The illustrated embodiments are directed to a unique approach to rapidly cool the brain to deep hypothermia (20 to 25 degrees Celsius using aCSF cooled to 1-10° C.) safely and rapidly for the prevention of brain death in cases of lack of circulation to the brain, including such diseases as cardiac arrest due to myocardial infarction, stroke, and exsanguination.
Fifty years ago, Professor Robert White demonstrated that cooling the brain of a monkey down to 15 degrees Celsius would protect the structure and function of the brain without blood circulating to the brain for one hour when tying all major vessels in the neck. When the ligatures around all the vessels of the neck were released after one hour, the monkey was given time to return to room temperature, after which testing showed no deterioration of memory, problem solving, and motor activity.
Professor White's novel work is currently being used successfully today by cardiothoracic surgeons who repair the aortic arch with an aortic prosthesis such as in cases of Marfan's syndrome with dissection of the aorta as depicted in
The brain can be put into a state of suspended animation despite having no blood flow by lowering its temperature to extreme hypothermia. A 29-year-old radiologist, Anna Bägenholm, was reported in The Lancet (355 (9201) 375-376) to have been frozen in accidental submersion to 13.7 degrees Celsius with a flat electrocardiogram. Upon resuscitation and return to normothermia, she had complete recovery of all mental faculties. Samuel Tisheman, MD, who has Department of Defense funding, was reported in November 2019 to treat a severely traumatized patient by cooling the brain to extreme hypothermia by using refrigerated saline into the cerebrovascular circulation. After two hours of hypothermia he was able to complete surgical repair and then resuscitate the patient.
Children who had fallen into a frozen lake have been reported to survive with no apparent brain damage after being submerged for one hour or longer in extreme hypothermia—Adults under similar challenging situations will not survive the freezing waters, for children may have an open fontanel as well as thinner skulls allowing for rapid cooling of the brain. Today, infants and children who are in danger of ischemic brain damage are treated with moderate to mild hypothermia with improved survival and less brain damage compared to children without lowering of their systemic temperature.
Many reports have studied the use of mild to moderate hypothermia, lowering the body temperature to only 33 degrees Celsius, in cases of heart attack with varying reports of success in outcome analysis. Lowering the body temperature to less than 33 degrees Celsius can result in cardiac arrhythmia due to deleterious effects on the ventricle, and bleeding problems due to interruption of platelet aggregation resulting in hemorrhage.
In cases where there is interruption of blood to the brain, we may have only minutes before there is irreversible brain damage. While cardiopulmonary resuscitation (CPR) has been the standard treatment for cardiac arrest, even successful cases may result in a stroke of brain tissues with significant disability. Besides cardiac arrest, massive stroke and exsanguination are major life-threatening problems that need to be treated within the first few minutes of lack of circulation to the brain. It is no wonder that the military is anxious to find a way to extend survival of the brain for one hour or longer with circulatory arrest. This search for a method to extend the “golden hour” will give the treating physician a chance to treat the immediate problem and its cause. If the brain can be put in suspended animation for one hour or longer, it will result in a paradigm shift in medical care for patients threatened with immediate brain death! Restoration of circulation and repair of injured organs and tissues will be possible if the brain can be protected from ischemic damage by utilizing deep hypothermia rapidly and effectively. Given one hour and not just five minutes time, the treating physician will have a chance to save the patient.
In the range of profound hypothermia (<14 degrees Celsius), such low temperatures may be achieved using the technique of cooling the brain with artificial cerebrospinal fluid (aCSF). Although subject to clinical refinement, for the purpose of this patent, a target temperature range of “deep” hypothermia is used consistent with the surgical technique of “deep hypothermic circulatory arrest” (DI-ICA). A review of the history, current work, and rationale for this paradigm shift in approaching deep hypothermia of the brain is presented.
The illustrated embodiments of the present invention provide an apparatus and method for prevention of brain death due to interruption of intracranial circulation to the brain due to cardiac arrest, stroke, loss of blood due to exsanguination, and other causes. By selectively cooling the brain, it can be put into “suspended animation” for one hour or longer without circulating blood flow. Instead of only five minutes to save a patient with impending brain death, the treating physician will have one hour or longer to save the life of a patient. By cooling the cerebrospinal fluid directly, it is possible to cool the brain without directly entering the cerebrovascular circulation through cannulating the aorta or large vessels to the brain. The time it would take to cannulate the circulation makes it difficult to do rapidly, and the problems of systemic cooling may result in arrhythmias and hemorrhage.
