Weak Light Detection in Functional Imaging

The book is intended as a detailed guide to use and evaluate the modern digital technology to build modern PET systems. Digital Positron Emission Tomography represents the most modern trend among non-invasive functional nuclear imaging techniques. The term digital is interpreted both in terms of hardware configuration and in terms of data stream analysis. Modern miniaturized sensors realized in Complementary Metal Oxide Semiconductor technology allow to reduce the physical size of detecting pixels to the sub-millimetric range. The new Multi Voltage Threshold method allows to digitize the signals from each pixel within few hundred picoseconds and to collect digital data for further analysis. The modern concept of digital PET requires new techniques of digital data analysis and physical interpretation based on high performance computing platforms, and requires also to define new methods and strategies for the verification of the medical product quality standards. The book will describe the physical fundaments of a novel sensor, the MVT SiPM, able to detect single photons with a space resolution of 50 um and a time resolution of few tens of picosecods. We will describe the physical processes and we will show how to correctly simulate and understand its features. We will show how to a Positron Emission Tomography system based on this sensor, including high performance computing and artificial intelligence approach as techniques for the new generation digital PET systems. The book will make clear the physical and mathematical fundaments of the digital innovation introduced by this new sensor.