WO2004070350A2

WO2004070350A2 - New parametric imaging solution

Info

Publication number: WO2004070350A2
Application number: PCT/US2004/001319
Authority: WO
Inventors: James B. Seward
Original assignee: Mayo Foundation For Medical Education And Reserch
Priority date: 2003-01-29
Filing date: 2004-01-20
Publication date: 2004-08-19
Also published as: WO2004070350A3

Abstract

The unique aspect of the present invention is the extraction of parametric information from the fundamental image and reformatting this new information into a new geometric or parametric image. This presentation assists in explaining such events, and ultimately describing why something happens by invoking the flow of time. Quantum descriptions of distributions resolve events into measurable units of simplicity and comprehensibility and can be looked upon a high-level simplicity derived from low-level complexity. Surrogates of physiologic phenomena can be displayed as geometric images suited to the human’s four-dimensional comprehension of reality.

Description

NEW PARAMETRIC IMAGING SOLUTION

FIELD OF THE INVENTION

[0001] This invention relates to a new and novel means of expressing information.

The innovation is robust and can be generalized to the field of imagery, however for purposes of understanding ultrasound imagery is principally discussed. More particularly, the present invention relates to creation of a new information image using simple rules and/or topographical assimilation of component parts to visualize the complexities of physiological events.

BACKGROUND OF THE INVENTION

[0002] Medical Imagery: In the field of medical imagery, one can acquire ever more knowledge of reality by solving problems and finding better explanations. The universe tends to reward us for understanding and punish us for not understanding. This fact is very apparent in the science of diagnostic imagery. However, the more closely natural phenomena are examined the more complicated they appear, yet the last few decades of research it has been discovered that beneath those complexities lie deep simplicities, laws of nature. Herein we describe a unique and new means of expressing natural phenomena as understandable, quantifiable geometric pictures. In order to comprehend the complexities on reality, we must do more than just explain higher-level complexities in terms of lower-level simplicities (i.e., the reductionist or molecular approach). It is essential to explain why we can deal with natural events as if they were simple. For example nature is chaotic and unpredictable at the molecular level but extremely deterministic at the macro-level. Within the capacity of our 4- dimensional senses the complexity of nature is hidden from our view (example: we perceive wind but not the pressure fronts, which determine the event). However, there are structured patterns that collapse an underlying sea of chaos, which are conditioned and created by context. In order to observe nature within understandable spatial scales we must either amplify things (microscope) or bring them closer (telescope). It has been found that events have deep similarities that obey the same fundamental rules (example: wind follows the general rule of pressure differences). The disclosure herein expresses physiology as a mathematical event using simple rules regarding events or their component parts (quanta) and expressing this information as a geometric display (image). The rules of this new science use approximations of how nature behaves, or consequences of behavior (a quantum picture,

I herein called a parametric image). The patterns exploited may be imperfect, mere approximations, but they are good approximations and extremely informational. In an area of natural science where really accurate measurements or repeatable experiments are not possible, the use of models is preferred over laws. The model (parametric image) is a pattern, which can be used very effectively to bring certain aspects of nature into understandable control.

[0003] For example medical ultrasound over the past 25 years has evolved to become one of the most commonly performed imaging and hemodynamic examinations. Current ultrasound machines can replicate many functions previously obtained by invasive cardiac catheterization, non-invasive magnetic resonance imaging or computed x-ray tomography (CT). Functions of more invasive technologies include: 1) ability to obtain anatomic images; 2) qualitatively and quantitatively assess function, shape, geometry and morphology, etc. (ejection fraction, fractional shortening, etc.); 3) measure hemodynamic and muscle function, (pressure, gradient, elastance, viability, etc.); 4) visualize blood flow (i.e., Doppler angiographic substitute); 5) visualize distribution of flow or function; 6) use microbubbles, tracers, etc.); visualize and quantitate microstructures (e.g., myofibers); etc. The unique advantages of using ultrasound include: 1) non-invasive energy source (body surface, etc.) as well as (ultrasound tipped catheters, etc.); 2) no ionizing radiation (a safe repeatable ultrasound energy source); 3) comparatively low cost; 4) ability to simultaneously and continuously obtain function, hemodynamics, flow information, muscle dynamics as well as morphologic images; 5) technology capable of being fabricated into different sizes and shapes (e.g., surface, laptop, pocket, hand-carried, catheter tipped, implantable or micro/macro- scaled), 6) high temporal and spatial resolution, and etc. Limitations of the ultrasound examination include: 1) instantaneous acquisition of large amounts of intertwined information, 2) noisy images, 3) requires personal acquisition and interpretation of acquired information, and 4) with increased information complexity there is increased subjectivity and reduced reproducibility, etc. Each technology will invariably have limitations as well as strengths. It is the limitations of virtually all imaging solutions, which are specifically addressed in this claim.

[0004] Computer Interface: With the incorporation of more sophisticated computer interfacing, in the later part of the twentieth century, diagnostic ultrasound entered into the era of increased information acquisition. The prerequisites for this change include use of newer sophisticated information acquisition and management techniques, reconstruction or assimilation of multiple forms of information, segmentation of the pertinent or most meaningful information, quantitation and compressible display of the result. Backscattered signals carry decipherable information about the interaction of energy with the physiologic and structural (morphological) features of the interrogated environment (i.e., tissue, muscle, blood, etc.). For example with medical ultrasound newer information acquisition techniques include tissue Doppler imaging (TOT) and strain-rate imaging (SRI), harmonic imaging, pulse-inversion imaging, and pulsed and intermittent imaging, higher-dimensional imaging (i.e., 3- and 4-dimensional images), contrast echo (i.e., gas particles injected into the blood stream, which act like a image tracer), etc. One, but not the sole, new acquisition device pertinent to the present invention is represented by and ultrasound catheter (US 6,3998,736 Bl). Other acquisition solutions include transcutaneous, transesophageal, transvaginal, rectal, urethral, abdominal, etc. devices. New information gathering is enhanced by sophisticated broadband receivers, hardware and software, which allows the acquisition of micro-resolution events emanating from the interaction of an energy source with the interrogated environment. [0005] New Expression of Reality: In the past few years, within the field of physics, it has become increasingly evident that simple rules can give rise to simple as well as extremely rich expressions of reality (i.e., simple rules can be used to express simple or complex behavior). For better understanding of this evolution in physics the following brief background is offered.

[0006] Reductionism is the study of smaller and smaller components of an intact natural event or phenomenon and seeks to explain patterns of nature, obvious or hidden, as composed of individual parts arising form underlying internal building blocks (quanta). However, it is now well understood that this "molecular approach" is of little value and understanding the rich behavior of the intact event. Natural physiological events are derived from complicit interaction of numerous simple and complex, which are under the influence of external complex and simple rules. Reality, the nature of being, can not be understood if one is ignorant of the higher level principles and interactions of a multitude of component events. Such knowledge reveals that the principles are collective or emergent and arise from interactions among the component parts. Based on this knowledge, a new way of comprehending reality or natural events has evolved, which we have descriptively named "parametric imaging". Briefly the science can be best understood as a stepwise management and display of information: 1) fundamental examination is carried out using, for example, an ultrasound device (hand-held, catheter, transesophageal, transvaginal, etc.); 2) ultrasound information is received from an ultrasound transducer (phased array, linear array, multidimensional array, wireless transducer), in different formats (fundamental image, Doppler information, functional information, flow information, etc.), in different forms of composite information (analog, digital, digitized, quanta, molecular, pixel, etc.), displayed in different image formats (1-, 2-, 3-, 4- and higher dimensional image, linear or picture Doppler, variable dimensional color flow Doppler, etc.); 3) Parametric computer (i.e., mathematical separation, classification, rendering, etc.) manipulation into families of desired information; and lastly 4) geometric display (i.e., planar, area, volume) of new, unique, natural parametric information (i.e., motion, change, time, flow, stretch, and infinite other parameters). Parametric imaging of information is relevant to the evolution of the imaging sciences of medicine. Although the physics of ultrasound image creation described herein is new and novel, the adjective "parametric" has been in general scientific use for many years to describe various scientific and mathematical preconditions.

