Patent Application
20240156345
Nearly 800,000 strokes occur in the U.S. annually, and almost 3 million Americans are currently disabled from them. Stroke is the third leading cause of death in the U.S. and is the leading cause of disability costing over $73 billion/year in the U.S. alone.
The most disabling and deadly ischemic strokes (i.e., lack of blood flow to the brain) result from large vessel occlusions (“LVO”). Patients with LVO's have extremely poor outcomes without treatment. Developments over the years have shown that LVO's in brain vessels can be extracted using devices and catheters inserted through the groin artery. Studies, during this same timeframe, showed a positive benefit of endovascular therapy (“EVT”) over prior medical management of LVO's, and several of these studies showed that earlier intervention produced better clinical outcomes.
In one study, patients transferred to a hospital without EVT capability had an average delay of two hours before arriving to the final EVT-capable facility. This is an unacceptable delay when time is critical to preserving brain function. The emerging dilemma lies in accurate field stroke triage. Only a portion of ischemic strokes result from LVO's, and EVT does not benefit the rest. Movement of both LVO and non-LVO stroke patients to a single EVT-capable center might delay or deprive a patient of standard of care treatment for non-LVO strokes. It might also overwhelm an EVT-capable hospital.
Imaging identification of LVO's exists with MRI and CT, but these methods, due to the size of the equipment involved and the calculations being made, typically require a trained operator in a hospital environment and are not suitable for use in a field environment. Attempts to create portable, field useable devices that detect LVO's are still not ideal. These devices, typically, are fairly complex and measure cerebral oximetry; requiring substantial calculation power and hardware to perform intricate calculations. Further, cerebral oximetry alone is known to be a highly inaccurate estimator of true oxygen saturation of the brain because of differences in patient skin color, skull thickness, among other things. Its main utilization is to trend a specific person's cerebral oximetry values. In other words, the patient's cerebral oximetry value, at one time (preferably during the normal state), is used as a basis of longitudinal comparison when said patient is anticipated to be placed under physiological stress, such as prolonged cardiac arrest, cardiac surgery and cardiopulmonary bypass, or significant brain injury. Also, the sensors on an LVO detection device need to be placed in specific spots on the head to get proper readings. These other devices, to get them placed in the correct spot on the patient, require a highly trained operator who is trained in the proper placement of the LVO detection device. It is not feasible to have enough highly trained operators like this in the field, ready to respond to every emergency situation involving an LVO. These other LVO detection devices also, typically, take measurements for LVO's in areas of the brain which are not ideal, and often unreliable, for detecting an LVO.
Other devices measure cerebral oxygen, cerebral blood flow or cerebral oxygen saturation dynamically over time, such as over a cardiac cycle or any physiological time period. These devices first measure the amount of near-infrared and infrared light reflection, which are unique aspects of deoxyhemoglobin and oxyhemoglobin.
Oxyhemoglobin and deoxyhemoglobin reflect light at different wavelengths. Different wavelength reflections are used to calculate the concentrations of both of these blood cell products. In these conventional cerebral oximetry devices, the signal from the photodiode is used to calculate oxyhemoglobin and deoxyhemoglobin concentrations. These values are then input into known physiological formulas to calculate the cerebral oxygen saturation level and cerebral blood flow within the tissue. Sometimes, these other devices implement a large band of sensors on both sides of the head to make their measurements, which can make readings unreliable since they are measuring through hair at some points, and they also sometimes use a compression mechanism to conduct a coherence test. These features of the other devices make them undesirable or inadequate for LVO detection in the field in an emergency situation because the features of these other devices create significant detection variability; often result in the sensors being placed in the incorrect position; often provide data that is unreliable or of little value in the field; require the device to be a bulky and fragile device and rely on complicated calculations and formulas to make an LVO assessment.