Therefore, a paradigm shift in cooling the brain rapidly requires a new approach. The apparatus of the illustrated embodiments is necessary in order to rapidly enter the cisterna magna safely, accurately, and atraumatically. Since the first person available to insert a needle into the brain may be a paramedic, the procedure must be full-proof, easy to use, and rapidly administered. Once in place, the needle must be immobilized to a stationary anatomic site, and the sharp cutting tip of the needle must change its shape to prevent damage to brain tissue in the cisterna magna and the brainstem. In the case of battlefield situations, the design of a similar needle system for entry into a large vessel such as the femoral artery must be done safely and rapidly when used by a paramedic.
Method for Cooling of the Bruin Through the Cisterna Magna
Safety, accuracy, and speed are the hallmarks of the illustrated embodiments to rapidly prevent brain death in emergencies dealing with patients who have acute interruption of circulation to the brain which will result in brain death. Clinically, the brain can be put in suspended animation during surgery to replace a dissecting aortic aneurysm by pumping refrigerated saline into the brain through a bypass into the subclavian artery. This is quite successfully done throughout the world in humans.
Our laboratory studies demonstrate that the brain in the experimental animal can be rapidly cooled to deep hypothermia, or even lower to profound hypothermia. Cooling the cerebrospinal fluid (CSF) rapidly by circulating cooled artificial (aCSF) about the brain will also result in cooling the central nervous system (CNS) by targeting the blood vessels in the basal cisterns as well as the brain within the subarachnoid space. We have found that entry into the subarachnoid space can be accomplished rapidly and safely by entering the cisterna magna from the cranial-cervical junction posteriorly or from a lateral approach below the mastoid bone. Because of the proximity of the entering needle to the brainstem and to the vertebral arteries, this must be done under direct visualization using ultrasound direction through and about the needle. There must be a vent placed in the forehead (near the hair line) to evacuate aCSF out of the head and to allow for convection cooling. This vent is a new design for a trephine that is rapidly inserted, is stable, is safe from injury to the brain, is accurately placed, and is done by a single person semi-autonomously. There is a temperature differential with cooler fluid posteriorly near the occiput with the patient lying supine, while the exiting fluid is warmer near the frontal lobe. The subarachnoid space is relatively large in older patients, giving greater cooling effect with a larger volume of aCSF.
A different configuration allows for aCSF to exit the trephine and be recycled into the cisterna magna. The vent opening is connected to a sterile drainage system or to a pump system to recycle aCSF that is controlled via information from the tubing in the forehead for temperature and pressure measurement. Temperature of the exiting aCSF is monitored as well as the entering temperature at the cisterna magna. The cooling system is integrated with a refrigeration unit and a peristaltic pump. If a closed system is used, a filter system is in series with this closed system to remove debris and contaminants and infectious agents from the pathway from the front of the brain where the fluid is exiting; thereby, convection cooling will occur resulting in better cooling of the brain rapidly. A virtual “pump” created by convection cooling will act as an additional “motor” within the skull to facilitate rapid cooling.
In effect, the recirculating cooled aCSF is in a closed and sterile system that will cool the cisterna magna and structures of the brain within the subarachnoid space. Initial cooling is provided to the vessels at the base of the brain thence through the cooled blood circulating through the brain tissue. The cooled aCSF will directly cool the base of the brain and vital structures including memory. From there the cooled aCSF will pass around the brain within the subarachnoid space. In the supine position there is a differential in temperature between the cool fluid near the occiput and the warm fluid at the front of the brain where the fluid is exiting, thereby, convection cooling will occur resulting in better cooling of the brain rapidly. A virtual pump created by convection cooling will act as an additional pump within the skull to facilitate rapid cooling.
