CUTTING-EDGE BRAIN MAPPING FOR ENHANCED EPILEPSY AND TUMOR SURGERY
Utilizing ECoG and advanced high-gamma mapping, cortiQ improves surgical accuracy by identifying crucial brain areas for safer resections, reducing the risk of neurological deficits in epilepsy and brain tumor patients
cortiQ offers an innovative approach to brain mapping, specifically designed for use with epilepsy and brain tumor patients. By leveraging electrocorticographic (ECoG) activity, cortiQ identifies functional brain areas activated during tasks such as motor movements or speech production. cortiQ offers an enhanced surgical precision and safety for neurologists and neurosurgeons to accurately localize eloquent brain areas, providing crucial information for surgical resection. This minimizes the risk of neurological deficits, ensuring safer outcomes for patients.
- High-Gamma Mapping (CQ). Perform high-gamma mapping with ECoG or stereo-EEG to identify key brain regions using the advanced CQ module.
- White Matter Exploration. Cortical mapping in white matter for a deeper understanding of connectivity and function within the brain’s communication pathways.
- Electrical Stimulation (ECS). Stimulate the identified regions using the ECS module with up to 15 mA to confirm functional areas.
- Cortico-Cortical Evoked Potentials (CCEP). Map brain networks efficiently by stimulating pairs of electrodes without artifacts.
- Somatosensory Evoked Potentials (SEP). Quickly identify the central sulcus for more accurate surgical planning.
- High Fidelity Evoked Potentials. Minimize stimulation artifacts with a DC-coupled amplifier.
- The Right Montage: Quickly set up 2D recordings, use the 3D Montage Creator for localization, or import existing coordinates.
- Impedance Measurement: Analyze frequency-dependent impedance to better understand the electrode-tissue interface.
This process significantly reduces mapping time, decreases after-discharges and seizures, improves precision, and ultimately enhances survival times for tumor patients.
- CQ: High-gamma mapping with ECoG or stereo-EEG
- ECS: Electrical cortical stimulation with up to 15 mA
- Z: Impedance measurement of ECoG grids and depth electrodes
- DECS: Direct electrocortical stimulation with a hand-held probe
- CCEP: Cortico-cortical evoked potentials (research mode)
- SEP: Somatosensory evoked potentials (research mode)
Experience the future of brain mapping with cortiQ 2.0, where cutting-edge technology meets unparalleled precision and safety in neurosurgical procedures.
| Real-time brain mapping in the operating room or neuro monitoring unit |
| Integration of high-gamma mapping and ECS in one device |
| Integrated CCEP and central sulcus mapping module |
| Integrated impedance check for ECoG and stereo-EEG |
| Minimize hospital time and costs |
| Rapid mapping procedure |
| Customizable for individual surgical needs |
| Optimize surgical procedures |
| Reduce risks for patients |
| Can be used in very young patients, too |
| FDA cleared and CE123 certified medical product |
| ADC | 24 Bit, one per channel |
| ECoG channels, stereo-EEG channels | 64, 128 or 256 |
| Oversampling | 614.14 kHz to 2.4 kHz |
| Anti-aliasing | Ultra-steep in 2 co-processors |
Passive high-gamma mapping represents a physiologically elegant and clinically relevant paradigm shift for identifying essential cortical functions.
Anthony Ritaccio, PhD, MD - Mayo Clinic, Florida, USA
I use ECoG electrodes for real-time brain mappings to find and interpret functional activity in the brain at the bed-side, and during awake craniotomy for brain surgery. I can reduce electrical cortical stimulations (ECS) to minimize related seizures and shorten clinical examinations. Otherwise, I would miss an opportunity to improve existing brain mapping procedures and learn the bigger picture.
Kyousuke Kamada, PhD, MD - Hokashin Group Megumin Hospital, Sapporo, Japan
cortiQ mapping is based on passive recordings and statistical evaluations of ECoG, rather than on active electrical stimulation and visual observation of behavior. It can be used to map motor, expressive or receptive language, and other functions, and has been shown to have good concordance to results from other imaging techniques. Brain mapping can be achieved in minutes with adults or children, and performed in the extraoperative or intraoperative scenario.
