Reliability of infrared thermal imaging in evaluating the degree of stellate ganglion block

Objective To evaluate the reliability of infrared thermal imaging techniques for assessment of stellate ganglion block. Methods Total 36 patients with subjective tinnitus in our hospital were chosen as the research objects. A stellate ganglion block was performed in affected side under the guidance of ultrasound. The therapeutic effect (G) was recorded as:cure (4 points):tinnitus disappeared; significant (3 points):tinnitus alleviated dramatically; effective (2 points):minimal response; invalid (1 point):no remission or exacerbation. The degree of blepharoptosis (L):significant (3 points):can be observed to significantly ptosis; minor (2 points):to slight ptosis can be observed, but not obvious; invalid (1 point):no ptosis by comparison of left and right sides. Infrared thermal imaging instrument was used to record the face infrared thermal imaging of patients before operation (Picture 1) and 10min after operation (Picture 2). The maximum temperature difference between the symmetry facial regions was recorded as ΔT. Linear correlation of G value with L value and ΔT (℃) was analyzed. Results The therapeutic effect:cure 10/36, significant 17/36, effective 7/36 and invalid 2/36, the G w value as 2.97±0.85; The degree of upper eyelid droop (L):significant 7/36, minor 17/36 and invalid 12/36, the L value was 1.92±0.73; Postoperative ΔT was (1.27±0.51)℃. There was no correlation between value G and value L, and the correlation coefficient was 0.037 (P>0.05); There was correlation between value G and Δ T (℃), and the correlation coefficient was 14.016 (P<0.05). Conclusion Horner's syndrome cannot give an objective evaluation for the degree of stellate ganglion block; however, the infrared thermal imaging is an reliable and useful technique for assessment of the degree of stellate ganglion block.