While the apparatus and method has or will be described for the sake of grammatical fluidity with functional explanations, it is to be expressly understood that the claims, unless expressly formulated under 35 USC 112, are not to be construed as necessarily limited in any way by the construction of “means” or “steps” limitations, but are to be accorded the full scope of the meaning and equivalents of the definition provided by the claims under the judicial doctrine of equivalents, and in the case where the claims are expressly formulated under 35 USC 112 are to be accorded full statutory equivalents under 35 USC 112. The disclosure can be better visualized by turning now to the following drawings wherein like elements are referenced by like numerals.
The disclosure and its various embodiments can now be better understood by turning to the following detailed description of the preferred embodiments which are presented as illustrated examples of the embodiments defined in the claims. It is expressly understood that the embodiments as defined by the claims may be broader than the illustrated embodiments described below.
Animal Studies:
The cisterna magna, located at the base of the brain, was chosen to be the entry point for the cooling devices duc to ineffective previous attempts to cool the brain via a lumbar puncture. Entering through the spinal canal resulted in a rise in temperature of the aCSF due to the warmth of the circulating vessels in the spinal canal. By entering the largest cistern, the cisterna magna, a 17-gauge needle can be placed into the subarachnoid space and used to circulate cooled saline out through a vent in the forehead. Using this methodology, initial work on more than 50 recently deceased pigs provided promising results and encouraged testing in vivo.
To test in vivo, our approach was combined with thermistors, placed at various depths (5 mm increments) in the brain to monitor the temperature of the tissue and therefore the effects of the circulating cooled aCSF as depicted in the CT scan in
Contrarily, this radical system is designed for extreme cases of emergency, specifically targeting patients who are experiencing shock or have little to no blood flow to the brain. These cases would be more advantageous as there would be minimal heat from the circulating blood making cooling the brain even easier and therefore maximize the time for intervention.
Results from our in vivo studies give support to our approach of cooling the brain by cooling the CSF directly and allow convection cooling to increase the cooling effect in the subarachnoid space adjacent to the cortex where the neurons are located. Moreover, since the CSF flow from the cisterna magna starts at the base of the brain, cooling of the memory circuitry is cooled early. Since the vertebrobasilar circulation is adjacent to the cisterna magna, there will be cooling of the circulating blood without cannulating any blood vessel, resulting in additional cooling of deep structures.
We have demonstrated in our live animal studies the efficacy of the cooling system as shown ill
The disclosed apparatus and method provide a successful and safe way to rapidly cool the brain to prevent brain death by using deep hypothermia. A needle 3 is placed into the cisterna magna 1 safely, rapidly, and accurately to circulate cold artificial cerebrospinal fluid (or other isotonic solution) into the intracranial and subarachnoid space 2. By lowering the temperature of the artificial cerebrospinal fluid (aCSF) and circulating it around the blood vessels of the basal cisterns, the circulation of the brain will be cooled. Once the cooled aCSF reaches the subarachnoid space 2 especially in the back of the brain by a computer-controlled peristaltic pump, convection cooling will begin, for an exit will be made through the frontal bone for egress of the warmer fluid. The exiting aCSF will then be sterilely collected as illustrated in
Alternatively, it will be cooled and filtered outside the body and recirculated as shown in
This circulation of cooled aCSF in the subarachnoid space rapidly cools the entire brain including the structures at the base of the brain as well as the grey matter on the outer surface of the brain.
In
Thus, the disclosed apparatus and method successfully produce deep hypothermia of the brain safely and rapidly. In addition, this method will also be effective in cooling the spinal cord as described in
Cardiac arrest, stroke, and exsanguination can result in brain death in five minutes unless the brain can be placed into suspended animation rapidly, giving the treating physician up to one hour or longer to save the life of the patient, which is provided by the apparatus and method of the disclosure.
The disclosed apparatus includes an ultrasound guided needle 3 as described in
To rapidly cool the brain to prevent brain death by using deep hypothermia, it is crucial that a needle 3 be designed to be placed into the cisterna magna 1 safely, rapidly, and accurately to circulate cooled artificial cerebrospinal fluid or other isotonic solution into the intracranial and subarachnoid space 2.
