Portable imaging device integrating ultrasound and nuclear medicine

Abstract

The present invention provides a portable imaging device integrating ultrasound and nuclear medicine. As a new concept fusion imaging device that simultaneously provides human anatomical information and functional / biochemical information, it can accurately localize lesions during the entire surgical process and can measure in real time. Therefore, compared with PET / CT, SPECT / CT and the like as the original fusion imaging devices, it can ensure the stability of the patient with a small radiation exposure. The device comprises: a transducer, which sends and receives ultrasound; a bonding layer, which, when arranged at the upper end of the transducer, reduces the difference in acoustic resistance between the transducer and the affected part, supports the smooth transmission of the ultrasound beam into the tissue and the high-sensitivity reception of the reflected beam; a sound absorbing member, which absorbs ultrasound on the opposite side of the affected part with the transducer as a reference; and a scintillator, which detects gamma rays as radiation; the sound absorbing member is used as a collimator of a nuclear medicine detector, and the ultrasound medical device and the nuclear medicine detector are integrated into one detector.

Description

Technical Field

[0001] The present invention relates to a portable imaging device that integrates ultrasound and nuclear medicine for precise cancer diagnosis and surgery. More specifically, it relates to a portable imaging device that integrates ultrasound and nuclear medicine. As a new concept of integrated imaging device that can simultaneously provide anatomical information and functional / biochemical information of the human body, it can accurately localize lesions throughout the entire surgical process and can perform real-time measurements. Background Art

[0002] Not only is the population aging rapidly in our country, but the incidence of cancer is also increasing rapidly every year. The society is also paying more attention to the quality of life and health, and the demand for high-level medical services such as precision surgery is increasing.

[0003] Nuclear medicine imaging equipment using radioisotopes such as gamma cameras, PET, and SPECT can visualize the functional and biochemical information of organisms, and are useful for identifying pathological phenomena and disease diagnosis, determining prognosis after treatment, and planning treatment. However, problems with nuclear medicine imaging that provides molecular images are that it provides insufficient anatomical information in terms of biochemical and physical principles, has low resolution, is difficult to accurately localize diseases, and is expensive.

[0004] On the other hand, although the equipment that provides anatomical images, such as MRI, US, and CT, has high image resolution, it has the problem of being difficult to provide functional / biochemical information of a living body.

[0005] Therefore, a fusion imaging device is needed that can add anatomical information that can be obtained in MRI, X-ray CT or ultrasound to the functional information unique to nuclear medicine imaging to make up for the shortcomings of nuclear medicine imaging. Figure 1 , shows examples of MRI images (a), ultrasound images (b), and nuclear medicine images (c) of breast cancer patients. Breast cancer that is unclear in ultrasound images appears clearly in nuclear medicine images.

[0006] PET images have low spatial resolution and relatively little anatomical information. Although CT images have high spatial resolution, they do not provide functional and biochemical information of the organism. PET / CT, which is now the most widely used fusion imaging device, combines PET images and CT images, and has the advantage of being able to accurately understand the location and size of lesions in diagnosis.

[0007] Of the 159 PET and PET / CT devices installed in Korea, only 11 are PET alone, and 148 are PET / CT (as of 2015). Recently, research on new fusion imaging devices such as PET / MRI and PET / optics has increased, and attention to fusion imaging devices is rising. However, the most widely used PET / CT cannot be used in real time or during surgery, and there is a risk of exposing patients to radiation energy.

[0008] Therefore, it is necessary to develop a new concept fusion imaging device that can be used in real time and minimize the amount of radiation exposure to the human body. On the other hand, in the field of nuclear medicine, gamma detectors and gamma cameras can be made into handheld probes, unlike PET, SPECT, etc., and are often used for early diagnosis of diseases such as cancer, cancer detection during surgery, or sentinel lymph node biopsy (to determine whether there is metastatic cancer).