[0007] Quantum information: Recently, quantum information scientists have begun to fathom the relationship between classical and quantum units of information. From this knowledge, novel means of expressing information are being expressed which emphasize the pivotal importance of quantum features called entanglement, which entails particular connections between simple, different or interrelated behavior. Interestingly, most systems lose their quantum nature as their size increases (for example, the whole event appears to be more simple or coherent than any of its component disparate parts). As described above the knowledge of a component part in general tells you little about the reality of the whole or intact system. Large quantum systems generally interact strongly with their environment, causing a process of decoherence, which destroys the systems probabilistic quantum properties (a condition of emergent or determmalistic chaos). The new expression of reality takes three essential steps: 1) a physical resource of building block such as a molecule, bit, pixel, mathematical integer, etc. (i.e., likened to current fundamental ultrasound information technology); 2) an information-processing task such as taking the physical resource and creating a higher dimensional topographic distribution or map, and creating an understandable graphic, picture or realistic event depiction (i.e., parametric image); and 3) identifying criteria for successful completion of step 2 (i.e., does the parametric image express the real event such as the presence of cancer, or a myocardial infarction). This could include documenting the relationship of a distribution of quantum events (physical resources) to a natural event or phenomenon. Some of the basic questions of the new information science is "what is the minimal quantity of the physical resource (step #1) needed to perform the information processing task (step #2) which satisfies the criteria for success (step #3)?" The claims described herein develop a quantum approach to ultrasound information and specifically addresses this stepwise approach to the creation of a new image presentation, which we have arbitrarily named "parametric".

[0008] A general theme of this new information science is that questions of elementary processes or reality lead to unifying understandable concepts that allow insight into more complex processes (i.e., better understanding complex physiological events). This information process is described as a bottom-up approach (i.e., starting with simple elements, one builds larger visuals or images of the whole thus fostering greater insight into the more complex natural phenomenon).

[0009] New Image Paradigm: We can often see what's at the bottom of the reductionist funnel (example: molecules), but not how these component parts rises to the top. The parametric model described herein solves this problem in a stepwise algorithm. (Step #1) Information is initially fractionated into its small individual digital (mathematical, quantifiable) components (i.e., reductionism), and each unit is "parameterized" (i.e., has quantifiable value, integer, variable, etc.); (Step #2) groups of related or interrelated units (quanta) are expressed in geometry as a volumetric image. Parametric imaging referred herein is the term applied to the acquisition of various types of quantifiable information, events or quanta, using various image techniques, and the display of surrogate information which; (Step #3) represent simple and complex anatomic, functional, hemodynamic, or physiologic events. The science of parametric imagery as described herein is totally abscent in the field of ultrasound imagery and incompletely explored in other imaging techniques such as X-ray computed tomography (CT), magnetic resonance (MR), angiography, roentgenographic images, SQUID, etc. [0010] A parameter is defined as a mathematical quantity or constant whose value varies with the circumstances. Fundamental examples of parameters include blood pressure, pulse rate, and an infinite number of other visible and non- visible events, which permeate our reality. The quantifiable event can be measured and expressed as a change over time, for example a change in pressure over time, is most often graphed or charted (e.g. a pressure curve) with the magnitude of pressure on the ordinate and time on the abscissa. However, today a sophisticated imaging device can record such events throughout a field or volume of interest (i.e., a volumetric two- or three-dimensional image of the spatial distribution of the event). Fields of specific individual or group events can then be displayed as a geometric image as opposed to a graphic or one-dimensional display of a single continuous happening. The analogy is being capable of simultaneously measuring numerous similar or dissimilar individual events and instead of graphing the result, displaying the phenomena as a dynamic geometric image (instead of looking at a single bee in a hive, the interaction of the whole hive is assessed simultaneously). To carry the analogy further one can display the action of a single bee, multiple bees of a single type, interaction of bees of different types, different hives, etc. The observed events can occur in a regular or irregular manner, distribute in a predictable or unpredictable manner, or remain constant or change randomly, etc.

[0011] Natural or physiological events are virtually always continuous or cyclical

(repetitive) but can be broken down into smaller and smaller components, which can be looked upon as quanta (i.e., elemental units) and displayed in a computer presentation as quantifiable pixels, bits, mathematical integers, etc. (i.e., this is the state of current imaging solutions). It is the elemental unit(s), which can be pictured as changing over time (i.e., time and magnitude, such as pressure or temperature). However, the whole field of units (quanta) is best presented as a distribution of base units dispersed throughout a defined spatial domain (for example, the distribution of pressure throughout a cavity of the heart or temperature of the body). The new parametric imager enables the presentation of selected quantifiable information units as a geometric picture of a continuous event. Current "fundamental image" is a mosaic of quanta and the new science of "parametric imagery" is a geometric display of specific computationally derived and segmented quanta. The parametric event becomes the image while the fundamental image or source information becomes subservient or even nonessential. At any moment in a temporal sequence, the component parts (quanta) of the parametric event can be captured as a volume with a specific quantifiable distribution. However, when it is viewed over time, the event is displayed as a moving surface, and/or volume (i.e., a two-, three-, fourth-dimensional or higher-dimensional image). Event information may include point of initiation (epicenter: for example, a thermal image of a feverish patient with an intensely "hot" pixel conclusively showing an infected epicenter as the cause of the illness), distribution (epicenter spreading outward), moment-to-moment change (evolution or wave front distribution), decay (transient, periodicity, etc.), and others. In topological language, the epicenter is called a repeller and the expanding phenomenon an attractor. An attractor, in general, is a region of space that "attracts" all nearby points as time passes. To the human senses, the imaged event may be a normally visible phenomenon such as the contracting wall of the heart (however "change" is the novel parametric and not necessarily motion), or a non-visible phenomenon (referred to as higher-dimensional events) such as the distribution of electricity, or in the case of ultrasound the derived parametric expression of electricity can be depicted as a display of novel surrogate derived information such as the sequence of successive muscle contractions. The manipulation and display of data are solved by quantum mathematical concepts. The new parametric image is a geometric image of a quantifiable phenomenon but not a mere picture of that phenomenon (for example: the motion of muscle contraction is visible, however, a parametric surrogate of contraction could be the display of change itself). The parametric image often does not appear similar to the fundamental event or image. The novel parametric presentation may have little relationship to the display of current image information.

[0012] Information: Versatility depends on having access to appropriate information and intelligence includes having access and understanding the information. If processes are to be useful, then the processing function must be fast. Herein we disclose an information process, which is applicable to medical imaging. This disclosure encompasses a novel means of capturing complex events utilizing a simple mathematical technique, which is both very fast and extremely infoπnative.

[0013] Quantum Mathematics Concept: The quantum world is a world of uncertainties and observations are inherently probabilistic — until, that is, you observe them. Generally, all physical processes are quantum-mechanical. The quantum theory of computation is an integral part of the fundamental understanding of reality. Quantum solutions applied to information, displayed as a geometric image, provide a revolutionary mode of explanation of physical reality. The human does not accord equal significance to all sensory impressions but is known to perceive reality best when presented as a four dimensional image. Thus, given the fact that general theories about nature are best expressed in quantifiable mathematical form and that geometric images are the most mature expression of a mathematical computation, it is logical that a parametric image solution will have considerable acceptance as a pleasing as well as quantifiable diagnostic imaging solution (i.e., acquisition of disparate fundamental information reassembled into an understandable multidimensional image, which is perceptibly pleasing yet quantifiable and reproducible to the human examiner).

[0014] As the trend towards faster, more compact sophisticated computer hardware continues, the technology must become even more "quantum-mechanical", simply because quantum-mechanical effects dominate in all sufficiently small systems. Each digital pixel of an image becomes a quantifiable unit (i.e., quanta) belonging to a family of events having related or meaningful characteristics. The repertoire of computations available to all existing computers is essentially the same. They differ only in their speed, memory capacity, and input-output devices. However, the yet to be developed "quantum computer" is a machine that uses uniquely quantum-mechanical effects, especially interference, to perform wholly new types of computation that would be impossible on current generations of computers. Even with today's computers such computational mathematics is a distinctively new way of looking and assessing nature. In the twentieth century, information was added to the evolution of modem computers, which has allowed complex information processing to be performed outside the human brain. However, as one enters into the twenty-first century, quantum computation is slowly being introduced, which is the next step in the evolution of information presentation (i.e., a new means of presenting and visualizing ultrasound information as discussed herein). Observations of ever smaller, subtler effects are driving ever more momentous conclusions about the nature of reality. Ever better explanations and predictions can successfully approximate visible or non-visible events, which permeate the reality.

[0015] Physiological events can be computed as distributions of comparable or related quanta (i.e., pixels of measurable information). Quantum information is not understandable unless there is a quantum-to-classical transition (a "parametric image" transformation: for example, pixels displayed as a topographic map) at which time the large quantum system loses its quantum nature. Large quantum systems generally interact strongly with their environment, causing a process of decoherence which destroys the system's quantum nature. At this time the human senses easily appreciate the natural phenomenon (the transformation of conventional image to parametric image).

