# US 8,543,199 B2 · Implantable systems and methods for identifying a contra-ictal condition in a subject > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,543,199 B2 - Document ID: US8543199B2 - Status: Granted - Kind: B2 - Application number: 13/225,241 - Filed: 2011-09-02 - Published: 2011-12-29 - Granted: 2013-09-24 - Earliest claimed: 2007-03-21 - Assignees: Cyberonics, Inc. - Applicants: David Snyder; Kent W. Leyde; John F. Harris - Inventors: David Snyder; Kent W. Leyde; John F. Harris - Web page: https://patentgrep.com/patent/US8543199B2 ## CPC - A61B 5/02055: {Simultaneously evaluating both cardiovascular condition and temperature} - A61B 5/0006: {ECG or EEG signals} - A61B 5/0031: {Implanted circuitry} - A61B 5/01: Measuring temperature of body parts {; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue} (clinical contact thermometers G01K13/20) - A61B 5/0205: Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition - A61B 5/021: Measuring pressure in heart or blood vessels - A61B 5/026: Measuring blood flow {(A61B3/1233, A61B3/1241 take precedence)} - A61B 5/08: Measuring devices for evaluating the respiratory organs - A61B 5/145: Measuring characteristics of blood in vivo, e.g. gas concentration or pH-value {; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid or cerebral tissue} (non-radiation detecting or locating of foreign bodies in blood A61B5/06) - A61B 5/14552: {Details of sensors specially adapted therefor} - A61B 5/349: Detecting specific parameters of the electrocardiograph cycle - A61B 5/374: Detecting the frequency distribution of signals, e.g. detecting delta, theta, alpha, beta or gamma waves - A61B 5/4094: {Diagnosing or monitoring seizure diseases, e.g. epilepsy} - A61B 5/7232: {involving compression of the physiological signal, e.g. to extend the signal recording period} - A61B 2560/0219: of externally powered implanted units - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract Systems and methods of monitoring a subject's neurological condition are provided. In some embodiments, the method includes the steps of analyzing a physiological signal (such as an EEG) from a subject to determine if the subject is in a contra-ictal condition; and if the subject is in a contra-ictal condition, providing an indication (e.g., to the subject and/or to a caregiver) that the subject is in the contra-ictal condition. The systems and methods may utilize a minimally invasive, leadless device to monitor the subject's condition. In some embodiments, if the subject is in a pro-ictal condition, the method includes the step of providing an indication (such as a red light) that the subject is in the pro-ictal condition. ## Claims ### Claim 1 A neurological monitoring system comprising: an implantable device; and an external transmission assembly configured to deliver power to the implantable device and to receive a wireless data signal from the implantable device, the implantable device comprising a processing assembly for sampling a neurological signal from a subject, a power assembly for receiving power from the external transmission assembly, and a communication assembly for transmitting the wireless data signal from within a subject's body to the external transmission assembly, said wireless data signal being encoded with data indicative of the sampled neurological signal, the processing assembly being configured to process the wireless data signal from the implantable device to determine if the subject is in a contra-ictal condition, said contra-ictal condition being a neurological state in which the subject is unlikely to transition into an ictal condition within a time period. ### Claim 2 (depends on 1) The neurological monitoring system of claim 1, further comprising a user interface configured to provide an output to the subject that indicates that the subject is in the contra-ictal condition. ### Claim 3 (depends on 2) The neurological monitoring system of claim 2, further comprising a subject advisory device comprising the external transmission assembly, the processing assembly, and the user interface. ### Claim 4 (depends on 3) The neurological monitoring system of claim 3, wherein the subject advisory device comprises a memory for storing the data indicative of the sampled neurological signal. ### Claim 5 (depends on 1) The neurological monitoring system of claim 1, wherein the external transmission assembly is configured to deliver power to the implantable device via electromagnetic induction. ### Claim 6 (depends on 5) The neurological monitoring system of claim 5, wherein the external transmission assembly is configured to receive the wireless data signal from the implantable device via electromagnetic induction. ### Claim 7 (depends on 5) The neurological monitoring system of claim 5, wherein the external transmission assembly is configured to receive the wireless data signal from the implantable device via an RF link. ### Claim 8 (depends on 1) The neurological monitoring system of claim 1, wherein the external transmission assembly is configured to receive the wireless data signal from the implantable device via an RF link. ### Claim 9 (depends on 1) The neurological monitoring system of claim 1, wherein the external transmission assembly is configured to simultaneously deliver power to the implantable device and receive the wireless data signal from the implantable device. ### Claim 10 (depends on 1) The neurological monitoring system of claim 1, wherein the wireless data signal includes a heart rate signal. ### Claim 11 (depends on 1) The neurological monitoring system of claim 1, wherein the wireless data signal includes a respiratory signal. ### Claim 12 (depends on 1) The neurological monitoring system of claim 1, wherein the wireless data signal corresponds to at least one of a blood pressure, a blood oxygenation, a temperature, a blood flow, an ECG, an EKG, a chemical concentration of a neurotransmitter, a chemical concentration of a medication, and a pH in the blood. ### Claim 13 (depends on 1) The neurological monitoring system of claim 1, wherein the processing assembly is adapted to determine if the subject is in a contra-ictal condition by: extracting N features from the sampled neurological signal; generating a