Functional brain mapping of eloquentcortex is an essential step when planning resective brain surgeries. Mapping techniques like electrical cortical stimulation (ECS)123and functional magnetic resonance imaging (fMRI)1 are well-established in clinical practice. However, these procedures might be demanding for the patient or provide limited spatial and temporal resolution. ECS can also trigger accidental seizures. A passive mapping procedure based on task-related activation of the high-gamma frequency band (>60 Hz) in electrocorticographic (ECoG) signals promises fast and precise mapping without the risk of causing pain or seizures14. This mapping procedure has repeatedly demonstrated that it can accurately identify cortical regions related to receptive56 and expressive67 language function, motor function5689 and the somatosensory system5.
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5. Kapeller, C. et al. CortiQ-based Real-Time Functional Mapping for Epilepsy Surgery: J. Clin. Neurophysiol. 32, e12–e22 (2015).
6. Ogawa, H. et al. Rapid and Minimum Invasive Functional Brain Mapping by Real-Time Visualization of High Gamma Activity During Awake Craniotomy. World Neurosurg. 82, 912.e1–912.e10 (2014).
7. Taplin, A. M. et al. Intraoperative Mapping of Expressive Language Cortex Using Passive Real-Time Electrocorticography. Epilepsy Behav. Case Rep. (2016). doi:10.1016/ j.ebcr.2016.03.003
8. Brunner, P. et al. A practical procedure for real-time functional mapping of eloquent cortex using electrocorticographic signals in humans. Epilepsy Behav. 15, 278–286 (2009).
9. Roland, J., Brunner, P., Johnston, J., Schalk, G. & Leuthardt, E. C. Passive real-time identification of speech and motor cortex during an awake craniotomy. Epilepsy Behav. 18, 123–128 (2010).
Face Recognition/Place Area
Face Recognition/Place Area
Intra Operative Monitoring
Epilepsy Neuro Monitoring (Bedside)
Functional Brain Mapping with ECoG
Functional Brain Mapping with ECS
Functional Brain Mapping with fMRI
Real-time Feedback Application or BCI
Schalk, G., Kapeller, C., Guger, C., Ogawa, H., Hiroshima, S., Lafer-Sousa, R., Saygin, Z.M., Kamada, K. and Kanwisher, N., 2017. Facephenes and rainbows: Causal evidence for functional and anatomical specificity of face and color processing in the human brain. Proceedings of the National Academy of Sciences, p.201713447.
Ogawa H, Kamada K, Kapeller C, Prueckl R, Takeuchi F, Hiroshima S, Anei R, Guger G, Clinical Impact and Implication of Real-Time Oscillation Analysis for Language Mapping, World Neurosurgery, Available online 28 September 2016, ISSN 1878-8750
Tamura Y, Ogawa H, Kapeller C, Prueckl R, Takeuchi F, Anei R, Ritaccio A, Guger C, Kamada K, Passive language mapping combining real-time oscillation analysis with cortico-cortical evoked potentials for awake craniotomy. 2016, Journal of Neurosurgery, 1.
Ritaccio, A., Matsumoto, R., Morrell, M., Kamada, K., Koubeissi, M., Poeppel, D., ... & Schalk, G. (2015). Proceedings of the Seventh International Workshop on Advances in Electrocorticography. Epilepsy & Behavior, 51, 312-320.
Christoph Kapeller (2015): Online Control of a Humanoid Robot through Hand Movement Imagination using CSP and ECoG based Features. Presentation.
Kapeller C, Korostenskaja M, Prueckl R, Chen PC, Lee KH, Westerveld M, Salinas CM, Cook JC, Baumgartner JE, Guger C., CortiQ-based Real-Time Functional Mapping for Epilepsy Surgery. J Clin Neurophysiol. 2015 Jun;32(3):e12-22. doi: 10.1097/WNP.0000000000000131
Kapeller C, Kamada K, Ogawa H, Prückl R, Kunii N, Schnürer A, Guger C. P87. Expressive and receptive language mapping using ECoG and ECS. Clinical Neurophysiology. 2015 Aug 31;126(8):e146.
Kapeller C, Schneider C, Kamada K, Ogawa H, Kunii N, Ortner R, Prückl R, Guger C. Single trial detection of hand poses in human ECoG using CSP based feature extraction. In2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society 2014 Aug 26 (pp. 4599-4602). IEEE.
Kapeller, C., Kamada, K., Ogawa, H., Prueckl, R., Scharinger, J., & Guger, C. (2014). An electrocorticographic BCI using code-based VEP for control in video applications: a single-subject study. Frontiers in systems neuroscience, 8.
Prueckl, R., et al. "Real-Time Software for Functional Mapping of Eloquent Cortex Using Electrocorticography." Biomedical Engineering/Biomedizinische Technik (2013).