[0016] Today, computers can provide integrated quantitative answers to certain otherwise unseen or unappreciated events. However, quantum events (i.e., quanta, pixels, molecules, etc. or "reductionist information") are given a position and then "spread out or imbedded" in a random volumetric distribution. Because of the unpredictability of the volumetric event, increasing computational resources must be used to measure and present the information. As all computers have some quantum characteristics, newer more sophisticated computers can actually begin to present this disparate information into a "parametric image" display revealing new physiological information. The fundamental question of the information science is then "what is the minimal quantity of physical resource required to perform the parametric information processing task?" which correlates with a natural event (for example, how much information is needed to display a segment of injured heart muscle). Quantum solutions are often used to make probabilistic predictions; however, many of the predictions can be used to predict a single, definite outcome. (Example: a geometric image of electricity or its surrogate, as described herein, can be used to accurately localize the anatomic site of an electrical excitation within the heart muscle). Quantum solutions of complexity show that there is a lot more happening in the quantum-mechanical environment than that literally meets the eye (i.e., the conventional image contains unintelligible information-^' which can only be realized when reconfigured into an understandable parametric geometric display). Quantum phenomena can be highly predictable and can foster the increasing use of computational solutions, as described herein, for the assessment of physiologic events.

[0017] Accordingly, there is a need for a computer driven acquisition device to acquire quantifiable events from today's state-of-the-art medical imaging machines to rapidly acquire physiologic information and provide images of continuously changing volumetric (spatial) information. The unique appeal of the proposed approach is to convert quantum mechanics into as a suburb means of approximating of natural events.

SUMMARY OF THE INVENTION

[0018] To overcome the natural limitations in state-of-the-art medical imaging described above, and to overcome other limitations that will become apparent upon reading and understanding the present specification, the present invention provides a general apparatus for parametric imaging of non- visible higher-dimensional events, more specifically fourth-dimensional or non- visible higher-dimensional events.

[0019] The present invention pertains to an imaging solution, using ultrasound imaging as a prime example; the imaging solution described in the present invention, however, could apply to any complex computer manipulation of acquired information. The ultrasound devices described in the present invention are those capable of rapidly acquiring finite information presented as discernable or more preferably quantifiable pixels (i.e., quanta). The acquisition elements are in multiples aligned and spaced in a manner to act in concert to obtain a field of information (i.e., a symphony of events). For example capable ultrasound transducers include linear array, curved array, vector phased array, phased array, and multi-dimensional arrays. All of these and other acquisition transducers are characterized by having multiple piezoelectric elements lying closely together and function to insonate a field and acquire underlying information. The resulting image can be a flat two-dimensional tomogram or a volumetric multi-dimensional image.

[0020] Why ultrasound—Ultrasound imaging has to date received no appreciable parametric application. Digital solutions have been slow to evolve in ultrasound imagery, as opposed to other image solutions such as radioisotopes, X-ray, or magnetic resonance. The ultrasound solution of the present invention is unique and without comparable technology and thus parametric ultrasound imagery serves as an excellent candidate to describe all the novel aspects of this imaging technique described herein. The parametric image solution of the present invention can be applied to equally unique and diverse acquisition ultrasound devices (surface transducer, catheter tipped ultrasound, esophageal, implantable and wireless transducer, etc.).

[0021] What is parametric imaging and why there is potential for confusion—The term "parametric imaging" has been used for years to apply to the general concept of using measurable information to form an image. In this general definition, one could say that any picture which has a numerical value to its contents is parametric (i.e., its component parts are parameterized). This can be further extrapolated to say that any picture which is digital, such as computerized tomography (CT), magnetic resonance (MR), nuclear isotope scans, Doppler ultrasound, etc., is parametric because some or all of the acquired information is expressed as a measurable number (i.e., pixels). The present invention herein addresses a unique parametric image solution and one that requires a higher order mathematical computer solution and is not merely a display of pixelated digital infonnation. The scientific approach disclosed herein is sometime referred to as "modeling". What models you use depend on the purposes for which you use it and the range of phenomena that you want to understand. This is where molecular imaging and clinical practice diverge. What is most interesting to the current disclosure is the practice of medicine. The system proposed is a system of features (a paradigm or worldview). Only within a chosen worldview can the human mind interpret the world. A system of features, as disclosed, is more than just a worldview, it is the creation of features of simplicity and not a complex theoretical system. The disclosure creates simple rules for the understanding of physiology. Features (parametric images) are designed for commonsense thinking and ignore the incomprehensible intricacies of unimaginably complex processes.

[0022] Firstly, the fundamental image area of interest or whole data set is broken down into its smallest quantifiable or manageable components (i.e., pixels, quanta, etc.). Currently, this exists for CT, MR, isotopes, and Doppler but does not exist for the most of the ultrasound image, conventional x-ray, etc., which are typically presented as analog pictures (classic physics). Although many conventional images are processed digitally the final image is analog and incapable of being processed into a parametric solution. [0023] Secondly, the digital components (quanta) are parameterized and measurable.

This parameterization can exist with CT, MR, and isotope images but has only recently been possible with some ultrasound information acquisition. In certain circumstances the analog components of an image have been "digitized" in an attempt to overcome this second requirement. However "digitization" significantly narrows the measurable features. There are numerous historical examples of digital or digitized information pictures, which have been called parametric. However, this is not sufficient for the present invention herein. The fundamental digital image is a display of a mosaic composed of numerous families of quanta, which are of various numerical value, size, content, etc. (example: a digital (parameterized) photograph of a flower would have numerous families of color coded digital pixels). In order to comprehend the concept of the present invention, one must go further into the computational process and segment the pixelated information, determine the minimal quantity of the physical resource required, and perform the parametric image information processing steps as claimed.

[0024] Thirdly, and importantly for the present invention, the parameterized pixels are recognized by the computer as having unique quantifiable features. Each pixel, family, data set, mathematical integer, etc. has a unique identifiable character or quantity. Pixels or computed manipulations of pixel families with similar or related features are then classified as distributions, or probabilities.

[0025] Lastly, the classified pixel features are themselves presented as a geometric picture (i.e., the information processing task, the Parametric Image Solution pertaining to the present invention).

[0026] Simple rules can be used to create a system, which in turn can create simple features (pictures, images). The development of large-scale simplicities is the direct result of rules for the management of acquired quanta. The important point about information quanta is that their presence is guaranteed, once you have set the rules of system. Thus any system with the same rules will necessarily exhibit exactly the same simple result. The concept disclosed would state that instead of dealing with quanta-to-quanta calculations which would be unacceptably time consuming, you can get away with extremely simple rales and distribute the result in geometric space (image).

[0027] "Para" refers to a substitute or replacement of reality; "metric" refers to mathematical, quantifiable; and "image" refers to a geometric picture (of a mathematically derived surrogate of reality). The resultant picture may have little similarity to the fundamental source image described in the second requirement. A new parametric image is formed which itself is a picture (geometric image) of selected quanta information. The selected information is nominally imbedded within a fundamental image. To be clinically applied such a process must occur rapidly. Sophisticated computer solutions are required to handle these complex solutions and carry out the statistical sorting of pixel features. Such parametric solutions have been suggested and may exist in some ultrasound, CT, MR and isotope imaging but are essentially experimental.

[0028] Multi-parametric and Multi-modality Imaging: The disclosure recognizes that simple parameters interact in a way that changes both and erases their dependence on the initial conditions. Component infonnation (quanta) contained within the acquired information from a single source or multiple sources can be physically or more logically mathematically combined to create a totally new set of quanta. One example would be combining segmented information for three disparate sources such as ultrasound, computerized tomography (CT) and magnetic resonance information to form a new information display. Thus totally different pieces of information can converge to produce new features, which exhibit the meaningful and/or diagnostic large-scale patterns (this concept is refened to as "complicity"). This disclosure does not imply simple super-imposition of one data set over another but the creation of a totally new data set. The concept encompasses the use of small or large components of two or more sources of information. This reinforces the concept of not merely exploring simple quanta and fixed spaces but an enlarged information management scheme. These processes collapse the underlying chaos of individual quanta and foster the production of stable features from a sea of complexity and randomness. By the nature of natural information, the behavior of quanta (the reductionist approach to "molecular imaging") is so intricate and convoluted that any attempt to dissect out its internal^' working (physiology) and causal past (diagnosis) or future (prediction of risk) history leads to a reductionist nightmare. However, the concept of parametric and multi-parametric solutions described herein allows the development of true physiological imagery.

