Usability Characteristics Assessment Protocol Applied to eTouch Ultrasound User-defined workflow Optimization Tool

The Ultrasound (US) examination time reduction is an increasing compelling request in sonographer's everyday life. The increased number of patients and the cost reduction are two opposite forces, which can lead the sonographer to work faster without caring about scanning posture. The numerous repeated actions performed can easily lead to Work-related Musculoskeletal Disorders (WRMSD). The analysis of those problems has driven to the definition and implementation of eTouch tool: user-defined Macros appositively created, automatically and sequentially saved and performed in real time by pressing a button. The present work investigates ergonomics and usability performances of a portable US system (MyLabAlpha, Esaote S.p.A., Italy) by using eTouch as well as the classical manual interface in two clinical applications (Abdominal and Vascular). performed by a skilled sonographer on a healthy subject. is. Upper-body kinematic and muscle activation of the sonographer's left arm were recorded through an optoelectronic system (SmartDx400, BTS Spa, Italy) and a multi-channel Wireless Superficial Electromyography (SEMG, Freemg300, BTS Spa, Italy). The number of keystrokes used during the manual procedure was more than 3 times higher than the one with eTouch. This difference implied a reduction of US execution time when using eTouch in comparison with manual use of about 30%. Results of the upper-body kinematic showed that the arm was extended for less time intervals when using eTouch, whereas during the manual procedure there was a greater activation of the deltoid, responsible for the elevation of the shoulder and thus the extension of the arm. SEMG analysis showed that eTouch allowed a significant reduction of muscular activation, especially for the anterior deltoideus. Our findings showed that eTouch is recommendable for decreasing WRMSD risk.