Dados do Trabalho

Título

INTRAOPERATIVE ELECTROMYOGRAPHY IN FUNCTIONAL STEREOTACTIC SURGERY

Introdução

Micro registration techniques are used in many centers to confirm localization of stereotactic target in functional neurosurgery but is invasive and expensive, also Patient cooperation in macroelectrodes stimulation alone may be difficult to differentiate from spontaneous and dyskinetic movements.

Objetivo

The aim of this study is show our experience in use intraoperative electromyography (IEMG) during stereotactic internal globus pallidus (GPi) deep brain stimulation (DBS) and pallidotomy for Parkinson’s disease and dystonia, to help care to avoid capsular injury while maximizing improvement of rigidity, bradykinesia and dystonic movements.

Método

Seventy-two consecutive stereotactic procedures were performed patients with had a clinical diagnosis of Parkinson's disease or dystonia for at least 5 years prior to surgery. Stereotaxic procedure was targeted with neuroanatomical localization. Intraoperatively the target was confirmed with macrostimulation, before radiofrequency pallidotomy or DBS electrode implant, with stimulation at 5, 50 and 100 Hz thresholds for detection of IEMG. Responses of IEMG were consistently seen prior to visual observation of patient muscle activity. Timing of IEMG response relative to stimulus aided in differentiating stimulus-related movement from spontaneous tremor. Resting spontaneous IEMG activity was seen to decrease as rigidity was improved by stimulation.

Resultados

The rates of immediate improvement of rigidity and tremor were better than those observed in the routine. There were no major complications. The surgical time was increased in range of 4 - 12 minutes. The macrostimulation with EMG showed internal capsule signals, suggesting trajectory correction in 9 patients. Fifth seven patients showed immediate postoperative neurologic improvement. Two patients developed a postoperative transient minimal contralateral facial paresis or hemiparesis due to minimal hemorrhage at the lesion site, solved six months after surgery with conservative management. The follow up time was 36 months and UPDRS differences were 32% for UPDRS III and UDRS by 62.5% .

Conclusão

IEMG have have elevated the level of confidence in the safety becouse contributes significantly to the stabilization of vital signs during surgery, preventing systemic arterial pressure variations, most common cause of bleeding during surgery in the fully awake patient.



Electromyography, intraoperative, stereotaxy