Periodic Reporting for period 1 - CEREBRO (an electric Contrast medium for computationally intensive Electroencephalographies for high REsolution BRain imaging withOut skull trepanation)
Berichtszeitraum: 2022-09-01 bis 2023-08-31
Imaging the brain activity is fundamentally important for many brain-related scientific disciplines. Among the non-invasive neuroimaging strategies, Electroencephalography (EEG) from scalp potentials is one of the primary. In EEG the neuroninduced electric potential is measured by using electrodes on the patient’s scalp. The skull however, highly resistive, shields EEG recordings limiting the spatial resolution. The standard way to avoid skull shielding effects is to invasively implant EEG electrodes under the skull (ECoG) or in the brain cortex (StereoEEG), in both cases after trepanning the patient’s skull. Scalp EEGs are noninvasive but lack spatial imaging accuracy. ECoG and StereoEEG are highly accurate but require skull trepanation and they image only a limited part of the brain. There is the need for increasing the resolution of scalp EEG providing the same level of accuracy of invasive EEGs. This will be the grand challenge which CEREBRO will achieve by conceiving the first ever existing EEG contrast medium, able to provide imaging of the entire brain and in a non-invasive way.
During this first period, we have performed the following work.
WP1: The preliminary analysis of the physical setting and an advanced design platform allowing for circuit/physical medium design has been achieved. This allowed the completion of the analysis of the main configurations for the medium as foreseen by the project. Three possible designs have been identified and their first incarnations have been full analyzed.
WP2: Significant progress has been achieved towards the completion of the Objective 2: the core underlying technology for brain imaging in the presence of a contrast medium technology is well under way. In particular, we have been capable of deriving a new Calderón-type forward solver that remains accurate and fast (well-conditioned and free from catastrophic loss of accuracies) for the whole frequency band that is being explored as part of Task 1.1/1.2 regardless of the resolution and complexity of the head model. This is a significant improvement with regards to the state of the art, since such a broadband formulation did not exist. Furthermore, given that solutions of the inverse problem, demand numerous solutions of the forward solvers, we have been investigating the possibility of obtaining a fast direct solver, which are orders of magnitude faster for these kinds of scenarii, for the new method. Early results in this investigation have been obtained for static Calderón solvers but warrant further work for the broadband extension.
WP3: The achievement of this objective is running on track. The fast prototyping platform is under design and we expect to be delivered on time by month 18th. Moreover we have started analysing the different reading configurations that will be adapted to each medium type that will be implemented and built.
WP4: Experimental validation.
The achievement of this objective is running on track. To prepare for the final validation of CEREBRO’s technology, fabrication of brain phantoms has started. In this first phase we have managed to produce a first generation of brain phantoms. This first generation is capable of reproducing the electric properties of the head at the lower end of the frequency spectrum.
WP1: The preliminary analysis of the physical setting and an advanced design platform allowing for circuit/physical medium design has been achieved. This allowed the completion of the analysis of the main configurations for the medium as foreseen by the project. Three possible designs have been identified and their first incarnations have been full analyzed.
WP2: Significant progress has been achieved towards the completion of the Objective 2: the core underlying technology for brain imaging in the presence of a contrast medium technology is well under way. In particular, we have been capable of deriving a new Calderón-type forward solver that remains accurate and fast (well-conditioned and free from catastrophic loss of accuracies) for the whole frequency band that is being explored as part of Task 1.1/1.2 regardless of the resolution and complexity of the head model. This is a significant improvement with regards to the state of the art, since such a broadband formulation did not exist. Furthermore, given that solutions of the inverse problem, demand numerous solutions of the forward solvers, we have been investigating the possibility of obtaining a fast direct solver, which are orders of magnitude faster for these kinds of scenarii, for the new method. Early results in this investigation have been obtained for static Calderón solvers but warrant further work for the broadband extension.
WP3: The achievement of this objective is running on track. The fast prototyping platform is under design and we expect to be delivered on time by month 18th. Moreover we have started analysing the different reading configurations that will be adapted to each medium type that will be implemented and built.
WP4: Experimental validation.
The achievement of this objective is running on track. To prepare for the final validation of CEREBRO’s technology, fabrication of brain phantoms has started. In this first phase we have managed to produce a first generation of brain phantoms. This first generation is capable of reproducing the electric properties of the head at the lower end of the frequency spectrum.
In this first year of work we have obtained already several advancements with respect to the state of the art, in particular:
1) We have obtained the first brain modeller, based on new Calderón-type forward solvers that remains accurate and fast (well-conditioned and free from catastrophic loss of accuracies) for the whole frequency band of interest, regardless of the resolution and complexity of the head model. The new approach is expected to impact sensibly this project and beyond and its exploitation are under investigation.
2) A fast prototyping platform has been designed and we expect to be delivered on time to sensibly impact this project and beyond.
3) We have completed the first design phase of the medium, fabrication phase is now starting.
1) We have obtained the first brain modeller, based on new Calderón-type forward solvers that remains accurate and fast (well-conditioned and free from catastrophic loss of accuracies) for the whole frequency band of interest, regardless of the resolution and complexity of the head model. The new approach is expected to impact sensibly this project and beyond and its exploitation are under investigation.
2) A fast prototyping platform has been designed and we expect to be delivered on time to sensibly impact this project and beyond.
3) We have completed the first design phase of the medium, fabrication phase is now starting.