A Novel Approach to the Detection and Treatment of Raynaud`s

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A Novel Approach to the Detection and Treatment of
Raynaud’s Phenomenon: Using Non-invasive Methods
Danny Clegg1, Andrew Heusch2, Lee McCarthy2, Peter W McCarthy1
1Welsh
Institute of Chiropractic & Faculty of Advanced Technology, University of Glamorgan, Treforest, Pontypridd, CF37 1DL, UK
2Tonus
Europe Limited, Tredegar Business Park, Tredegar, NP22 3EL
Experimental results
Introduction
Raynaud’s phenomenon, named after French Physician Maurice Raynaud, is a microcirculatory disorder,
usually involving the hands and fingers. It is thought to affect 10-20 % of the adult population, involving a
higher number females1. Typical symptoms include discolouration, numbness, tingling and pain, with more
severe cases involving ulceration and necrosis; making Raynaud’s phenomenon a potentially debilitating
condition. Symptoms usually manifest in response to cold, vibration or emotional triggers, thus experimental
studies to date have typically incorporated cold provocation tests around 10 oC 2,3.
Current studies show that there are potential genetic/secondary sites of endothelial damage responsible for
symptom manifestation4. Concurrent with this thinking, more recent and novel approaches to diagnosis have
involved the use of angiography to map out the exact location of vascular destruction, providing platform for a
higher degree of specificity when considering a new treatment approach5.
Insulated gloves are a common non-invasive approach to management of Raynaud’s, with a range of batterypowered heated gloves already available. However, the Raynaud’s and Scleroderma Association (UK) have
suggested that many of these gloves have major design flaws such as: exposed wires, excessive mass and
bulkiness6. To the author’s knowledge, of all gloves marketed as being for sufferers of “Raynaud’s”, only
“Thermoflow” Far Infra Red (FIR) gloves have research evidence (a Randomised Controlled Trial : RCT) to
substantiate their claims7.
Aim
To determine if the design of gloves targeting Raynaud’s sufferers can be improved.
The following charts and images display the results of each experiment
Heat pad testing: Heat pads elicited similar behaviours when
tested using the calibrated sensors (sample frequency 1kHz).
Peak temperatures varied by 1 oC between heat pads, and the
highest peak temperature was 41.9 oC. The mean heat loss from
peak temperature was -3.8 oC after 45 minutes, and the greatest
individual heat loss was 5 oC by pad 2.
Materials (gloves) testing: The graph shows the mean
temperature changes taken from 3 experiments.
Peak
temperatures varied by 3.5 oC. Each pad elicited a higher
peak temperature when encased by a glove. The highest
peak temperature was 45 oC, elicited by glove 2 (mid-range
windproof). The lowest mean heat loss from peak to 45
minutes was -2.4 oC, elicited by glove 1 (basic wool/lycra
glove).
Combined technologies prototype test:
The IR image to the left shows a heat pad
inside the FIR glove, and the image to the
right shows a heat pad inside the prototype.
Both images were taken after 20 minutes of
activation. The prototype retained a greater
amount of heat during this initial testing.
Approach taken
Research and source available materials with high heat-retentive properties. Research design of currently
available materials and Raynaud’s gloves. Develop a scientifically valid methodology for studying heat
retention properties of materials: incorporating infra-red camera, reusable heat pads and traceably calibrated
heat sensors. Create and test prototypes incorporating new materials aimed at increasing heat-retention.
Study description
infra-red thermography: The images to
the left show 2 volunteers with a history of
Raynaud’s phenomenon. The images to
the right show thermographs of normal
hands. There was a greater DDD recorded
in subjects with Raynaud’s phenomenon
when compared to normal hands.
The table below indicates the different experiments used to produce the
methodology with the greatest degree of accuracy.
Conclusion and further work
Table 1: Experimental method description
Experiment
Method
1. Heat Pad Test
Heat pads were activated and temperature changes
recorded using different equipment hand held IR
thermometer; temperature probe; IR camera;
calibrated temperature sensors. IR camera and
sensors were found to have greatest degree of
accuracy.