[0029] What makes the present invention unique—Nature and its physiologic underpinnings are extremely complex. Complex phenomena continuously change in a linear or cyclical manner. Breaking such events down into small components and then expressing complexity as an understandable geometric image is extremely informative. Such images impart new information. Most importantly, such information solutions are very reproducible, more accurate than conventional measuring tools, and are quantifiable. Important prerequisites include objectivity, reproducibility, quantitation, and- multidimensional display (see: Limitation of medical images in the introduction). Although a historically familiar term, "parametric image" is used to describe the concept disclosed this new imaging paradigm. The solution described herein is completely new and has never been applied to ultrasound imaging or most of the other commonly used medical imaging systems. Nor does the solution of the present invention have any intuitive counterpart in existing comparable "imaging" modalities such as magnetic resonance, computerized tomography, or isotopes. [0030] The present invention provides an imaging apparatus having an acquisition device or parametric imager to interpret and present to the user a new geometric image of a selected parameter or derived parameters of an event acquired from an imaging apparatus. The selected parameter of an event, which can be a visible or non- visible event, is displayed in a geometric higher-dimensional image formatted distinctly different from the underlying conventional or fundamental image information.

[0031] An analogy may assist in the further understanding. The fundamental imaging device uses classical physics, which can be likened to a broadband of radio frequencies. Taken as a whole, or even as a single wavelength, the information carried by the radio frequencies is uninterruptible. (Step #1) Only when the broadband frequencies are broken down into specific channels of programs can an understandable stream of information be obtained. Likened to conventional ultrasound information. (Step #2) Beyond this, the frequencies or families of frequencies can be further sub-selected (i.e., stations or programs, themes, etc.) which impart further information (i.e., information processing). (Step #3) Lastly, the information must be corroborated with the natural event, science or rendition. [0032] In one embodiment of the present invention, an ultrasound-based parametric imaging apparatus adapted to an insonated environment. Accordingly, parametric imaging is defined herein with in terms of a unique image presentation and quantitation technique. Without the parametric solution, described herein, information parameters are found imbedded or fractionated within the fundamental image display having no separable or unique image or information display. With the claimed parametric solution, quantifiable parameters such as computed velocity, surrogate electrical phenomena, echo contrast perfusion, derived pressure, tissue velocity, strain-rate or any other constantly changing events are further separated and mathematically manipulated and ultimately displayed. The result is a new unique geometric image, which is more readily perceived and understood by a user. However even more importantly, this new science of imagery is objective, reproducible, quantitative (mathematical) and multidimensional. Accordingly, a parametric imaging apparatus of the present invention is capable of visualizing quantitative physiology and altered physiological states of the interrogated sunoundings. The parametric image is one of phenomena, which are normally too fast, too slow, or too complex to be accommodated with current imaging solutions. The new "parametric image" information is buried within the fundamental image and must be extracted as manipulated or non-manipulated families of quanta. [0033] One embodiment of a parametric ultrasound imaging solution, which is in accordance with the principles of the present invention, includes: 1) a piezoelectric state-of- the-art transducer (acquisition device), transmitting ultrasound signals to a structure proximate the transducer and receiving signals which characterized the interaction between an energy source and the intenogated tissue (physical resource); 2) a parametric image processor (computer processor) processing, partitioning at one or more selected parameter (pixel, mathematical integer, etc.); and 3) a parametric display (parametric quanta are painted onto dimensional geometry and appear as a new information image). For example the 1) fundamental event can be received as a four-dimensional event map of visible (motion, deformation, thinning, etc.) or non-visible (myocyte contraction, pressure, electricity, etc.) information; 2) the parametric processor is instructed to acquire or map a specified family of quanta from the fundamental event map; and 3) a new geometric picture of the selected parameter is created.

[0034] Dimensions: The subject of dimensions is complex and often confusing.

Three dimensions totally explain our spatial reality, which encompass height, length and width. A volumetric image, which contains three spatial dimensions, is conventionally called a three-dimensional or volumetric image. Visible motion, as described by Einstein in 1908, is designated the fourth dimension of our reality. A volumetric image, which visibly moves, is called a four-dimensional image. Our reality is, however, permeated with an infinite number of normally non-visible moving four-dimensional events (the term higher-dimensional phenomenon has been applied to non-visible events, which permeate our reality but should not be confused with theoretical physics' use of the same descriptor, which refers to parallel universes or dimensions). Examples of non-visible phenomena include heat, electricity, transformation, blood motion, flow, etc. We normally perceive these events as continuous, for example, the changing temperature of the body. The non-visible events are perceived as complex, unpredictable linear or cyclical variables. In physics, complex natural events have been discussed under the headings of chaos, fractals, fuzzy logic, quantum mechanics, etc. All of these disciplines are based on the fact that immense predictability of complex chaotic systems can be obtained from less than absolute solutions. By breaking a complex event into quantifiable (i.e., parameterized) components and then presenting the event as a probability distribution in an image format is extremely enlightening and a novel means of imaging physiological events. The parametric image described herein presents visible and non- visible events as geometric pictures, thus brings an otherwise complex event into an understandable visible and quantifiable reality. The technique requires sophisticated computer management of information, which results in extremely reproducible, quantifiable information. A higher-dimensional event displayed in a static two-dimensional display results in a 3-dimensional image. A human can best appreciate higher-dimensional phenomena when the event or its surrogate is distributed in a 3- or 4-dimensional display. Because higher- dimensional events are too fast or too slow to be appreciated by conventional imagery the event or its surrogate must be reassembled in a temporal and spatial domain consistent with the human perception. The one of the basic functions of a parametric solution is the display of higher-dimensional infonnation.

[0035] Other embodiments of an ultrasound imaging apparatus in accordance with the principles of the invention may include alternative or optional additional aspects. One such aspect of the present invention, as it pertains to ultrasound, is that the transducer is a piezoelectric ultrasound-based transducer. The piezoelectric transducer is the component, which acquires information. The configuration of the transducer can be in a variety of formats. The ultrasound transducer configuration (format) can be of any form as described herein and acquires parameterized information in a two-, three-, four-, or a higher dimensional image presentation. For example, the transducer can be a group of transducer elements or an array of transducer elements. Also, the type or operation type of the ultrasound-based transducer can be in a variety of formats. For example, the transducer can be an offset stereoscopic imaging ultrasound transducer array, a sector array, a linear array, a linear phase array, a phase linear array, a curved phase array, vector array, etc. The ultrasound transducer can be comprised of small or large numbers of piezoelectric elements in a single array or in multiple arrays or any piezoelectric material (crystal or polymer). Each array may be a one-dimensiόnal array, a one-and- one-half-dimensional rectangular array, a two-dimensional square array, a matrix of closely spaced and aligned individual elements, or an offset array comprised of multiple arrays grouped together to provide a variance in perspective. Other imaging modalities are also characterized by a diverse number of acquisition solutions and devices.

[0036] Another aspect of the present invention is that the selected quantifiable parameter is of often a surrogate of a phenomenon. Events such as blood flow velocity, perfusion, pressure, contractility, image features, electricity, metabolism, transformation, and a vast number of other constantly changing visible and non-visible parameters are brought into the realm of visual reality. However, the event itself (i.e., electricity, contrast, tracer, microvascular flow, etc.) may not necessarily directly visualized. Instead, the acquisition device produces a surrogate parameter, which can best predicts and parametrically displays an event (for example electrical depolarization/repolarization of the myocardium may . be represented by a surrogate quanta such as the sequential contraction of electrically excited myocytes).

[0037] Parametric Imaging is an old term, however, in the context described herein, the application is totally different. Historically, a digital imaging system such as magnetic resonance, nuclear radioisotopes, x-ray, and computerized tomography have been used to acquire pixelated "parametric" information. Ultrasound has until recently not accommodated digital solutions. Thus the mere parametric digitization and display of information as claimed is not comparable to the current claim of a new novel parametric image solution. The term parametric imaging as disclosed herein has not been applied to the state-of-the-art imaging devices (for example ultrasound imagery). The unique aspect of the present invention is the extraction of parametric information from the fundamental image and reformatting this new information into a new geometric or parametric image. [0038] In one aspect of the present invention, the invention is unique in that it is an ultrasound system, which is a new geometric parametric event imager.

[0039] Using an ultrasound apparatus and the concept of quantum computation, families of physiologic events can be described by geometrically expressing surrogate features. This presentation assists in explaining such events, and ultimately describing why something happens by invoking the flow of time. Quantum descriptions of distributions resolve events into measurable units of simplicity and comprehensibility and can be looked upon a high-level simplicity derived from low-level complexity. The sunogates of physiologic phenomena can be displayed as easily understood geometric images suited to the human's four-dimensional comprehension of reality.

