Obtaining method of double-layer crystal position look-up table

Abstract

The invention discloses an acquisition method of a double-layer crystal location lookup table. The method includes the following steps that: a lutecium background single-photon event is acquired in a table mode, the generic-field image I1 of the lutecium background single-photon event is generated according to the lutecium background single-photon event; a coincidence time window is set, a lutecium background coincidence event is obtained, and the generic-field image I2 of the lutecium background coincidence event is generated according to the lutecium background coincidence event; a detector ring inner-layer crystal response vertex P1 is acquired; the generic-field image I2 is deducted from the generic-field image I1, so that the generic-field image I3 of detector ring outer-layer crystal response is acquired, a detector ring outer-layer crystal response vertex P2 is acquired according to the generic-field image I3 of the detector ring outer-layer crystal response; and the crystal location lookup table is automatically generated by using the detector ring inner-layer crystal response vertex P1 and the detector ring outer-layer crystal response vertex P2. According to the method of the invention, the discrimination of two layers of crystals can be realized with introducing an extra radioactive source not required, and the lookup table can be automatically generated.

Description

technical field [0001] The invention relates to the technical field of nuclear medical imaging, in particular to a method for acquiring a double-layer crystal position lookup table. Background technique [0002] Positron emission tomography (PET) is an important imaging modality in nuclear medicine, which can be used for early diagnosis of diseases. The PET detector mainly adopts the design method of discrete scintillation crystal array coupling photodetector array. When the gamma photon is incident on the detector, it interacts with the scintillation crystal to deposit energy; the crystal de-excites to generate a large number of visible photons, which are received by the photodetector with a certain probability after diffusion and are converted into electrical signals; The signal generated by the photodetector is calculated to obtain the action position of the gamma photon. However, due to the actual design of the detector and the problems of the algorithm itself, the pin...

AI Technical Summary

Problems solved by technology

The manual method uses manual interactive operation to draw the segmentation line on the pan-field image, and then uses the algorithm to number the segmented image. The workload is huge, time-consuming and labor-intensive, which is not conducive to the automatic update of the lookup table of the entire PET system, and manual Segmentation is difficult to ensure segmentation accuracy

For the automatic segmentation method, the flood image of the double-layer crystal PET detector is the superposition of the double-layer crystal, therefore, most of the automatic segmentation of the flood-field image of the single-layer crystal detector is not suitable for the automatic segmentation of the double-layer crystal detector, and most The algorithm requires the use of calibrated radioactive sources for pan-field image acquisition, which is not conducive to daily quality control

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