Roland, Jarod, et al. "Passive real-time identification of speech and motor cortex during an awake craniotomy." Epilepsy & Behavior 18.1 (2010): 123-128.
Kapeller, Christoph; Kamada, Kyousuke; Ogawa, Hiroshi; Kunii, Naoto; Prueckl, Robert; Kawai, Kensuke; Schalk, Gerwin; Guger, Christoph. Comparison of ECoG and ECS Language Mapping with High-Density Electrodes. 2013 IEEE Neural Engineering Short Papers No. 0521.
Prueckl R, Kapeller C, Potes C, Korostenskaja M, Schalk G, Lee KH, Guger C., CortiQ - clinical software for electrocorticographic real-time functional mapping of the eloquent cortex. Conf Proc IEEE Eng Med Biol Soc. 2013;2013:6365-8. doi: 10.1109/EMBC.2013.6611010.
Korostenskaja, Milena, et al. "Real-Time Functional Mapping With Electrocorticography in Pediatric Epilepsy Comparison With fMRI and ESM Findings." Clinical EEG and neuroscience 45.3 (2014): 205-211.
Kamada K, Ogawa H, Kapeller C, Prueckl R, Guger C., Rapid and low-invasive functional brain mapping by realtime visualization of high gamma activity for awake craniotomy. Conf Proc IEEE Eng Med Biol Soc. 2014;2014:6802-5. doi: 10.1109/EMBC.2014.6945190.
Ogawa H, Kamada K, Kapeller C, Hiroshima S, Prueckl R, Guger C., Rapid and minimum invasive functional brain mapping by real-time visualization of high gamma activity during awake craniotomy. World Neurosurg. 2014 Nov;82(5):912.e1-10. doi: 10.1016/j.wneu.2014.08.009. Epub 2014 Aug 7. PMID: 25108295.
Brunner, Peter, et al. "A practical procedure for real-time functional mapping of eloquent cortex using electrocorticographic signals in humans." Epilepsy & Behavior 15.3 (2009): 278-286.
G. Schalk, E. C. Leuthardt, P. Brunner, J. G. Ojemann, L. A. Gerhardt, J. R. Wolpaw, Real-time detection of event-related brain activity, Neuroimage 43 (2) (2008) 245–249.
Location: University of Tokyo, Japan
Reference: Kapeller, C., Kamada, K., Ogawa, H., Prückl, R., Kunii, N., Schnürer, A., & Guger, C. (2015). P87. Expressive and receptive language mapping using ECoG and ECS. Clinical Neurophysiology, 126(8), e146.
The study included ECS and ECoG mapping with an epileptic patient with 236 subdural electrodes who underwent neuro-monitoring. The receptive and expressive language areas were each covered by a high-density subdural electrode grid with inter-electrode distance of 5 mm and conductive area of 1.5 mm. The ECoG mapping was performed with the real-time mapping system cortiQ (g.tec, Austria), which detects task related changes of gamma-band oscillations3. In order to activate the expressive language area, a picture naming task was performed during both mapping procedures. Additionally, a listening task was performed during the cortiQ mapping, to activate the receptive language area. The cortiQ mapping was repeated two times to ensure stable mapping results.
Location: Asahikawa Medical University, Japan
Reference: A Case Study on Functional Brain Mapping: Comparison ECoG, ECS and fMRI based Mapping Techniques, Not published - presented at OHBM 2014 (Poster 2190)
Location: Florida Hospital for Children, Orland, USA
Reference: Kapeller, C., Korostenskaja, M., Prueckl, R., Chen, P. C., Lee, K. H., Westerveld, M., ... & Guger, C. (2015). CortiQ-based Real-Time Functional Mapping for Epilepsy Surgery. Journal of clinical neurophysiology, 32(3), e12-e22.
Functional magnetic resonance imaging, ESM, and cortiQ were used to determine localization of eloquent motor, sensory, and language cortex. The patient sat in front of a screen and was instructed to relax and remain as still as possible before the paradigm was started. After setup and investigation of raw data, the mapping session started. To identify particular functional regions over the cortex, the patient had to follow the instructions presented on a monitor. Specifically, we wanted to explore the motor and somatosensory area of the left hand, as well as the receptive language area (Wernicke’s). The patients went through a paradigm that consisted of 4 tasks: (1) stick out the tongue, (2) open/close the left hand, (3) feel tactile stimuli (presented via a brush) that were applied to the palm and inner side of the Fingers of the left hand, and (4) a speech comprehension task where the patient listened to a story. After an initial delay of 10 seconds, where no data were collected for analysis, the paradigm started with a 15-second baseline period, in which the instruction for the patient presented on the display was “relax”. Each task was repeated three times.
The mission is to provide the most accurate, reliable and quick functional mapping system to minimize the burden for patients and for neurosurgeons.