[0040] Accordingly, the present invention provides a geometric image for an objective result of an event. Such an event is reproducible. One obtains the same result each and every time if provided initial comparable parameters. The present invention provides a capability of placing a numerical result into a measurable scheme. Further, the present invention has a capacity to expand as a spatial distribution in surface, area, and volume. [0041] A new science of imaging: the emphasis is on qualitative geometric images, which are mathematically reproducible and measurable (i.e., quantifiable). The organism does not see quanta but only those features that produce a particular effect (for example a heart attack is the feature and the dying myocyte the quantum expression). Each natural system reacts with expressed features. The unique disclosure herein proposes a means of how to understand the geographies of spaces and how they conspire to create new patterns and combined dynamics. The generated features are treated in a precise way, unlike the current qualitative meteorology. The computer generated runs logical programs that allow the generation of understandable large-scale features, rather than allowing "quantum information" to emerge as a by-product of billions of bits of information. We claim that this is where the science of imaging is headed. This concept places more emphasis on questions such as structure and development (i.e., contraction, function, transformation, etc.), so the science can combine internals and externals into single, coherent schemes ("the parametric image"). [0042] These and various other advantages and features of novelty, which characterize the invention, are particularity pointed out in the claims annexed hereto and forming a part hereof. However, for a better understanding of the invention, its advantages and objectives obtained by its use, reference should be made to the drawings which form a further part hereof, and to the accompanying descriptive matter, in which there is illustrated and described one preferred embodiment of the invention. Although ultrasound is discussed in detail, other imaging modalities would also be enhanced and affected by the novel innovation described.

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] A better understanding of the construction and operational characteristics of a preferred embodiment(s) can be realized from a reading of the following detailed description, especially in light of the accompanying drawings in which like reference numerals in the several views generally refer to conesponding parts.

[0044] FIG. 1 is a block diagram illustrating one embodiment of the parametric imaging apparatus in accordance with the principles of the present invention.

[0045] FIG. 2 is a cross-sectional view of one embodiment of a parametric imaging apparatus taken proximate a distal end showing an ultrasonic transducer and a generic therapeutic device extended within a field of view.

[0046] FIG. 3 is an image display of a segment of left ventricular myocardium using a phased array ultrasound imaging transducer without applying a parametric image solution.

[0047] FIG. 4 is an image display of a velocity mode of the segment of left ventricular myocardial (i.e., the parameter is the velocity and is displayed as a surrogate of electricity and the depolarization/contraction of the insonated myocardium) using a phased array ultrasound imaging device applying the parametric image solution in accordance with the principles of the present invention to visualize the epicenter of the electrical stimulus.

[0048] FIG. 5 is a schematic view of one example of presentation and display of radio frequency (RF) signals in a parametric imaging process in accordance with the principles of the present invention.

[0049] FIG. 6 is a schematic view of one example of acquisition of transducer received signals and formation of the RF signals in the parametric imaging process in accordance with the principles of the present invention. [0050] FIG. 7 is a schematic view of a parametric imaging catheter apparatus in accordance with the principles of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0051] In the following description of the exemplary embodiment, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration the specific embodiment in which the invention may be practiced. It is to be understood that other embodiments may be utilized as structural changes may be made without departing from the scope of the present invention.

[0052] The present invention provides an imaging apparatus having an acquisition device (transducer and ultrasound machine) and a parametric imager (computer processor), which interprets and presents an acquired event(s). The selected parameter(s) can be a visible or non- visible quantifiable temporal event(s), which can be displayed as a unique geometric parametric image.

[0053] In one embodiment of the present invention, an ultrasound-based parametric imaging apparatus adapted for an ultrasound environment is described by way of example. Accordingly, parametric imaging is defined herein as a type of geometric image presentation and quantitation. Without the parametric solution, parameters (quanta) are embedded and presented as a part of a fundamental image and are not separated temporally or geometrically from their surroundings. With the parametric solution, parameterized information such as velocity, strain, pressure, motion, change or computed surrogate information such as electricity, amplitude, coherence, distortion, etc., can be recorded as a static or constantly changing quantifiable events (pixels mapped to volumetric geometry) and expressed as a new unique geometric image. As a result, physiologic (reality) events can be more readily perceived and understood and quantified. Accordingly, a parametric imaging apparatus of the present invention is capable of quantitatively visualizing novel depictions of dynamic physiologic events and altered states within the intenogated surroundings. [0054] The prefix "para" of the term "parametric" refers to something, which represents some naturally occurring phenomenon, which may or may not look like the original. "Parametric" is defined herein as a quantifiable metric expression of a naturally occurring phenomenon. "Parametric imaging" is a geometric image of the distribution of a quantifiable physical resource (pixel, mathematical integer, etc.). [0055] In one embodiment of the present invention, the imaging systems used includes information acquisition ultrasound transducers generally comprised of arrays of elements (e.g. linear, phased, multi-dimensional, etc. arrays) or a single element rotated or translated to produce a tomographic 2-dimensional field of view in an azmuthal plane. Typical ultrasound anays may include: 1) a linear array (linear sequential anay), usually producing a rectangular or rhomboidal tomographic picture; 2) a cylindrical array or rotating crystal, producing a round pie-shaped tomographic cut; 3) a sector array (linear curved or vector phased anay), producing a triangular shaped tomographic image; 4) multi-dimensional arrays (one-, one and one-half, and two-dimensional), which acquire multi-dimensional information; 5) off-set transducers, which obtain stereoscopic infonnation, etc. Images from these transducers can be tomographic and/or focused both in the azmuthal and elevation planes. Many transducer configurations produce a thin ultrasound cut of the insonated structures, which by nature is usually thin and of high resolution.

[0056] A more sophisticated ultrasound imaging solution includes transducers, which obtain volumetric images. Two general techniques are utilized to obtain three-dimensional spatial infonnation. The first utilizes the tomographic two-dimensional imaging array and fuses the information obtained from multiple spatially aligned two-dimensional images. The second technique obtains an instantaneous volumetric image with the use of two-dimensional piezoelectric element arrays (i.e., multiple rows of elements). A volumetric imager simultaneously obtains information in all three spatial dimensions. A parametric solution (i.e., distribution of quantifiable information) can be extrapolated from the fundamental information contained within the two-dimensional spatial domain or a three-dimensional domain. Both solutions are germane to the present invention, each having certain applications and in certain circumstances an advantage over the other. [0057] FIG. 1 illustrates one embodiment of a parametric imaging apparatus in accordance with the principles of the invention. As described, various types ultrasonic transducers or transducer anays can be used in the present invention, such as mechanical and dynamic one- and two-dimensional transducer arrays. A phased array ultrasonic transducer 28 which is used to transmit ultrasound and acquire resultant echo information such as Doppler flow, tissue Doppler, color Doppler, harmonics, pulse inversion, feature extraction or characterization, strain, strain-rate, acceleration Doppler, power Doppler, etc. and the physiological reality they represent. Images can be two-dimensional or multidimensional and present tomographic, volumetric, stereoscopic, or virtual information. The information obtained in any of these manners can be subjected to parameterization and be processed into a parametric image solution.

[0058] Referring now to FIG. 2, the ultrasonic transducer 28 can be a piezoelectric material such as a ceramic crystal or polymer, such as Polyvinylidenedifloride (PVDF) 34, which is bonded by an epoxy layer 36 to a depression 38 approximate the distal end 26. Although some details are provided with respect to an embodiment of an ultrasonic transducer which might be used, it will be appreciated that various types of transducers or transducer arrays having various configurations and orientations may be utilized to obtain parametric information without departing from the principles of the present invention. Other imaging modalities would use different acquisition techniques and energy sources. The parametric imaging apparatus illustrated is disclosed more fully in U.S. Patents Nos. 5,325,860, 5,699,805, 5,704,361, 6,039,693, 6,099,475, 6,129,672, 6,306,096 and 6,398,736, 6,544, 187 the disclosures of which are incorporated herein by reference. [0059] Phenomena observed or so created can be subjected to the parametric information acquisition, computer processing and geometric display.

[0060] In FIG. 3, includes an appropriate control circuitry 32 for controlling operation of the ultrasonic transducer 28. The control circuitry 32 is electrically interconnected to a transceiver circuitry 48 (T/R) for Transmitting and Receiving signals via a cable 50 to and from the ultrasonic transducer 28. hi turn, the transceiver circuitry 48 is electrically interconnected to a Doppler circuitry 52 and an appropriate display device 54 for displaying hemodynamics or blood flow, etc. In addition, the transceiver circuitry 48 is electrically interconnected to a suitable imaging circuitry 56, which is interconnected to a display 58 for displaying images. Other information acquisition and transmission solutions would include wireless technology.

