The Study On Setting Range Of Micro-CT Operating Voltage, Current And Exposure Time

Computed tomography is one of the most important methods of clinical examination and industrial non-destructive detection. CT had a major impact on industrial production and human life. With the rapid development of modern biological medicine, animal experimentation has gradually become an important method for research on human diseases and drugs, and medical imaging system for small animal studies emerged as the times require.Micro computed tomography also known as the small animal CT, and clinical CT are based on x-ray attenuation characteristics. Compared with the common clinical CT, Micro-CT system with high spatial resolution, won’t destroy the samples and low scan cost, can meet the requirements of animal experiment very well. It has been widely used in many fields, such as cancer research, drug development, materials science and industrial non-destructive testing.This topic originated from small animal multimodality molecular imaging instrumentation research and development projects of Peking University. This project aimed at combining four imaging modules into one integrated imaging system and developing digital image acquisition, processing and management software systems. The four modules include CT(Computed Tomography), Micro-PET(Positron Emission Tomography), SPECT(Single-Photon Emission Computed Tomography) and FMT(Fluorescence Molecular Tomography).In order to study the image fusion technology of integration with Micro-CT and FMT, a set of Micro-CT was built. Experiments with this Micro-CT focus on Micro-CT setting range of voltage, current and exposure time. Composed from many experiments, studying the effects of these parameters on image quality, find the reasonable range of settings.First of all, this paper introduces the development of CT and Micro-CT systems. Explaining the CT system imaging principle and the main hardware and algorithms of Micro-CT. Secondly, a set of dual modality imaging system with Micro-CT/FMT is introduced in this paper, details of its structure and components are described. After its construction, performance has been fully tested. Finally, image evaluation benchmark of Micro-CT is introduced, including spatial and contrast resolution, and the analysis of their influence is systematically introduced. With this Micro-CT, a lot of imaging comparison experiments have been carried out, and different images signal to noise ratio of imaging parameter settings has been discussed, and analyzed the influences of Micro-CT with different parameters.By the study on setting range of Micro-CT operating voltage, current and exposure time, providing data supports for the development of Micro-CT dose imaging system in the future.