My country’s high-end magnetically compatible brain PET functional imaging equipment achieves zero breakthrough

On February 4, the reporter learned from the Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (referred to as Shenzhen Advanced Institute), that Shenzhen Advanced Institute has successfully developed the first high-definition magnetic resonance compatible human brain PET functional imaging instrument (named “SIAT bPET”). It has achieved zero breakthroughs in the research and development of high-end magnetically compatible brain PET imaging equipment in China.

PET imaging is called positron emission computed tomography (Positron Emission Computed Tomography). ) to label short-lived radionuclides (such as 18F, 11C, etc.), after injection into the human body, the accumulation of the substance in the metabolism is measured by PET imaging, reflecting the life metabolism and functional activities of the organism, so as to achieve the purpose of disease diagnosis .

PET is an imaging that reflects molecular metabolism. When the disease is in the stage of changes at the cellular and molecular levels in the early stage, the morphology and structure of the lesion area has not yet shown abnormality, and the structural imaging examination cannot make a clear diagnosis, PET examination can find the lesion and can Obtain three-dimensional images to achieve qualitative, quantitative, grading, positioning and early diagnosis.

“Usually, due to the depth uncertainty effect of the detector, the spatial resolution of PET imaging instruments will deteriorate as it deviates from the center of the imaging field of view, which seriously affects the imaging accuracy.” Researcher at the Lauterberg Biomedical Imaging Research Center of the Institute of Medical Engineering, Shenzhen Advanced Institute Yang Yongfeng said that their team developed a high-three-dimensional resolution double-ended readout detector, enabling the large-aperture imaging system to achieve a center efficiency of 14% (350-750 keV energy window), and the entire imaging field of view is better than 1.4 mm. Resolution, both performance indicators are at the international leading level.

Caption: SIAT bPET detector system and brain imaging equipment developed by Shenzhen Advanced Institute Photo source: Shenzhen Advanced Institute

Yang Yongfeng introduced that compared with foreign commercial magnetically compatible brain PET imaging instruments, the efficiency of SIAT bPET has increased by nearly 2 times (from 7.2% to 14%), and the average volume resolution has increased by more than 30 times (from about 64 cubic millimeters to 2 cubic millimeters).

Derenzo phantom map obtained by SIAT bPET, human brain FDG metabolic map and rabbit NaF bone scan image. Photo courtesy of Shenzhen Advanced Institute

At the same time, SIAT bPET adopts innovative electronics and magnetic compatibility design, so that the impact of MRI on PET imaging is almost negligible, and the impact of PET imaging on the signal-to-noise ratio of MRI images is less than 5%, which meets the requirements of simultaneous PET/ Cutting-edge research needs of MRI imaging.

It is understood that both PET and MRI are important tools for brain science research and diagnosis of brain diseases. PET’s high sensitivity, high quantitative precision functional metabolic imaging and MRI’s high spatial resolution and high soft tissue contrast anatomical structure imaging are highly complementary. PET and MRI They can also assist each other to further enhance their respective brain neuroimaging capabilities.

PET molecular imaging explores the functions of different brain regions and determines the functional evolution of diseased brain regions by measuring brain blood flow, glucose and oxygen metabolism, protein production, drug distribution, and neurotransmitter dynamics. Intervention treatment strategies and new drug discovery are of great significance.

“However, there is no high-performance brain PET imaging equipment currently on the market, so the American Brain Project is funding the research and development of several high-performance brain PET imaging equipment. Compared with these brain PET imaging equipment under development, the spatial resolution of SIAT bPET The efficiency and efficiency are also at an advanced level.” Yang Yongfeng said.

High spatial resolution makes it possible to study the fine-focus brain functional areas and small nuclei of the brain, and can also improve the quantitative accuracy of brain PET imaging studies by reducing the partial volume effect; high efficiency not only improves the signal-to-noise of brain PET images Recently, the quantitative accuracy of research has been improved, and it has also laid the foundation for high-precision research on neurotransmitter activity and other dynamic brain biochemical and functional activities.” Yang Yongfeng said.

In 2022, team member Kuang Zhonghua orally reported the research results at the International Nuclear Medicine and Molecular Imaging Annual Conference and the IEEE Medical Imaging Conference, which immediately attracted widespread international attention. At the same time, the instrument also provides an important new tool for brain science research based on PET functional imaging, early quantitative diagnosis research of Alzheimer’s disease and other diseases, and new drug development.