[0061] During operation, the control circuitry 32 may be designed to cause ultrasonic transducer 28 to vibrate. The ultrasound wave, represented by line 60 in FIG. 2, will propagate through the fluid, e.g. blood, body fluid, or tissue subjacent to the transducer 28. A portion of the ultrasound wave so transmitted will be reflected back from both the moving structures such as valves and red blood cells, as well as from insonated structures to impinge on the transducer 28. Because of the piezoelectric nature of the transducer, an electrical signal is thereby generated and transmitted by the cable 50 or wirelessly to the input of transceiver 48. A signal may then be variably transmitted to the Doppler circuitry 52 which may use a conventional amplifying and filtering circuitry commonly used in Doppler flow metering equipment. The Doppler circuitry 52 analyzes the Doppler shift between the transmitted frequency and the receive frequency to thereby derive an output proportional to velocity or other phenomena. This output may then be displayed at the display 54. The display 54 may be a suitable analog or digital display terminal. Accordingly, the user will be able to obtain an image or numerical value of velocity, blood rates and hemodynamic or physiologic information.

[0062] In order to acquire fundamental image information, the control circuitry 32 triggers ultrasonic transducer 28 via the transceiver 48 to vibrate and produce an ultrasound wave. Once again, a portion of the wave or energy will be reflected back to the ultrasonic transducer 28 by the insonated features. A conesponding signal will then be sent by the cable 50 or wirelessly to the transceiver circuitry 48. A conesponding signal is then sent to the imaging circuitry 56 which will analyze the incoming signal to provide to the display 58. The display 58 may be any type of suitable display apparatus for displaying an image (fundamental or parametric) of the insonated features.

[0063] The imaging can occur at anytime even while a therapeutic or surgical device is within the field of view provided by the ultrasonic transducer 28. Accordingly, the user will be able to visualize actions and the result thereof.

[0064] Also in FIG. 1, parametric information can be obtained or generated in numerous places in the acquisition circuitry. One can use the Doppler information from the Doppler Circuitry 52 and create parametric information and image via a parametric imager 68. This can be analog or digital information but considerably far down the image processing cascade and image circuitry. One can also create parametric information and geometric images with a parametric imager 70 off of the imaging circuitry 56. This would include display of motion and gross anatomic information. A more mature parametric solution and image via a parametric imager 72 or 84 can be obtained from radio frequency (RF) data taken off of the beam former 76. The parametric information and resulting images at imager 72 is created by received data from the transducer 28 and is taken off very early in the image processing cascade, for example, just after the beam former 76. The digital information or data 78 is presented as parameterized image pixels of quantifiable information. The distribution of features (i.e., surrogate families of pixel quanta) can be displayed 90 as the parametric image. Similarly, parametric information and image can be generated further along the imaging process chain, for example, after performing a scan conversion 80 and generating a digital data set 82. The digital data set 82 is used to generate a parametric image via a parametric imager 84. Accordingly, parametric imaging is a particular data processing solution that looks at distributions of parameterized events and presents those real or mathematically derived distributions as a quantifiable geometric image. A parametric image can be a distribution of an image feature, a distribution of Doppler phenomena, a distribution of parameterized digital data pixels, or a distribution of post-scan conversion display information.

[0065] Parametric imaging is defined as the imaging of "parameters" which are visible two-dimensional, three-dimensional, fourth-dimensional, or non- visible higher-dimensional temporal events. Visible fourth-dimensional events include features such as cardiac contraction, valve leaflet motion, dynamic features, etc. Non- visible motion may include slow non-visible events (i.e., remodeling, aging, healing, etc.) or fast non-visible events (i.e., contractility, electricity, strain, strain rate, compliance, perfusion, etc.) Parametric imaging requires: 1) an acquisition device (i.e., ultrasound machine and transducer) which obtains rapidly or temporally sequenced acquired analog, digitized, or digital information of the physical resource such as Doppler, strain rate, etc., and expresses the information as pixels, mathematical integers, bits, quanta, etc.; 2) a state-of-the-art "information" computer processor (quantum mechanical solutions) which identifies the information processing task using the physical resources collected (for example, compressing the output from an information resource into a bit string and then decompressing the bit string to recover the original information as an image from the geometric display of the compressed output). A geometric presentation of the parameterized information is obtained; and 3) a quantitative interactive display. The created image is also confirmed by verifying the output from the decompression stage with the input from the compression stage. It is appreciated that various types of acquisition techniques can be used. The techniques vary in sophistication (anatomic to digital pixel parameterization), modality (image, Doppler, phenomena etc.), information (analog, digitized, digital), and purpose (aging which is a slow event recording; electricity which is a very rapid non- visible event; contractility which is a visible motion event). Specific examples of the applications will be discussed below.

[0066] A parametric imager selects one or more features of an event and generates an image, which is a quantifiable geometric sunogate of a visible or non- visible event, which is validated as a comprehensible event. Quantified distributions of parameters represent a new and unique means to appreciate phenomena such as dynamic physiology. Accordingly, a parametric imaging empowered ultrasound device or comparable imaging technology (magnetic resonance, computerized tomography, nuclear radioisotope, SQUID, etc.), in addition to conventional imaging solutions, function, dynamic flow and hemodynamics, can obtain dynamic quantifiable features extracted from such information. The insonated environment information is presented as static or dynamic geometric figures, which contain additional enhanced discrete or gross quantifiable information. [0067] A parametric image is an image that is created by acquiring or creating parameterized information, which can be gross features, mathematical derivatives, or fractionated discrete elements, such as pixels. The features or elements are parameterized (i.e., numerically weighed) and looked upon as quanta. The parameterized features or elements have distinguishing magnitudes or mathematically derived values. Groups of units (quanta or pixels or characteristic elements) are typically continuously changing both in value and spatial distribution.

[0068] Any evolving or spreading phenomenon has a spatial distribution and volume and includes a sequence of changing geometric moments or "snapshots" of itself. The instantaneous "snapshots" or versions of an event collectively are perceived as a continuous and moving phenomenon (i.e., heat) or object (i.e., magnitude of the heart's contraction). Any moving or changing phenomenon is thus capable of being depicted as a sequence of geometric moments. Sophisticated computer acquisition devices can be configured to rapidly acquire dynamic physiologic information. The ultimate device is a form of quantum computation (based on computational probability). The sunogate families of features are geometrically displayed. Thus, such events are visually and quantitatively explained, and ultimately describe why something happened by invoking the flow of time. Quantum descriptions of distributions resolve events into measurable units of simplicity and comprehensibility, which can be looked upon as high-level simplicity derived from low-level complexity.

[0069] Described below are a few general examples of parametric images, which can be obtained with the an imaging device (example ultrasound imager). These examples represent only a sampling of an infinite anay of parametric solutions. The present invention provides an imaging device empowered with parametric solutions described herein. Parametric imagery is equated with the geometric (i.e., volumetric) display of physiologic events which is particularly unique and suited to ultrasound but can be applied to any device capable of obtaining physical resources. It is appreciated that the utilization and understanding of multidimensional quantifiable distribution of parametric events have important clinical utility and implications.

[0070] EXAMPLES: Examples of multidimensional medical parametric imaging are described below, whereby visible or non- visible motion is recorded and quantified, and events mathematically expressed in numerous ways, depending on the clinical purposes. Parametric solutions are a unique introduction to ultrasound yet not necessarily obligated to a particular acquisition modality. The parametric display of many events requires mathematical manipulation of the fundamental information into new quanta and consequently the parametric geometric display (image) can have little relationship to the original fundamental image information.

