Feasibility of Using Bluetooth Low Energy Beacon Sensors to Detect Magnifier Usage by Low Vision Patients

Abstract

Significance: We demonstrated proof of concept for the potential for Bluetooth low energy beacons to reliably collect data to serve as an indicator that low vision patients are using handheld magnifiers for reading, which might be used in the future to prevent the abandonment of magnification or other assistive devices.

Purpose: Bluetooth low energy beacons are an emerging novel technology involving tiny sensors that collect real-time, continuous, objective data, which might help to ascertain the abandonment of low vision devices in a timely manner, thus prompting a follow-up evaluation to attempt to resolve issues. We evaluated whether Bluetooth beacon data could indicate when low vision patients used handheld optical magnifiers for reading.

Methods: We recorded temperature and/or relative humidity data from Estimote sticker and BlueMaestro Tempo Disc beacons attached to handles of optical magnifiers used for reading by low vision patients in clinic (n = 16) and at home (n = 3).

Results: In the clinic, patients whose hand/fingers made direct versus indirect contact with Estimote beacons had greater temperature increases on average from baseline after 30 seconds (0.73°C vs. 0.28°C), 60 seconds (1.04°C vs. 0.40°C), 90 seconds (1.39°C vs. 0.60°C), 105 to 120 seconds (1.59°C vs. 0.62°C), and 135 to 150 seconds (2.07°C vs. 0.97°C). During magnifier usage at home, BlueMaestro beacons measured rapidly increased temperature (5.6°C per minute on average; range 2.7 to 7.3°C) and relative humidity (19.4% per minute on average; range 8.7 to 34%). Humidity tended to reach its maximum increase and return back to baseline significantly more quickly than temperature (P = .007). All increases during magnifier usage were much greater than the maximum room fluctuations without use (clinic, 0.2°C over 120 seconds; home, 0.6°C and 2.4% over 1 minute). The beacons were nonintrusive and acceptable by patients.

Conclusions: Estimote and BlueMaestro beacons can reliably detect temperature and/or humidity increases when held by low vision patients while reading with a magnifier.