[0009] Ultrasonic medical equipment is often used to diagnose human organs because ultrasound is harmless to the human body, does not require any pre-treatment including injection of contrast agents, has high accuracy, and is often used to diagnose human organs. Summary of the invention

[0010] Technical Challenges

[0011] In order to solve the above problems, the purpose of the present invention is to provide an imaging device as a new concept fusion imaging device that simultaneously provides human anatomical information and functional / biochemical information. It can accurately localize lesions throughout the entire operation and can measure them in real time. Compared with PET / CT, SPECT / CT and other original fusion imaging devices, it can ensure the stability of the patient with a small radiation exposure.

[0012] In addition, the present invention aims to improve the accuracy and stability of killing cancerous tissue in a non-invasive manner by integrating with high-intensity focused ultrasound (HIFU) surgical device.

[0013] Means of solving tasks

[0014] The portable imaging device of the present invention, which is intended to achieve the above-mentioned purpose, that integrates ultrasound and nuclear medicine, includes: a transducer that sends and receives ultrasound; a bonding layer that, when disposed on the upper end of the transducer, reduces the difference in acoustic resistance between the transducer and the affected area, thereby supporting the smooth transmission of the ultrasound beam into the tissue and the high-sensitivity reception of the reflected beam; a sound-absorbing component that absorbs ultrasound on the opposite side of the affected area based on the transducer; and a scintillator that detects gamma rays as radiation; the sound-absorbing component is used as a collimator of a nuclear medicine detector to integrate the ultrasound medical equipment and the nuclear medicine detector into one detector.

[0015] The transducer and scintillator adopt a crystal capable of sending and receiving ultrasonic waves and converting radiation energy into light. The crystal is selected from materials including lanthanum tantalum gallium aluminate, lanthanum niobium gallium aluminate, and strontium niobium gallium silicate.

[0016] Effects of the Invention

[0017] The present invention utilizes precision cancer diagnosis, surgical ultrasound and nuclear medicine fusion imaging equipment to simultaneously obtain anatomical information and functional / biochemical information of the lesion in real time throughout the entire surgical process, enabling a more accurate diagnosis.

[0018] In addition, by presenting a relatively smaller radiation exposure than existing fusion imaging devices such as PET / CT and SPECT / CT, patient safety can be ensured.

[0019] In addition, by integrating with high-intensity focused ultrasound (HIFU), the accuracy and stability of non-invasive lesion treatment and tumor removal technology can be improved. As mentioned above, since it is a new concept fusion imaging device that has never existed before, it can even be expanded to the development of new diagnostic and treatment theories, and it can open up a new medical device market.

[0020] The present invention can obtain all ultrasonic signals and gamma-ray signals by only one portable detector, and can process all ultrasonic signals and gamma-ray signals by only one circuit, so that fused images can be obtained in real time and production costs can be reduced.

[0021] In addition to the medical field, it is expected to be applied to non-destructive inspection fields such as measuring the thickness and density of concrete and pipes. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Examples showing MRI images (a), ultrasound images (b), and nuclear medicine images (c) of a breast cancer patient.

[0023] Figure 2 A structural diagram of a probe for ultrasound-nuclear medicine fusion diagnosis using a scintillator and a light sensor is shown according to one embodiment of the present invention.

[0024] Figure 3 A structural diagram of a probe for ultrasound-nuclear medicine fusion diagnosis using a room temperature semiconductor detector is shown according to another embodiment of the present invention.

[0025] Figure 4 According to another embodiment of the present invention, a structural diagram of a probe for ultrasound-nuclear medicine fusion diagnosis using a material that can simultaneously realize a transducer and radiation detection (eg, lanthanum gallium tantalum aluminate, lanthanum gallium niobium aluminate, etc.) is shown.

[0026] Figure 5 An integrated electronic circuit for an ultrasound-nuclear medicine fusion diagnosis detector is shown, which has a method of selectively receiving an ultrasound signal or a gamma signal using a switching circuit.

[0027] Figure 6 An integrated electronic circuit for an ultrasound-nuclear medicine fusion diagnostic probe is shown, which has a method of extracting and distinguishing ultrasound signals from gamma-ray signals from ultrasound / gamma composite signals using filters.