[0071] 1) Change or Transformation: Nonnal and abnormal physiologic events which occur over time can be as slow as aging and remodeling or as rapid as the heart's myocardial contraction. Although one can perceive the evolution of the actual event, one cannot capture prolonged or instantaneous change as a separate phenomenon. At any moment in time, the phenomenon's change is so minute or transient that it cannot be separated as a distinct happening. The human senses perceive such events only as linear or cyclical continua. However, the computer is used to change or transform and express this phenomenon as a sequence of geometric moments. Change or transformation information is presented in a number of meaningful ways. For example, the volumetric excursion of a surface is presented as a geometric picture and measured as expression of the magnitude of change. The phenomenon change is expressed as an image and not the physical motion such as a wall contraction. In this circumstance, excursion is itself and not the wall surface, and motion is expressed as a volumetric expression of that which has changed or transformed. [0072] Unique to the expression of parametric images of the present invention is the manner in which the phenomenon is expressed. For example, electrical events are expressed as the instantaneous and sequential contraction of muscle fibers, transformation as a volumetric expression of that which has expanded or contracted or the mass which has changed, perfusion as a feature of the insonated milieu, pressure as Doppler frequency shift, and metabolism as alterations in stiffness, etc. In each instance, the parametric solution is very much different from that described by CT, MR, or nuclear for that fact in any previous science. Further, the manner of display is uniquely differentiated. The phenomenon is displayed in preference or deference to the fundamental information or image. The parametric phenomenon becomes the primary visible and quantifiable result. The resultant images, which are an expression of the event but not the structure, may have little resemblance to the original structure but will contain qualitative (visual) and quantifiable (mathematical) information important to the better understanding of the event. [0073] 2) Flow: The continuous movement of gas or liquid is normally invisible because of the rapidity of the event and the invisible nature of the perfusate. New contrast agents and image solutions create a unique opportunity for the parametric solution. New tracers produce novel mathematical opportunities for parametric display. Extraction of a tracer or its interaction with the sunounding environment can be used to produce a new parametric display, which is uniquely reproducible and quantifiable. For example Doppler ultrasound can display blood flow as a shift in ultrasound frequency and displayed as a distribution event. Parametric expressions of flow capture multiple parameterized morphological and physiological phenomena, such as: 1) the space in which the event occurs, 2) the actual three-dimensional distribution of the event within the space, and 3) quantifiable physiology of the fluid, such as velocity, viscosity, turbulence, etc. Parametric imaging takes an advantage of unique and powerful attributes of simultaneous visualization of quantifiable features, pixels, as well as the visualization of multiple phenomena (multi-parametric image) or information from multiple technologies (i.e., multi-modality parametric image). [0074] 3) Perfusion: A parametric image of perfusion can be expressed as a distribution of feature changes caused by the interaction of between the energy source and a blood tracer such as spheres of gas or alternatively isotopes, magnetic fields, etc. Parametric information can be captured as a quantifiable two- or three-dimensional surrogate of the distribution of the perfusate. A multi-parametric display of multiple simultaneous events, such as function (transformation) and perfusion, simultaneously is possible. The quantitative distribution of feature, such as flow velocity, can be utilized as an expression of the magnitude of a perfusion/function defect or burden.

[0075] 4) Pressure: Pressure can be perceived but not visualized without enhancement. The multi-dimensional display of pressure (i.e., volumetric distribution of quantifiable features or families of parameterized pixels)' which is otherwise non-visible phenomena, can be displayed in a visible multi-dimensional format, hi the new imaging paradigm, instantaneous pressure, such as recorded by ultrasound Doppler velocity shift, can be displayed as a multi-dimensional distribution. A sunogate of a dynamic pressure map better highlights regional and global physiological dynamics. The uniqueness of the parametric solution is the volumetric display of quantifiable physiology. Pressure itself becomes the picture.

[0076] 5) Contractility: Distribution of velocity, force, and traction parameters, such as fractional shortening, and distribution of contractile phenomena, can be displayed in a volumetric parametric image. The parameterized phenomena and not the usual ultrasound signal, is presented as the primary quantitative image. A volumetric image of events such as Tissue Velocity Image (TVI), motion and muscle contraction are displayed as a geometric parametric image. Normal and abnormal cardiac muscle function can be presented in a quantifiable image. . The parametric solution frequently has little resemblance to the fundamental information but imparts greater information content when presented as a quantifiable parametric volumetric image.

[0077] 6) Image Features: Tissue texture metrics (i.e., features) can be assessed in many ways. The parametric imaging solution can elucidate dynamic tissue histopathology. When displayed as a higher-dimensional parametric image, normal and abnormal tissue can be separated from its sunoundings. Feature extraction is a quantum statistical technique, which can analyze the large volume of tissue. The parametric image can be used to create a new image represented by one or more embedded tissue characteristics. This parametric image is unique to the particular individual imaging solutions such as the under-fluid catheter imaging, implantable ultrasound transducers or ultra-high resolution images. [0078] 7) Electricity: Electrical forces are invisible events to most imaging solutions including ultrasound. However, surrogate phenomena can be detected and displayed as surrogate representations of electricity (for example, ultrasound tissue Doppler imaging velocity or tissue acceleration can be displayed as parameterized as a sequence of myocardial muscle contraction coincident with electrical depolarization and repolarization). When sequential muscle contraction processed into a parametric map and displayed as a volumetric image, a sunogate image of electrical activation is created. Visualization of the sequential polarization and depolarization allows quantitation of normal and abnormal electrophysiologic events. Such a parametric solution can be used to direct therapy of arrhythmias as cunently practiced in an electrophysiologic laboratory. Quantifiable alterations of the geometry of the electrical field would have therapeutic implications. This particular parametric solution is unique to the under-fluid ultrasound systems but can also be replicated with other parametric imaging acquisition technologies.

[0079] 8) Metabolism: Metabolic activity and change of underlying function are not normally visible to the normal human senses. However, through higher-dimensional acquisition and display of ultrasound information, metabolic activity can be modeled, to accurately depict, and most importantly express this information as distributions of variable metabolic activity (i.e., myocardial injury, death, or hibernation).

[0080] 9) Others: It is appreciated that there are an infinite number of higher- dimensional parametric ultrasound solutions utilizing various acquisition devices. [0081] As an example, FIG. 3 shows an image display of a segment of left ventricular myocardium using a phased anay ultrasound imaging catheter without applying a parametric solution and represents the fundamental image. The frequency of the transducer is 7.5 MHz and the diameter of the catheter body is 10 French (3.2 mm diameter) (one French divided by Pi equals one millimeter (mm)). FIG. 6 shows the same myocardium displayed as a parametric myocardial velocity map. Each pixel and family of like velocity pixels appear as concentric contraction wave. Parameterized features include velocity, distribution, volume, and variable concentric waves of contraction velocity. The ultrasound catheter is used for parametric imaging in accordance with the principles of the present invention. As shown in FIG. 4, the myocardial segment is imaged with parametric tissue Doppler (TD) at a frame rate of >= 100 frames per second and reformatted to a temporal sequence which is more familiar to the human reality (i.e., static or visible wavelets of sunogate electrical phenomenon). Using the velocity mode of TD, regional myocardial contraction is parameterized to equate to an electrical event (i.e., the ultrasound visualization of electricity using sunogate parametric pictures of tissue acceleration velocity). Each segment of muscle is given a color based on recorded regional pixel velocity. Each pixel has a specific value related to velocity; all similar velocities have a similar color. As shown, the initial and now slowing velocity is the epicenter of the electrical stimulus (bright green). The contractile velocity spreads outward in wavelets from the epicenter, velocities spread outward like waves in a pond with each wavelet having a similar instantaneous velocity (orange, deep red, blue). The initial point of electrical excitation is visually and quantifiably localized to the point of the initial muscle contraction. Propagation of the parameterized electrical surrogate is the realistically and quantitatively assessed. As shown in FIG. 4, the image is a two-dimensional sunogate display designed to show an electrical epicenter. The parameterized phenomenon is multidimensional (two spatial dimensions and one higher-dimension of change), which distributes kregularly. Other multidimensional displays of electrical events are intuitive and would be designed to answer specific physiologic questions.

[0082] FIG. 5 illustrates a schematic view of one example of presentation and display of radio frequency (RF) signals in a parametric imaging process in accordance with the principles of the present invention. The RF signals are parameterized and presented as quantifiable pixels of image information. The pixels are then summed to form a fundamental picture or image. The parameterized pixels contain mathematical features of families of pixels, which can be separated into meaningful parametric distributions and displayed as a new geometric image. These new images can be presented as geometric moments or dynamic cyclical or continuous events. The new image often does not appear like the fundamental image or have an intuitively familiar analogy or analog. However, the new image is a simple quantifiable geometric figure of an otherwise complex event. [0083] FIG. 6 is a schematic view of one example of a sophisticated acquisition device using radio-frequency (RF) signals which are parameterized in accordance with the principle of the present invention. The RF signals are the output of the beam former 76 (FIG. 2). Received signals from and ultrasound transducer are amplified (e.g. analog gain) to ensure the optimal use of the dynamic range of the analog-to-digital (A D) converters. The analog gain factor varies according to the distance the received signals travel into the insonated tissues, i.e., deep signals are amplified more. The signals are then delayed individually to focus the beam to account for certain depth and direction. The delayed signals are weighed to obtain the desired apodization and beam profile. The weighed and delayed signals are summed in phase to result in RF signals. The RF signals are digital, thus are more easily parameterized, and thus are most suited to the parametric solution. [0084] FIG. 7 illustrates a schematic view (essential three steps of a parametric solution) of one example of parametric imaging apparatus in accordance with the principles of the present invention. The transmitter 48 sends signals to the ultrasound transducer 28 which transmits signals to a structure and in turn receives echo signals from the structure. The received signals are then sent to the receiver 48 to be processed in the processing device 88 (FIG. 2) and to be displayed by a display device 90. It is appreciated that the processing device 88 may also incorporate a processing device 86 as shown in FIG. 2 to obtain parametric imagers from the ultrasound Doppler circuitry 52 and/or imaging circuitry 56. A parametric display is derived from the fundamental image information (physical resource step 1). The physical resource is represented as multiple variable bits, pixels, quanta, etc. Step 2 identifies an information-processing task. Step 2 compresses the resource information into families or features with individual or multi-characteristics, and then displays this decompressed information as a geometric distribution of select parameter(s). Step 3 is an internal or external validation process of the compression-decompression of task 2. Task 3 determines the criteria for acceptance and assures a match between the decompressed and compressed data.