2. Testing heat pads
inside different
materials
3 gloves were tested (basic wool/lycra; mid-range
windproof; FIR ceramic impregnated). Heat pads
were selected at random, activated, and encased
inside each. IR images and sensor recordings
were taken to record peak temperature reached,
and heat loss over time.
3. Technologies
Material was selected to be incorporated into a
combined to create first prototype based on the previous tests. This
prototypes for testing
prototype is currently being tested using the same
methodology as the other gloves.
4. Analysis of
temperature differences
in the hands of
Raynaud’s sufferers
using infra-red
thermography
Student and academic staff volunteers from the
Chiropractic course had their hands assessed by
taking an image of the dorsum of their hands in a
o
room with a controlled temperature of 23 C.,
following a 20 minute period to aclimatise. The
distal-dorsal difference (DDD) was calculated
8
from the nail bed to the dorsum of the hand .
System description
1. Heat pad testing: Different heat pads elicit a different peak temperature and varying times to reach it, suggesting
possible chemical impurities. The most effective method for recording temperature change was IR
camera and calibrated temperature sensors. Hand-held IR and probe thermometers proved
inconsistent.
2. Materials (gloves) testing: Heat pads retained heat for longer periods of time when encased in different materials.
The most effective glove in terms of heat retention, was surprisingly the wool/lycra glove.
This was the thickest of the materials, suggesting that the most influential factor for heat
retention was material thickness, and not composition.
3. Combined technologies prototype test: This was only an initial test to gain a visual perspective, and the initial result
was that the prototype was able to retain heat for a longer period of time.
However this needs to be tested in the same way as the other materials,
using calibrated sensors, and further conclusions made.
4. infra-red thermography of the hands: Volunteers with Raynaud’s phenomenon had a greater DDD than normal hands.,
consistent with the current literature8. This suggests that this imaging modality is a
useful non-invasive approach when conducting further studies.
The next step will be to continue testing the prototypes already created and continue sourcing materials which will further
improve heat retention. Any subsequent study involving human participants will use IR thermography for assessment.
Acknowledgements: Danny Clegg is on a KESS funded MRes programme
Special thanks to Chiropractic students Stewart Bennett, Elizabeth James and Cinzia Monni for recording the
IR images
References
[1] Silman, A., Holligan, S., Brennan, P., Maddison P. (1990). Prevalence of Symptoms of Raynaud’s Phenomenon in General Practice. BMJ, 301: 590-592
[2] Pelmear, P.L., Roos, J., Leong, D., Wong, L. (1987). Cold Provocation Test Results from a 1985 Survey of Hard-rock Miners in Ontario. Scand J Work Environ Health, 13: 343-347
[3] Thompson, A., House, R., Manno M. (2007). Assessment of the Hand-arm Vibration Syndrome: Thermometry, Plethysmography and the Stockholm Workshop Scale. Occupational Medicine, 57: 512-517
[4] García-Carrasco M,, Jiménez-Hernández, M,, O. Escárcega, R,, Mendoza-Pinto, C,, Pardo-Santos, R., Levy, R,, Galarza Maldonado, C.,Pérez Chávez, G.,, Cervera, R. (2008). Treatment of Raynaud’s Phenomenon. Autoimmunity Reviews, 8: 62-68
[5] Kim, Y.H., Siew-Weng, Ng., Heung, S.S. and Hee, C.A. (2011). Classification of Raynaud’s Disease Based on Angiographic Findings. Journal of Plastic, Reconstructive and Aesthetic Surgery, xx: 1-9
[6] Mawdsley, A. H. (2011). Letter detailing feedback on currently available gloves from the chief executive off the Raynaud’s and Scleroderma Association (UK), dated 23rd February, 2011
[7] Ko, G.D., Berbrayer, D. (2002). Effect of Ceramic-Impregnated “Thermoflow” Gloves on Patients with Raynaud’s Syndrome: Randomized, Placebo-Controlled Study. Alternative Medicine Review, 7(4): 328-335
[8] Anderson, M.E., Moore, T.L., Lunt, M. And Herrick, A.L. (2006). The ‘Distal–Dorsal Difference’: a Thermographic Parameter by Which to Differentiate Between Primary and Secondary Raynaud’s Phenomenon. Rheumatology, 46: 533-538
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