Rapid high-resolution mid-IR imaging for molecular spectral histopathological diagnosis of oesophageal cancers

Abstract

This thesis is written as part of Marie-Curie international training network called Mid-TECH. Mid-TECH is devoted to improve mid-infrared (MIR) technologies and consists of 15 PhD projects across European universities. This thesis aims to evaluate new technologies and concepts developed by the project partners for their applicability in a biomedical setting. The clinical problem to diagnose oesophageal cancers serves as an example case for this. The thesis consists of three projects all aimed to further the understanding of MIR hyperspectral imaging. The first project discussed in chapter 5 demonstrates the use of an new design of the United States Airforce resolution test chart. The new test chart is developed to evaluate spatial resolution of MIR hyperspectral imaging systems. The use of different materials is discussed and the new iteration of the thes chart is evaluated using a state of the art MIR imaging system. The second project discussed in chapter 6 evaluates the technical differences and their practical implications of discrete frequency MIR imaging systems compared to continuum source systems. A comparison of the two system types is drawn for imaging paraffin embedded sections of oesophageal tissue. Furthermore the effect of chemically removing the paraffin from the sample is compared to a mathematical correction algorithm. The system performance is compared based on their ability to differentiate healthy from cancerous tissue. The third project discussed in chapter 7 evaluates the potential of a new MIR detection scheme called upconversion in combination with a novel MIR laser source. It is a prove of concept study demonstrating that those two technologies can be deployed to do hyperspectral imaging in the MIR.