Mobile phone thermography as an ambulatory assessment for Raynaud's
Research type
Research Study
Full title
Mobile phone thermography as an ambulatory assessment tool for Raynaud’s phenomenon
IRAS ID
294630
Contact name
Ariane Herrick
Contact email
Sponsor organisation
The University of Manchester
Duration of Study in the UK
1 years, 0 months, 1 days
Research summary
Research Summary
Raynaud's phenomenon (RP) means episodic colour changes in response to cold or emotional stress. It is important because it is common (primary idiopathic/‘benign’ RP affects around 5% of the population) and also because when RP occurs secondary to connective tissue disease (especially systemic sclerosis [SSc]) it can be very severe, progressing to irreversible tissue damage with ulceration, scarring; and rarely, gangrene and amputation.
We have shown that even primary RP often has a major impact on quality of life. Current treatments are often ineffective and/or not tolerated and the development of new treatments for RP has been hampered by the paucity of reliable outcome measures. Mobile phone thermography could provide a way forward here. Thermography measures the surface temperature of the skin. Patients with RP complain of cold, discoloured fingers. Thermographic parameters have been used as outcome measures in clinical trials of RP but usually as laboratory-based tools, for example investigating whether thermographic (temperature) responses following a standard cold challenge improve after vasodilator therapy.
In Salford/Manchester we have extensive experience of applying thermography in studies of RP, and have found (in a laboratory-based study) that mobile phone thermography compares favourably to standard thermography setting the stage for ambulatory monitoring of finger/hand temperature.The aim of this study is to explore the efficacy of mobile phone thermography to capture Raynaud's phenomenon. This will be done via a feasibility study to explore how possible it is to capture images in this way in patients with Raynaud's phenomenon.
Summary of Results
Thirteen female patients with Raynaud's phenomenon (RP) related to systemic sclerosis were recruited to the study. Patients were given a FLIR One Pro thermal camera module (FLIR, Sweden) and compatible smartphone handset and instructed on how to image their hands twice-daily, morning and evening, when their hands were not affected by RP. Patients were asked to image RP attacks, with ideally at least three images (“start”, “middle, and “end”) for each attack. They were also given a paper daily diary to record timing of daily images, details of any RP attacks, and a Raynaud's Condition Score (RCS - a validated scoring scale for RP). At the second visit patients returned the handset and completed a feasibility questionnaire.
Suitable images (of whole hands only) were manually annotated using custom software. Images were further classified as either ‘daily images’, or as part of an RP attack by matching up the image metadata with the patient-recorded information about RP attacks in the paper diaries.
Twelve patients (92%) completed the study (one lost to follow-up), returning 352 images in total (range: 4-54), of which 251 were suitable for further analysis - 176 were twice-daily images and 75 RP attack images.Feasibility questionnaire responses confirmed the general feasibility of patients recording thermal images of their hands at home (see published manuscript for details).
Mean temperatures [Standard deviation] from "daily" images were 25.4 [0.2]°C for the digits and 28.4 [0.5]°C for the dorsum, while during RP attacks temperatures were: 22.3 [0.1]°C for the digits and 27.4 [0.9]°C for the dorsum. Including data from only those patients who imaged RP attacks (n=9), the mean [SD] within-patient temperature difference (non-attack images minus RP attacks) for the digits was 3.9 [3.5] °C. That is patients fingers were, on average almost 4 degrees colder during RP attacks than their normal state.
These results demonstrate that mobile phone thermography is a feasible method, including as rated by patients, for collecting rich, quantitative data about RP and importantly including RP episodes outside the clinic or hospital setting. The ability to detect differences in temperature due to RP attacks may enable new, sensitive outcome measures for clinical trials in RP. Further work on the sensitivity of this method to temperature changes induced by (for example) the introduction of vasodilator therapy is now required
REC name
North of Scotland Research Ethics Committee 2
REC reference
21/NS/0042
Date of REC Opinion
30 Mar 2021
REC opinion
Favourable Opinion