China
Africa
Explore chapters and articles related to this topic
Measurement of Hand Tremor Forces with Strain-Gauge Force Transducer
Published in Mesut Sahin, Howard Fidel, Raquel Perez-Castillejos, Instrumentation Handbook for Biomedical Engineers, 2020
Mesut Sahin, Howard Fidel, Raquel Perez-Castillejos
Tremors can be classified into two main categories, resting tremor and action tremor. A resting tremor occurs when the muscle is relaxed, such as when the hands are resting on the lap. This type of tremor is often seen in people with Parkinson’s disease and is called a “pillrolling” tremor because the circular finger and hand movements resemble rolling of small objects or pills in the hand. The second main category is the action tremor. This occurs with the voluntary movement of a muscle. There are several sub classifications of action tremor, for example, postural, kinetic, intention, task-specific and isometric tremor. The intention tremor is produced with purposeful movement toward a target, such as lifting a finger to touch the nose or moving a leg to kick a ball.
Deep brain stimulation programming strategies: segmented leads, independent current sources, and future technology
Published in Expert Review of Medical Devices, 2021
Bhavana Patel, Shannon Chiu, Joshua K. Wong, Addie Patterson, Wissam Deeb, Matthew Burns, Pamela Zeilman, Aparna Wagle-Shukla, Leonardo Almeida, Michael S. Okun, Adolfo Ramirez-Zamora
Several studies have analyzed LFP data from GPi and thalamic DBS collected from Tourette syndrome (TS) subjects. These studies have proposed potential electrophysiologic biomarkers [133–136]. The studies have identified low-frequency oscillatory activity (1–10 Hz) prior to and during motor tics. Algorithms for aDBS in TS have been proposed and studies assessing these algorithms are currently ongoing. A variation of aDBS using external data has also been applied for intention tremor in ET patients. Basu et al. demonstrated 100% sensitivity of tremor detection using surface EMG in both ET and PD with a 85.7% and 80.2% accuracy, respectively [137]. Yamamoto et al. examined the feasibility of an ‘on-demand’ stimulation trigger based on external EMG sensors in four ET patients [138]. In this study, four patients underwent surface EMG analysis, and the results revealed a consistent 3 Hz disabling intention tremor. A signal processor was programmed to turn on the DBS system externally when the 3 Hz power reached a trigger threshold and to turn off the DBS system when the 3 Hz power was below the threshold. The authors completely suppressed the intention tremor using this method. A similar pilot study utilizing external sensing aDBS was conducted in ten PD patients with STN-DBS [139]. Upper extremity tremor data was collected via a wearable smart watch. During a 30-minute trial, aDBS provided a mean improvement of 37% more tremor suppression than cDBS while requiring 48% less stimulation time and 76% lower stimulation voltage. Cabrera et al. highlight the potential use of electrochemical sensing to detect changes in neurotransmitters across diseases as a method to serve as a biomarker in a closed-loop DBS system [140]. Additional studies are still needed to determine the use, safety, and feasibility of electrochemical sensing.