Abstract: A system is disclosed for synchronizing the activation of an imaging device, such as an X-ray machine, with patient respiration. The imaging device includes a conventional trigger signal input for activating the imaging device in response to a preset signal. The system includes a respirator device, such as a ventilator or respiration band, which provides an output signal indicative of the degree of patient inspiration. A processing circuit is responsive to the output signal from the respiration device and generates the preset signal at a preselected degree of patient inspiration. The output signal from the processing circuit is coupled to the imaging device signal input to activate the imaging means at the preselected degree of patient inspiration.

Abstract: An image generation unit 102 generates image data of a tomographic image based on an electric signal received from a send/receive unit 12 through a control unit 101. An ROI setting unit 103 sets an ROI to the generated tomographic image. A characteristic value extraction unit 104 extracts a characteristic value (such as volume of left ventricular of a heart) to the set ROI. A synchronization generation unit 105 generates a synchronization signal based on the extracted characteristic value. A synchronization information addition unit 106 adds information that represents the generated synchronization signal to image data and stores the image data in an image data storage unit 107. A data reading unit 109 reads out the image data to which the information that represents the synchronization signal is added from the image data storage unit 107. An image display unit 111 displays a tomographic image of the read-out image data.

Abstract: A database is created that contains a plurality of data items gathered from many human beings wherein the data items affect the heart rate of a patient during a CT imaging procedure. Regression analysis is performed on the data in the database to derive an algorithm which defines an predicted heart rate value as a function of the plurality of data items. Specifically, values for the plurality of data items are obtained for the particular patient to be imaged and the algorithm is applied to those data items to predict the patient's heart rate which will occur during the CT imaging procedure. The predicted heart rate is employed to defined operating parameters of the CT procedure, such as the rate at which the x-ray source and detector rotate around a patient and the speed at which the patient moves through the imaging plane.

Abstract: A method of synchronizing initiation of a magnetic resonance image (MRI) acquisition to the arrival of a contrast agent in a structure of interest, such as an artery, includes repeatedly performing a first MRI scan until the first MRI scan indicates that the contrast agent has arrived. The first MRI scan acquires a three-dimensional MRI data set from the structure of interest. Preferably, the first MRI scan is a partial MRI scan that produces a low resolution image. Once the first MRI scan indicates that the contrast agent has arrived in the structure of interest, a second MRI scan is performed that acquires a second three-dimensional MRI data set from the structure of interest. The second MRI scan is preferably a full MRI scan that produces a full fidelity image. The manner of data acquisition is advantageously the same for both the first MRI scan and the second MRI scan.

Abstract: The subject invention pertains to a novel method and apparatus for improving the efficacy of a medical treatment or diagnostic procedure by coordinating such treatment or procedure with at least one physiological cycle of a patient. In a specific embodiment, the subject invention pertains to a novel method of coordinating a chest x-ray with a patient's ventilatory cycle. In a specific example, this invention concerns a novel device for interfacing a ventilator and an x-ray machine to ensure that an x-ray chest image can be taken at peak insufflation of the patient. The subject invention also relates to other medical procedures including, but not limited to, cardiac output measurement, chest imaging, inhalation therapy, oxygen delivery, blood pressure measurement, extracorporel shock wave lithotripsy, and pulse oximeter optoplethysmograms.

Abstract: An MR imaging method wherein motion of an object to be imaged is examined during a preparation phase preceding the actual MR examination. The necessary sequences for the subsequent MR examination are modified during the examination to compensate for the motion based on motion parameters calculated during the preparation phase or motion parameters derived from the motion parameters calculated during the preparation phase based on a correlation between the motion parameters.

Abstract: A database is created that contains a plurality of data items gathered from many human beings wherein the data items affect the heart rate of a patient during a CT imaging procedure. Regression analysis is performed on the data in the database to derive an algorithm which defines an predicted heart rate value as a function of the plurality of data items. Specifically, values for the plurality of data items are obtained for the particular patient to be imaged and the algorithm is applied to those data items to predict the patient's heart rate which will occur during the CT imaging procedure. The predicted heart rate is employed to defined operating parameters of the CT procedure, such as the rate at which the x-ray source and detector rotate around a patient and the speed at which the patient moves through the imaging plane.

Abstract: A trackable medical instrument includes a guide member and an emitter array coupled to the guide member. A drive shaft is rotatably coupled to the guide member, and a locking mechanism is provided along the drive shaft. The emitter array emits a signal that is used to track the position of the guide member. The locking mechanism has an unlocked position in which the drive shaft rotates relative to the guide member. The locking mechanism also has a locked position in which the drive shaft is rotationally stationary relative to the guide member. A processor tracks medical instruments using a sensor array and a reference array. A display that is operatively coupled to the processor displays the position of the instrument in relation to a patient.