Dr. Christoph Guger - g.tec medical engineering GmbHDIAGNOSIS: EPILEPSY OR BRAIN TUMOR
Epilepsy is a common neurological disorder that affects a large portion of the world population. Many of the affected people can control epileptic seizures with the use of medication, but for around 15–20% of this population, medication is not effective, and some of these patients choose surgery. Brain cancer is another reason for brain surgery. There are various types of brain tumors, and the aim of the surgery is to remove the tumor (or at least parts of it).
BRAIN ANALYSIS: ECOG, STEREO EEG, ECS, FMRI
The cortiQ rapid cortical mapping system by g.tec medical engineering utilizes electrocorticographic (ECoG) signals for fast, precise, and pain-free brain mapping, accurately identifying regions related to language, motor, and sensory functions. This method, combined with quick confirmation using the built-in ECS module, offers a safer alternative to traditional techniques like electrical cortical stimulation (ECS) and fMRI, which can be time-consuming, seizure-inducing, or unreliable.
BRAIN MAPPING BEFORE OR DURING SURGERY
cortiQ is a rapid functional mapping technique using ECoG for epilepsy and brain tumor patients. It helps surgeons identify functional brain regions with high-gamma activity before surgery. cortiQ maps brain regions based on tasks the patient performs, delivering results in 3-5 minutes. Surgeons can customize paradigms to fit surgical needs, and the built-in ECS module confirms the mapped locations by stimulating selected electrode pairs.
BRAIN MAPPING WITH ELECTROCORTICOGRAPHY
For example, if pathological tissue is close to the motor area, cortiQ will ask the patient to move arms, feet or even lips. The brain activity patterns produced during these movements will be transmitted in real-time to cortiQ, notifying the neurosurgeon what parts are important for a certain movement and therefore should remain untouched.
CORTICAL MAPPINGS IN THE OPERATING ROOM
After successful implantation of cortiQ ECoG electrodes, there are two ways of how to perform the brain mapping: intra-operative or bedside. These two approaches open many more opportunities with a minimal risk for the patient. A brand new feature of cortiQ is the real-time 3D visualization of brain activity.
USE CASE: AWAKE SURGERY
The awake surgery case is critical in time. First, a craniotomy is performed to implant the electrodes. Then functional real-time mappings are performed just before the brain tissue resection. Validation with ECS must be done during the surgery.
USE CASE: BEDSIDE
The bedside case usually requires two surgeries. In the first surgery, electrodes will be implanted and functional real-time mappings are performed at the bedside. Validation with ECS can be done at the beside, too. In the second surgery, electrodes will be removed and the affected brain tissue will be resected.
Unlike ECS, cortiQ does not produce artificial seizures and cannot produce pain. However, ECS might be required in some cases.
Therefore, cortiQ can identify neural areas that are “active” in a task decided by the surgeon and thereby provide a fast pre-screening mechanism that might be used for optimized ECS mapping and surgical removal of affected tissue.
- During brain surgery, invasive electrode grids are placed on the cortex or are inserted into the brain covering the specific areas that need to be mapped.
- The central sulcus is identified with the SEP module
- The patient performs preprogrammed tasks, e.g. moving limbs, listening to a story, calculating or speaking, which support the neurosurgeon to get a better understanding of the individual functional regions of the brain.
- cortiQ creates a real-time mapping of the brain, showing what brain areas are active during a specific task.
- ECS is used to confirm the mapping result
- Cortical networks are identified with the CCEP module
- Finally, brain surgery can be prepared and performed safely in record time and with reduced costs.
TEMPORAL DYNAMICS IN THE BRAIN RECORDED WITH CORTIQ
The video shows the temporal dynamics of cortiQ mapping. As soon as the patient sees the instruction the temporal base is activated and few seconds later the motor cortex, the auditory cortex and Wernicke’s area show the functional regions.
