SBIR-STTR Award

The long-term objective of the proposed project is to design a low-profile, high-resistive, MRI-compatible dense array EEG sensor net for simultaneous dEEG/fMRI recordings in fields as high as 7 Tesla. This novel sensor net (256-channel InkNet) will use innovative conductive ink leads printed on polymer thick film (PTF) developed at the Analog Brain Imaging Laboratory (ABILAB) at the A. A. Martinos Center of Massachusetts General Hospital. The InkNet will interface with dEEG MRI-compatible hardware and software recently developed at Electrical Geodesics Inc. (EGI). This proposed system will provide safe, noninvasive, and affordable dEEG/fMRI technology to both clinicians and researchers, thereby enabling routine multimodal imaging of human brain function with unprecedented spatiotemporal resolution. Application of this technology will enhance the understanding of healthy brain function, treatment of many neural pathologies, {and pre-surgical planning}. For Phase I, the first Specific Aim is to modify EEG electrodes for MR-compatible dense-array InkNet recordings. The new InkNet will take advantage of EGI's patented low-profile 256-channel geodesic sensor net (HCGSN) structure. Two electrode designs will be developed and tested. The first will miniaturize the existing 32-channel InkCap half-ring electrodes to fit the HCGSN structure by embedding the electrode directly into the harness design rather than using an adhesive. The alternative design will interface EGI's pellet electrode to PTF ink leads by gluing it to an interface pad printed with polyimide conductive glue. Both designs will be tested using two abrasion-free skin applications: EGI's current electrolyte-soaked sponges and a novel biopotential hydrogel. Performance tests for high signal-to-noise ratio (SNR) and low drift will determine the best electrode design for the Phase I prototype. The Second Specific Aim is to design new PTF traces for efficient routing of the 256 electrode leads. An autorouter program (SPECCTRA) will test nine router parameters to converge on the optimal trace width and length which will then used to determine the number vias and layers required. A fixed trace width of 5 mils to ensure manufacturability will be achieved by testing for spacing violations during the SPECCTRA routing iterations. The final prototype circuits will be printed using a custom mix of carbon and silver inks tested for optimal dielectric and conductive properties. The Third Specific Aim is to test the new dEEG/fMRI system for safety and data integrity. Safety tests will be performed using finite difference time domain (FDTD) numerical simulations with an anatomically accurate head model, followed by actual temperature measurements in the 7T scanner using a specially developed phantom (CHEMA), high-power TSE imaging sequences to induce RF heating, and a four-channel Fluoroptic Thermometer. After confirming safety, MRI and EEG data integrity will be tested at 3T and 7T field strengths using T1-weighted structural sequence, a resting EEG alpha protocol, and a visual processing study. Analyses will contrast MRI quality with and without the InkNet, and EEG quality within and outside the MR scanner.

Public Health Relevance:
The goal of this project is to develop a system for simultaneous measurement of brain activity using two complementary methods: electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). This state-of-the-art system will offer brain scientists and clinicians a safe, non-invasive tool for studying human brain function with unprecedented spatial and temporal precision. This knowledge will help us better understand healthy brain function, treat many disorders (e.g., epilepsy), and improve pre-surgical planning.

