CN112450959B - A single-mode PET imaging system and method capable of precise positioning - Google Patents

Abstract

The invention belongs to the technical field of positron emission tomography, and provides a single-mode PET imaging system and method that can realize precise positioning. By setting an incident angle detector around the detector ring, it can be used to accurately measure positron-electron The incident angles of the two gamma photons released after annihilation, and the energy detectors arranged around the detector ring are used to accurately measure the angle between the two gamma photons, so as to determine the annihilation position of the positron in the molecule, and realize In order to achieve the precise positioning of the lesion without relying on the assistance of MR or CT and other means, it not only solves the problem of inaccurate angiography and the detection point is not a real lesion point, but also greatly reduces the cost of the device. The molecular structure of the lesion is determined at the level without the need for pathological sections, avoiding physiological dissection.

Description

A single-mode PET imaging system and method capable of precise positioning

technical field

The invention relates to the technical field of positron emission tomography, in particular to a single-mode PET imaging system and method capable of realizing precise positioning.

Background technique

As a new molecular imaging technology, PET (Positron Emission Computed Tomography) has been widely recognized for its application and contribution in medicine. PET technology uses the positron nuclide carried by the probe molecule as the positron emission source, annihilates with the target molecule or electrons in the target organ, and releases two high-energy gamma photons with an energy of 511keV for imaging. Compared with the traditional imaging technology, the signal photons of PET technology have short wavelength, strong penetrability, and are not easily disturbed by background scattering and Auger effects of other electrons, and will not be hindered by bones in the body. An advanced medical imaging technology for observing and diagnosing pathological lesions at the molecular scale. PET medical imaging technology can be applied to the diagnosis of malignant tumors, nervous system and cardiovascular diseases, which cannot be achieved by other medical imaging technologies.

However, since the current PET only collects gamma photons in the direction of 180 degrees, and because the positron and electron have momentum distribution before annihilation, according to the conservation of momentum, it can be known that the two gamma photons actually deviate from 180 degrees, so in fact this The two gamma photons are not emitted in opposite directions, and there is a certain gap between the measured point and the real annihilation point, resulting in blurred and inaccurate imaging. At the same time, the two gamma photons do not carry any structural information of the lesion molecules, and the reverse extension lines in the outgoing direction cannot intersect to a point, so it is impossible to clearly locate the lesion. Usually, it is necessary to combine MR, CT and other means to assist positioning, forming multiple The modal imaging method is costly and complex in design; the lesion molecules also need to be confirmed by further biological biopsy sections, which require biological dissection.

Contents of the invention

In order to solve the above-mentioned technical problems existing in the prior art, the present invention provides a single-mode PET imaging system and method capable of realizing precise positioning. Mainly by adding a device that can obtain gamma photon energy on the periphery of the detector, and adding a device that measures the incident angle of gamma photons on the inner periphery of the detector, it is possible to achieve lesion detection without relying on the assistance of MR or CT and other technologies. The precise positioning not only solves the problems of inaccurate imaging and detection points that are not real lesion points, but also greatly reduces the cost of the device. At the same time, the PET imaging device of the present invention determines the molecular information of the lesion from the molecular level without making pathological sections, avoiding Physiological anatomy. Specifically, it is mainly realized through the following technical solutions:

A single-mode PET imaging system capable of precise positioning, including a detection module, a data processing module, a lesion molecular database and an analysis module;

The detection module includes a detector ring, an energy detector arranged on the periphery of the detector ring, and an incident angle detector arranged on the inner periphery of the detector ring, the incident angle detector and the energy detector Measure the incident angle and energy distribution information of the two gamma photons released after the positron-electron annihilation;

The data processing module is used to analyze and process the incident angle and energy distribution information measured by the detection module, and obtain the angle between two gamma photons;

The analysis module is used to determine the annihilation position of the positron in the molecule according to the incident angle and the included angle of the two gamma photons, and compare the momentum distribution information with the lesion molecule database to determine the lesion molecular structure;

The data processing module is respectively connected with the detection module, the analysis module and the lesion molecular database.

Preferably, the incident angle detector includes: a substrate, a metal layer and a microlens layer;

The microlens layer refracts gamma photons to form a photosensitive surface that is vertically incident on the sensor layer disposed in the substrate;

The sensor layer performs photoelectric conversion on the sensed gamma photons;

The metal layer transmits the photoelectrically converted electrical signal to the data processing module for processing, and the data processing module obtains the positron- The actual angle of incidence in three-dimensional space of the two gamma photons released after the annihilation of the electron.

Preferably, a display module is also included, and the display module is connected with the data processing module.