The lateral neck below the mastoid bone may be easier for the paramedic or nurse to locate and access. It is easily identified as the bony prominence behind the ear as shown in
Spinal Cooling
Prevention of the Sharp Needle Tip from Cutting the Brain
To prevent the sharp tip of the needle 3 from puncturing or lacerating the cisterna magna 1 or other neurological tissues in the brainstem, spinal cord, and brain, the tip of needle 3 is made of a shape-memory alloy that changes it shape when the temperature changes to a predetermined range as shown in
In the case of using a similarly designed needle 3 for rapid entry into a large vessel such as the femoral artery, the phased array cannula 19 within the tip of needle 3 delineates the various tissues until the needle 3 enters the artery, while the paramedic uses the handheld video and audio unit as depicted in
Motorized Insertion of Needle
Semi-autonomous or robotic technology has been in general practice for decades and is used in the navigation of self-driving cars, etc. Based on radar, camera data, and GPS information the “self-driving” car uses artificial intelligence to program the car to maneuver its way from home to work safely. Similarly, we utilize 3-dimensional ultrasound information from the tip of the needle to use artificial intelligence to program the servomotors to direct the needle to safely travel through the skin, fat, muscles, tendons, and blood vessels on its way to the cisterna magna. Once in the cisterna magna, the needle automatically locks in place to prevent damage to neurological tissue. This requires expert software development all of which has been done in other industries. The novelty of this invention is the application of a custom developed software to enable semi-autonomous or robotic insertion of the needle with several orders of magnitude greater precision than a self-driving car, in the order of a fraction of an mm within the target site.
As disclosed in Mathiassen et. al. “Visual Servoing of a Medical Ultrasound Probe for Needle Insertion,” 2016 IEEE International Conference on Robotics and Automation (16-21 May 2016), percutaneous needle insertion guided by ultrasound imaging is routinely performed in hospitals. Automating these procedures increases placement accuracy and lowers time usage of health care personnel to perform these procedures. An important step in the automation is the estimation of the needle orientation and position in the ultrasound image. One approach to estimate the needle orientation and position is to have the needle aligned with the image plane of the ultrasound probe. Aligning the needle with the plane is difficult, even with accurate measurements and calibration of both needle and probe. Visual servoing to move the ultrasound probe is performed using a robot to align the image plane of the probe with the needle, which solves the problem of needle alignment. The method segments the needle and updates a set of visual features based on a model of the needle. A state machine is used to keep track of the alignment process, and different visual features are used to control the probe in the different states.
The methods, algorithms, and apparatuses of using images collected from cameras to guide the steering, braking, and accelerating a vehicle exist in the field. For example, see “Autonomous Driving Control Device,” U.S. Pat. Appl. 15/413,568 and “Control Arrangement Arranged To Control An Autonomous Vehicle, Autonomous Drive Arrangement, Vehicle And Method” U.S. Pat. No. 9,566,983, both incorporated herein by reference. In our technology, instead of using images from cameras, we use images from our ultrasound probe. Instead of controlling the movement of a car, we control the movement of the probe. Overall, the concept and approach are similar. The algorithms will be different to accommodate the use of a different kind of image and the control of a different kind of actuation mechanisms. The means to make these adjustments are well within the ordinary skill in the art. There have been numerous patents issued on using ultrasound images as feedbacks to control a medical device. In particular, “Feedback in Medical Ultrasound Imaging for High Intensity Focused Ultrasound” U.S. Pat. No. 8,343,050, incorporated herein by reference, describes the use of ultrasound imaging to detect and monitor the small change in tumorous tissues as a result of applying high-intensity focused ultrasound (HIFU) to the tissues. The image is used as a feedback to control the focal point, intensity, and duration of the HIFU. In our case, we are using the same ultrasound imaging technique as a feedback to control the movement of the probe. The algorithm is adapted to control the servo motor instead of the HIFU. The basic principles and approach are the same.