Accordingly, there is a need to diagnose LVOs quickly and provide appropriate medical intervention. The ideal adjunct to the EMT or paramedic assessing a possible stroke patient is a field-expedient, operator-independent device to help determine whether a patient, potentially needs EVT. Such a device could effectively diagnose while minimizing diagnostic error and operator training. Such a device could also help emergency doctors at non-EVT hospitals identify EVT-eligible patients earlier and expedite transfer to EVT-capable hospitals without doing additional time-consuming imaging.
According to one aspect of the present invention, a portable head-mounted diagnostic device for diagnosing conditions consistent with the existence of a blockage of a blood vessel in the brain of a patient, such as a large vessel occlusion, may include a control assembly storing a threshold value; a pair of signal generation devices; a pair of reflected signal sensors; where the pair of signal generator devices each has the capability to transmit a signal into the brain of the patient, creating a reflected signal, and one of the pair of signal generation devices transmits a signal into the left side of the brain of the patient and the other of the pair of signal generation devices transmits a signal into the right side of the brain of the patient; where the pair of reflected signal sensors each has the capability to receive the created reflected signals and one of the pair of reflected signal sensors receives the reflected signal on the left side of the brain of the patient, and the other of the pair of reflected signal sensors receives the reflected signal on the right side of the brain of the patient; where the reflected signal sensors convert the received signals into a single data point amplitude value for each of the left side and right side of the brain; and where the control assembly calculates the difference between the single data point amplitude value for the left side of the brain and the single data point amplitude value for the right side of the brain and compares the calculated difference to the threshold value to determine if a large vessel occlusion condition exists.
According to another aspect of the present invention, a portable head-mounted diagnostic device for diagnosing conditions consistent with the existence of a blockage of a blood vessel in the brain of a patient, such as a large vessel occlusion, includes a control assembly storing a threshold value; a sensor support structure having a pair of signal generation devices, a pair of shallow reflected signal sensors; and a pair of deep reflected signal sensors; and a head engagement assembly having a temple arm structure and a connected pair of nose supports. The pair of signal generator devices each has the capability to transmit a signal into the brain of the patient, creating a shallow reflected signal and a deep reflected signal, and one of the pair of signal generation devices transmits a signal into the left side of the brain of the patient and the other of the pair of signal generation devices transmits a signal into the right side of the brain of the patient. The pair of shallow reflected signal sensors each has the capability to receive the created shallow reflected signals and one of the pair of shallow reflected signal sensors receives the shallow reflected signal on the left side of the brain of the patient, and the other of the pair of shallow reflected signal sensors receives the shallow reflected signal on the right side of the brain of the patient. Further, the pair of deep reflected signal sensors each has the capability to receive the created deep reflected signals and one of the pair of deep reflected signal sensors receives the deep reflected signal on the left side of the brain of the patient, and the other of the pair of deep reflected signal sensors receives the deep reflected signal on the right side of the brain of the patient.
The shallow reflected signal sensors and the deep reflected signal sensors, in this aspect of the invention, convert the received signals into a single data point amplitude value for each of the left side and right side of the brain. The control assembly calculates the difference between the single data point amplitude value for the left side of the brain and the single data point amplitude value for the right side of the brain for the shallow reflected signal and compares the calculated difference to the threshold value to determine if a large vessel occlusion condition exists; and calculates the difference between the single data point amplitude value for the left side of the brain and the single data point amplitude value for the right side of the brain for the deep reflected signal and compares the calculated difference to the threshold value to determine if a large vessel occlusion condition exists.
According to yet another aspect of the present invention, a method for diagnosing conditions consistent with the existence of a blockage of a blood vessel in the brain of a patient, such as a large vessel occlusion, includes the steps of providing a portable head-mounted diagnostic device having a control assembly storing a threshold value; a pair of signal generation devices and at least a pair of reflected signal sensors; transmitting a signal into the left side of the brain of the patient from one of the pair of signal generator devices, wherein the signal interaction with the blood vessels on the left side of the brain creates a reflected signal; simultaneously transmitting a signal into the right side of the brain of the patient from the other of the pair of signal generator devices, wherein the signal interaction with the blood vessels on the right side of the brain creates a reflected signal; receiving and converting the left side reflected signal into a single data point amplitude value at one of the pair of reflected signal sensors; receiving and converting the right side reflected signal into a single data point amplitude value at the other of the pair of reflected signal sensors; calculating the difference between the single data point amplitude value for the left side of the brain and the single data point amplitude value for the right side of the brain; and comparing the calculated difference to the threshold value to determine if a large vessel occlusion condition exists.
