Authors :
Presenting Author: Lykke Blaabjerg, PhD – UNEEG medical
Esben Ahrens, Mr – T&W Engineering; Jonas Duun-Henriksen, PhD, MSc – UNEEG medical; Helle Borregaard, Mrs – T&W Engineering; Sofie Nielsen, PhD – UNEEG medical; Bjarki Djurhuus, Dr, PhD – Zealand University Hospital; Preben Homøe, Dr., PhD – Zealand University Hospital; Troels Kjaer, Dr., PhD – UNEEG medical; Martin Hemmsen, PhD, MSc – T&W Engineering
Rationale:
Minimally invasive devices for continuous monitoring of brain activity are emerging to meet the need for ultra long-term, real-world EEG recordings and provide objective data to aid in epilepsy management.
Ease of use and low interference with everyday life activities are prerequisites for data to be available as these devices need to be used daily for extended periods of time.
A clinical study was set up to collect subcutaneous EEG (sqEEG) recordings in the participants’ natural environment for 365 consecutive nights to investigate sleep in the ultra-long perspective. We report on the adherence and user perspective on the minimally invasive subcutaneous EEG recording device.
Methods:
Heathy volunteers over18 years of age received the three-electrode implant and recorded sqEEG every night for a year with the 24/7 EEG™ SubQ system (UNEEG™ medical, Allerød, Denmark).
Duration of recorded sqEEG was retrieved and adherence was calculated as the percentage of nights with at least four hours of sqEEG.
The System Usability Scale (SUS) was used for subjective assessment of usability. It consists of a 10‑item questionnaire with five response options; from "Strongly agree" to "Strongly disagree." In addition, a device-specific questionnaire was used to evaluate subject satisfaction with the 24/7 EEG™ SubQ device. This was a six-item questionnaire similarly with five response options for respondents.
Both the SUS questionnaire and subject satisfaction questionnaire were administered in the beginning of the study (six weeks after start of sqEEG recording) and at the end of the study (a year after start of sqEEG recording).
Results:
Twenty-five participants enrolled in the study and 23 participants had some sqEEG recorded. Twenty participants completed the one-year study, whereas three participants withdrew during the recording phase. Across the 23 participants with sqEEG data available, adherence ranged from 74-100%. Two-thirds recorded sqEEG more than 90% of all nights.
Twenty-one participants completed the questionnaires in the beginning of the study, and 19 of the participants completed it at the end of the study.
The average SUS score was 83.1 (±10.8) following six weeks of recording and 86.3 (±9.8) following 52 weeks of recording. System Usability Scale scores between 84.1-100 are regarded as grade A or ‘best imaginable’ score for a given device (Brooke, 2013).
Overall, the participants disagreed or strongly disagreed to the use of the 24/7 EEG™ SubQ system limiting their daily activities, school/work, or spare time. They agreed or strongly agreed to colleagues, friends, and family reacting positively towards their use of the 24/7 EEG™ SubQ system and also agreed or strongly agreed to the use of the device being a positive experience. The responds obtained at the beginning of the study were very similar to those obtained at the end.
Conclusions:
Using the 24/7 EEG™ SubQ system for nocturnal recording (i.e., for sqEEG recording during sleep) throughout a year is feasible, with high adherence and a perceived usability in the category “best imaginable." Overall, the participants did not experience any limitation in their everyday life activities and had an overall positive experience using and wearing the device.
Funding: None