[0028] Figure 7 A structural diagram of a probe for ultrasound-nuclear medicine fusion diagnosis using a scintillator and a photo sensor is shown according to yet another embodiment of the present invention.

[0029] Figure 8 A structural diagram of a probe for ultrasound-nuclear medicine fusion diagnosis using a room temperature semiconductor detector is shown according to yet another embodiment of the present invention. DETAILED DESCRIPTION

[0030] The present invention will be described in more detail below by way of examples. These examples are only used to illustrate the present invention and should not be interpreted as limiting the scope of the present invention by these examples, which is self-evident to those skilled in the art.

[0031] Hereinafter, according to the present invention, the components of a portable ultrasound-nuclear medicine fusion imaging device for precise cancer diagnosis and surgery will be described.

[0032] As an embodiment of an ultrasound-nuclear medicine fusion probe, there is a nuclear medicine collimator design using ultrasound sound absorbing materials.

[0033] The transducer of ultrasonic medical equipment is a component for transmitting and receiving ultrasonic waves, and mainly uses crystals such as lead zirconate titanate, lead magnesium niobate, lanthanum gallium tantalum aluminate, and lanthanum gallium niobate aluminate. This transducer is a component that generates ultrasonic waves when receiving electric current, and generates electric current when receiving ultrasonic waves. The direction of the ultrasonic waves generated at this time is the radiation direction, so the image quality of the affected area will be reduced because the ultrasonic waves are generated on the opposite side of the affected area as the area of ​​interest.

[0034] To prevent this problem, the sound-absorbing material (epoxy resin + tungsten powder) that absorbs ultrasound waves is placed on the opposite side of the affected area based on the transducer to attenuate the reverse ultrasound waves that can reduce the image quality. Generally speaking, the sound-absorbing material is made of a high-density material to attenuate ultrasound waves.

[0035] On the other hand, gamma rays have high transmissivity, so in order to accurately detect the desired location, a collimator that can limit the direction of gamma rays is required. In order to attenuate gamma rays from unnecessary directions, the collimator is also made of high-density material.

[0036] Therefore, if Figure 2 As shown in the figure, the ultrasonic medical device and the nuclear medicine detector are combined into one detector by using the sound absorbing material of the ultrasonic medical device as a collimator. Figure 2 In the process, the bonding layer plays the role of reducing the difference in acoustic impedance between the probe and the skin, helping the ultrasonic beam to be efficiently transmitted into the tissue, and the reflected beam can be received with high sensitivity.

[0037] The electrode plays the role of transmitting the current required for transmitting ultrasound to the transducer or transmitting the current generated when receiving ultrasound to the circuit. The scintillator is an element that generates light proportional to the energy of the gamma ray when receiving gamma rays. At this time, the generated light is transmitted to the optical sensor (silicon photomultiplier (SiPM), avalanche photodiode (APD), etc.), converted into an electrical signal and transmitted to the circuit.

[0038] On the other hand, Figure 7 As shown, low-density air or sound-absorbing material may be additionally arranged between the scintillator and the electrode.

[0039] As another embodiment of the ultrasound-nuclear medicine fusion detector, it has a high-density room-temperature semiconductor radiation detector method.

[0040] Instead of scintillators and photosensors (SiPM, APD, etc.), room temperature semiconductor radiation detectors (e.g., CZT, CdTe, etc.) are used. Semiconductor radiation detectors are expected to function as both radiation detectors and sound absorbing materials due to their high density. Figure 3 As shown, a semiconductor detector can be used to replace part or all of the sound absorbing material to form an ultrasound-nuclear medicine fusion detector.

[0041] On the other hand, Figure 8 As shown, low-density air or sound-absorbing material may be additionally arranged between the lower end of the crystal and the semiconductor detector.

[0042] The present invention uses a material that can realize both transducer and radiation detection.