Abstract: A homodyne interference system splits first and second light beams from a common light source and causes the first and second light beams to impinge upon an irradiating point of an organism at different directions. An optical heterodyne system splits a third beam from the common light source and imparts a frequency shift to the third beam. The outputs of the homodyne and heterodyne systems combine to permit extraction of a beat component of the homodyne system at a high SNR level. The output of the homodyne and heterodyne system are output as an image, which may be timed to a phase timing mechanism to provide an improved output.

Abstract: The present invention provides a new imaging method/system for skeletal muscle function assessment. A gating system triggers imaging device such as magnetic resonance scanner to provide reproducible image data at specific force levels and/or joint angular positions. The present invention further provides applications of such method/system in muscle studies and diagnostics.

Abstract: A computer controlled system for guiding the needle device, such as a biopsy needle, by reference to a single mode medical imaging system employing any one of computed tomography imaging (CTI) equipment, magnetic resonance imaging equipment (MRI), fluoroscopic imaging equipment, or 3D ultrasound system, or alternatively, by reference to a multi-modal imaging system, which includes any combination of the aforementioned systems. The 3D ultrasound system includes a combination of an ultrasound probe and both passive and active infrared tracking systems so that the combined system enables a real time image display of the entire region of interest without probe movement.

Abstract: A nuclear magnetic resonance imaging apparatus in which a synchronizing signal is generated from a periodic physiological signal generated by a subject to be inspected, and a radiofrequency burst pulse is applied to the subject to be inspected in synchronism with the synchronizing signal while a gradient magnetic field in one direction is being applied to the subject to be inspected to modulate nuclear magnetizations of the subject to be inspected in the one direction. The radiofrequency burst pulse includes plural sub-pulses which are formed at equidistant intervals on a time axis and which have amplitudes modulated by a sinc function.

Abstract: Enhanced information on the electrical properties of the subregions of a sample is generated by an enhanced tomography (EPET) apparatus connected to a tomographic device, wherein the EPET apparatus holds a voltage constant and measures the electrical current of the sample inserted within the EPET apparatus. A matching medium is applied to the sample such that when the sample is placed within an electromagnetic field generated by the EPET apparatus, the matching medium contacts the segmented sensor plates of the EPET apparatus and allows the detection of the net total charges Q on the surface of the sample. The EPET apparatus uses these net total charges Q in the calculation of the additional information on the electrical properties of the sample by using the scale factor method or the iterative correction method.

Abstract: A method of imaging a patient with an MRI scanner (10) includes imaging a region of interest of the patient with the MRI scanner (10) and acquiring image data resulting from the imaging. An image of the region of interest is reconstructed from the image data. The method also includes generating navigator echos during the imaging, collecting the navigator echos and deriving, from each navigator echo, a measurement of patient motion experience during the imaging. A historical record of the measurements is maintained. Parameters for the acquisition of image data are selected to compensate for motion, or specific image data is selected for reconstruction, based on the historical record.

Abstract: A method of cardiac gating for use in an imaging apparatus includes monitoring a patient's cardiac cycle, and determining a cardiac cycle time for the patient. A desired cardiac phase of interest is selected, and a delay from a reference point in the cardiac cycle is determined. The delay is a function of the selected cardiac phase and the cardiac cycle time. Finally, the selected cardiac phase is located in the cardiac cycle using the delay. This cardiac gating method compensates for non-uniform changes in the patient's cardiac cycle corresponding to a non-uniform distribution of cardiac phases in the patient's cardiac cycle.

Abstract: From ECG-gated SPECT or PET images of radioactive myocardial perfusion imaging agents, contraction of the myocardium along the tangential direction, i.e., in the direction parallel to the myocardium, can be evaluated. The amount of the agents which accumulate in the heart muscle is calculated from reconstructed short-axis ECG-gated images and is projected on a virtual cylindrical screen whose axis is the same as the long axis of the heart. Spatial and temporal changes in time and space in the projected count distribution on the screen are described by a two-dimensional second order differential equation, which is called an equation of continuity for the fluid. This equation can be solved numerically with a computer. The displacements of points on the myocardium in the tangential direction are calculated by projecting the displacement of each point back onto the cardiac wall. From these displacements, contraction and expansion of the heart muscle can be quantified.

Abstract: In a method for operating a magnetic resonance tomography apparatus, a basic magnetic field is produced and at least one magnetic gradient field is switched that comprises a main field component that is co-linear to the basic magnetic field, having a predetermined main gradient, this gradient field also having at least one accompanying field component that is perpendicular to the main field component, and also having a linearity volume. An additional magnetic field that is as homogenous is possible is thereby switched (activated) that extends beyond the linearity volume, and this additional magnetic field is switched at least for a duration of time in which the gradient field is also switched. This additional magnetic field is oriented such that it reduces at least one of the field components in at least one region of anticipated stimulation of the examination subject.