A motorized inserter for the needle 3 to enter the cisterna magna 1 requires a micro-controller 38 with artificial intelligence to control a servomotor 39. Servomotor 39 is a rotary actuator or linear actuator that allows for precise control of angular or linear position, velocity, and acceleration. It is comprised of a suitable motor coupled to a sensor for position feedback as illustrated in
In the case of insertion of a needle 3 into the femoral artery, a phased array ultrasound system will give anatomic information to facilitate the identification of the femoral artery in distinction to a femoral vein. Moreover, if the pulse of the femoral artery cannot be felt, then the anatomic information from the ultrasound system will better locate the femoral artery. A semi-autonomous ultrasound needle unit 14 to be inserted into the femoral artery also requires fixation of the unit as shown in
Method and Device to Create a Safe and Rapid Insertion of a Trephine through the Skull:
In order to create an exit point in the forehead for cooled fluid to leave the subarachnoid space 2 during irrigation of aCSF to cool the brain, trephining of the hone in the skull must be accomplished safely, quickly, bloodlessly, and with precision by a single health care person. The unit must be self-contained including transducers and a semi-autonomous or robotic motorized insertion device as described in “Method of Insertion of the Needle” 26 in a “box” which will be attached to the area of the frontal bone. The “screw” 30 includes a hollow shaft within a 3 to 4 mm inside diameter screw with a trocar 31 which is carefully screwed into the cranial bone. Information received from the transducers within the device 26 control the semi-autonomous or robotic insertion of the screw 30 through the bone and safely into the subarachnoid space 2.
The insertion method for the semi-autonomous trephine unit includes the following: after choosing the point of entry, usually in the upper forehead near the hair line, an incision is made with a scalpel along the line of Kraissl in the natural skin fold from the skin down to the subcutaneous tissues overlying the frontal bone. Sterility is maintained, anesthesia with a vasoconstrictor is injected into the skin, and the length of the incision is between 1.0- and 1.5-mm. Insertion of self-retaining retractors are placed into the wound to give stability and hemostasis. The box unit 26 and the screw 30 are inserted into this opening and fixated to the retractors. The semi-autonomous or robotic insertion is activated and carefully directed through the bone into the subarachnoid space 2. The ultrasound data is obtained from four or more transducers 40 within the trephine “box” attached to the scalp. The micro-controller 38 with artificial intelligence directs the servomotor 39 which in turn screws the trephine into the skull. The final configuration is very stable and mobilized by the screw in the frontal bone as depicted in
The screw 30 in the frontal bone is rigidly attached, quite stable, and well fixated. It serves as one point upon which a headband is taken to the back of the head and attached to two or three points posteriorly to give greater stability during insertion of the ultrasound needle into the cistern magna as depicted in
At the conclusion of the procedure, removal of the screw 30 can be done with local anesthesia, bone wax, if needed, placed into the small 3 to 4 mm opening, and a single suture placed across the skin. Since the incision is made in the line of Kraissl, there is minimal scarring, with the incision being in the natural skin fold.
In addition, for its central role in cooling the brain by creating an exit port, the disclosed method and device can be used in other brain operations including surgery for epidural hematoma, surgery for subdural hematoma, and for stereotactic intracranial surgery.
Hence an approach to the treatment of intracranial brain tumors, especially glioblastoma, is presented here combining the ultrasound needle 3 with the trephine 33.
A Novel Approach to the Diagnosis, Localization, and Management of Glioblastoma:
Glioblastoma, the most common intrinsic brain cancer, defies early diagnosis and treatment. From diagnosis with conventional imaging and brain biopsy to inevitable death of the patient within 4 to 16 months, these patients frequently undergo neurosurgery, radiation, and chemotherapy with little hope for a cure. We have the technology and expertise to accomplish characterization and diagnosis of disease, perhaps without taking a formal biopsy of the tissue by studying the tissue signature from data using ultrasonography. The disclosed approach is to do minimally invasive insertion of an ultrasound needle into the skull and into the subarachnoid space to scan the brain with a 30-degree field of view and a depth of up to 2.5 cm. Ultrasound data from the needle tip will image the tumor in 3-dimensions, and then be used to semi-autonomously or robotically insert the needle tip to within 1 mm of the target tissue. This requires precision and the development of servo-controlled devices to trephine 33 through the skull and to guide the ultrasound needle 3 to the target tissue.