Objects, features, and advantages of the present invention will become apparent upon reading the following description in conjunction with the drawing figures, in which:
Referring to
In this embodiment, the first and third component supports 46, 50 each have signal generation devices 70a, 70b (general reference to a signal generation device is designated as 70) and sensors 71a, 71b (general reference to a sensor is designated as 71 or 73) attached to them. In this embodiment, the signal generation devices 70a, 70b are infrared or near infrared light emitting diodes (“LED's”). It should be understood that in other embodiments of the present invention any number of signal generation devices 70 may be used; that the signal generation devices 70 may operate in any spectrum required and that the signal generation devices 70 may be set at any strength of signal required.
In this embodiment, the second and fourth supports 48, 52 each have sensors 73a, 73b attached to them. In this embodiment, the sensors 71a, 71b, 73a, 73b are photodiodes that receive and convert reflected infrared or near infrared signals generated by the LED's 70a, 70b. It should be understood that in other embodiments of the present invention any number of sensors 71, 73 may be used and that the sensors 71, 73 may receive energy in any spectrum or manner required. In this embodiment, each signal generation device 70a, 70b and sensor 71a, 71b, 73a, 73b is surrounded by a pad 72 attached to the corresponding first component support 46, second component support 48, third component support 50 or fourth component support 52. The pads 72 provide comfort to a patient and acts to help block unwanted ambient light from interfering with the signal generation devices 70a, 70b and the sensors 71a, 71b, 73a, 73b.
Further, the sensor support structure 40 is in power and command communication with the control assembly 22. Embedded on the sensor support structure 40 are a series of wires 82 that are integrated with and run through the sensor support structure 40 and ultimately connect with each signal generation device 70a, 70b and sensor 71a, 71b, 73a, 73b to power and provide command instructions from the control assembly 22 to each signal generation device 70a, 70b and sensor 71a, 71b, 73a, 73b.
In one embodiment, the components 22, 24, 26 of the LVO detector assembly 20 are integrated with one another in an inseparable configuration. In other embodiments, such as depicted in
Referring to
Referring now to
Since it is envisioned that the user may be assembling the components 22, 24, 26 on the spot in a rushed, emergency situation, features have been designed into an embodiment of the LVO detection assembly 20 to make it easier for the user to assemble the LVO detection assembly 20. Specifically, to assemble the LVO detection assembly 20, the user may pick up the sensor support structure 24 and line up the protruding connection piece 92 of the sensor support structure 24 with the top connection slot 96 of the control assembly 22. Once lined up, the user pushes the protruding connection piece 92 into the top connection slot 96. As the sensor support structure 24 is moved towards the control assembly 22, the power and control interface 80 of the sensor support structure 24 engages with, and forms an electrical connection with, the power and control interface 86 of the control assembly 22. In this embodiment, to assist with alignment of the power and control interfaces 80, 86, the embedded magnets 90a, 90b of the sensor support structure 24 attract to, and pair up with, a magnetically attracting portion of the control assembly 22. In addition, the alignment post 100 of the control assembly 22 engages with the alignment slot 94 of the sensor support structure 24. After connecting the sensor support structure 24 to the control assembly 22, the user connects the head engagement assembly 26 to the control assembly 22 by lining up the connection tab 99 of the head engagement assembly 26 with the bottom connection slot 97 of the control assembly 22. Once lined up, the user pushes the connection tab 99 into the bottom connection slot 97. The LVO detector assembly 20 is now assembled and ready for use. It should be understood that the order in which the components 22, 24, 26 of the LVO detector assembly 20 are connected to one another is not important, and the components 22, 24, 26 may be connected to each other in any order.