Thesaurus Terms:
"21+ Years Old; Adhesives; Adult; Ag Element; Area; Artifacts; Arts; Brain; Brain Imaging; C Element; Carbon; Cell Communication And Signaling; Cell Signaling; Clinical Research; Clinical Study; Complex; Computer Programs; Computer Software; Custom; Development; Disease; Disorder; Dysfunction; Eeg; Electrodes; Electroencephalography; Electrolytes; Electromagnetic; Electromagnetics; Encephalon; Encephalons; Ensure; Environment; Epilepsy; Epileptic Seizures; Epileptics; Film; Functional Magnetic Resonance Imaging; Functional Disorder; Gel; General Hospitals; Glues; Goals; Head; Heating; Human; Human, Adult; Human, General; Hydrogels; Image; Imaging Technology; Infant; Inferior; Ink; Intracellular Communication And Signaling; Investigators; Knowledge; Laboratories; Leadership; Legal Patent; Length; Liquid Substance; Mr Imaging; Mr Tomography; Mri; Mri Scans; Mri, Functional; Magnetic Resonance Imaging; Magnetic Resonance Imaging Scan; Magnetic Resonance Imaging, Functional; Magnetism; Man (Taxonomy); Man, Modern; Marketing; Massachusetts; Measurement; Measures; Medical; Medical Imaging, Magnetic Resonance / Nuclear Magnetic Resonance; Metals; Methods; Methods And Techniques; Methods, Other; Modeling; Morphologic Artifacts; Multimodal Imaging; Multimodality; Nmr Imaging; Nmr Tomography; Nervous; Nervous System, Brain; Neurosciences; Noise; Nuclear Magnetic Resonance Imaging; Operation; Operative Procedures; Operative Surgical Procedures; Outcome; Patents; Pathology; Phase; Physiopathology; Polymers; Porifera; Printing; Production; Programs (Pt); Programs [publication Type]; Property; Property, Loinc Axis 2; Protocol; Protocols Documentation; Psychopathology; Publishing; Research Personnel; Researchers; Resolution; Rest; Route; Safety; Sampling; Scalp; Scalp Structure; Scientist; Seizure Disorder; Signal Transduction; Signal Transduction Systems; Signaling; Silver; Skin; Software; Source; Sponges; Sponges (Zoology); Structure; Surface; Surgical; Surgical Interventions; Surgical Procedure; System; System, Loinc Axis 4; Techniques; Technology; Temperature; Testing; Thermometers; Thick; Thickness; Time; Trauma, Brain; Traumatic Brain Injury; Traumatic Encephalopathy; Weight; Width; Work; Zeugmatography; Abnormal Psychology; Adult Human (21+); Analog; Base; Biological Signal Transduction; Brain Visualization; Computer Program/Software; Cost; Data Integrity; Density; Design; Designing; Disease/Disorder; Epilepsia; Epileptiform; Epileptogenic; Fmri; Fluid; Human Subject; Imaging; Imaging Modality; Improved; Innovate; Innovation; Innovative; Liquid; Magnetic; Magnetic Field; Miniaturize; Neural; Neuroimaging; Novel; Pathophysiology; Performance Tests; Programs; Prototype; Public Health Relevance; Relating To Nervous System; Safety Testing; Sensor; Simulation; Spatiotemporal; Surgery; Tool; Traumatic Brain Damage; Usability; Visual Process; Visual Processing"

