Surgery – Truss – Pad
Patent
1991-05-28
1992-12-08
Howell, Kyle L.
Surgery
Truss
Pad
12866108, A61B 812
Patent
active
051688778
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION
1. Technical Field
The present invention relates to an ultrasonic diagnostic apparatus having a blood flow imaging function of displaying, for example, the blood flow velocity in colors.
2. Background Art
One type of ultrasonic diagnostic apparatus having a so called color flow mapping (hereinafter referred to as "CFM") function, which enables the blood flow to be imaged using a different color for each particular blood flow velocity, is spreading rapidly because it permits the blood flow velocity to be determined easily. According to the CFM, scanning is effected with an ultrasonic beam while repeating the transmission and reception of an ultrasonic wave a minimal number of times for one direction, thereby displaying a two-dimensionally extending blood flow image.
Such an ultrasonic diagnostic apparatus includes a pulsed Doppler computing circuit that outputs a Doppler signal from a received signal obtained through a transmitting-receiving circuit, and a flow velocity computing section that determines a blood flow velocity, for example, on the basis of the Doppler signal. However, since the flow velocity computing section comprises a digital computing circuit that is for the exclusive use of it, the computing algorithm is fixedly determined by the circuit configuration and hence lacking in flexibility. Therefore, when the computing algorithm needs to be changed, the hardware configuration itself must be changed.
DISCLOSURE OF INVENTION
The present invention aims at solving the above-described problems, and it is an object of the present invention to obtain an ultrasonic diagnostic apparatus including a CFM system which is designed so that the computing algorithm can be changed easily in accordance with technical advance or a change in specifications.
The ultrasonic diagnostic apparatus according to the present invention comprises an A/D converter that converts a Doppler signal obtained by coherent detection of the echo reflected from an object of inspection into a digital signal, and a flow velocity computing section that determines a blood flow velocity and velocity dispersion on the basis of the Doppler signal from the A/D converter. The flow velocity computing section includes an MTI filter and a computing unit that determines a blood flow velocity and velocity dispersion by processing an output signal from the filter, both the MTI filter and the computing unit comprising respective digital signal processors (DSPs).
BRIEF DESCRIPTION OF THE DRAWINGS
The figure is a block diagram showing the arrangement of an ultrasonic diagnostic apparatus according to one embodiment of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a block diagram showing the arrangement of an essential part of an ultrasonic diagnostic apparatus according to one embodiment of the present invention. In the figure, reference numeral 1 denotes a probe that sends out an ultrasonic signal into an object 2 of inspection and receives an echo signal reflected from the object 2, and 3 a transmitting-receiving circuit that drives the probe 1 and also receives the echo signal. A logarithmic amplifier circuit 4 logarithmically amplifies the echo signal received by the transmitting receiving circuit 3, and an analog-to-digital converter (hereinafter referred to as "A/D converter") 5 converts the echo signal (analog signal) amplified in the logarithmic amplifier circuit 4 into a digital signal. The logarithmic amplifier 4 and the A/D converter 5 constitute a B-mode signal processing system.
A Doppler demodulator circuit 6 divides the received signal into two-channel signals, which are multiplied by respective reference waves which are 90.degree. out of phase with each other to detect a Doppler signal. Reference numerals 7a and 7b denote low-pass filters, and 8a and 8b A/D converters.
A flow velocity computing section 9 includes buffer memories 10a and 10b that alternately store signals from the A/D converters 8a and 8b for each sound ray. Reference numerals 11a and 11b denote digital signal processor
REFERENCES:
patent: 4911171 (1990-03-01), Uchibori
patent: 4955386 (1990-09-01), Nishiyama et al.
patent: 4993417 (1991-02-01), Seo
Hirota Yuichi
Jibiki Takao
Yamaguchi Keiki
Howell Kyle L.
Kojima Moonray
Manuel George
Yokogawa Medical Systems Limited
LandOfFree
Ultrasonic diagnostic apparatus 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 apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ultrasonic diagnostic apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-955089