[0085] It is appreciated that the configuration and anangement of the acquisition device may vary within the scope and spirit of the present invention. The present invention deals with the use of parametric imaging in order to uniquely assess dynamic natural events such as physiology. The parametric imaging apparatus of the present invention is capable of visualizing visible as well as very fast or very slow non- visible motion events and is capable of creating measurable geometric surrogate representations of physiology, including transformation, blood flow velocity, perfusion, pressure, contractility, image features, electricity, metabolism, and a vast number of other constantly changing parameters. Parametric solutions have not been applied to ultrasound systems but is equally applicable to other image acquisition devices including computerized tomography (CT), magnetic resonance (MR), etc. The parametric invention allows presentation of physiologic phenomena as geometric images temporally and realistically reformatted to the human's two-, three-, and four-dimensional comprehension of reality.

[0086] It is also appreciated that the transducer 28 may have variable configurations and anangements, such as longitudinal, toroidal (longitudinal rotation), forward-and-side viewing, volumetric (3 -Dimensional viewing), mechanically rotating element(s), etc. The concept of a parametric solution can also be applied to other acquisition devices including MRI, CT, nuclear radioisotope, SQUID, etc.

[0087] It is further appreciated that the ultrasound device may have full Doppler capabilities which includes pulsed and continuous wave Doppler, color flow Doppler, tissue Doppler (velocity, acceleration, and power modes), strain-rate, strain, etc. [0088] The present invention pertains to the incorporation of a unique imaging solution (parametric imaging) into virtually any ultrasound device or configuration. Parametric imaging is an evolving concept based on an evolving technology empowered by increasingly sophisticated computer management of acquired information. For the purposes of this imaging technique, information is broken down into measurable features or into small measurable components and likened to quanta (i.e., elemental units). Parameterization requires a digital or digitized image presentation (i.e., an image comprised of mathematically measurable components). The change over time of the elemental feature or unit can be measured (i.e., velocity, strain-rate, etc.). Features and/or units, on a larger scale, are envisioned as having definable meaningful characteristics, which when presented as a group, are interpreted as a sunogate of a physiological event, such as: (infarct, perfusion, electricity, transformation, etc.). An event can be defined as having a measurable distribution (i.e., volume, mass, surface), as well as a variable mathematical value of the constant constituent pixels (i.e., quanta). The distribution of the event is typically unpredictable and inegular and best defined by a multi-dimensional image presentation (i.e., more meaningful and understandable to the observer as the dimensional presentation increases from a two- to three- to four-dimensional presentation). The incorporation of a parametric solution into an ultrasound device does not exclusively foster the visualization and quantitation of physiologic and feature characteristics of the insonated volume. The fundamental characteristics of an ultrasound device are retained, however parametric imaging will add a new and novel means of obtaining physiological information.

[0089] The computer interfaced image processing may include the use of any quantifiable acquisition technique including: hannonics, Doppler, pulse inversion, etc., which capture motion as discrete quantifiable local events or distributions of events. One of the unique aspects of the present invention is the display of that information and not the specific acquisition transducer or information acquisition algorithm. [0090] The computer-interfaced image processing optimally includes the capture of motion (fourth- and higher-dimensional events). The examples of physiologic motion are as follows: fast invisible motion (i.e., higher-dimensional information, for example, electricity, strain, elasticity, pressure, force, perfusion, etc.); slow invisible motion (i.e., higher- dimensional information, for example, aging, remodeling, transformation, etc.); and visible motion (i.e., fourth-dimension, for example, contractility, translated motion, valve motion, etc.). One unique aspect of the present invention is the assessment of these events by the use of surrogate information presented as quantifiable units (pixels, quanta) and displayed as quantifiable spatial distributions (surface, area, volume). For example, fast invisible electrical events are in one embodiment displayed as tissue Doppler acceleration and the temporal and spatial distribution of that sunogate event; slow invisible motion of remodeling is displayed as a geometric distribution of the phenomenon of quantifiable change while tissue itself is not displayed subservient to the image; and the visible motion of contractility displayed as quantifiable volumetric excursion.

[0091] The computer interfaced image processing further includes the captured otherwise invisible features (i.e., feature extraction). The examples are as follows: microanatomy including fibrosis, edema, infarction, etc., and perfusion including microcirculation (echo contrast, Doppler blood cell tracking, target tracking, etc.). It is acknowledged that the particular acquisition technique, expressed mathematical events, particular phenomenon recorded are merely exemplary of the present invention. In general, the present invention relates to a new quantifiable image solution (i.e., parametric imaging) applied specifically yet not exclusively to any information acquisition device. Ultrasound is used as an example (transthoracic, transesophageal, catheter, etc.) used for surface, underblood or fluid application.

[0092] The geometric presentation of physiologic events includes: a) Distribution of quanta: motion events are presented as quantifiable distributions; b) Scalable dimensions: one-dimensional, two-dimensional, three-dimensional, four-dimensional and higher- dimensional presentations. (Higher-dimensional events are invisible to the human senses and are normally perceived as continuous events, e.g., temperature, electricity, aging, etc.). [0093] The quantum mathematics and quantum computing includes: a) Mathematics of quanta, examples of quanta include electricity, pressure, sound; b) Quantum math where location and velocity typically cannot be computed simultaneously; c) Geometric presentation of physiologic events and otherwise unseen features; and d) the use of probability theory (fractal geometry, chaos, fuzzy logic, mathematics which presents highly accurate predictions of natural events). The key to understanding complex interactions of natural physiological events is not a network of complex parameters but the interaction of features (i.e., quanta) with different geometric spaces, which best express reality. [0094] It is to be understood that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

Claims

WHAT IS CLAIMED IS:

1. An acquisition device capable of parametric imaging of an intenogated structure, the device comprising: a device for receiving physical resource signals which contain an event of at least one selected parameter; and a parametric imager configured and adapted to process the physical resource signals and presenting at least one selected parameter as an event image, the event capable of being a non- visible multi-dimensional event which is non- visible to a human user's eye prior to the processing by the parametric imager; wherein the parametric imager is configured and adapted to process the signals to RF signals, the RF signals being digital signals and parameterized to present at least one selected parameter of the event in the image.

2. The acquisition device of claim 1 , wherein the image is a two-dimensional image.

3. The acquisition device of claim 1, wherein the image is a three-dimensional image.

4. The acquisition device of claim 1, wherein the image is a fourth-dimensional image.

5. The acquisition device of claim 1, wherein the image is a higher-than-fourth- dimensional image.

6. An information gathering device capable of parametric imaging, the device comprising: a receiver disposed to acquire physical resource information containing at least one data set of selected parameters; and a parametric imager configured and adapted to process the signals and presenting at least one selected parameter of the event as an image, the event capable of being a non- visible multi-dimensional event which is non- visible to a human user's eye prior to the processing by the parametric imager; wherein the parametric imager is configured and adapted to process the signals to RF signals, the RF signals being digital signals and parameterized to present at least one selected parameter of the event in the image.

7. The information gathering device of claim 6, wherein the image is a two- dimensional image.

8. The information gathering device of claim 6, wherein the image is a three- dimensional image.

9. The information gathering device of claim 6, wherein the image is a fourth- dimensional image.

10. The information gathering device of claim 6, wherein the image is a higher- than-fourth-dimensional image.

11. The infonnation gathering device of claim 6, wherein the device is an ultrasound imaging device.

12. The information gathering device of claim 6, wherein the device is a magnetic resonance imaging device.

13. The information gathering device of claim 6, wherein the device is a computerized tomography imaging device.

14. The information gathering device of claim 6, wherein the device is a nuclear radioisotope imaging device.

15. The information gathering device of claim 6, wherein the device is a SQUID imaging device.

16. A parametric imaging device comprising: means for digitizing signals representing one or more selected parameters of an event; means for quantifying the signals representing one selected parameter of the event in an image, the quantifying means operatively connected to the digitizing means; and means for presenting a geometric image of the event, the presenting means operatively connected to the quantifying means and the digitizing means. wherein the digitizing means is configured and adapted to process the signals to RF signals.