The current state of the art for ultrasound imaging of the brain is to use transducers on the scalp and transmit energy through the bony skull. Low frequency transducers have the advantage in transmitting through the tissue of the scalp and bone, but resolution is low. In order to have high resolution imaging at the cellular and/or tissue level, the ultrasound transducer must be closer to the object and have high frequency imaging. This poses a dilemma. Therefore, the ideal ultrasound design would be to have a non-invasive device with penetration to the site of the disease with high frequency transducers. This can be done by making a trephine 33 opening through the bony skull sufficiently small to be minimally invasive, and using an ultrasound unit designed to be placed within the profile of a needle 3. Moreover, the ultrasound needle 3 is inserted into soft tissue of the body using semi-autonomous or robotic motorized systems with precision. Recent basic laboratory research by Sheehan et al. reported positive effects of use of ultrasound radiation to augment the effect of medications on the death of glioblastoma cells in culture (Kimball Sheehan et al. Investigation of tumoricidal effects of sonodynamic therapy in malignant glioblastoma brain tumors. J. Neuro-Oncology. 148, 9-16, 2020).
What is disclosed above is a use of an ultrasound needle 26 and semi-autonomous or robotic trephine 33 used beyond the initial purpose of cooling the brain in the case of brain death. The basis of this approach is sound, for it utilizes the elements in the tip of the needle 3 used for imaging, to be programmed to generate energy from the same transducers in the tip of the same needle 3. This method for the treatment of glioblastoma of the brain depends on an intimate relationship of the semi-autonomous or robotic ultrasound needle 26 and the semi-autonomous or robotic trephine 33 joining together to form a unique, precision, and stable platform. The design and the characteristics of the ultrasound needle 26 and the trephine 33 have been described above. The application of this technology creates a new approach to the diagnosis, localization, and management of glioblastoma of the brain.
Moreover, the ultrasound needle includes at least 64 elements within a 2 mm diameter cannula in the tip of the needle has a definition to less than 0.1 mm, with a field of view of 30°, and a depth of up to 2.5 cm. It is capable not only of imaging the shape and size of the tumor, but also is able to render specific tissue characteristics when ultrasound is passed near or within the tumor and through normal tissue. Therefore, tissue diagnosis may be done with ultrasound alone. After the semi-autonomous or robotic insertion of the hollow screw 30 is made down to the level of the subarachnoid space 2, the trocar 31 of the screw 30 is removed and replaced with the ultrasound needle 3 surrounded by its own semi-autonomous or robotic unit 26. These two units act as one and are securely attached, giving extreme accuracy and fixation while the needle 26 is sent deeper within the cranial cavity.
Ultrasound (US) guided biopsy is a medical procedure routinely performed in clinical practice. This task could be performed by robotic systems to improve the precision in the execution and then the safety for the patient. Both robotic and human procedures greatly benefit from real-time localization of the needle in US images. This information guides the robot or the specialists to the correct target point avoiding critical structures. In Mathiassen et. al. “Real Time Biopsy Needle Tip Estimation in 2D Ultrasound Images,” 2013 IEEE International Conference on Robotics and Automation (6-10 May 2013) a needle localization method able to extract the needle orientation and the tip position in real time from B-mode US images is disclosed. The results show an improvement in term of localization accuracy compared to previous works in literature.
As disclosed in Mathiassen, “Robust Real-Time Needle Tracking in 2-D Ultrasound Images Using Statistical Filtering”, IEEE Transactions on Control Systems Technology, 2017, 25 (3) 966-978, percutaneous image-guided tumor ablation is a minimally invasive surgical procedure for the treatment of malignant tumors using a needle-shaped ablation probe. Automating the insertion of a needle by using a robot increases the accuracy and decreases the execution time of the procedure. Extracting the needle tip position from the ultrasound (US) images verifies that the needle is not approaching any forbidden regions (e.g., major vessels and ribs), and also is used as a direct feedback signal to the robot inserting the needle. A method for estimating the needle tip has previously been developed combining a modified Hough transform, image filters, and machine learning. A method of introducing a dynamic selection of the region of interest in the US images and filtering the tracking results using either a Kalman filter or a particle filter is also known. The results show a significant improvement in precision and more than 85% reduction of 95th percentile of the error compared with the previous automatic approaches. The method runs in real time with a frame rate of 35.4 frames/s. The increased robustness and accuracy make the disclosed algorithm usable in autonomous or robotic surgical systems for needle insertion.
