rarely reported to be related to nonbacterial thrombotic endocarditis.