The long-term objective of the proposed project is to design a low-profile, high-resistive, MRI-compatible dense array EEG sensor net for simultaneous dEEG/fMRI recordings in fields as high as 7 Tesla. This novel sensor net (256-channel InkNet) will use innovative conductive ink leads printed on polymer thick film (PTF) developed at the Analog Brain Imaging Laboratory (ABILAB) at the A. A. Martinos Center of Massachusetts General Hospital. The InkNet will interface with dEEG MRI-compatible hardware and software recently developed at Electrical Geodesics Inc. (EGI). This proposed system will provide safe, noninvasive, and affordable dEEG/fMRI technology to both clinicians and researchers, thereby enabling routine multimodal imaging of human brain function with unprecedented spatiotemporal resolution. Application of this technology will enhance the understanding of healthy brain function, treatment of many neural pathologies, {and pre-surgical planning}. For Phase I, the first Specific Aim is to modify EEG electrodes for MR-compatible dense-array InkNet recordings. The new InkNet will take advantage of EGI's patented low-profile 256-channel geodesic sensor net (HCGSN) structure. Two electrode designs will be developed and tested. The first will miniaturize the existing 32-channel InkCap half-ring electrodes to fit the HCGSN structure by embedding the electrode directly into the harness design rather than using an adhesive. The alternative design will interface EGI's pellet electrode to PTF ink leads by gluing it to an interface pad printed with polyimide conductive glue. Both designs will be tested using two abrasion-free skin applications: EGI's current electrolyte-soaked sponges and a novel biopotential hydrogel. Performance tests for high signal-to-noise ratio (SNR) and low drift will determine the best electrode design for the Phase I prototype. The Second Specific Aim is to design new PTF traces for efficient routing of the 256 electrode leads. An autorouter program (SPECCTRA) will test nine router parameters to converge on the optimal trace width and length which will then used to determine the number vias and layers required. A fixed trace width of 5 mils to ensure manufacturability will be achieved by testing for spacing violations during the SPECCTRA routing iterations. The final prototype circuits will be printed using a custom mix of carbon and silver inks tested for optimal dielectric and conductive properties. The Third Specific Aim is to test the new dEEG/fMRI system for safety and data integrity. Safety tests will be performed using finite difference time domain (FDTD) numerical simulations with an anatomically accurate head model, followed by actual temperature measurements in the 7T scanner using a specially developed phantom (CHEMA), high-power TSE imaging sequences to induce RF heating, and a four-channel Fluoroptic Thermometer. After confirming safety, MRI and EEG data integrity will be tested at 3T and 7T field strengths using T1-weighted structural sequence, a resting EEG alpha protocol, and a visual processing study. Analyses will contrast MRI quality with and without the InkNet, and EEG quality within and outside the MR scanner.

Public Health Relevance:
The goal of this project is to develop a system for simultaneous measurement of brain activity using two complementary methods: electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). This state-of-the-art system will offer brain scientists and clinicians a safe, non-invasive tool for studying human brain function with unprecedented spatial and temporal precision. This knowledge will help us better understand healthy brain function, treat many disorders (e.g., epilepsy), and improve pre-surgical planning.

Public Health Relevance Statement:
Project Narrative The goal of this project is to develop a system for simultaneous measurement of brain activity using two complementary methods: electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). This state-of-the-art system will offer brain scientists and clinicians a safe, non-invasive tool for studying human brain function with unprecedented spatial and temporal precision. This knowledge will help us better understand healthy brain function, treat many disorders (e.g., epilepsy), and improve pre-surgical planning.

NIH Spending Category:
Bioengineering; Brain Disorders; Clinical Research; Diagnostic Radiology; Epilepsy; Neurodegenerative; Neurosciences

Project Terms:
Adhesives; Adult; analog; Area; base; Brain; Brain imaging; Carbon; Clinical Research; Complex; Computer software; cost; Custom; data integrity; density; design; Development; Disease; Electrodes; Electroencephalography; Electrolytes; Electromagnetics; Ensure; Environment; Epilepsy; Film; Functional disorder; Functional Magnetic Resonance Imaging; Gel; General Hospitals; Glues; Goals; Head; Heating; Human; human subject; Hydrogels; Image; imaging modality; Imaging technology; improved; Infant; Inferior; Ink; innovation; Knowledge; Laboratories; Leadership; Legal patent; Length; Liquid substance; magnetic field; Magnetic Resonance Imaging; Magnetism; Marketing; Massachusetts; Measurement; Measures; Medical; Metals; Methods; miniaturize; Modeling; Morphologic artifacts; MRI Scans; Multimodal Imaging; neuroimaging; Neurosciences; Noise; novel; Operative Surgical Procedures; Outcome; Pathology; performance tests; Phase; Polymers; Porifera; Printing; Production; programs; Property; Protocols documentation; prototype; Psychopathology; public health relevance; Publishing; relating to nervous system; Research Personnel; Resolution; Rest; Route; Safety; safety testing; Sampling; Scalp structure; Scientist; sensor; Signal Transduction; Silver; simulation; Skin; Source; spatiotemporal; Structure; Surface; System; Techniques; Technology; Temperature; Testing; Thermometers; Thick; Time; tool; Traumatic Brain Injury; usability; visual process; visual processing; Weight; Width; Work