Imaging apparatus, method of controlling imaging apparatus, computer program, and computer readable storage medium

Patent metadata

Field	Value
Publication number	US-11701003-B2
Application number	US-201816140774-A
Country	US
Kind code	B2
Filing date	Sep 25, 2018
Priority date	Mar 25, 2016
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

A pulse signal corresponding to rotation of an imaging core is input, and a repetition frequency of the input pulse signal is converted in accordance with the number of radially-aligned lines of an ultrasound tomographic image. Based on the pulse signal of which the repetition frequency has been converted, a drive signal for an ultrasound transceiver is generated to obtain an ultrasound tomographic image with the number of lines. A valid pulse is determined in accordance with the number of lines from the pulse signal of which the repetition frequency has been converted. A signal having a pulse train selected, based on the valid pulse from a pulse signal representing a cycle of a light source of light for interfering with the light from an optical transceiver is generated as a pulse signal representing a timing of sampling of an optical coherence signal for generating an optical tomographic image.

First claim

What is claimed is:

1. An imaging apparatus configured to generate an ultrasound tomographic image and an optical tomographic image of a target site of a subject using a catheter which rotatably accommodates an imaging core provided with an ultrasound transceiver configured to transmit and receive an ultrasound wave and an optical transceiver configured to transmit and receive light, the imaging apparatus comprising:
a motor drive unit configured to be connected to the catheter and to rotate the imaging core;
a converter configured to receive a pulse signal corresponding to rotation of the imaging core and to convert a repetition frequency of the pulse signal into a converted pulse signal in accordance with a set number of radially-aligned lines configuring one frame of the ultrasound tomographic image;
a transmitting and receiving board configured to generate a drive signal for the ultrasound transceiver and to obtain the ultrasound tomographic image with the set number of radially-aligned lines based on the converted pulse signal to transmit the generated drive signal to the ultrasound transceiver via the motor drive unit; and
a logic device configured to determine a valid pulse in accordance with the set number of radially-aligned lines from the converted pulse signal and to generate a pulse signal representing a timing of sampling of an optical coherence signal for generating the optical tomographic image having a pulse train selected, based on the valid pulse from a pulse signal representing a cycle of a light source generating light for interfering with light from the optical transceiver by setting from pulses in the converted pulse signal, as the valid pulse, a pulse according to a ratio between a number of set lines of the ultrasound image of one frame and a number of set lines of one frame of the optical tomographic image of one frame, selecting the pulse immediately after the valid pulse from the pulse signal representing the cycle of the light source, and generating a signal having the selected pulse train as the pulse signal representing the timing of the optical coherence signal.

2. The imaging apparatus according to claim 1 , further comprising:
a first A/D (analog to digital) converter and a second A/D (analog to digital) converter, and wherein the transmitting and receiving board is configured to transmit to the first A/D converter a signal of a reflected wave of the ultrasound wave received from the ultrasound receiver via the motor drive unit.

3. The imaging apparatus according to claim 2 , further comprising:
an optical unit configured to output to the logic device, a pulse signal having a frequency equal to that of the light source of wavelength sweeping light that is supplied to the imaging core.

4. The imaging apparatus according to claim 3 , wherein the logic device is configured to output the pulse signal from the converter to the first A/D converter.

5. The imaging apparatus according to claim 4 , wherein the logic device is configured to detect when the valid pulse from pulses from the converter, a pulse input from the optical unit immediately after the detection is output to the second A/D converter.

6. The imaging apparatus according to claim 5 , wherein the first A/D converter is configured to perform an A/D conversion on the signal of the reflected wave of the ultrasound wave corresponding to the pulse received from the logic device, which the transmitting and receiving board has received from the ultrasound transceiver via the motor drive unit and transmits the A/D converted signal to a signal processing unit of a control unit.

7. The imaging apparatus according to claim 6 , wherein the second A/D converter is configured to perform an A/D conversion on the pulse signal of the interference light corresponding to the pulse received from the logic device from the optical unit and to transmit the A/D converted signal to the signal processing unit of the control unit.

8. The imaging apparatus according to claim 7 , wherein the signal processing unit is configured to generate line data of each line of the ultrasound tomographic image based on the signal from the first A/D converter and to generate line data of each line of the optical tomographic image based on the signal from the second A/D converter; and
wherein the signal processing unit of the control unit is configured to store the generated line data of each line of both of the ultrasound tomographic image and the optical tomographic image in a memory.

9. The imaging apparatus according to claim 1 , wherein the pulse signal corresponding to the rotation of the imaging core is 512 pulse/rev (15.36 kHz), 1,024 pulse/rev (30.72 kHz), or 2,048 pulse/rev (61.44 kHz).

10. A non-transitory computer readable storage medium that stores the storing a computer program which, when executed by a computer processor causes the imaging apparatus according to claim 1 to generate the ultrasound tomographic image and the optical tomographic image of the target site of the subject using the catheter which rotatably accommodates the imaging core provided with the ultrasound transceiver to transmit and receive the ultrasound wave and the optical transceiver to transmit and receive light.

11. An imaging apparatus configured to generate an ultrasound tomographic image and an optical tomographic image of a target site of a subject using a catheter which rotatably accommodates an imaging core provided with an ultrasound transceiver configured to transmit and receive an ultrasound wave and an optical transceiver configured to transmit and receive light, the imaging apparatus comprising:
a motor drive unit configured to be connected to the catheter and to rotate the imaging core;
a converter configured to receive a pulse signal corresponding to rotation of the imaging core and to convert a repetition frequency of the pulse signal into a converted pulse signal in accordance with a set number of radially-aligned lines configuring one frame of the ultrasound tomographic image;
a transmitting and receiving board configured to generate a drive signal for the ultrasound transceiver and to obtain the ultrasound tomographic image with the set number of radially-aligned lines based on the converted pulse signal to transmit the generated drive signal to the ultrasound transceiver via the motor drive unit; and
a logic device configured to determine a valid pulse in accordance with the set number of radially-aligned lines from the converted pulse signal and to generate a pulse signal representing a timing of sampling of an optical coherence signal for generating the optical tomographic image having a pulse train selected, based on the valid pulse from a pulse signal representing a cycle of a light source generating light for interfering with light from the optical transceiver by setting from pulses in the converted pulse signal, as the valid pulse, a pulse according to a ratio between a number of set lines of the ultrasound image of one frame and a number of set lines of one frame of the optical tomographic image of one frame, and generating a signal having the selected pulse train as the pulse signal representing the timing of the optical coherence signal.

12. The imaging apparatus according to claim 11 , further comprising:
a first A/D (analog to digital) converter and a second A/D (analog to digital) converter, and wherein the transmitting and receiving board is configured to transmit to the first A/D converter a signal of a reflected wave of the ultrasound wave received from the ultrasound receiver via the motor drive unit.

13. The imaging apparatus according to claim 12 , further comprising:
an optical unit con

Assignees

• Terumo Corp
• Terumo Kabishiki Kaisha

Inventors

• Uehara Ryo

Classifications

• H04N25/78

  Readout circuits for addressed sensors, e.g. output amplifiers or A/D converters · CPC title

• A61B5/0035 Primary

  adapted for acquisition of images from more than one imaging mode, e.g. combining MRI and optical tomography · CPC title

• A61B5/0066

  Optical coherence imaging · CPC title

• A61B5/0084

  for introduction into the body, e.g. by catheters (A61B5/1459 takes precedence) · CPC title

• A61B8/12 Primary

  in body cavities or body tracts, e.g. by using catheters · CPC title