Abstract: This invention relates to methods and apparatus for medical imaging of parts of a patient in which imaging data acquisition is gated by a combination of electrocardiogram (ECG) and peripheral pulse (PPU) signals from the patient. The methods of the invention include obtaining ECG signals from a patient in a medical imaging apparatus, obtaining PPU signals from the patient, providing one or more synchronization signals in dependence on both the ECG signals and the PPU signals, wherein the synchronization signals indicate occurrences of pre-determined phases of the cyclic movements of the heart only if the PPU signals also indicate that the determined heart phase is physiologically possible, and controlling the medical imaging apparatus in dependence on the synchronization signals to collect imaging data synchronized with cyclic movements of the heart from the patient in the examination zone and to reconstruct a medical image of a part of the patient from the collected imaging data.

Abstract: A method for stabilizing and optimizing angiogram cine runs. The method for stabilizing involves reducing abrupt motion from the last frame to the first frame by refining the choice of the estimates of first and last frame indices provided by the user and by performing image registration so that a feature of interest is nearly in the same position between the last and first frame. According to another aspect, a network accessible system for storing and playing back angiographic images and presenting patient information is provided. The most diagnostically relevant subset of frames are extracted from selected cine runs and made available over a wide area network (WAN) such as the Internet.

Abstract: The invention relates to a method of and a device for determining the position of a medical instrument (4), introduced into the body of a patient (2), relative to a periodically moving organ (3) of the body, which method includes the steps of: a) determining the spatial position (c, r) of the medical instrument (4) and of a reference probe (6) while acquiring at the same time a periodic motion signal (E2) which relates to the periodic motion of the body organ (3), b) selecting a 3D image data set (p) from an image data base which contains 3D image data sets (p) of the body organ (3) which have been acquired pre-operatively and simultaneously with the same motion signal (E1) and are associated with individual motion phases (e1, e2, . . . ), in such a manner that that 3D image data set (p) is selected which is associated with the motion phase (e1, e2, . . .

Abstract: Noninvasive, MR-compatible methods and systems optically detect mechanical cardiac activity by anatomic (e.g., esophageal) movements. Most preferably, esophageal motion is detected optically and is indicative rhythmic cardiac activities. This esophageal motion may then be detected and used to provide a signal indicative of periods of cardiac activity and inactivity. The signal may be further processed so as to generate a trigger signal that may be input to a MR scanner. In such a manner, MR microscopy may be accomplished to acquire information at a specific phase of the cardiac cycle, for example, in synchrony with periods of cardiac inactivity. Moreover, since mechanical cardiac activity is detected and employed, instead of electrical activity as is employed in conventional techniques, the present invention is immune to electromagnetic interference during MR microscopy. As a result, robust cardiac signals may be monitored and gated during 2-dimensional and 3-dimensional in vivo microscopy.

Abstract: A method is described for controlling x-ray exposure during gated cardiac scanning, including the steps of detecting a first cardiac signal; starting scanning after a pre-selected wait time after detecting the first cardiac signal; and stopping the scanning after a first to occur of passage of a pre-selected data collection time and detection of a second cardiac signal.

Abstract: A method for estimating motion of a part of an object, using a CT imaging system, is therefore provided in one embodiment of the present invention. This method includes steps of: scanning the object with the CT imaging system so as to acquire conjugate data samples; analyzing the conjugate data samples to remove data representative of overlapping, non-moving portions of the object; and estimating a cardiac motion from the analyzed conjugate data samples. Advantageously, no EKG device is required estimating cardiac motion when this method for estimating motion is employed.

Abstract: The subject invention pertains to a novel method and apparatus for improving the efficacy of a medical treatment or diagnostic procedure by coordinating such treatment or procedure with a patient's breathing cycle. In a specific embodiment, the subject invention pertains to a novel method of coordinating a chest x-ray with a patient's ventilatory cycle. In a specific example, this invention concerns a novel device for interfacing a ventilator and an x-ray machine to ensure that an x-ray chest image can be taken at peak insufflation of the patient. The subject invention also relates to other medical procedures including, but not limited to, cardiac output measurement, chest imaging, inhalation therapy, oxygen delivery, blood pressure measurement, and pulse oximeter optoplethysmograms. By coordinating certain medical treatments and diagnostic procedures with a patient's breathing cycle, the subject invention improves the quality of medical care received by the patient.

