Background & Aims
Peripheral neuropathies often have an insidious onset meaning that irreversible damage occurs before preventative strategies are deployed – commonly resulting in chronic pain. Quantitative Sensory Testing (QST) is employed as a research method to assess sensory nerve function, and thus may make early detection of neuropathy feasible. However, QST currently is lab/clinic based, uses complex equipment and requires a skilled practitioner to conduct the standardised tests. Although simplified bedside QST protocols exist these still require a skilled practitioner to conduct and take time. Regular longitudinal QST testing is important for early neuropathy detection because within subject data granularity is required to identify the early stages of neuropathy.
SenseCheQ aims to create an easy-to-use QST kit, to test A- and C- fibre sensory nerve function (warm, cold and vibration detection thresholds) with a simple user interface suitable for home use by patients.
Methods
We developed SenseCheQ through iterative engineering with feedback validation from lab-based and healthy volunteer testing, with PPIE embedded in the team. To keep build costs low, SenseCheQ is constructed using off-the-shelf electronic componentry. Warming and cooling is provided via well-established PID-driven Peltier technology, whilst vibration stimulation is provided via a high-fidelity haptic device. The standard SenseCheQ home test protocol has been optimised to take less than 15 minutes to complete. The interface consists of two buttons for start and stop of each test and simple instruction set on a display screen contained within a single enclosure, whilst the lab and clinical version has the option of running custom test protocols.
Results
SenseCheQ is more than capable of reliably delivering 0.5°C.s-1 ramp rates, to cool (Meanrate = 0.49° [0.48-0.50]) or heat (0.52° [0.51 -0.53]) by up to 10°C from a stabilised clamped baseline skin temperature (target 32°C vs actual = 31.97° [31.95-31.98]). Thermal detection thresholds from SenseCheQ are comparable to those collected using commercial QST devices.
SenseCheQ is better at defining vibration detection thresholds than the current clinical gold standard Rydel-Seiffer calibrated tuning fork, due to the combination of ascending vibrational ramps (reducing accommodation) and better resolution in the low-amplitude range. The tuning fork suffers from a floor effect, whereby considerable sensory loss must occur before a change in the detection threshold is identifiable. In contrast SenseCheQ can be driven at amplitudes below the detection limit of healthy participants.
Conclusions
We have developed a simple-to-use QST kit which allows patients to self-test their nerve function at home, on a much more granular basis than is currently possible. Wider deployment of QST could be advantageous for patients at risk of developing peripheral neuropathy. SenseCheQ has also been designed with academic and clinical flexibility in mind and provides a low-cost option for QST.
References
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Presenting Author
Johannes Gausden
Poster Authors
Johannes Gausden
PhD
Newcastle University
Lead Author
Marin Dujmovic
School of Physiology, Pharmacology, and Neuroscience, University of Bristol
Lead Author
Bethany Groves
MSc
University of Bristol
Lead Author
Tom Bennett
MSc
University of Bristol
Lead Author
Lesley Colvin
University of Dundee
Lead Author
Roger Whittaker
PhD
Newcastle University
Lead Author
James Dunham
University of Bristol, United Kingdom.
Lead Author
Anthony O'Neill
BSc
Lead Author
Topics
- Assessment and Diagnosis