With an LVO detector assembly 20 retrieved, the user places the LVO detector assembly 20 on the patient's head 114 as depicted in
To help ensure that a user, even of limited experience or minimal training, places the LVO detector assembly 20 in the correct spot on the patient's head 114, the LVO detector assembly 20 of the present invention is designed so that no matter who is placing the LVO detector assembly 20 on the patient's head 114, the LVO detector assembly 20 will be put in the right place due to the relative invariability, no matter the patient 112, between the individual patient's relationship between the patient's nasal bridge 120, the root helices 122a, 122b of the ears 124a, 124b; the temples 116a, 166b and the forehead 118. No specialized training is required to place the LVO detector assembly 20 in the proper location, which was not the case with other LVO alert detection systems. Specifically, the user starts to slide the temple ends 31a, 31b over the patient's respective root helices 122a, 122b. As the user continues to slide LVO detection assembly 20 towards the back of the patient's head 114, over the root helices 122a, 122b, the signal generation devices 70a, 70b engage the temples 116a, 116b; the sensors 71a, 71b engage an area of the patient's head 114 between the forehead 118 and adjacent to the signal generation devices 70a, 70b; and the sensors 73a, 73b engage the patient's forehead 118. The hinged connectors 44a, 44b of the secondary support arms 42a, 42b; the hinged connectors 54, 56, 58, 60 of the component supports 46, 48, 50, 52 allow the signal generation devices 70a, 70b and the sensors 71a, 71b, 73a, 73b to move freely, as needed, to allow the LVO detector assembly 20 to form a proper, close fit on the patient's head 114, temples 116a, 116b and forehead 118. At the same time, the nose pads 34a, 34b of the nose support structure 32 engage the nasal bridge 120 of the patient 112. In this way, the LVO detector assembly 20 ensures it can reproducibly be placed on any patient relative to the areas of the forehead 118 and temples 116a, 116b over which the signal generation devices 70a, 70b and the sensors 71a, 71b 73a, 73b need to be placed to develop appropriate data to determine if the patient 112 is suffering from an LVO. In a preferred embodiment, when the LVO detector assembly 20 is in place on the patient's head 114, the signal generation devices 70a, 70b overlie the temples 116a, 116b and directly underneath both of which, at a depth of about 6 centimeters from the skin, lies the division of the MCA.
With the LVO detector assembly 20 in place on the patient's head 114, the user now operates the LVO detector assembly 20. Referring now to
At step 210, the process compares each calculated left side-right side differential versus a threshold value stored in the data storage unit 106. If the calculated differential is less than the stored threshold value, the patient is not having an LVO incident, and no LVO alert is generated (Step 212). However, on the other hand, if the calculated differential is greater than the stored threshold value, the patient is having an LVO incident, and an LVO alert is generated (Step 214), which is displayed on the LVO alert screen 101; informing the user that he or she should send the patient 112 immediately to an EVT-capable hospital. The LVO detector assembly 20 of the present invention makes this determination using a single reflection datapoint capture and does not have to make multiple measurements to measure blood flow in the brain to make complex cerebral oximetry calculations.
There are different ways to set a threshold and different ways to measure an amplitude difference against a threshold in differing embodiments of this invention. Referring now to
Although certain embodiments and features of an LVO detector assembly have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all embodiments of the teachings of the disclosure that fairly fall within the scope of permissible equivalents.
This application is a continuation-in-part application of U.S. Ser. No. 16/685,985 filed on Nov. 15, 2019, which is a division application of U.S. Ser. No. 15/828,840 filed on Dec. 1, 2017, which claims priority to U.S. Provisional Patent Application Ser. No. 62/486,177 filed Apr. 17, 2017, and to U.S. Provisional Patent Application Ser. No. 62/517,549 filed Jun. 9, 2017; the disclosures of each application which are incorporated herein in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62486177 | Apr 2017 | US | |
| 62517549 | Jun 2017 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15828840 | Dec 2017 | US |
| Child | 16685985 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16685985 | Nov 2019 | US |
| Child | 18423744 | US |
