| Institution: | 1. Fondazione Policlinico Universitario Agostino Gemelli IRCSS, Rome, Italy;2. Department of Mechanical and Aerospace Engineering, Sapienza University of Rome, Italy;3. IRCCS Fondazione Don Carlo Gnocchi, 50143 Florence, Italy;4. IRCCS Fondazione Don Carlo Gnocchi, 20121 Milan, Italy;5. Department of Geriatrics, Neurosciences and Orthopaedics, Università Cattolica del Sacro Cuore, 00168 Rome, Italy;6. Department of Economics, Engineering, Society and Business Organization (DEIM), University of Tuscia, 01100 Viterbo, Italy;1. Department of Neurosurgery, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan;2. National Hospital Organization Shibukawa Medical Center, Shibukawa, Japan;1. Department of Neurosurgery, Rush University Medical Center, Chicago, Illinois, USA;2. Section on Movement Disorders, Department of Neurology, Rush University Medical Center, Chicago, Illinois, USA;1. Division of Neurosurgery, University of British Columbia, Vancouver, Canada;2. Department of Stereotactic and Functional Neurosurgery, Heinrich-Heine University, Düsseldorf, Germany |
| Abstract: | ObjectiveDuring deep brain stimulation (DBS) surgery, we analysed somatosensory evoked potentials (SSEPs) using microelectrode recordings (MERs) in patients under general anaesthesia.MethodsWe obtained MERs from 5 patients with refractory epilepsy. Off-line analysis isolated local field potentials (LFPs, 2–200 Hz) and high frequency components (HFCs, 0.5–5 kHz). Trajectories were reconstructed off-line.ResultsThe ventral caudate (V.c.) nucleus was most frequently recorded from (171 mm). Very high frequency oscillations (VHFOs) were recorded up to 8 mm in length from all 4 electrodes but were most frequently recorded from the V.c. The properties of VHFOs were similar among all nuclei (frequency >1500 Hz, amplitude ～3 µV, starting time ～14 ms, duration 8–9 ms). Consecutive recordings did not show any synchronization or propagation, but a new kind of potential (high frequency oscillation, HFO) appeared abruptly inside the V.c. (frequency = 848 ± 66 Hz, amplitude = 5.2 ± 1.8 µV starting at 17.7 ± 0.5 ms, spanning 3.4 ± 0.3 ms).ConclusionsVHFOs are widely extending and cannot be ascribed to the V.c. HFOs in patients under general anaesthesia can serve as a landmark to identify the V.c. in thalamic DBS surgery.SignificanceThalamic processing involves nuclei other than the V.c, and HFO can be used to improve DBS surgery. |
