Two-Dimensional Oxygen Saturation Imagery for Determining Microcirculation Promotion by Nerve Conduction Testing

Nerve compression or blocked blood circulation can cause numbness in the fingers, hands, arms, feet, and legs; moreover, nerve compression is the cause of carpal tunnel syndrome, a common ailment. Nerve compression is often analyzed through a nerve conduction study (NCS), in which electrical stimulation is used to determine the nerve conduction velocity and the region of nerve compression. However, electrical stimulation can also promote blood circulation, increasing oxygen saturation (SpO
2
). This study developed a method that entails using two-dimensional (2D) SpO
2
images to analyze the effectiveness of microcirculation promotion in the hand after electrical stimulation performed using NCS equipment. The stimulation current and duration were varied, and SpO
2
was measured after each stimulus (count). The results revealed that SpO
2
tended to increase before returning to baseline. In one experiment, SpO
2
increased by approximately 3%–4% after three counts and returned to baseline after four more counts. The proposed 2D SpO
2
observation method was effective for determining the influence of the NCS process on microcirculation promotion, and the results can be used by clinical rehabilitation physicians for limb numbness treatment.