Preferably, a human-computer interaction module is also included, and the human-computer interaction module is connected with the data processing module.

A single-mode PET imaging method capable of precise positioning, applied to any one of the above-mentioned single-mode PET imaging systems capable of precise positioning, specifically comprising the following steps:

Use the incident angle detector arranged on the inner periphery of the detection module to measure the incident angle of the two gamma photons released after the positron-electron annihilation, and use the energy detector arranged on the outer periphery of the detection module to measure the positron-electron annihilation The energy distribution information of the two gamma photons released last;

The detection module transmits the measured incident angle and energy distribution information of the two gamma photons to the data processing module;

The data processing module analyzes and processes the incident angle and energy distribution information measured by the detection module, obtains the angle between two gamma photons, and transmits the incident angle, included angle and energy distribution information to the analysis module;

The analysis module determines the annihilation position of the positron in the molecule according to the incident angle and the included angle of the two gamma photons, and compares the momentum distribution information with the lesion molecule database to determine the lesion molecular structure.

The invention has the following beneficial effects: the angle between the two gamma photons released after positron-electron annihilation deviates from 180 degrees, and by setting the incident angle detector on the inner circumference of the detector ring, it can be used to accurately measure the two gamma photons. The incident angle of two gamma photons, and the energy detectors set on the periphery of the detector ring, are used to accurately measure the angle between two gamma photons, so as to determine the annihilation position of the positron in the molecule, and realize the realization of the needless to rely on MR or CT With the aid of other means, the precise positioning of the lesion can be achieved, which not only solves the problems of inaccurate angiography and detection points that are not real lesion points, but also greatly reduces the cost of the device. At the same time, the present invention determines the molecular structure of the lesion from the molecular level, There is no need to make pathological slices, avoiding physiological dissection.

Description of drawings

1. FIG. 1 is a schematic structural diagram of a single-mode PET imaging system capable of achieving precise positioning provided by Embodiment 1 of the present invention;

2. FIG. 2 is a schematic structural diagram of the incident angle detector provided by Embodiment 1 of the present invention;

3. FIG. 3 is a schematic structural diagram of the energy detector provided by Embodiment 1 of the present invention;

4. FIG. 4 is a schematic diagram of a single-mode PET imaging system capable of precise positioning provided by Embodiment 1 of the present invention.

best practice

In order to make those skilled in the art understand more clearly the single-mode PET imaging system and method capable of achieving precise positioning provided by the present invention, it will be described in detail below with reference to the accompanying drawings.

Embodiment one

As shown in Figure 1, the embodiment of the present invention provides a single-mode PET imaging system capable of precise positioning, including a detection module, a data processing module, a lesion molecular database and an analysis module; modules, analysis modules, and lesion molecular database connections.

As shown in Figure 2, the detection module includes a detector ring, an energy detector arranged on the periphery of the detector ring, and an incident angle detector arranged on the inner periphery of the detector ring, and the incident angle detector and the energy detector respectively measure the incident angle and energy distribution information of the two gamma photons released after the positron-electron annihilation.

Preferably, as shown in FIG. 3, the incident angle detector includes: a substrate, a metal layer and a microlens layer;

The microlens layer refracts gamma photons to form a photosensitive surface that is vertically incident on the sensor layer disposed in the substrate;

The sensor layer performs photoelectric conversion on the sensed gamma photons;

The metal layer transmits the photoelectrically converted electrical signal to the data processing module for processing, and the data processing module obtains the positron- The actual angle of incidence in three-dimensional space of the two gamma photons released after the annihilation of the electron.

The data processing module is used to analyze and process the incident angle and energy distribution information measured by the detection module, and obtain the angle between two gamma photons.

Specifically, since the annihilation position is not on the LOR response line, it is necessary to find the angle formed by the two gamma photons, and set an energy detector on the periphery of the detector ring to measure the two gamma photons released after the positron-electron annihilation. The energy of the gamma photon, according to the knowledge of physics, subtracts the angle corresponding to 511kev from the obtained energy value, that is, the angle between two gamma photons. The distance between the annihilation point and the detection modules is still determined by the time when two gamma photons arrive at the respective detection modules, so the distance between the annihilation point and the two detection modules is determined. At this point the included angle and the two distances are uniquely determined. As shown in Figure 4, due to symmetry, there are countless such annihilation points in space, but the angles at which these annihilation points enter the detection module are different. Therefore, it is only necessary to measure the incident angles of two gamma photons to uniquely determine Annihilation position.

Therefore, the analysis module can determine the annihilation position of the positron in the molecule according to the incident angle and the included angle of the two gamma photons, and compare the momentum distribution information with the lesion molecule database to determine the lesion molecular structure.