N-dimensional feature vector of the extracted N features for time points of the sampled neurological signal; and determining if the N-dimensional feature vector is within a contra-ictal cluster or region in the N-dimensional space. ### Claim 14 (depends on 1) The neurological monitoring system of claim 1, wherein the neurological signal is an EEG signal. ### Claim 15 A method of monitoring neurological signals from a subject, said method comprising: delivering power from an external transmission assembly to an implanted device; sampling a neurological signal from the subject with the implanted device; transmitting a wireless data signal from within the subject's body to the external transmission assembly, said wireless data signal being encoded with data indicative of the sampled neurological signal; and analyzing the neurological signal from the subject using a processor to determine if the subject is in a contra-ictal condition, said contra-ictal condition being a neurological state in which the subject is unlikely to transition into an ictal condition within a time period. ### Claim 16 (depends on 15) The method of claim 15, wherein the wireless data signal includes a respiratory signal. ### Claim 17 (depends on 15) The method of claim 15, wherein the wireless data signal corresponds to at least one of a blood pressure, a blood oxygenation, a temperature, a blood flow, an ECG, an EKG, a chemical concentration of a neurotransmitter, a chemical concentration of a medication, and a pH in the blood. ### Claim 18 (depends on 15) The method of claim 15, wherein the wireless data signal includes a heart rate signal. ### Claim 19 (depends on 15) The method of claim 15, wherein said delivering power from the external transmission assembly to the implanted device comprises delivering power from the external transmission assembly to the implanted device via electromagnetic induction. ### Claim 20 (depends on 19) The method of claim 19, wherein said transmitting the wireless data signal from within the subject's body to the external transmission assembly comprises transmitting the wireless data signal from within the subject's body to the external transmission assembly via electromagnetic induction. ### Claim 21 (depends on 19) The method of claim 19, wherein said transmitting the wireless data signal from within the subject's body to the external transmission assembly comprises transmitting the wireless data signal from within the subject's body to the external transmission assembly via an RF link. ### Claim 22 (depends on 15) The method of claim 15, wherein said transmitting the wireless data signal from within the subject's body to the external transmission assembly comprises transmitting the wireless data signal from within the subject's body to the external transmission assembly via an RF link. ### Claim 23 (depends on 15) The method of claim 15, wherein said delivering power from the external transmission assembly is performed at the same time as said transmitting the wireless data signal. ### Claim 24 (depends on 15) The method of claim 15, wherein the analyzing the neurological signal comprises: extracting N features from the sampled neurological signal; generating a N-dimensional feature vector of the extracted N features for time points of the sampled neurological signal; and determining if the N-dimensional feature vector is within a contra-ictal cluster or region in the N-dimensional space. ### Claim 25 (depends on 15) The method of claim 15, wherein the neurological signal is an EEG signal. ### Claim 26 A neurological monitoring system comprising: an implantable device; an external transmission assembly configured to receive a wireless data signal from the implantable device; and a processing assembly for sampling a signal from a subject, wherein the implantable device includes a power assembly for receiving power from the external transmission assembly and a communication assembly for transmitting the wireless data signal from within a subject's body to the external transmission assembly, said wireless data signal being encoded with data indicative of the sampled signal, and wherein the processing assembly is configured to process the wireless data signal from the implantable device to determine if the subject is in a contra-ictal condition, said contra-ictal condition being a neurological state in which the subject is unlikely to transition into an ictal condition within a time period. ### Claim 27 (depends on 26) The neurological monitoring system of claim 26, wherein the wireless data signal includes a heart rate signal. ### Claim 28 (depends on 26) The neurological monitoring system of claim 26, wherein the wireless data signal includes a respiratory signal. ### Claim 29 (depends on 26) The neurological monitoring system of claim 26, wherein the wireless data signal corresponds to at least one of a blood pressure, a blood oxygenation, a temperature, a blood flow, an ECG, an EKG, a chemical concentration of a neurotransmitter, a chemical concentration of a medication, and a pH in the blood. ### Claim 30 A method of monitoring signals from a subject, said method comprising: delivering power to an implanted device; sampling a signal from the subject with the implanted device; transmitting a wireless data signal from within the subject's body to an external transmission assembly, said wireless data signal being encoded with data indicative of the sampled signal; and analyzing the sampled signal from the subject using a processor to determine if the subject is in a contra-ictal condition, said contra-ictal condition being a neurological state in which the subject is unlikely to transition into an ictal condition within a time period. ### Claim 31 (depends on 30) The method of claim 30, wherein the wireless data signal includes a heart rate signal. ### Claim 32 (depends on 30) The method of claim 30, wherein the wireless data signal includes a respiratory signal. ### Claim 33 (depends on 30) The method of claim 30, wherein the wireless data signal corresponds to at least one of a blood pressure, a blood oxygenation, a temperature, a blood flow, an ECG, an EKG, a chemical concentration of a neurotransmitter, a chemical concentration of a medication, and a pH in the blood.