Kazuhiro Iinuma

Ultrasonic diagnosing apparatus

An ultrasonic diagnostic apparatus comprising: a scanning device, the input device, the changing unit, a prediction unit, and second processors. The B-mode scanning means is provided for scanning and Doppler mode ultrasound scanning period is scanned by alternately. The input unit arranged to input instructions. During the first period of the second change unit is arranged to change according to an instruction B-mode scan and Doppler-mode scan; said prediction means to predict a first set period on a first Doppler signal. The processor is arranged to generate a first Doppler signal obtained by the Doppler-mode scan and a second Doppler signal Doppler mode image. The second processor is arranged to generate a B-mode image the B-mode signal obtained by B-mode scan.

Ultrasonic type blood flow amount measuring apparatus

A blood flow amount measuring apparatus includes an ultrasonic transducer for steering a region of interest of a subject to be measured with an ultrasonic beam and receiving echoes from that region. A Doppler calculation section detects a Doppler signal on a line orthogonal with the steering lines from the echo signal. The speed v of a blood flow on that line at the region of interest is calculated from the Doppler signal and thus and an amount of blood flowing through the region of interest can be evaluated from that speed and area area of the section of that blood flow.

A Barium-Titanate-Ceramics Capacitive-Type EEG Electrode

A capacitive-type electrode using barium titanate ceramics is described. This electrode is not affected by the polarization potential. Because its surface is chemically inactive and mechanically strong, its noise voltage is minimum from the beginning of its installation. This device is especially suitable for EEG recording.

Ultrasound transmitting or receiving apparatus

In an ultrasound transmitting or receiving apparatus, a plurality of ultrasound transducer elements comprising an ultrasound probe are arranged along a line to transmit and receive ultrasonic waves. For the purpose of sequentially transmitting and receiving an ultrasound beam through the transducer elements, variable-delay circuits are provided for applying delay times to the transmitting signals and/or the received signals. The variable-delay circuits include memory control devices, the addresses of which correspond to the respective azimuthal directions of transmitting and receiving the ultrasound beam. The outputs of the memory devices are connected to control terminals of transfer switches, which in turn are connected to tapped delay lines. The memory devices produce control codes such that the tapped delay lines produce predetermined delay times which control the azimuthal directions of transmitting or receiving the ultrasound beam.

Ultrasonic method and apparatus for tissue characterization and imaging nonlinear parameter

A method and apparatus for tissue characterization and imaging of nonlinear parameter data include an array of ultrasonic transducer elements to transmit ultrasonic pulses along a beam toward the tissue and to receive echoes of the ultrasonic pulses. The ultrasonic transducer elements are driven so that the ultrasonic pulses are transmitted at different power levels. The echoes of the ultrasonic pulses are analyzed at each of the different power levels to obtain the nonlinear parameter data along the beam. The beam is scanned in a two-dimensional plane of the tissue. The nonlinear parameter data is displayed according to the two-dimensional plane.

An evaluation of an in vivo local sound speed estimation technique by the crossed beam method

An in vivo local sound speed estimation technique, using the crossed beam method, has been proposed and its applicability was evaluated. At first, the potential of this technique was studied by a mapping simulation using the ray tracing technique followed by an experiment with a cylindrical agar phantom. The simulation result showed that an exact measurement of local sound speed values was difficult, but the sound speed information for the local region (its relative magnitude to the surrounding medium) was emphasized as a refraction mapping pattern. The experimental results agreed well with the calculation results. Furthermore, a clinical application was performed, using the clinical system (modified electronic linear scanner), on two liver tumor patients.

Ultrasonic Mass-Screening System for Breast Examination

A new ultrasonic mass-screening system for the early detection of breast cancer without palpation is described. This system has been developed in order to detect a tumor larger than 5 mm in size. The entire region where breast cancer may develop can be scanned at one time by rotating the 5 MHz waterproof array transducer in a water bath. The real-time B-mode image with a wide viewing width of 190 mm can be obtained by electronic linear scanning. The screening time is less than 5 minutes per examinee. This trial system is confirmed to be effective for clinical mass-screening.

High resolution electronic-linear-scanning ultrasonic diagnostic equipment.

Abstract Electronic linear-scanning ultrasonic diagnostic equipment so far has suffered from low resolution. In the study presented here, improvement in resolution was obtained by electronic focusing and improved image quality by small-angle deflection. Electronic focusing is a method obtaining a narrow ultrasonic beam by means of phase control. Small-angle deflection is a method to increase scanning line density by deflecting slightly the ultrasonic beam also by means of phase control and thus to obtain information existing between the successive scanning lines of a conventional linear scanning system. Both experimental investigation and clinical application have shown that these techniques are highly effective in increasing lateral resolution and image quality. It has been confirmed that the equipment is practical for routine use.

Measurement of Acoustic Impedance of Skin

It is important to know the characteristics of the acoustic impedance of a living tissue in order to diagnose with ultrasonic equipment or to design the equipment. Especially, in the immersion method of ultrasonic diagnosis, if strong reflections are produced from mis-matched interface between the skin and the water-bag and that between transducer and water, reverberations occur. The echo from the deep portion of body is disturbed by the reverberation and the strong echo from the mis-matched interface between the skin and the water-bag masks the weak echo from just under the skin. In these cases, it is difficult to make the diagnosis from the echo.

A Fundamental Evaluation of in Vivo Sound Speed Mapping Technique by Crossed Beam Method

Recently, several kinds of in vivo sound speed measurement techniques, using a pulse echo method, have been developed for the purpose of ultrasound tissue characterization.1,2,3The crossed beam method was proposed as a simple method by Haumschild and Greenleaf4 and Nishimura et al.5. This method uses two single probes. One probe is used for transmitting the ultrasound pulsed wave and the other for receiving the wave scattered from the region where the beams from the two probes cross. From the propagation time of the pulsed wave, the sound speed value is calculated. This method can also be realized using a linear array probe.6