[0043] Crystal materials such as lanthanum gallium tantalum aluminate, lanthanum gallium niobium aluminate, and strontium gallium niobium silicate are transducers that generate electrical signals when receiving ultrasound and generate ultrasound when receiving electrical signals, but they can also function as scintillators that convert radiation energy into light when gamma rays or other radiation are incident. Therefore, using these materials, both ultrasonic signals and radiation signals can be detected with one detector.

[0044] In addition, in order to detect the light generated when radiation is incident, a light sensor must be attached to the bottom of the crystal, and in order to send and receive ultrasonic waves, electrodes must be attached to the top and bottom of the crystal.

[0045] Therefore, if Figure 4 As shown, if a transparent electrode is attached to the lower end of the crystal, the above requirements can be met simultaneously.

[0046] An example of the ultrasound-nuclear medicine portable fusion imaging device of the present invention has an electronic circuit method for an ultrasound / gamma fusion detector.

[0047] An integrated electronic circuit for an ultrasound-nuclear medicine fusion diagnostic detector is shown, and an ultrasound / gamma switching circuit utilizes a switching circuit to selectively receive an ultrasound signal or a gamma signal.

[0048] The core of the ultrasonic / gamma switching circuit is a method of using idle time to receive gamma-ray signals during the transmission and reception of ultrasonic signals.

[0049] like Figure 5 As shown, it is composed of an ultrasonic transmitting and receiving unit, a signal identification and processing unit, and a nuclear medicine detector unit. It uses a digitally controlled analog switch to alternately process ultrasonic signals and gamma ray signals.

[0050] Another example of the ultrasonic-nuclear medicine portable fusion imaging device of the present invention has an ultrasonic / gamma circuit method using a filter.

[0051] An integrated electronic circuit for an ultrasound-nuclear medicine fusion diagnostic detector is shown. The ultrasound / gamma circuit using a filter uses a filter to extract and distinguish ultrasound signals and gamma ray signals from ultrasound / gamma composite signals.

[0052] The ultrasonic / gamma circuit using a filter is a circuit that receives ultrasonic signals and gamma ray signals at the same time, and uses a filter to extract and distinguish ultrasonic signals and gamma ray signals from the ultrasonic / gamma ray composite signal. Figure 6 As shown, it is composed of an ultrasonic transmitting and receiving unit, a signal identification and processing unit, and a nuclear medicine detector unit. After the synthetic signal is converted into a digital signal by an ADC, the ultrasonic signal and the gamma ray signal are extracted and distinguished by a digital filter.

[0053] The present invention is described above by way of embodiments, but the present invention is not limited thereto. The embodiments may be revised or modified without departing from the spirit and scope of the present invention, and those skilled in the art will appreciate that such revisions and modifications also belong to the present invention.

Claims

1. A portable imaging device integrating ultrasound and nuclear medicine, as a portable imaging device integrating ultrasound and nuclear medicine, characterized in that: include: a transducer that transmits an ultrasonic beam and receives a reflected beam; A bonding layer, wherein the bonding layer, when disposed on the first surface of the transducer, reduces the difference in acoustic impedance between the transducer and the affected part, and supports smooth transmission of the ultrasonic beam into the tissue and reception of the reflected beam; an absorber including a first sound absorbing material disposed on a second surface opposite to the first surface of the transducer; a transmission layer, disposed on the second surface and transmitting gamma rays, the transmission layer comprising air or a second sound absorbing material having a lower density than the first sound absorbing material; and a scintillator, disposed on the transmission layer, for detecting the gamma rays generated in the affected part and transmitted through the transducer and the bonding layer; The absorber is regarded as a sound absorber and collimator of the portable imaging device integrating ultrasound and nuclear medicine. wherein the side surface of the scintillator and the transmission layer are surrounded by the sound absorber and the collimator, wherein the absorber absorbs the ultrasonic beam transmitted in the direction from the first surface to the second surface and attenuates the gamma rays from unnecessary directions, and Wherein, the transducer and the scintillator are selected from any one of the three crystals of LTGA, LGNA and SNGS.

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