A telemedicine instrument for remote evaluation of tremor: design and initial applications in fatigue and patients with Parkinson's Disease

Abstract

IntroductionA novel system that combines a compact mobile instrument and Internet communications is presented in this paper for remote evaluation of tremors. The system presents a high potential application in Parkinson's disease and connects to the Internet through a TCP/IP protocol. Tremor transduction is carried out by accelerometers, and the data processing, presentation and storage were obtained by a virtual instrument. The system supplies the peak frequency (fp), the amplitude (Afp) and power in this frequency (Pfp), the total power (Ptot), and the power in low (1-4 Hz) and high (4-7 Hz) frequencies (Plf and Phf, respectively).MethodsThe ability of the proposed system to detect abnormal tremors was initially demonstrated by a fatigue study in normal subjects. In close agreement with physiological fundamentals, the presence of fatigue increased fp, Afp, Pfp and Pt (p < 0.05), while the removal of fatigue reduced all the mentioned parameters (p < 0.05). The system was also evaluated in a preliminary in vivo test in parkinsonian patients. Afp, Pfp, Ptot, Plf and Phf were the most accurate parameters in the detection of the adverse effects of this disease (Se = 100%, Sp = 100%), followed by fp (Se = 100%, Sp = 80%). Tests for Internet transmission that realistically simulated clinical conditions revealed adequate acquisition and analysis of tremor signals and also revealed that the user could adequately receive medical recommendations.ConclusionsThe proposed system can be used in a wide spectrum of telemedicine scenarios, enabling the home evaluation of tremor occurrence under specific medical treatments and contributing to reduce the costs of the assistance offered to these patients.

Using a Smart Phone as a Standalone Platform for Detection and Monitoring of Pathological Tremors

“…Mobile technology is currently used to transmit or store data obtained from laboratory instruments (Barroso Junior et al, 2011). With the current study, we demonstrate that mobile phones can be used as a standalone platform to assess abnormal motor behaviors such as tremor and as a tool to perform clinical evaluations.…”

“…Patients can manually complete a diary of the evolution of their tremor over several days; however, they may have a difficult time accurately and objectively evaluating their own symptom severity and the effect of medication. Some quantitative methods were developed, such as an electromagnetic tracking device (O’Suilleabhain and Dewey, 2001), a mechanical linkage device on the fingertip (Matsumoto et al, 1999), lasers (Beuter et al, 1994), electromyography (Askari et al, 2010), wearable sensors (Chen et al, 2011), miniature gyroscopes (Salarian et al, 2007), digitizing tablets (Aly et al, 2007), a tremor pen (Papapetropoulos et al, 2010), and accelerometers (Barroso Junior et al, 2011). However, such devices are not readily available to patients or clinicians, they require technical expertise when manipulating hardware and analyzing results, and there are substantial costs associated with their purchase.…”

Development of wearable inertial sensors for measurement of hand arm tremors

“…FFT is used to analyze the frequency spectrum of the tremor as the frequency and amplitude component of tremor are of interest by the researchers. The output sampling time of 10 ms is sufficient to quantify tremors which commonly have frequency less than 30 Hz [12].…”

“…In order to create better assessment of oscillation data, the positions and orientations measured were mathematically treated, for instance converting raw linear and angular magnitude to rms, energy function, log and sum of magnitude within a period [2,6,[8][9][10][11][12]. These data can then be analyzed in time series analysis, spectral analysis or joint time and frequency analysis.…”

Mobile health and Parkinson: what is the future?

“…Barroso et al2 developed a pilot technological system that incorporated mobile phone along with Internet technologies to assess the frequency of tremors among PD patients within the comfort of their homes.…”