Abstract: A method and system for gating therapeutic or diagnostic energy to a tissue volume of a medical patient during a selected portion of the patient's respiratory cycle, to thereby diminish inaccuracies in the assumed spatial position of the tissue volume arising from displacements induced by the patient's respiration. The gases flowing to and from the patient's lungs are monitored to provide quasi-continuous measurements as a function of time, for any selected subset of (a) flow rate, (b) pressure, (c) patient lung volume and (d) carbon dioxide concentration. The measurements are utilized to trigger the time period during which the energy is gated on, at the beginning of the selected portion of the respiration cycle; and the time period during which the energy is gated on, is terminated at the end of the selected portion of the respiration cycle.

Abstract: The subject invention pertains to a novel method and apparatus for improving the efficacy of a medical treatment or diagnostic procedure by coordinating such treatment or procedure with a patient's breathing cycle. In a specific embodiment, the subject invention pertains to a novel method of coordinating a chest x-ray with a patient's ventilatory cycle. In a specific example, this invention concerns a novel device for interfacing a ventilator and an x-ray machine to ensure that an x-ray chest image can be taken at peak insufflation of the patient. The subject invention also relates to other medical procedures including, but not limited to, cardiac output measurement, chest imaging, inhalation therapy, oxygen delivery, blood pressure measurement, and pulse oximeter optoplethysmograms. By coordinating certain medical treatments and diagnostic procedures with a patient's breathing cycle, the subject invention improves the quality of medical care received by the patient.

Abstract: In a computed tomography apparatus, and a method for operating same, for obtaining cardiac images, a spiral scan of a measurement volume containing a patient's heart is conducted, the production of the scanning data during the spiral scanning being synchronized with an ECG signal from the patient, in order to produce a graphic representation of the examination volume, and thus an image of the patient's heart. The ECG signal is employed to control the generation of the data during the spiral scanning at phase of the cardiac cycle wherein minimum movement of the heart takes place. The chronological correlation between the recording of the scanning data and the ECG signal is fixed, so that within each number of successive time intervals, a dataset is obtained completely within that time interval. The datasets from the successive time intervals are then combined to produce an image of the heart.

Abstract: Apparatus and method are provided for constructing image slices through a selected object undergoing a cyclic motion wherein a scanner is used for collecting image data associated with the selected object. A probe is provided for detecting a signal from the selected object, the signal being indicative of the cyclic motion of the object. The scanner and the probe are operatively connected with a controller. The controller receives the signal from the probe and generates therefrom a command for enabling the scanner to collect image data for producing one or more image slices through the selected object with minimized radiation exposure and data acquisition time.

Abstract: The radiology instrument contains a source emitting X-radiation, a radiological image receiver, a chassis arranged between the X-ray source and the image receiver in order to accommodate an object to be radiographed, and a positioning and guiding device which can be connected to the chassis and can intercept the X-radiation so as to position and guide probes intended to interact with the object. The positioning and guiding device has first means forming a retractable guide grid having holes whose respective axes converge towards the focal point of the source when the first means intercept the conical radiation, and a retractable positioning grid with holes.

Abstract: A method and system for gating therapeutic or diagnostic energy to a tissue volume of a medical patient during a selected portion of the patient's respiratory cycle, to thereby diminish inaccuracies in the assumed spatial position of the tissue volume arising from displacements induced by the patient's respiration. The gases flowing to and from the patient's lungs are monitored to provide quasi-continuous measurements as a function of time, of (a) flow rate, (b) pressure, (c) patient lung volume and (d) carbon dioxide concentration. The measurements are utilized to trigger the time period during which the energy is gated on, at the beginning of the selected portion of the respiration cycle; and the time period during which the energy is gated on, is terminated at the end of the selected portion of the respiration cycle.

Abstract: By employing controlled setting of a phase-encoding direction in MRI, for imaging a tissue or blood flow composed of spins whose time T.sub.2 is rather short or ranges from 100 to 200 milliseconds, signal levels induced by the blood flow or the like are raised in order to maintain a good signal-to-noise ratio. An image enjoying an excellent depiction ability can be produced without the loss of information of directivities of blood flows or tissues running in diverse directions. An MRI system utilizing the Fourier transform comprises an element for scanning the same region to be imaged of a subject a plurality of times while changing phase-encoding directions, and an element for producing image data of one frame on the basis of MR rawdata of a plurality of frames.

Abstract: Delays in event detection in time-varying data can be reduced by predicting the time-varying data and then detecting the event in the predicted data. This finds application in the triggering of medical imaging devices, where physiological events can be detected in the time-varying data. An artificial neural network can be trained to predict data such as ECG signals from which a detection algorithm can accurately predict the occurrence of an event that will serve as a reference point for triggering.