CORTIQ 2.0 - HIGH GAMMA MAPPING MODE
This innovative feature transforms brain mapping during tumor and epilepsy surgeries. Patients perform tasks like solving a Rubik’s Cube to activate specific brain regions, with real-time high-gamma signals mapped onto the cortex using color-coded markers. Structured, multilingual tasks and repeated cycles ensure precise, reliable results in just minutes.
CORTIQ 2.0 - ELECTRICAL CURRENT STIMULATION
Step 1: cortiQ 2.0 performs high-gamma mapping. Step 2: Identified regions are stimulated with the ECS module, reducing mapping time, seizures, and improving precision, leading to longer tumor patient survival. During mapping, the patient names pictures while high-gamma analysis identifies regions like the visual cortex and expressive language areas, represented with cortical bubbles. The neurosurgeon then selects electrode pairs for stimulation, adjustable up to 15 mA. If stimulation inhibits object naming, it confirms high-gamma results. The ECS annotation is labeled “expressive language,” shown as a green line, demonstrating the overlap and efficiency of the procedure.
CORTIQ 2.0 - PARADIGM EDITOR
cortiQ 2.0 allows you to set up your own experimental paradigm. The video demonstrates an expressive language mapping paradigm configuration, using scrambled images to record baseline activation versus real images that need to be named. The scrambled and real images are matched for color intensity.
CORTIQ 2.0 - AUTO-SNAP STEREO-EEG ELECTRODES WITH CT IMAGES
cortiQ 2.0 simplifies the process of high-gamma mapping with its user-friendly features. Begin by loading the patient’s CT image, then select the Auto-Select option. Choose the specific stereo-EEG electrode, and the iEEG Montage Creator will automatically place the electrodes. You can then fine-tune the electrode locations using the editor function and start your high-gamma mapping with cortiQ 2.0.
CORTIQ 2.0 - ELECTRODE GRID PLACEMENT
The ECoG grids can be selected from a library and placed by drag-and-drop over the corresponding cortical regions. The key is to position them precisely onto landmarks provided by the underlying picture. Afterwards, the grids are projected onto a 3D mesh of the cortex. In the next step, the patient is instructed to perform certain tasks, while the high-gamma signal is statistically evaluated to indicate cortical regions responsible for the task.
CORTIQ 2.0 - EXPRESSIVE LANGUAGE MAPPING
On the left, the ECoG signals from four cortical grids are displayed. The patient’s task is to quickly name the pictures shown on the screen. In the background, cortiQ performs high-gamma mapping to identify the expressive language region. The video impressively illustrates the temporal dynamics. Initially, the patient observes various objects, activating the temporal base. Here, shapes, colors, black and white images, symbols, or even faces are decoded. Shortly after, Broca’s area is activated, immediately appearing as a bubble.
CORTIQ 2.0 - IMPEDANCE CHECK
cortiQ 2.0 improves the safety and efficiency of impedance measurement for ECoG grids, strips, or stereo-EEG electrodes, addressing concerns with minimal current and quick, simultaneous readings. Accurate electrode quality is essential, as faulty electrodes can degrade data, especially with systems that can’t disable common average reference. cortiQ 2.0 ensures optimal grid attachment by identifying and excluding problematic channels, enhancing mapping precision intraoperatively.
CCEP MAPPING OF THE WHOLE CORTEX
CCEP mapping of the whole cortex in 60 minutes involves automatically selecting electrode pairs to stimulate cortical regions and induce cortico-cortical evoked potentials (CCEPs). The process shows raw ECoG recordings, evoked potentials, and significant N1 RMS responses in red bubbles. Red bubbles near the stimulation electrode indicate artifacts, while remote electrodes map cortical networks. In a study with Dr. Kyousuke Kamada, this technique mapped language networks by stimulating Broca’s area. Identifying pathological CCEPs is essential for interrupting seizure pathways during neurosurgery.
ECoG AND STEREO-EEG FOR BCI
This presentation was recorded during the BCI and Neurotech Spring School 2024 and is about the hardware and software requirements that you need when considering an ECoG or stereo-EEG based Brain Computer Interface.
