Surgery – Diagnostic testing – Detecting nuclear – electromagnetic – or ultrasonic radiation
Reexamination Certificate
2002-03-05
2004-05-04
Jaworski, Francis J. (Department: 3737)
Surgery
Diagnostic testing
Detecting nuclear, electromagnetic, or ultrasonic radiation
C128S916000
Reexamination Certificate
active
06730032
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an ultrasonic diagnostic device and an image processing device, and particularly to a technique for improving a time resolution of a sequence of ultrasound images obtained at a predetermined frame rate.
2. Description of Background Art
An ultrasonic diagnostic device receives an echo obtained when ultrasound emitted from an ultrasonic probe is partially reflected on reflection points and surfaces of tissue of an object of a living body to be examined. The ultrasonic diagnostic device then performs signal processing for the received echo, and generates an ultrasound image (an echo image) for the examined object. Since the ultrasonic diagnostic device generates a two-dimensional (2D) ultrasound image of an examined object of a soft part and the like without invasion, it is widely used as a device which performs examination with high level of safety, and therefore is essential in fields such as clinical medicine.
As digital ultrasonic diagnostic devices are in increasingly widespread use, a variety of ultrasonic examinations are conducted with them.
For instance, an ultrasonic diagnostic device continuously samples ultrasound images of an examined object over a predetermined time and accumulates them to allow the operator to later closely examine a sequence of these ultrasound images and their physical quantity, such as movement of the object, and use obtained information for diagnosis.
For closely examining constantly changing movement of the object such as a heart and a circulatory organ, however, the present frame rate (e.g., 10 frames/second (fps)) used by an ultrasonic diagnostic device is not sufficient.
Methods considered to solve this problem include a method for raising a frame rate of sampling by reducing a total number of pixels constituting each ultrasound image, and density resolution of each pixel, and a method for omitting real-time processing from signal and image processing. These methods, however, reduce information amount of each ultrasound image, and so cannot improve accuracy of examination as a whole.
There is also a new technique of accurate examination by the use of an ultrasonic diagnostic device, which uses ultrasound images corresponding to different cross sections (such as a two-chamber view and a four-chamber view) of the same object (such as a heart). These ultrasound images have been generated in the same phase in a pulsation (i.e., relatively the same time in a pulsation cycle), so that examination with increased accuracy can be performed (see Japanese Patent Application No. 2001-23819).
With this technique, ultrasound images in the same phase are extracted from different sequences of ultrasound images. However, there are not always ultrasound images in the same phase within these sequences because timing with which these ultrasound images have been sampled and generated may differ from one another.
Consequently, ultrasound images generated in different phases are used as ultrasound images in the same phase, but such difference in phase results in decreasing accuracy of examination.
SUMMARY OF THE INVENTION
The present invention is made in view of the above problems, and aims to achieve the following three objects.
As the first object, the present invention aims to provide an ultrasonic diagnostic device and an image processing device capable of examination with increased accuracy by increasing an apparent sampling rate applied to an ultrasound image they generates without sacrificing a resolution of the ultrasound image and real-time performance.
As the second object, the present invention aims to provide an ultrasonic diagnostic device and an image processing device capable of examination with increased accuracy even when the devices use two or more ultrasound image sequences that have been generated in different phases as a result of difference in their sampled times.
As the third object, the present invention aims to provide an ultrasonic diagnostic device and an image processing device capable of accurately examining an object (such as a left ventricle (LV) of a heart) whose information (such as that showing a left ventricular volume (LVV)) used for diagnosis changes over time. To achieve this, the ultrasonic diagnostic device and the image processing device generate an ultrasound image corresponding to an predicted time at which the diagnostic information takes a characteristic value.
For achieving the first object, the ultrasonic diagnostic device and the image processing device generate ultrasound images through sampling, associates each of the generated ultrasound image with a time stamp, and interpolates between data of the ultrasound image to generate image data corresponding to a time at which the sampling was not performed.
The second object can be achieved by normalizing a cycle for ultrasound image data in accordance with time stamps associated with the ultrasound image data, and then performs the above interpolation between the ultrasound image data corresponding to the normalized cycle.
The third object can be achieved by predicting a time at which a left ventricular volume (LVV) becomes a minimum or a maximum, and generates an ultrasound image at the predicted time.
In more detail, the above objects can be achieved by an ultrasonic diagnostic device that generates and displays an ultrasound image containing an image of an object which is subject to examination in accordance with reflection of ultrasound. This ultrasonic diagnostic device includes: an image generating unit for successively generating an ultrasound image; a quantity extracting unit for extracting a characteristic quantity related to the object within the generated ultrasound image; a time stamp generating unit for generating a time stamp indicating a time at which the ultrasound image has been generated, and associating the time stamp with the extracted characteristic quantity to make a pair; an interpolating unit for performing interpolation using a plurality of pairs made by the time stamp generating unit so as to generate new characteristic quantities corresponding to times other than times indicated by time stamps contained in the plurality of pairs; an information generating unit for generating diagnostic information on the object in accordance with the new characteristic quantities; and a display unit for displaying the generated diagnostic information.
The above interpolation on characteristic quantities generates new characteristic quantities that each correspond to a time at which sampling was not performed, and diagnostic information based on such characteristic quantities can be generated. Consequently, the above ultrasonic diagnostic device can achieve examination with higher accuracy than conventional examination using the same frame rate as the present examination. In addition, since such highly accurate examination can be achieved by data processing such as interpolation of characteristic quantity, it costs lower than other method which increases a maximum frame rate.
Here, the above ultrasonic diagnostic device may further include: a pulsation detecting unit for detecting every pulsation related to the object; and a clock unit for measuring an elapsed time from the detection of each pulsation. Here, a time indicated by each time stamp may be an elapsed time measured by the clock unit.
For this construction, a value of the time stamp is incremented in synchronization with a pulsation of the object. This allows different sets of data that have been generated in the same phase in a pulsation cycle to be specified out of sets of data obtained at different times. Consequently, with the present diagnostic device, movements of the living body can be examined from a variety of viewpoints in synchronization with pulsations.
Here, for the above ultrasonic diagnostic device, the interpolating unit may (a) superimpose a plurality of characteristic quantities over one another within a single pulsation cycle, the plurality of characteristic quantities having been extracted over
Matsushita Electric Industrial Co.
Wenderoth , Lind & Ponack, L.L.P.
LandOfFree
Ultrasonic diagnostic device and image processing device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ultrasonic diagnostic device and image processing device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ultrasonic diagnostic device and image processing device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3218549