The analysis of necessity of transcranial electric stimulation motor evoked and somatosensory evoked potential monitoring during the growing rod lengthening surgery

English Keywords:Scoliosis  Growing rod technique  Motion evoked potential  Somatosensory evoked potential

English Abstract:

  【Abstract】 Objectives: To analyze the necessity of transcranial electric stimulation motion evoked potential (MEP) and somatosensory evoked potential(SEP) during the growing rod lengthening surgery. Methods: From October 2010 to January 2015, MEP and SEP monitoring were performed simultaneously during 141 growing rod lengthening surgeries. C3 and C4(international 10-20 system) were stimulated to elicit MEP and compound muscle action potentials were recorded from distal limbs. The bilateral tibial nerves were stimulated to record SEP. Alterations with MEP wave amplitude decreasing more than 75% and SEP amplitude decreasing more than 50% or latent period extending by 10% were diagnosed as positive changes. Results: Combined SEP and MEP monitoring was performed in all 141 growing rod lengthening surgeries. Success rate of MEP and SEP recording was 98.6% and 99.3%, respectively. There were two cases(1.4%) having failed SEP recording and one case in MEP(0.7%). All patients were successfully recorded by at least one kind of monitoring. There were no positive alterations and all recordings were true negative in both MEP and SEP. Conclusions: Growing rod lengthening surgery is a kind of simple and safe procedure, but MEP and SEP are used to monitor neurological function can provide the security evaluation index objective for the growing rod lengthening surgery.