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of Ultrasound, which is on the order of microseconds. Multiple
source-detectors CT can also provide real-time imaging with
a temporal resolution of milliseconds. However, MRI has less
temporal resolution as a result of the prolonged relaxation
period, which can be on the order of hundreds of milliseconds
to seconds.
21.5.4 Safety
Like ultrasound and MRI, PAT uses nonionizing illumination
sources, including laser and RF waves. In clinical applications,
the illumination intensity of PAT can be set to within accepted
safety standards. CT, however, uses ionizing ...