Patent ID: 8353836
Filing Date: 2013-01-15
Classification: A61B

Abstract:
1. An ultrasonic diagnostic apparatus comprising: an ultrasonic probe; a transmitter having a transmission signal generating circuit for generating a ultrasonic wave made by continuous wave or pulse wave and selectively transmitting the ultrasonic wave to a subject via the ultrasonic probe; a receiver for phasing a reception signal received from the subject by the ultrasonic probe; a Doppler processing unit for calculating Doppler frequency shift in the reception signal output from the receiver and calculating blood flow velocity of the subject on the basis of the Doppler frequency shift; a display for displaying a time-varying waveform of the blood flow velocity; a controller for controlling the transmitter, the receiver, the Doppler processing unit, and the display; and a gray-level correcting unit for correcting gray level of an output result of the Doppler processing unit, wherein the gray-level correcting unit includes a filtering unit for separating a signal and a noise from each other, which are included in the time-varying waveform of the blood flow velocity of the subject obtained by the Doppler processing unit, with a correcting gray level of pixels of the time-varying waveform by using weighting values determined by a weighting function on the basis of differences between the gray level of each of the pixels and a gray level of each of the peripheral pixels thereof on a space defined by the blood flow velocity and time, and a gray-level corrector for performing a gray level correction using, as a parameter, a boundary value between signal intensity and noise intensity obtained by the filtering unit.