Biomedical Engineering Reference
In-Depth Information
Fig. 1.47.
Time-sequentially subtracted thermograms after cold-water immersion
stress to both hands of a Raynaud's syndrome patient.
a
The upper row of images
shows, from left to right, the baseline thermogram (0), directly after immersion
in 4
◦
C water for 10 s (1), 5 min after immersion (2), 10 min after immersion
(3), 20 min after immersion (4), 30 min after immersion (5), and 1 hour after
immersion (6). Before applying the cold-water immersing stress, we cannot detect
the abnormal temperature pattern. However, after applying the load, we can analyze
each finger condition precisely. If we apply image subtraction to the thermogram, we
can find the difference in the blood-flow recovery for each finger.
b
Time-sequentially
subtracted thermograms: [(a)2
−
(a)1] (
upper left
), [(a)3
−
(a)2] (
upper right
), [(a)4
−
(a)3] (
lower left
), and the same image of (a)5 in the
lower right
image. However,
in the cold-water immersing test, not only the skin surface temperature but also
the deep body temperature usually change. Thus, many parameters in (1.6)-(1.11)
might also change. Considering the equations, we should use a milder thermal load
than in this trial
