Differential diagnosis of disorders manifesting with tremor on the basis of their clinical and neurophysiological characteristics

Abstract

To search for additional methods of differential diagnosis ofessential tremor (ET) and early-stage Parkinsons disease(PD), a clinical, psychometric, tremorometric, stabilometricand electrooculografic study was carried out in PD, ET andage-matched controls. Patients with ET had bilateral distributionof predominantly postural-kinetic tremor with slightprevalence in one hand, and limb tremor often combined withhead tremor. PD was characterized by asymmetric debut ofclinical manifestations, as well as by rest and postural tremorwith slight hypokinesia and rigidity. The frequency of rest andpostural tremor was significantly higher than in the PD group.Stabilometry revealed improvement of postural stability inTarget-test in patients with PD. In the dynamic Evolventatestpatients with PD showed smaller statokinetic curve lengthand lower center-of-motion velocity compared to healthy subjects.No stabilometric changes were found in ET patients. Incontrast to ET, patients with PD were characterized by significantincrease in latencies of saccadic eye movements and fractionof multi-step saccades; eye movements lateralization wasrevealed on stage I of PD. Discussed is significance of theobtained data for clinical practice.

Keywords

• parkinson’s disease
• essential tremor
• tremorometry
• stabilometry
• saccades