Clinical Application of Laser Speckle Flowgraphy to Assess Changes in Blood Flow to the Foot After a Lumbar Sympathetic Ganglion Block: A Case Report

BACKGROUND: The lumbar sympathetic ganglion block (LSGB) has been used as a diagnostic and therapeutic procedure for treating pain conditions such as neuropathic and ischemia-related pain, affecting the lower extremities. In general, an increase in skin temperature is useful in confirming the effectiveness of the sympathetic nerve block in clinical settings. However, the assessment of skin temperature in patients with peripheral arterial disease (PAD) occasionally provides false negatives. CASE PRESENTATION: A novel technology, laser speckle flowgraphy (LSFG) enables noninvasive quantitative and qualitative blood flow assessments. LSFG is a novel neuro-monitor for quantitative blood flow detection in the optic nerve head during cardiac surgery. Herein, we report on measuring foot blood flow using LSFG before and after LSGB in a PAD patient. This research aimed to determine whether LSFG could detect any improvement in the dynamics of foot blood flow after an LSGB in a situation where changes in skin temperature alone could not determine the procedure’s outcome. CONCLUSION: LSFG can be used to assess blood flow changes in a foot with PAD, following a LSGB.