척수 종양 제거 술 중 운동유발전위의 호전과 근력 호전의 관계

Abstract

Objective: To evaluate whether the increase of the amplitude of motor evoked potentials (MEPs) during surgery can imply favorable prognosis postoperatively in spinal cord tumor surgery. Method: MEPs were monitored in patients who underwent spinal cord tumor surgery between March 2016 and March 2018. Amplitude changes at the end of monitoring compared to the baselines in limb muscle were analyzed. Minimum and maximum changes were set to MEPmin (%) and MEPmax (%). Strengths of bilateral 10 key muscles which were documented a day before (Motorpre), 48 h (Motor48h) and 4 weeks (Motor4wk) after the surgery were reviewed. Results: Difference of Motor48h from Motorpre (Motor48h-pre) and Motor4wk from Motorpre (Motor4wk-pre) positively correlated with MEPmin, suggesting that smaller the difference of MEPs amplitude, less recovery of muscle strength. There was a negative correlation between the amount of bleeding and MEPmin, indicating that the greater the amount of bleeding, the smaller the MEPmin, implying that MEPs amplitude is less likely to improve when the amount of bleeding is large. It also showed significant difference between patients with improved or no change of motor status and patients with motor deterioration after surgery according to anatomical tumor types. Conclusion: Improve of muscle strength was less when the increase of MEPs amplitude was small, and improvement of MEPs amplitude was less when the amount of bleeding was large. Correlation between changes of status of muscle strength after surgery and tumor types was observed. With amplitude increase in MEPs monitoring, restoration of muscle strength can be expected.