Aliasgar Moiyadi1, Parthiban Velayutham2, Prakash Shetty2, Kathleen Seidel3, Amit Janu4, Venkatesh Madhugiri5, Vikas Kumar Singh2, Aditya Patil2, Robin John2. 1. Neurosurgical Services, Department of Surgical Oncology, Tata Memorial Centre, Mumbai, India; Homi Bhabha National University, Mumbai, India. Electronic address: aliasgar.moiyadi@gmail.com. 2. Neurosurgical Services, Department of Surgical Oncology, Tata Memorial Centre, Mumbai, India; Homi Bhabha National University, Mumbai, India. 3. Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland. 4. Homi Bhabha National University, Mumbai, India; Department of Radiodiagnosis, Tata Memorial Centre, Mumbai, India. 5. Department of Neurosurgery, Adyar Cancer Institute, Chennai, India.
Abstract
BACKGROUND: Subcortical motor mapping is crucial to ensure preservation of motor tracts during resections of tumors. Continuous dynamic mapping using a modified monopolar suction probe is a novel and effective way of achieving this goal. We describe our experience using this technique. METHODS: Forty patients were operated on between June 2017 and February 2018. Transcranial electric stimulation (TES) and direct cortical strip (DCS) motor evoked potentials (MEPs) were monitored. Subcortical stimulation (SCS) mapping was attempted in all cases by adapting the technique using a monopolar suction stimulator. Neurologic outcomes and extent of resection were analyzed. RESULTS: Motor fibers were between 0 and 7.6 mm away from the tumor boundaries in 26 patients. TES MEP were monitored in all patients. DCS MEPs were attempted in 31 and successfully monitored in 26 patients. SCS using the monopolar suction probe worked in all patients except one. SCS elicited no responses at 15-mA motor thresholds in 16 patients. The motor threshold ranged from 3 to 10 mA in the remainder. Overall, MEP changes were noted in 5 patients. Ten patients experienced neurologic worsening (6 transient, 3 prolonged, and 1 delayed). There was no permanent deficit at 3 months. DCS MEPs predicted neurologic worsening better than did TES MEPs. Radical resections were achieved in 68%. Neuromonitoring inputs resulted in premature termination of resection in 14 patients (35%). Radical resections (near-total resections) were still achieved in 8 of the 14 patients. CONCLUSIONS: Continuous dynamic subcortical mapping is a reliable method to map the motor tracts. This process is crucial to correctly identify truly eloquent tumors and tailor the surgical procedure as per planned goals, maximizing the resections with acceptable morbidity.
BACKGROUND: Subcortical motor mapping is crucial to ensure preservation of motor tracts during resections of tumors. Continuous dynamic mapping using a modified monopolar suction probe is a novel and effective way of achieving this goal. We describe our experience using this technique. METHODS: Forty patients were operated on between June 2017 and February 2018. Transcranial electric stimulation (TES) and direct cortical strip (DCS) motor evoked potentials (MEPs) were monitored. Subcortical stimulation (SCS) mapping was attempted in all cases by adapting the technique using a monopolar suction stimulator. Neurologic outcomes and extent of resection were analyzed. RESULTS: Motor fibers were between 0 and 7.6 mm away from the tumor boundaries in 26 patients. TES MEP were monitored in all patients. DCS MEPs were attempted in 31 and successfully monitored in 26 patients. SCS using the monopolar suction probe worked in all patients except one. SCS elicited no responses at 15-mA motor thresholds in 16 patients. The motor threshold ranged from 3 to 10 mA in the remainder. Overall, MEP changes were noted in 5 patients. Ten patients experienced neurologic worsening (6 transient, 3 prolonged, and 1 delayed). There was no permanent deficit at 3 months. DCS MEPs predicted neurologic worsening better than did TES MEPs. Radical resections were achieved in 68%. Neuromonitoring inputs resulted in premature termination of resection in 14 patients (35%). Radical resections (near-total resections) were still achieved in 8 of the 14 patients. CONCLUSIONS: Continuous dynamic subcortical mapping is a reliable method to map the motor tracts. This process is crucial to correctly identify truly eloquent tumors and tailor the surgical procedure as per planned goals, maximizing the resections with acceptable morbidity.
Authors: Luca Viganò; Vincenzo Callipo; Marta Lamperti; Marco Rossi; Marco Conti Nibali; Tommaso Sciortino; Lorenzo Gay; Guglielmo Puglisi; Antonella Leonetti; Gabriella Cerri; Lorenzo Bello Journal: Front Oncol Date: 2022-09-29 Impact factor: 5.738
Authors: Tizian Rosenstock; Mehmet Salih Tuncer; Max Richard Münch; Peter Vajkoczy; Thomas Picht; Katharina Faust Journal: Front Oncol Date: 2021-05-21 Impact factor: 6.244