NEUROMODULATION: OPTIMIZING OPEN-/CLOSED-LOOP BRAIN STIMULATION
This presentation covers open-loop neuromodulation, which uses fixed stimulation parameters without real-time adjustments, offering consistent but less flexible treatment. In contrast, closed-loop systems monitor neural signals and adjust stimulation in real time, providing personalized, adaptive therapy that can improve efficacy and reduce side effects.
EPILEPSY RESEARCH: COMBINING MEG, EEG & ECOG
This presentation showcases the convergence of MEG, EEG, and ECoG techniques in epilepsy research. With expertise and precision, Milena Korostenskaja demonstrated the seamless integration of these modalities. Witness firsthand the innovative approach shaping the future of epilepsy research, as Korostenskaja’s lecture sheds light on the synergy between multiple neuroimaging techniques, offering invaluable insights for researchers and clinicians alike.
HIGH-FREQUENCY OSCILLATIONS AND 3D MAPPING
In this presentation, you’ll see the utilization of high-frequency oscillations (HFOs) and three-dimensional mapping techniques in the analysis of grids and stereo EEG data. It highlightes the importance of HFOs as potential biomarkers for epileptic activity and emphasized the benefits of three-dimensional mapping in accurately localizing brain regions involved in epileptogenic activity, aiding in the diagnosis and treatment of epilepsy.
CORTIQ 2.0 - RUNNING FUNCTIONAL MAPPING PROCEDURES IN REAL-TIME WITH ULTRA-HIGH-GAMMA
The talk demonstrates the capability of running functional mapping procedures in real-time using high (ultra)-gamma frequency bands. It showcases how real-time analysis of high-frequency neural activity can provide valuable insights into brain function, enabling more precise and efficient mapping of eloquent cortex areas during neurosurgical procedures and advancing our understanding of neural dynamics in various cognitive processes.
FUNCTIONAL MAPPING WITH ECOG AND CORTICO-CORTICAL EVOKED POTENTIALS
This presentation highlightes the use of electrocorticography (ECoG) and cortico-cortical evoked potentials (CCEPs) for functional mapping of the brain. It discusses how these techniques provide insights into the functional connectivity and organization of neural networks, aiding in the localization of eloquent cortex areas for neurosurgical planning and understanding brain function in both clinical and research settings.
FACEPHENES AND RAINBOWS
In this study, we observed brain activity as a patient looked at various objects. When we stimulated certain areas, the patient saw faces or colors, regardless of the actual object. These findings highlight how specific brain regions handle different tasks, potentially leading to safer, more precise brain surgeries.
CORTIQ CORTICAL MAPPING SERVICE
g.tec offers scientific services for cortiQ including mappings in your hospital in the USA, Europe and Japan and our scientific team can analyse the data for you. Furthermore, we can adapt the cortiQ paradigms for your mapping needs.
FREQUENTLY ASKED QUESTIONS
Yes. cortiQ 2.0 can stimulate the brain if necessary, providing a complete mapping solution.
- Wernicke’s area (Receptive language)
- Broca’s area (Expressive language)
- Auditory cortex
- Visual cortex
- Somatosensory system
- Motor cortex
- Face recognition
- Color system
- Memory function
Yes. Here is a list of all import publications:
Kanaya, K., Mitsuhashi, T., Kiuchi, T. and Kobayashi, S., 2021. The Efficacy of Intraoperative Passive Language Mapping for Glioma Surgery: A Case Report. Frontiers in neurology, p.1339.
Sanada, T., Kapeller, C., Jordan, M., Grünwald, J., Mitsuhashi, T., Ogawa, H., Anei, R. and Guger, C., 2021. Multi-modal mapping of the face selective ventral temporal cortex–a group study with clinical implications for ECS, ECoG, and fMRI. Frontiers in Human Neuroscience, 15.
Jiang, T., Pellizzer, G., Asman, P., Bastos, D., Bhavsar, S., Tummala, S., … & Ince, N. F. (2020). Power Modulations of ECoG Alpha/Beta and Gamma Bands Correlate With Time-Derivative of Force During Hand Grasp. Frontiers in Neuroscience, 14.
Crowther, L. J., Brunner, P., Kapeller, C., Guger, C., Kamada, K., Bunch, M. E., … & Schalk, G. (2019). A quantitative method for evaluating cortical responses to electrical stimulation. Journal of neuroscience methods311, 67-75.
