Abstract: An improved method and apparatus for evaluating the performance of an individual. In one aspect, the invention includes a method of encoding questions used in an examination in order to accurately identify and evaluate deficiencies in an individual's knowledge. In another aspect, an improved method of evaluating responses to the encoded questions is disclosed. Adaptive structuring of subsequent exam questions and/or topics is also provided. A computer program and associated apparatus for administering and evaluating performance is also described.

Abstract: An improved method and apparatus for evaluating the performance of an individual. In one aspect, the invention includes a method of encoding questions used in an examination in order to accurately identify and evaluate deficiencies in an individual's knowledge. In another aspect, an improved method of evaluating responses to the encoded questions is disclosed. Adaptive structuring of subsequent exam questions and/or topics is also provided. A computer program and associated apparatus for administering and evaluating performance is also described.

Abstract: An improved method and apparatus for non-invasively assessing one or more hemodynamic parameters associated with the circulatory system of a living organism. In one aspect, the invention comprises a method of measuring a hemodynamic parameter by measuring a non-calibrated value of the parameter non-invasively, and inducing a stress of the circulatory system while measuring a second parameter. The response of the circulatory system to the stress is determined directly from the subject, and a calibration function is derived from the response and applied to the non-calibrated measured value to produce a calibrated measure of the actual value of the hemodynamic parameter. Methods of using backscattered acoustic energy for determination of hemodynamic markers are also disclosed.

Abstract: A method and apparatus for determining the mean arterial blood pressure (MAP) of a subject during tonometric conditions. In one embodiment, the apparatus comprises one or more pressure and ultrasound transducers placed over the radial artery of a human subject's wrist, the latter transmitting and receiving acoustic energy so as to permit the measurement of blood velocity during periods of variable compression of the artery. In another aspect of the invention, a wrist brace useful for measuring blood pressure using the aforementioned apparatus is disclosed. In yet another aspect of the invention, backscattered acoustic energy is used to identify the location of the blood vessel of interest, and optionally control the position of measurement or treatment equipment with respect thereto.

Abstract: An improved method and apparatus for evaluating the performance of an individual. In one aspect, the invention includes a method of encoding questions used in an examination in order to accurately identify and evaluate deficiencies in an individual's knowledge. In another aspect, an improved method of evaluating responses to the encoded questions is disclosed. Adaptive structuring of subsequent exam questions and/or topics is also provided. A computer program and associated apparatus for administering and evaluating performance is also described.

Abstract: An improved method and apparatus for non-invasively assessing one or more hemodynamic parameters associated with the circulatory system of a living organism. In one aspect, the invention comprises a method of measuring a hemodynamic parameter by measuring a non-calibrated value of the parameter non-invasively, and inducing a stress of the circulatory system while measuring a second parameter. The response of the circulatory system to the stress is determined directly from the subject, and a calibration function is derived from the response and applied to the non-calibrated measured value to produce a calibrated measure of the actual value of the hemodynamic parameter. Methods of using backscattered acoustic energy for determination of hemodynamic markers are also disclosed.

Abstract: An improved method and apparatus for non-invasively assessing one or more hemodynamic parameters associated with the circulatory system of a living organism. In one aspect, the invention comprises a method of measuring a hemodynamic parameter by measuring a non-calibrated value of the parameter non-invasively, and inducing a stress of the circulatory system while measuring a second parameter. The response of the circulatory system to the stress is determined directly from the subject, and a calibration function is derived from the response and applied to the non-calibrated measured value to produce a calibrated measure of the actual value of the hemodynamic parameter. Methods of generating a tissue transfer function from measurements of the subject, correcting for periodic or aperiodic error components, and providing treatment to the subject based on the measured hemodynamic parameters, are also disclosed.

Abstract: The invention implements a method for adaptively using raw image data (before compression) to produce pixel display values in an ultrasound system in accord with variations in signal-to-noise ratio. Initially, for each subject pixel of an image, a first regional value is derived by taking into account values of a neighborhood of pixels that includes the subject pixel. The first regional value is then compared to a threshold value related to noise and each subject pixel is assigned a classification as a tentative signal pixel if the regional value equals or exceeds the threshold value. Any pixel value not so classified is considered a tentative noise pixel. A second regional value is then derived for each subject pixel by taking into account first regional classifications of a second neighborhood of pixels that includes the subject pixel. If the number of signals classified as signal in the second neighborhood is less than a second threshold, the subject pixel is classified as noise.

Abstract: An improved method and apparatus for non-invasively assessing one or more hemodynamic parameters associated with the circulatory system of a living organism. In one aspect, the invention comprises a method of measuring a hemodynamic parameter by measuring a non-calibrated value of the parameter non-invasively, and inducing a stress of the circulatory system while measuring a second parameter. The response of the circulatory system to the stress is determined directly from the subject, and a calibration function is derived from the response and applied to the non-calibrated measured value to produce a calibrated measure of the actual value of the hemodynamic parameter. Methods of using backscattered acoustic energy for determination of hemodynamic markers are also disclosed.

Abstract: A method and apparatus for determining the mean arterial blood pressure (MAP) of a subject during tonometric conditions. In one embodiment, the apparatus comprises one or more pressure and ultrasound transducers placed over the radial artery of a human subject's wrist, the latter transmitting and receiving acoustic energy so as to permit the measurement of blood velocity during periods of variable compression of the artery. In another aspect of the invention, a wrist brace useful for measuring blood pressure using the aforementioned apparatus is disclosed. In yet another aspect of the invention, backscattered acoustic energy is used to identify the location of the blood vessel of interest, and optionally control the position of measurement or treatment equipment with respect thereto.

Abstract: The present invention provides a method and apparatus for processing acoustic information obtained with an ultrasound device to generate cardiac information, such as, for example, a patient's heart rate. In accordance with the present invention, an ultrasound system is utilized to image a patient's heart to obtain acoustic information relating to the patient's heart. The acoustic information is converted into electrical information, which is then processed to extract a particular feature of interest therefrom, such as, for example, the patient's heart rate. In accordance with the preferred embodiment of the present invention, processing of the electrical signals comprises the steps of generating a time-series from a series of image frames and then performing a spectral analysis on the time-series. The features of interest are then easily extracted from the results of the spectral analysis.

Abstract: In the present invention, a control system uses acoustic data produced by an ultrasound system to assess whether the acoustic environment presented to the ultrasound system's transducer is an imaging environment, such as patient's body, or a nonimaging environment, such as air. Various operating parameters of the ultrasound system may be controlled based on the assessment. In the nonimaging environment, the control system reduces the amplitude of a drive signal applied to the transducer, substantially reducing power dissipation in the transducer. The control system detects a transition to the imaging environment and returns the drive signal to the amplitude used in the previous imaging environment. If the nonimaging environment persists for greater than a predetermined time period, the control system initiates a standby mode which substantially reduces power consumption by the ultrasound system. The control system is readily integrated into the imaging stream of an ultrasound system.