Preferably, a display module is also included, and the display module is connected with the data processing module.

Preferably, a human-computer interaction module is also included, and the human-computer interaction module is connected with the data processing module.

Embodiment two

The embodiment of the present invention provides a single-mode PET imaging method that can achieve precise positioning, using the incident angle detector arranged in the inner periphery of the detection module to measure the incident angle of the two gamma photons released after the positron-electron annihilation, and using an energy detector arranged on the periphery of the detection module to measure the energy distribution information of the two gamma photons released after the positron-electron annihilation; the detection module will measure the incident angles and The energy distribution information is transmitted to the data processing module; the data processing module analyzes and processes the incident angle and energy distribution information measured by the detection module, obtains the angle between the two gamma photons, and compares the incident angle, the angle and The energy distribution information is transmitted to the analysis module; the analysis module determines the annihilation position of the positron in the molecule according to the incident angle and the included angle of the two gamma photons, and compares the momentum distribution information with the lesion molecular database to determine the lesion molecular structure.

It is applied to any one of the above-mentioned single-mode PET imaging systems that can achieve precise positioning. For specific implementation methods, refer to the above-mentioned embodiments, and details will not be repeated here.

The embodiments of the present invention have been described in detail above, and specific examples have been used in this paper to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only used to help understand the core idea of the present invention; at the same time, for those in the art Ordinary technicians, according to the idea of the present invention, will have changes in the specific implementation and application scope. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims (4)

1. The single-mode PET imaging system capable of realizing accurate positioning is characterized by comprising a detection module, a data processing module, a focus molecule database and an analysis module;

the detection module comprises a detector ring, an energy detector arranged at the periphery of the detector ring and an incident angle detector arranged at the periphery of the detector ring, wherein the incident angle detector and the energy detector respectively measure the incident angle and the energy distribution information of two gamma photons released after positron-electron annihilation; the incidence angle detector includes: a substrate, a metal layer, and a microlens layer; the micro-lens layer refracts gamma photons to form a light sensitive surface which vertically enters a sensor layer arranged in the substrate; the sensor layer performs photoelectric conversion on the sensed gamma photons; the metal layer transmits the photoelectric converted electric signals to the data processing module for processing;

the data processing module is used for analyzing and processing the incidence angle and the energy distribution information measured by the detection module and obtaining the included angle between two gamma photons; the data processing module obtains the actual incidence angles of two gamma photons released after positron-electron annihilation in the three-dimensional space according to the sensitive incidence angle of the micro-lens layer in the three-dimensional space and the corresponding pixel mapping relation;

the analysis module is used for determining the annihilation position of positrons in molecules according to the incidence angles and included angles of two gamma photons, comparing momentum distribution information with the focus molecule database and determining a focus molecule structure;

the data processing module is respectively connected with the detection module, the analysis module and the focus molecule database.

2. The single mode PET imaging system of claim 1, further comprising a display module coupled to the data processing module.

3. The single mode PET imaging system of claim 1, further comprising a human-machine interaction module coupled to the data processing module.

4. A single mode PET imaging method capable of achieving accurate positioning, which is applied to the single mode PET imaging system capable of achieving accurate positioning according to any one of claims 1 to 3, and specifically comprises the following steps:

the method comprises the steps of measuring the incident angles of two gamma photons released after positron-electron annihilation by using an incident angle detector arranged at the inner periphery of a detection module, and measuring the energy distribution information of the two gamma photons released after positron-electron annihilation by using an energy detector arranged at the outer periphery of the detection module; the incidence angle detector includes: a substrate, a metal layer, and a microlens layer; the micro-lens layer refracts gamma photons to form a light sensitive surface which vertically enters a sensor layer arranged in the substrate; the sensor layer performs photoelectric conversion on the sensed gamma photons; the metal layer transmits the photoelectric converted electric signals to the data processing module for processing;

the detection module transmits the incidence angles and the energy distribution information of the two gamma photons obtained by measurement to the data processing module;

the data processing module analyzes and processes the incidence angle and the energy distribution information measured by the detection module, acquires the included angle between two gamma photons, and transmits the incidence angle, the included angle and the energy distribution information to the analysis module; the data processing module obtains the actual incidence angles of two gamma photons released after positron-electron annihilation in the three-dimensional space according to the sensitive incidence angle of the micro-lens layer in the three-dimensional space and the corresponding pixel mapping relation;

the analysis module determines the annihilation position of positrons in molecules according to the incidence angle and the included angle of two gamma photons, and compares momentum distribution information with a focus molecular database to determine a focus molecular structure.