Parkinson’s disease results in motor impairment that deteriorates patients’ quality of life. One of the symptoms negatively interfering with daily activities is kinetic tremor which should be measured to monitor the outcome of therapy. A new instrumented method of quantification of the kinetic tremor is proposed, based on the analysis of circles drawn on a digitizing tablet by a patient. The aim of this approach is to obtain a tremor scoring equivalent to that performed by trained clinicians. Models are trained with the least absolute shrinkage and selection operator (LASSO) method to predict the tremor scores on the basis of the parameters computed from the patients’ drawings. Signal parametrization is derived from both expert knowledge and the response of an artificial neural network to the raw data, thus the approach was named multimodal. The fitted models are eventually combined into model ensembles that provide aggregated scores of the kinetic tremor captured in the drawings. The method was verified with a set of clinical data acquired from 64 Parkinson’s disease patients. Automated and objective quantification of the kinetic tremor with the presented approach yielded promising results, as the Pearson’s correlations between the visual ratings of tremor and the model predictions ranged from 0.839 to 0.890 in the best-performing models.
1 January 2015 in Biocybernetics and Biomedical Engineering
Alcoholism is one of the most widely occurring addiction in the world. In this paper, we proposed the method of addiction detection based on polysomnography. We have got the sleep records which were described by numerical parameters calculated from standard processed records of polysomnography signals. The database used in the experiments consisted of 172 examinations: 50% of healthy and alcohol-addicted patients, and 50% males and females, with normal-like age distribution. For the diagnosis, we have used the decision system built on an artificial neural network. In our investigations, we have optimised the input set of parameters and the network structure. To verify the correctness of the diagnosis we have used the “leave one out” validation method. Finally, we have obtained over 97% correctness of alcohol addiction diagnoses for different, optimised sets of data for men and women. we got the 8 parameters described men and 11 for women where only 5 has been common. What must be underlined such a positive result was obtained by dividing the data base. For the whole base, we have got only about 89% correct diagnoses.
Above discussed aspects, considerations and technical possibilities, as well as methodological requirements, guidelines and clinical applications of proton spectroscopy strengthens our belief in the power of this method used in neurooncological diagnosis.
1 January 2016 in Parkinsonism & Related Disorders