Ritaccio AL, Brunner P, Schalk G. Electrical Stimulation Mapping of the Brain: Basic Principles and Emerging Alternatives. Journal of clinical neurophysiology: official publication of the American Electroencephalographic Society. 2018 Mar;35(2):86-97.
Swift, J.R., Coon, W.G., Guger, C., Brunner, P., Bunch, M., Lynch, T., Frawley, B., Ritaccio, A.L. and Schalk, G., 2018. Passive Functional Mapping of Receptive Language Areas Using Electrocorticographic Signals. Clinical Neurophysiology.
Kapeller, C., Ogawa, H., Schalk, G., Kunii, N., Coon, W.G., Scharinger, J., Guger, C. and Kamada, K., 2018. Real-Time Detection and Discrimination of Visual Perception Using Electrocorticographic Signals. Journal of Neural Engineering, 15(3), 036001.
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.
Yes, absolutely. In the first surgery, ECoG electrodes will be implanted, but the functional real-time mappings are performed in the Epilepsy Monitoring Unit. This allows neurosurgeons to modify test paradigms based on individual surgical needs. These tests can be performed repeatedly over a longer period of time. This gives the neurosurgeon more time to plan and optimize the surgical resection better with more detailed information and less preparatory work. cortiQ can greatly reduce the risk of artificial seizures during surgery and cannot produce pain for the patient. It’s less consuming and the risk of damage during surgery can be avoided.
Yes, cortiQ can be used for intraoperative monitoring of the brain. It allows real-time brain mappings in the operating room to identify functional brain regions with high-gamma activity before surgical resection. For example, if pathological tissue is close to the motor area, cortiQ will ask the patient to move arms, feet or even lips. The brain activity patterns produced during these movements will be transmitted in real-time to cortiQ, notifying the neurosurgeon what parts are important for a certain movement and therefore should remain untouched.
A mapping that highlights four activation maps usually lasts about 6 min.
Yes, cortiQ comes with a passive listening paradigm that maps the auditory cortex, including the receptive language area, and it can play back language related paradigms like picture naming tasks and map expressive language related cortical regions.
Support surgeons’ planning for brain surgeries by providing additional information about functional brain regions.
The activated neural network is highlighted based on natural behaviors, such as speech or movement. The ECS can only investigate symptoms caused by local dysfunction due to electrical stimulation.
The mapping procedure works with electrode grids and stereo-EEG recordings with depth electrodes.
cortiQ stores the recorded EEG synchronized with the mapping paradigm and provides an importer for MATLAB (The MathWorks Inc., USA). cortiQ mapping results are stored in CSV format for further comparison.
The supervisor can immediately check the quality of the mapping session and stop/change the paradigm at any time. No further offline processing is necessary.
The power of the high-gamma frequency band (60-170Hz) derived from electrocorticographic (ECoG) signals.
The system compares high-gamma activity in the ECoG during resting and active conditions. Changes in the power of the high-gamma band indicate activated neurons with respect to the electrode position. A group of highlighted electrode groups shows an activated neural network. The system updates the activation map in real-time.
This allows the user to interpret the activation during the experiment and to stop the paradigm anytime. The longer the paradigm lasts, the more noise is eliminated, and hence only task-related electrodes are highlighted. A recommended setup contains around 45s active and 45s resting state per task.
Neurosurgeons who want to get additional information about the eloquent cortex and other specific regions, and research groups who want to investigate functional regions of the cortex. Neurosurgeons also benefit from cortiQ’s ability to provide maps in real-time instead of hours or days. Patients benefit from reductions in the time needed for mapping, need for additional mapping procedures, chance of accidental seizures resulting from ECS, and the risk of accidental removal of too little or too much brain tissue.
Unlike ECS, cortiQ does not produce artificial seizures. CortiQ cannot produce dural pain caused by bad electrode contacts. CortiQ shows the neural areas involved in a given task and allows very fast pre-screening that may be used for planning ECS mapping and surgical removal of affected tissue.
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