Since the hollow core within the screw 30 is shaped like a cone, there will be some play of the 2 mm diameter needle within the 3 to 4 mm hollow screw trephine. Therefore, control with the semi-autonomous or robotic motor allows the needle 3 to extend its range to cover a greater area than 30°. Imaging of the tissue immediately in front of the ultrasound needle to a depth of up to 2.5 cm will delineate the shape and size of the tumor. Moreover, because tissue density can be determined with ultrasound it will be possible to diagnose glioblastoma cells from normal tissue. To corroborate the ultrasound diagnosis, it is possible to do a needle biopsy through the needle 3 for confirmation.
If it is decided to direct the needle 3 deeper into the brain tissue with the semi-autonomous or robotic control and ultrasound information, it can be slowly and precisely placed up to the border of the tumor 34 or even within the tumor 34. The transducers can then be programmed to generate ultrasound energy in front of the needle tip 3 into the tumor 34. The addition of chemotherapeutic agents, immune therapy, or other modality can be given through the needle tip 3 in well-controlled small microliter volumes. The effect of the injection into the tissue can be ascertained by using ultrasound imaging to look for abnormal tissue response. An intracranial pressure gauge (not shown) shows if there is swelling of the tissue causing increased intracranial pressure. If need be, the hypothermia of the brain procedure can then he applied to cool the brain and prevent swelling.
Semi-Autonomous or Robotic Insertion of the Ultrasound Needle:
The semi-autonomous or robotic insertion of the needle into the cisterna magna is accomplished by using servo-controlled motors guided by information obtained from the 64 elements within the tip of the needle 3. The information will have a 3-dimensional space with a 30-degree range and a depth of up to 2.5 cm as shown in
Semi-Autonomous or Robotic Insertion of Screw Trephine:
The semi-autonomous or robotic insertion of the screw trephine 33 through the skull into the subarachnoid space will use a servo-controlled motor (not shown) guided by information obtained from four or more transducers in the unit 26 placed on the scalp. In
Many alterations and modifications may be made by those having ordinary skill in the art without departing from the spirit and scope of the embodiments. Therefore, it must be understood that the illustrated embodiment has been set forth only for the purposes of example and that it should not be taken as limiting the embodiments as defined by the following embodiments and its various embodiments.
Therefore, it must be understood that the illustrated embodiment has been set forth only for the purposes of example and that it should not be taken as limiting the embodiments as defined by the following claims. For example, notwithstanding the fact that the elements of a claim are set forth below in a certain combination, it must be expressly understood that the embodiments includes other combinations of fewer, more or different elements, which are disclosed in above even when not initially claimed in such combinations. A teaching that two elements are combined in a claimed combination is further to be understood as also allowing for a claimed combination in which the two elements are not combined with each other but may be used alone or combined in other combinations. The excision of any disclosed element of the embodiments is explicitly contemplated as within the scope of the embodiments.
The words used in this specification to describe the various embodiments are to be understood not only in the sense of their commonly defined meanings, but to include by special definition in this specification structure, material or acts beyond the scope of the commonly defined meanings. Thus, if an element can he understood in the context of this specification as including more than one meaning, then its use in a claim must be understood as being generic to all possible meanings supported by the specification and by the word itself.
The definitions of the words or elements of the following claims are, therefore, defined in this specification to include not only the combination of elements which are literally set forth, but all equivalent structure, material or acts for performing substantially the same function in substantially the same way to obtain substantially the same result. In this sense it is therefore contemplated that an equivalent substitution of two or more elements may be made for any one of the elements in the claims below or that a single element may be substituted for two or more elements in a claim. Although elements may be described above as acting in certain combinations and even initially claimed as such, it is to be expressly understood that one or more elements from a claimed combination can in some cases be excised from the combination and that the claimed combination may be directed to a sub combination or variation of a sub combination.
Insubstantial changes from the claimed subject matter as viewed by a person with ordinary skill in the art, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are defined to be within the scope of the defined elements.
The claims are thus to be understood to include what is specifically illustrated and described above, what is conceptionally equivalent, what can be obviously substituted and also what essentially incorporates the essential idea of the embodiments.
The present application claims priority to U.S. Provisional Patent Application, Ser. No. 62/905,996, filed on Sep. 25, 2019 pursuant to 35 USC 119, incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2020/051084 | 9/16/2020 | WO |
Number | Date | Country | |
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62905996 | Sep 2019 | US |